The Development of Agricultural Antibiotics - ACS Publications

10 The Development of Agricultural Antibiotics TOMOMASA MISATO

Downloaded by UNIV OF ARIZONA on May 26, 2017 | http://pubs.acs.org Publication Date: June 1, 1977 | doi: 10.1021/bk-1977-0037.ch010

The Institute of Physical and Chemical Research, Wako-shi, Saitama 351, Japan

Introduction The successful use of a n t i b i o t i c s against b a c t e r i a l diseases of human beings has led to a large scale screening of a n t i b i o t i c s effect for plant disease control in the world. Many a n t i b i o t i c s developed for medical purposes were investigated for a c t i v i t y against plant pathogens. Furthermore screening of soil organisms for production of a n t i b i o t i c substances was started with the prime purpose of plant disease c o n t r o l . However, the results obtained with a n t i b i o t i c s and a n t i b i o t i c containing culture broth did not fulfil the high expectations. Many of them were too unstable under field conditions or showed toxic side effects on plants. Most a n t i b i o t i c s were rather expensive, even when used as a crude product. In western countries only a few a n t i b i o t i c s have been developed for p r a c t i c a l use. These are streptomycin, tetra cycline, cycloheximide and g r i s e o f u l v i n . Streptomycin, the first a n t i b i o t i c introduced in a g r i c u l t u r e , was used in the United States for the control of pear f i r e b l i g h t . This a n t i b i o t i c and a mixture of streptomycin and tetracycline have been used for the control of b a c t e r i a l plant diseases, while cycloheximide and griseofulvin have been used for the control of fungal plant diseases. Cycloheximide is a very powerful fungicide, but unfor tunately, highly toxic to plants, which r e s t r i c t s its use against plant diseases. Griseofulvin i s a much less phytotoxic systemic fungicide, but its use is also restricted, because the r e l a t i o n of its manufacturing cost to its performance under field condition is not quite satisfactory. In Japan, these four a n t i b i o t i c s had been used only on a very l i m i t e d scale for p r a c t i c a l control of plant diseases, u n t i l the curative effect of blasticidin S on r i c e blast was discovered by the author's research group i n 1958. The successful application of blasticidin S against r i c e blast has stimulated the development of a g r i c u l t u r a l a n t i b i o t i c s and led to the discovery of several excellent a n t i b i o t i c s , such as kasuga mycin, polyoxins and validamycin etc. Nowadays, blasticidin S and kasugamycin have been in p r a c t i c a l use for r i c e blast control instead of mercuric fungicides, and polyoxins and validamycin have ;

170

Plimmer et al.; Pesticide Chemistry in the 20th Century ACS Symposium Series; American Chemical Society: Washington, DC, 1977.


1974

1968

1964

1964

1957

1972

1970

1967

1965

1961

1959

1959

Registration

Insecticidal Antibiotics Tetranactin

ANTIBACTERIAL ANTIBIOTICS Streptomycin (Wettable Powder) Cellocidin (Wettable Powder) Chloramphenicol +Basic copper (Wettable Powder) Novobiocin (Solution)

ANTIFUNGAL ANTIBIOTICS Cycloheximide (Wettable Powder) Griseofulvin (Paste) Blasticidin S (Dust) (Wettable Powder) (Solution) Kasugamycin (Dust) (Wettable Powder) (Solution) Polyoxins (Dust) (Wettable Powder) (Solution) Ezomycin (Wettable Powder) Validamycin (Dust) (Wettable Powder)

Antibiotics

Blight

Insects Carmine Mite of F r u i t s and Tea

B a c t e r i a l Canker of Tomatoes

B a c t e r i a l Diseases of F r u i t s and Vegetables Rice B a c t e r i a l Leaf B l i g h t Rice B a c t e r i a l Leaf B l i g h t

Rice Sheath

Stem Rot of Kidney Bean

Rice Sheath B l i g h t Fungal Diseases of F r u i t s and Vegetables

Rice Blast

Rice B l a s t

Onion Downy Mildew Shoot B l i g h t of Japanese Larch Fusarium W i l t of Melon

Diseases

0

10

0

349

3,893 94

0

387 418 34

7,930 265 10

1,250 3 152

2

17

(ton)

(10

0

33,130

0

692,086

513,876 143,256

0

32,121 960,982 38,216

507,762 221,805 8,820

75,000 2,547 102,426

4,700

3

(1974)

35,020

Amounts used i n Japan

Table I . A g r i c u l t u r a l A n t i b i o t i c s used i n Japan


yen)

PESTICIDE C H E M I S T R Y


172

IN T H E 2 0 T H

CENTURY

been used t o c o n t r o l t h e s h e a t h b l i g h t o f r i c e p l a n t i n s t e a d o f arsenic fungicides. The amount o f a n t i b i o t i c s u s e d i n J a p a n i s shown i n T a b l e I . The d e v e l o p m e n t o f a g r i c u l t u r a l a n t i b i o t i c s has n o t b e e n l i m i t e d o n l y f o r c o n t r o l l i n g p l a n t d i s e a s e s , b u t h a s e x t e n d e d w i d e r and more a c t i v e l y o v e r v a r i o u s a r e a s s u c h a s u t i l i z a t i o n o f i n s e c t i c i d e s , h e r b i c i d e s and p l a n t r e g u l a t o r s i n J a p a n . As shown i n T a b l e I I , many compounds o f m i c r o b i o l o g i c a l o r i g i n a r e a l r e a d y u s e d as p e s t i c i d e s o r show p r o m i s e f o r practical application. B l a s t i c i d i n S; e t c . as a n t i f u n g a l a n t i b i o t i c s , s t r e p t o m y c i n , e t c . as a n t i b a c t e r i a l a n t i b i o t i c s , t e t r a n a c t i n as a m i t i c i d e , and g i b b e r e l l i n s as p l a n t g r o w t h r e g u l a t o r s a r e p r a c t i c a l l y u s e d . A a b o m y c i n as an a n t i v i r a l a n t i b i o t i c , a p r o d u c t o f B a c i l l u s t h u r i n g e n s i s as a i n s e c t i c i d a l a n t i b i o t i c and a n i s o m y c i n d e r i v a t i v e s as h e r b i c i d e s h a v e b e e n t e s t e d f o r p r a c t i c a l use i n the f i e l d s . Table I I .

Pesticidal

compounds o f m i c r o b i o l o g i c a l

[Fungicide] * Antifungal antibiotics * Antibacterial antibiotics Antiviral antibiotics [insecticide] * Miticidal antibiotic * Bacterial toxin [Herbicide] Herbicidal antibiotic [Growth r e g u l a t o r ] * Fungal product

: : :

B l a s t i c i d i n S, e t c . Streptomycin, e t c . Aabomycin, e t c .

:

Tetranactin

:

Bacillus

:

Anisomycin

: *

origin

thuringensis

Gibberellins

P r a c t i c a l l y u s e d as p e s t i c i d e s

R e v i e w s on many a n t i b i o t i c s i n c l u d i n g c y c l o h e x i m i d e , g r i s e o f u l v i n and s t r e p t o m y c i n t e s t e d f o r t h e p u r p o s e o f a g r i c u l t u r a l use i n w e s t e r n c o u n t r i e s have been p u b l i s h e d ( 1 - 6 ) . I ti s the purpose o f t h i s paper t o d i s c u s s t h e p r e s e n t s t a t u s o f a n t i b i o t i c s a s p l a n t d i s e a s e c o n t r o l a g e n t s . The d i s c u s s i o n w i l l m a i n l y be l i m i t e d t o a n t i b i o t i c s w h i c h a r e p r a c t i c a l l y u s e d a s new p e s t i c i d e s i n J a p a n . F o r t h e o t h e r l i t e r a t u r e , t h e r e a d e r may r e f e r t h e r e v i e w s m e n t i o n e d above. Antifungal

antibiotics

B l a s t i c i d i n S. B l a s t i c i d i n S i s t h e f i r s t s u c c e s s f u l a g r i c u l t u r a l a n t i b i o t i c developed i n Japan. I t was i s o l a t e d f r o m t h e c u l t u r e f i l t r a t e s o f Streptomyces griseochromogenes by T a k e u c h i e t a l . ( 7 ) , and t h e p o t e n t c u r a t i v e e f f e c t o f b l a s t i c i d i n S on r i c e b l a s t was f o u n d b y M i s a t o elt a l . ( 8 ) . T h e r e a f t e r t h e b e n z y l aminobenzene s u l f o n a t e o f b l a s t i c i d i n S was r e p o r t e d t o be l e a s t phytotoxic to the host plant without reducing antifungal a c t i v i t y a g a i n s t P y r i c u l a r i a o r y z a e , t h e p a t h o g e n o f r i c e b l a s t ( 9 ) , and


MisATO

10.

Agricultural

173

Antibiotics

t h i s s a l t has been i n d u s t r i a l l y produced f o r a g r i c u l t u r a l use. 1) C h e m i s t r y a n d mode o f a c t i o n : The c h e m i c a l s t r u c t u r e o f b l a s t i c i d i n S has been s t u d i e d e x t e n s i v e l y by Yonehara and h i s c o - w o r k e r s a n d t h e f i n a l s t r u c t u r e a s s i g n e d b l a s t i c i d i n S i s 1(l -cytosinyl)-4-[L-3 -amino-5 -(l -N-methylguandidino)-valerylamino]-!,2,3,4-tetradeoxy-B-D-erythro-hex-2-eneuronic a c i d as shown i n F i g u r e 1 ( 1 0 , 1 1 ) . S e t o e t a l . (12,13) s t u d i e d t h e b i o s y n t h e s i s o f b l a s t i c i d i n S by the p r o d u c i n g organism u s i n g Relabeled suspected precursors. The r e s u l t s o b t a i n e d w e r e t h a t t h e p y r i m i d i n e r i n g o f t h e a n t i b i o t i c came f r o m c y t o s i n e d i r e c t l y a n d sugar moiety from g l u c o s e ; a r g i n i n e s e r v e d as t h e p r e c u r s o r f o r b l a s t i d i c a c i d , and t h e N - m e t h y l group o f b l a s t i d i c a c i d a r o s e from m e t h i o n i n e . M i s a t o and h i s co-workers have s t u d i e d t h e b i o c h e m i c a l p r o p e r t i e s o f b l a s t i c i d i n S on _P. o r y z a e . They f o u n d t h e c u r a t i v e e f f e c t o f b l a s t i c i d i n S on r i c e b l a s t due t o a s t r o n g i n h i b i t o r y a c t i o n on m y c e l i a l g r o w t h o f t h e p a t h o g e n , and r e p o r t e d t h a t t h e a n t i b i o t i c m a r k e d l y i n h i b i t e d t h e i n c o r p o r a t i o n o f Rel a b e l e d amino a c i d i n t o p r o t e i n i n t h e c e l l - w a l l s y s t e m o f ]?. o r y z a e ( 1 4 ) , w h i l e m e t a b o l i c pathways i n c l u d i n g g l y c o l y s i s , s u c c i n i c d e h y d r o g e n a s e s y s t e m , e l e c t r o n t r a n s p o r t s y s t e m , and o x i d a t i v e p h o s p h o r y l a t i o n s y s t e m o r i n c o r p o r a t i o n o f ^2p i n t o t h e n u c l e i c a c i d w e r e n o t i n h i b i t e d b y b l a s t i c i d i n S ( 1 5 , 1 6 ) . The mode o f a c t i o n o f t h i s a n t i b i o t i c on t h e m o l e c u l a r b a s i s i n d e t a i l i s n o t known s o f a r w i t h any c e r t a i n t y , b u t c e r t a i n p r o c e s s e s r e l a t e d t o p e p t i d y l transferase a c t i v i t y a r ei n h i b i t e d by b l a s t i c i d i n S (17,18).


1

1

1

! !

2) Biological properties: B l a s t i c i d i n S has a wide range of b i o l o g i c a l a c t i v i t i e s . Besides i t s s i g n i f i c a n t i n h i b i t o r y e f f e c t s on t h e g r o w t h o f ]?. o r y z a e , i t a l s o e x h i b i t s o t h e r a n t i m i c r o b i a l ( 7 ) , and a n t i - v i r a l (19) a s w e l l a s a n t i - t u m o r a c t i v i t i e s ( 2 0 ) , t h o u g h t h e m e d i c i n a l a p p l i c a t i o n s a r e impeded b y i t s toxic properties. I n t h e case o f spraying i n t h e f i e l d t o pro tect r i c e b l a s t , thee f f e c t i v e concentration of b l a s t i c i d i n S i s u s u a l l y 10 t o 20 ppm ( 1 - 3 g b l a s t i c i d i n S / 1 0 a ) , b u t i t o c c a s i o n a l l y c a u s e s c h e m i c a l i n j u r y on r i c e l e a v e s when s p r a y e d b e y o n d t h e c o n c e n t r a t i o n d e s c r i b e d above. The a p p l i c a t i o n b y d u s t i n g o c c a s i o n a l l y causes c o n j u n c t i v i t i s i f i t a c c i d e n t a l l y c o n t a c t s t h e eyes, a l t h o u g h no a c c i d e n t has been r e p o r t e d i n t h e c a s e o f t h e s p r a y o f w e t t a b l e powder o r s o l u t i o n . Such t o x i c e f f e c t on mammals i s t h e most u n f a v o r a b l e c h a r a c t e r i s t i c o f b l a s t i c i d i n S. Many a t t e m p t s h a v e b e e n made t o remedy t h i s d e f e c t o f b l a s t i c i d i n S. S u g i m o t o (21) f o u n d a s i m p l e method t o a l l e v i a t e e y e i r r i t a t i o n c a u s e d b y b l a s t i c i d i n S; t h e a d d i t i o n o f calcium acetate t o b l a s t i c i d i n S dust (5% a d d i t i o n ) s p e c i f i c a l l y r e d u c e d t h e e y e t r o u b l e w i t h o u t i n f l u e n c e on a n t i b l a s t e f f e c t , t h o u g h o t h e r mammalian t o x i c i t y o r p h y t o t o x i c i t y o f t h e a n t i b i o t i c are also not affected. T h i s i m p r o v e d d u s t i s now u s e d p r a c t i c a l l y f o r a g r i c u l t u r a l use. The b e h a v i o r a n d f a t e o f b l a s t i c i d i n S i n t h e environment were i n v e s t i g a t e d u s i n g r a d i o -



PESTICIDE C H E M I S T R Y IN T H E 2 0 T H C E N T U R Y

Figure 2.

Structure of kasugamycin



10.

MisATO

Agricultural

Antibiotics

175

a c t i v e compounds p r e p a r e d b i o s y n t h e t i c a l l y f r o m C - c y t o s i n e and C - L - m e t h i o n i n e ( 2 2 ) . The s p r a y e d a n t i b i o t i c was l o c a t e d on t h e s u r f a c e o f t h e r i c e p l a n t a n d l i t t l e was d i f f u s e d o r t r a n s p o r t e d i n t o t h e t i s s u e . From t h e wound o r i n f e c t e d p a r t , however, t h e compound was i n c o r p o r a t e d and t r a n s l o c a t e d m a i n l y t o u p p e r p a r t . The compound l o c a t e d a t t h e p l a n t s u r f a c e was decomposed b y s u n l i g h t a n d gave r i s e t o c y t o s i n e a s t h e m a i n d e g r a d a t i o n product. A considerable quantity o f b l a s t i c i d i n S sprayed f e l l t o t h e g r o u n d a n d was a d s o r b e d on t h e s o i l s u r f a c e t i g h t l y . Further more, s i g n i f i c a n t g e n e r a t i o n o f - ^ C - c a r b o n d i o x i d e f r o m t h e - ^ C i b l a s t i c i d i n S t r e a t e d s o i l was o b s e r v e d , and s e v e r a l m i c r o b e s u s u a l l y i n h a b i t i n g t h e paddy f i e l d w e r e f o u n d t o make t h e b i o l o g i c a l a c t i v i t y o f b l a s t i c i d i n S lower. From t h e r e s u l t s o b t a i n e d , Y a m a g u c h i et_ a l . s u p p o s e d t h a t a f t e r a p p l i c a t i o n t o t h e c r o p a t very low c o n c e n t r a t i o n , t h e a n t i b i o t i c might be r a p i d l y broken down i n t h e e n v i r o n m e n t , s o t h a t t h e r e may b e no d a n g e r o f e n v i r o n m e n t a l p o l l u t i o n and food contamination. Kasugamycin. K a s u g a m y c i n i s a w a t e r - s o l u b l e and b a s i c a n t i b i o t i c produced by Streptomyces kasugaensis (23). F o l l o w i n g t h e d e v e l o p m e n t o f b l a s t i c i d i n S, k a s u g a m y c i n h a s b e e n u s e d a s a n a g r i c u l t u r a l a n t i b i o t i c f o r r i c e b l a s t c o n t r o l i n Japan s i n c e 1965. This a n t i b i o t i c controls r i c e b l a s t disease a t a concentra t i o n a s l o w a s a b o u t 20 ppm. I t c a n b e s a f e l y u s e d w i t h o u t a n y t o x i c i t y on c r o p s , and w i t h v e r y l o w t o x i c i t y t o mammals. These advantages a r e t h e main r e a s o n s t h a t b l a s t i c i d i n S i s l o s i n g ground t o kasugamycin. However, r e c e n t l y , t h e v i r u l e n c e o f kasugamycin-resistant s t r a i n i n paddy f i e l d h a s r a i s e d a s e r i o u s problem i n r i c e b l a s t c o n t r o l by kasugamycin. 1) C h e m i s t r y and mode o f a c t i o n : The c h e m i c a l s t r u c t u r e o f k a s u g a m y c i n was s t u d i e d b y S u h a r a elt a l . (24,25) b y c h e m i c a l methods a n d b y I k e k a w a e t a l . (26) b y X - r a y d i f f r a c t i o n a n a l y s i s . As shown i n F i g u r e 2, t h e m o l e c u l e o f k a s u g a m y c i n c o n s i s t s o f t h r e e m o i e t i e s w h i c h a r e D - i n o s i t o l , kasugamine (2,3,4,6-tetrad e o x y - 2 , 4 - d i a m i n o h e x o p y r a n o s e ) and an i m i n o a c e t i c a c i d s i d e c h a i n . N a k a j i m a and h i s a s s o c i a t e s s t u d i e d t h e s y n t h e s i s o f k a s u g a m y c i n , and s u c c e e d e d i n s y n t h e s i z i n g k a s u g a n o b i o s a m i n e and r e l a t e d com pounds ( 2 7 , 2 8 ) ; t h a t means t h e t o t a l s y n t h e s i s o f k a s u g a m y c i n b y t h e i n t r o d u c t i o n o f t h e o x a l i m i d y l group i n t o k a s u g a n o b i o s a m i n e . K a s u g a m y c i n e n t e r s i n t o t h e p l a n t t i s s u e , a n d shows b o t h p r o t e c t i v e and c u r a t i v e a c t i o n . I t does n o t i n h i b i t s p o r e g e r m i n a t i o n even a t a c o n c e n t r a t i o n o f 120 ug/ml. I t s effect against £.· o^yzae comes o n l y t o e x p r e s s i o n i n t h e p l a n t a n d i n v i t r o a t l o w pH ( 2 9 ) . T a n a k a jet a l . (30) r e p o r t e d t h a t k a s u g a m y c i n i n h i b i t e d p r o t e i n s y n t h e s i s i n c e l l f r e e s y s t e m s o f ]?. o r y z a e . Kasugamycin i n h i b i t s p r o t e i n s y n t h e s i s i n E s c h e r i c h i a c o l i b y i n t e r f e r i n g w i t h t h e b i n d i n g o f a m i n o a c y l - t R N A t o mRNA-30 S r i b o s o m a l s u b u n i t complex. The compound does n o t c a u s e m i s c o d i n g .


PESTICIDE C H E M I S T R Y IN

176

THE

20TH

CENTURY

2) B i o l o g i c a l p r o p e r t i e s : K a s u g a m y c i n s e l e c t i v e l y i n h i b i t e d t h e g r o w t h o f P. ovyzae and some b a c t e r i a i n c l u d i n g Pseudomonas s p e c i e s , and showed l i t t l e o r no a c t i v i t y a g a i n s t o t h e r f u n g i tested. The a n t i b i o t i c d i d n o t show a c u t e o r c h r o n i c t o x i c i t y t o m i c e , r a t s , r a b b i t s , d o g s , monkeys and human b e i n g s . The o r a l LD f o r m i c e was 2 g/kg. A t a c o n c e n t r a t i o n o f 1,000 ppm t h e r e was no t o x i c i t y t o f i s h . K a s u g a m y c i n i s now u s e d i n a l a r g e scale against r i c e blast. I t c o n t r o l s r i c e b l a s t when s p r a y e d a t a b o u t 20 - 40 ppm aqueous s o l u t i o n . For p r a c t i c a l disease c o n t r o l k a s u g a m y c i n i s m a i n l y a p p l i e d a s a d u s t , c o n t a i n i n g 0.3 % o f a c t i v e i n g r e d i e n t . No i n j u r y was o b s e r v e d t o many o t h e r p l a n t s . The d e v e l o p m e n t o f r e s i s t a n c e i n f u n g i t o k a s u g a m y c i n has been r e p o r t e d from l a b o r a t o r y experiments, but not i n the f i e l d s f o r some y e a r s a f t e r a p p l i c a t i o n o f t h e a n t i b i o t i c . However, s i n c e 1971, t h e d e v e l o p m e n t o f a k a s u g a m y c i n - r e s i s t a n t s t r a i n o f r i c e b l a s t f u n g u s i n t h e f i e l d s has become a s e r i o u s p r o b l e m ( 3 1 ) . A f t e r k a s u g a m y c i n r e s i s t a n t s t r a i n s had b e e n d e t e c t e d i n t h e f i e l d , t h e c o m b i n e d f o r m u l a t i o n s o f k a s u g a m y c i n and c h e m i c a l s w i t h d i f f e r e n t a c t i o n mechanisms h a v e b e e n p r a c t i c a l l y u s e d .


5 0

Polyoxins. The p o l y o x i n s , a new g r o u p o f p e p t i d y l - p y r i m i d i n e n u c l e o s i d e a n t i b i o t i c s , a r e p r o d u c e d by Streptomyoes oaoaoi v a r . asoensis (32,33). P o l y o x i n s a r e composed o f t h i r t e e n components (A - M) o f some c l o s e l y r e l a t e d " p e p t i d i c n u c l e o s i d e s " as r e f e r r e d by I s o n o and S u z u k i ( 3 4 ) . They c a n be s a f e l y u s e d w i t h no t o x i c i t y t o man, l i v e s t o c k , f i s h and p l a n t . Such e x c e l l e n t c h a r a c t e r i s t i c s may be due t o t h e f a c t t h a t p o l y o x i n s s e l e c t i v e l y i n h i b i t the s y n t h e s i s of c e l l w a l l c h i t i n of s e n s i t i v e f u n g i , as was r e p o r t e d by M i s a t o and h i s c o - w o r k e r s ( 3 5 - 3 8 ) . P o l y o x i n s have b e e n w i d e l y u s e d f o r t h e p r o t e c t i o n a g a i n s t some p a t h o g e n i c f u n g i

s u c h a s Altemaria miyabeanus

kikuohiana,

i n Japan s i n c e

Pellioularia

sasakii, and

Coehlibolus

1967.

1) C h e m i s t r y and mode o f a c t i o n : S t r u c t u r e s o f a l l p o l y o x i n s were g i v e n by I s o n o et al. (39) a s d e p i c t e d i n F i g u r e 3. Among p o l y o x i n s , C component i s t h e s m a l l e s t , and t h o u g h i t l a c k s a n t i f u n g a l a c t i v i t y i t was a k e y compound t o e l u c i d a t e t h e s t r u c t u r e of p o l y o x i n s s i n c e h y d r o l y t i c degradation of a l l the p o l y o x i n s afforded p o l y o x i n C or i t s analogues. I s o n o and S u z u k i (40) assigned the s t r u c t u r e , l-ft-iS'-amino-S'-deoxy-D-allofuranuronosyl) - 5 - h y d r o x y m e t h y l u r a c i l t o p o l y o x i n C by c h e m i c a l and p h y s i c a l t e c h n i q u e s , and a s i n g l e - c r y s t a l X - r a y d i f f r a c t i o n a n a l y s i s o f Nb r o s y l p o l y o x i n C c o n f i r m e d the s t r u c t u r e (41). T h i s prompted the t o t a l s y n t h e s i s o f p o l y o x i n J by K u z u h a r a et al. ( 4 2 ) . In s t u d y i n g t h e mechanism o f f u n g i c i d a l a c t i o n o f p o l y o x i n s , E g u c h i et al. (43) o b s e r v e d a s p e c i f i c p h y s i o l o g i c a l a c t i o n a g a i n s t Altevnaria spp. i n i n h i b i t i n g i t s g r o w t h ; p o l y o x i n s c a u s e d m a r k e d a b n o r m a l b u l b o u s phenomenon on germ t u b e s o f s p o r e and h y p h a l t i p s o f t h e p a t h o g e n a t l o w c o n c e n t r a t i o n , and t h i s a b n o r m a l l y s w o l l e n s p o r e became n o n - i n f e c t i o u s . I t was a l s o r e p o r t e d t h a t t h e


10.

MisATO

Agricultural

177

Antibiotics

Ο

Ri


Polyoxin

R

2

A

CH OH

*

OH

Β

CH 0H

HO

OH

D

COOH

HO

OH

Ε

COOH

HO

Η

F

COOH

*

OH

6

CH 0H 2

HO

H

H

CH

a

*

OH

J

CH

3

HO

OH

Κ

H

*

OH

L

H

HO

OH

M

H

HO

H

2

2

COOH

R

Figure 3.

R3

C

HO

I

COOH

Structure of polyoxins


178


THE

20TH

CENTURY


lz

i n c o r p o r a t i o n of *C-glucosamine i n t o c e l l w a l l c h i t i n of Coohliobolus miyabeanus was m a r k e d l y i n h i b i t e d by p o l y o x i n D, w i t h o u t i n h i b i t o r y e f f e c t on r e s p i r a t i o n and s y n t h e s i s o f m a c r o m o l e c u l e s s u c h as p r o t e i n o r n u c l e i c a c i d s ( 4 4 ) . Endo and M i s a t o (36) showed i n t h e i r k i n e t i c s t u d i e s o f t h e c e l l - f r e e s y s t e m o f Neurospora arassa t h a t p o l y o x i n D s t r o n g l y i n h i b i t s t h e i n c o r p o r a t i o n of N - a c e t y l g l u c o s a m i n e (GlcNAc) i n t o c h i t i n i n c o m p e t i t i v e manner b e t w e e n UDP-GlcNAc and p o l y o x i n D. More r e c e n t l y H o r i et at. (38) r e p o r t e d t h e r e l a t i o n b e t w e e n p o l y o x i n s t r u c t u r e and i n h i b i t o r y a c t i v i t y on c h i t i n s y n t h e t a s e . According to t h e i r k i n e t i c a n a l y s i s , the carbamoyl polyoxamic a c i d moiety of p o l y o x i n s w o u l d h e l p t o s t a b i l i z e t h e p o l y o x i n enzyme c o m p l e x and the p y r i m i d i n e n u c l e o s i d e moiety of the a n t i b i o t i c s would a l s o f i t i n t o b i n d i n g s i t e of the p r o t e i n . Therefore the e x c e l l e n t c h a r a c t e r i s t i c s o f p o l y o x i n s may be due t o t h e f a c t t h a t t h e a n t i b i o t i c s i n h i b i t the c e l l w a l l s y n t h e s i s of s e n s i t i v e f u n g i but have no i n f l u e n c e on o t h e r o r g a n i s m s i n c l u d i n g mammals, s i n c e t h e r e e x i s t no c e l l w a l l s i n a n i m a l c e l l s . 2) B i o l o g i c a l p r o p e r t i e s : P o l y o x i n s i n h i b i t t h e g r o w t h o f some f u n g i b u t a r e i n a c t i v e a g a i n s t b a c t e r i a and y e a s t . A l l the p o l y o x i n s e x c e p t C and I showed s e l e c t i v e a n t i f u n g a l a c t i v i t y a g a i n s t v a r i o u s p l a n t p a t h o g e n i c f u n g i ( 4 5 ) . Among p o l y o x i n s , p o l y o x i n D was most e f f e c t i v e f o r r i c e s h e a t h b l i g h t p a t h o g e n , Pellicularia sasakii, w h e r e a s Β and L w e r e e f f e c t i v e f o r p e a r s p o t f u n g u s and a p p l e c o r k s p o t f u n g u s a t 50 t o 100 ppm. Polyoxin c o m p l e x has b e e n u s e d i n p r a c t i c e i n d u p l i c a t e f o r m s ; p o l y o x i n D r i c h f r a c t i o n f o r t h e s h e a t h b l i g h t c o n t r o l , and Β r i c h f r a c t i o n f o r d i s e a s e s c a u s e d by Altemaria spp. As f o r i t s t o x i c i t y , o r a l a d m i n i s t r a t i o n a t 15 g/kg and i n j e c t i o n a t 800 mg/kg t o m i c e d i d n o t c a u s e any a d v e r s e e f f e c t , n o r i s i t t o x i c t o f i s h d u r i n g 72 h o u r s p e r i o d o f e x p o s u r e a t 10 ppm. M o r e o v e r , f o l i a r s p r a y s o f 200 ppm p o l y o x i n s have p r o d u c e d no p h y t o t o x i c i t y on most c r o p s , and e s p e c i a l l y on r i c e p l a n t no i n j u r y was o b s e r v e d e v e n a t 800 ppm a p p l i c a t i o n ( 3 3 , 4 6 ) . R e c e n t l y , N i s h i m u r a et at. (47) h a v e r e p o r t e d t h e d i s c o v e r y o f p o l y o x i n r e s i s t a n t s t r a i n s o f A. kikuohiana i n some o r c h a r d s o f T o t t o r i P r e f e c t u r e , J a p a n . H o r i et al. (48) s u g g e s t e d t h a t t h e r e s i s t a n c e i s c a u s e d by a l o w e r e d p e r m e a b i l i t y o f t h e a n t i b i o t i c t h r o u g h t h e c e l l membrane i n t o t h e s i t e o f c h i t i n s y n t h e s i s . M i t a n i and I n o u e (49) f o u n d t h a t t h e i n h i b i t i o n o f m y c e l i a l g r o w t h o f P. sasakii, by p o l y o x i n s was p r o t e c t e d by g l y c y l - L a l a n i n e , g l y c y l - D , L - v a l i n e and D , L - a l a n y l g l y c i n e . T h e r e f o r e , t h e p e p t i d e s may a c t a s a n t a g o n i s t s t o t h e i n c o r p o r a t i o n o f p o l y o x i n s i n t o the c e l l of the fungus. Validamycin. V a l i d a m y c i n A (VM-A) i s a new a n t i f u n g a l a n t i b i o t i c r e c e n t l y developed i n Japan f o r the c o n t r o l of r i c e sheath b l i g h t (50-52). I t was i s o l a t e d f r o m t h e c u l t u r e f i l t r a t e o f Streptomyaes hygroscopicus v a r . limoneus, w h i c h a l s o p r o d u c e d f i v e


10.

MisATO

Agricultural

Antibiotics

179


a d d i t i o n a l components d e s i g n a t e d v a l i d a m y c i n Β t o F, t o g e t h e r w i t h v a l i d o x y l a m i n e A and Β (52,53). VM-A c a n be u s e d w i t h o u t i n j u r y t o p l a n t s , and w i t h v e r y l o w t o x i c i t y t o mammals ( 5 4 ) . A l m o s t no t o x i c i t y was a l s o o b s e r v e d f o r b i r d s , f i s h and i n s e c t s . 1) C h e m i s t r y and mode o f a c t i o n : The c h e m i c a l s t r u c t u r e o f v a l i d a m y c i n A was d e t e r m i n e d b y H o r i i , Kameda and t h e i r c o - w o r k e r s t o be N - [ ( l s ) - ( l , 4 , 6 / 5 ) - 3 - h y d r o x y m e t h y l - 4 , 5 , 6 - t r i h y d r o x y c y c l o h e x - 2 enyl][Ο-β-D-glucopyranosyl-(l->3 ) - ( l s ) - ( l , 2 , 4 / 3 , 5 ) - 2 , 3 , 4 - t r i h y d r o x y - 5 - h y d r o x y m e t h y l c y c l o h e x y l ] amine a s shown i n F i g u r e 4 (53,55,56,57). As f o r mode o f a c t i o n o f v a l i d a m y c i n A, Wakae and M a t s u u r a ( 5 8 ) showed t h a t VM-A i n h i b i t s b i o s y n t h e s i s o f i n o s i t o l i n P . sasakii, and t h e y s u p p o s e d t h a t i n o s i t o l may be i n d i s p e n s a b l e f o r t h e n o r m a l g r o w t h and p a t h o g e n i c a c t i v i t y o f t h e f u n g u s . A l t h o u g h r e d u c t i o n o f p a t h o g e n i c i t y i n d u c e d b y VM-A was remarkably r e c o v e r e d by t h e p r e m i x i n g o f i n o s i t o l i n t h e i r e x p e r i ment, f u r t h e r i n v e s t i g a t i o n w i l l be r e q u i r e d t o s o r t o u t t h e s p e c i f i c s i t e a n d t y p e o f a c t i o n o f VM-A. 2) B i o l o g i c a l p r o p e r t i e s : A n t i m i c r o b i a l a c t i v i t y o f VM-A a g a i n s t a b o u t 3,000 s p e c i e s o f f u n g i and b a c t e r i a was n o t d e t e c t e d w i t h o r d i n a r y methods ( 5 1 , 5 9 ) , a n d a l s o d i s t u r b a n c e o f m i c r o f l o r a on r i c e p l a n t a n d c r o p f i e l d was n o t o b s e r v e d ( 5 8 ) . Wakae a n d M a t s u u r a (60) f o u n d no p h y t o t o x i c i t y o n o v e r 150 s p e c i e s o f p l a n t s s p r a y e d w i t h VM-A e v e n a t a c o n c e n t r a t i o n o f 1,000 ppm. Further more, a c u t e a n d s u b a c u t e t o x i c i t i e s t o mammals w e r e m a r k e d l y l o w ; i n o r a l a d m i n i s t r a t i o n o f v a l i d a m y c i n A a t t h e d o s e o f 10 g/kg t o m i c e and r a t s , o r i n s u b c u t a n e o u s and i n t r a v e n o u s a d m i n i s t r a t i o n a t t h e d o s e o f 2 g/kg t o m i c e , a l l a n i m a l s e x a m i n e d s u r v i v e d w i t h o u t any change f o r 7 days ( 5 1 ) . VM-A i s a m a i n component o f v a l i d a m y c i n c o m p l e x and i s s p e c i f i c a l l y e f f e c t i v e a g a i n s t c e r t a i n p l a n t d i s e a s e s c a u s e d b y Rhizoctonia s p p . , s u c h a s web b l i g h t , b u d r o t , d a m p i n g - o f f s e e d d e c a y , r o o t r o t and b l a c k s c u r f o f s e v e r a l c r o p s and s o u t h e r n b l i g h t o f v e g e t a b l e s a s w e l l a s s h e a t h b l i g h t o f r i c e p l a n t ( 5 8 ) . Though t h e a n t i b i o t i c showed n e i t h e r c i d a l n o r s t a t i c a c t i o n o f Rhizoctonia s p p . , i t c a u s e d an a b n o r m a l b r a n c h i n g a t t h e t i p s o f hyphae o f t h e p a t h o g e n , f o l l o w e d b y c e s s a t i o n o f f u r t h e r d e v e l o p m e n t ( 5 1 ) . When i t was a p p l i e d i n t h e e a r l y l o g a r i t h m i c p h a s e o f l e s i o n e x p a n s i o n on r i c e p l a n t , s u f f i c i e n t c o n t r o l was a c h i e v e d b y one s p r a y i n g o f 30 ppm VM-A s o l u t i o n ( 6 0 ) . VM-A h a s b e e n c o m m e r c i a l l y u s e d upon s h e a t h b l i g h t d i s e a s e s i n c e 1973. V a l i d a m y c i n s h a v e b e e n shown t o be s u s c e p t i b l e t o m i c r o b i a l a t t a c k and t h e i r a d d i t i o n t o s o i l r e s u l t ed i n c o m p l e t e l o s s o f b i o l o g i c a l a c t i v i t y b y s o i l m i c r o b e s . I t s h a l f - l i f e i n s o i l was l e s s t h a n 4 h o u r s . M i c r o b i a l degrada t i o n o f VM-A b y Pseudomonas denitrificans gave r i s e t o D - g l u c o s e and v a l i d o x y l a m i n e A, w h i c h was f u r t h e r decomposed i n t o v a l i e n a m i n e , v a l i d a m i n e and o t h e r l o w e r compounds ( 6 1 ) . V a l i d a m y c i n A has been p r a c t i c a l l y used t o p r o t e c t sheath b l i g h t o f r i c e p l a n t i n t h e f o r m u l a t i o n s o f 3 % s o l u t i o n o r 0.3 % d u s t .


180



Figure 5.

Structure of ezomycin


10.

MisATO

Agricultural

181

Antibiotics


R e s i d u e s i n r i c e g r a i n s and s t r a w s w e r e l e s s t h a n e a c h l i m i t by gas c h r o m a t o g r a p h y ( 6 2 ) .

detectable

Ezomycins. E z o m y c i n s a r e a n t i f u n g a l a n t i b i o t i c s p r o d u c e d by a s t r a i n o f Streptomyces v e r y s i m i l a r t o S. kitazawaensis. T a k a o k a et al. (63) i s o l a t e d a c o m p l e x o f t h e a n t i b i o t i c s f r o m t h e c u l t u r e f i l t r a t e o f t h e p r o d u c i n g o r g a n i s m and r e p o r t e d t h a t t h e c o m p l e x has u n i q u e b i o l o g i c a l a c t i v i t y i n s u p p r e s s i n g the g r o w t h o f v e r y l i m i t e d s p e c i e s o f p h y t o p a t h o g e n i c f u n g i , s u c h as Sclerotica and Botrytis spp. S i n c e t h e c o m p l e x showed r e m a r k a b l e a n t i m i c r o b i a l a c t i v i t y a g a i n s t Sclerotinia sclerotiorvm de B a r y t h a t c a u s e s s t e m r o t i n k i d n e y b e a n p l a n t s (Phaseolus vulgaris L.), i s o l a t i o n and c h a r a c t e r i z a t i o n o f e a c h component o f e z o m y c i n s w e r e c a r r i e d o u t by S a k a t a et al. (64). According to Sakata et al. e z o m y c i n s a r e new p y r i m i d i n e n u c l e o s i d e s , and t h e p r e s e n c e of L - c y s t a t h i o n i n e i n ezomycin molecule i s r e s p o n s i b l e f o r specific antifungal activity. Recently they e l u c i d a t e d the c h e m i c a l s t r u c t u r e o f a l l t h e e z o m y c i n s (65-67) ; F i g u r e 5 shows t h e c h e m i c a l s t r u c t u r e o f e z o m y c i n A. T h i s a n t i b i o t i c was registered a s an a g r i c u l t u r a l a n t i b i o t i c f o r t h e c o n t r o l o f s t e m r o t o f k i d n e y b e a n i n 1970, b u t has s c a r c e l y b e e n on t h e m a r k e t since then. 9

Antibacterial

antibiotic

Cellocidin. C e l l o c i d i n i s an a n t i b i o t i c p r o d u c e d f r o m Streptomyces chibaensis (68,69). I t i s an a c e t y l e n e d i c a r b o x y a m i d e c o n t a i n i n g o n l y f o u r c a r b o n atoms as shown i n F i g u r e 6. As i t s c h e m i c a l s t r u c t u r e i s so s i m p l e , i t i s e a s y t o s y n t h e s i z e chemically. T e c h n i c a l grade c e l l o c i d i n f o r commercial formula t i o n s i s now s y n t h e s i z e d f r o m f u m a r i c a c i d o r b u t y n e d i o l . C e l l o c i d i n shows an e x c e l l e n t p r e v e n t i v e e f f e c t a g a i n s t r i c e bacterial l e a f b l i g h t when s p r a y e d on r i c e p l a n t s a t 100 t o 200 ppm ( 7 0 ) . I t s t o x i c i t y when i n j e c t e d i n t r a v e n o u s l y i s h i g h ( L D o t o m i c e , l l m g / k ^ ) , b u t i n o r a l a d m i n i s t r a t i o n and s k i n a p p l i c a t i o n i t i s n o t so h i g h l y t o x i c ( L D t o m i c e , 89.2 - 125 mg/kg and L D o t o m i c e , 667 mg/kg r e s p e c t i v e l y ) . C e l l o c i d i n has b e e n p r a c t i c a l l y u s e d s i n c e 1964. However, i t s c o n s u m p t i o n has b e e n r e m a r k a b l y d e c r e a s e d due t o i t s p h y t o t o x i c i t y . The a n t i b a c t e r i a l a c t i o n o f c e l l o c i d i n was a n t a g o n i z e d by c y s t e i n e o r g l u t a t h i o n e , w h i c h i n d i c a t e s i n t e r a c t i o n w i t h SH-groups. A s t u d y of s e v e r a l m e t a b o l i c s y s t e m s f r o m Xanthomonas oryzae r e v e a l e d that c e l l o c i d i n s e l e c t i v e l y i n h i b i t e d N A D - r e q u i r i n g d e h y d r o g e n a s e , and e s p e c i a l l y i n t h e p a t h w a y f r o m α-ketoglutamic a c i d t h r o u g h s u c c i n y l Co A t o s u c c i n i c a c i d a t t h e minimum g r o w t h i n h i b i t o r y c o n c e n t r a t i o n o f 10 ppm (71). 5

5 0

Insecticidal

5

antibiotic

Tetranactin.

T e t r a n a c t i n , a new

miticidal antibiotic,


was

PESTICIDE

C H E M I S T R Y I N T H E 20TH

C —CONH,

111

C —C0NH

Structure of cellocidin


Figure 6.

2

Figure 7.

Structure of tetranactin


CENTURY

10.

MisATO

Agricultural

Antibiotics

183


i s o l a t e d as c r y s t a l l i n e rhombic prisms from the f i l t e r cake o f t h e f e r m e n t e d b r o t h o f Streptomyces aureus s t r a i n S-3466 ( 7 2 ) . The a n t i b i o t i c exerted remarkable p e s t i c i d a l a c t i v i t y s p e c i f i c a l l y a g a i n s t t h e a d u l t s o f c a r m i n e m i t e a n d showed v e r y weak t o x i c i t y to a warm-blooded a n i m a l . A l s o i t showed no p h y t o t o x i c i t y t o a p p l e , m a n d a r i n o r a n g e a n d t e a , when s p r a y e d a t h i g h c o n c e n t r a t i o n (73) . The m i t i c i d a l p r o p e r t y o f t e t r a n a c t i n i n t h e f i e l d s o f a p p l e a n d t e a h a d b e e n e v a l u a t e d i n J a p a n s i n c e 1968, a n d t e t r a n a c t i n h a s been used a s a m i t i c i d e f o r p l a n t s s i n c e 1974. 1) C h e m i s t r y a n d mode o f a c t i o n : Ando et al. (72) i s o l a t e d the a c t i v e p r i n c i p l e i n c r y s t a l l i n e form by e x t r a c t i n g t h e m y c e l i a l c a k e o f S. aureus w i t h acetone followed by s i l i c a g e l c o l u m n c h r o m a t o g r a p h y . They a l s o showed t h a t S. aureus produces, a l o n g w i t h t e t r a n a c t i n , two o t h e r s t r u c t u r a l l y r e l a t e d m a c r o t e t r o l i d e a n t i b i o t i c s , i . e . , d i n a c t i n and t r i n a c t i n , i n minor amount. From t h e s t u d i e s o n t h e c h e m i c a l c h a r a c t e r i s t i c s o f t e t r a n a c t i n , i t was f o u n d t h a t t h e a n t i b i o t i c a l s o b e l o n g s t o t h e c l a s s o f m a c r o t e t r o l i d e a n t i b i o t i c and i s a c y c l i c p o l y e s t e r composed o f f o u r u n i t s o f h o m o n o n a c t i c a c i d , a s shown i n F i g u r e 7 (74) • The s t e r e o c h e m i c a l s t r u c t u r e was c l a r i f i e d w i t h t h e u s e o f X - r a y c r y s t a l l o g r a p h y b y I i t a k e et al. (75). A s f o r mode o f a c t i o n o f t e t r a n a c t i n , Ando et al. (76) o b s e r v e d t h a t t e t r a n a c t i n i s an u n c o u p l e r i n c o c k r o a c h m i t o c h o n d r i a and supposed t h a t t h e a n t i b i o t i c caused t h e leakage o f a l k a l i c a t i o n s such as K through t h e l i p i d l a y e r o f t h e biomembrane i n m i t o c h o n d r i a , f o l l o w e d b y uncoupling. +

2) B i o l o g i c a l p r o p e r t i e s : S p e c i f i c i t y i n b i o l o g i c a l a c t i v i t y i s a unique property o f t e t r a n a c t i n ; i t exerted potent p e s t i c i d a l a c t i v i t y a g a i n s t the a d u l t s o f a carmine s p i d e r m i t e a l o n e , L D o f o r w h i c h i s 4.8 y g / m l w i t h t h e s p r a y method ( 7 7 ) . A z u k i b e a n w e e v i l and l a r v a o f m o s q u i t o were m o d e r a t e l y s e n s i t i v e to the a n t i b i o t i c , w h i l e o t h e r p e s t s such a s house f l y and c o c k r o a c h w e r e i n s e n s i t i v e . I n a d d i t i o n , i t was o b s e r v e d t h a t t h e o v i c i d a l a c t i v i t y o f the a n t i b i o t i c a g a i n s t t h e s e n s i t i v e m i t e s i s n o t s o s i g n i f i c a n t , w h i c h a p p e a r e d t o b e one o f t h e weak p o i n t s o f tetranactin. The m i t i c i d a l a c t i v i t y , h o w e v e r , was c o n f i r m e d i n the t r i a l s . T e t r a n a c t i n s u s p e n s i o n s were s p r a y e d on a p p l e t r e e s on w h i c h l e a v e s Kanzawa s p i d e r and European r e d m i t e were n a t u r a l l y p a r a s t i c ; p r o l i f e r a t i o n o f b o t h m i t e s were c o m p l e t e l y retarded d u r i n g 32 d a y s o f t h e e x p e r i m e n t . Another c h a r a c t e r i s t i c o f tetranactin i s i t s safety. Ando et al. (72) r e p o r t e d t h a t m i c e t o l e r a t e d a n i n t r a p e r i t o n e a l a d m i n i s t r a t i o n o f 300 mg/kg a n d a n o r a l a d m i n i s t r a t i o n o f 15 g/kg. They a l s o o b s e r v e d t h a t a c u t e t o x i c i t y o f t h e a n t i b i o t i c i s v e r y l o w ; t h e o r a l L D s o ' s a r e more t h a n 2 g/kg t o r a t s , g u i n e a p i g s , q u a i l s a n d r a b b i t s ( 7 6 ) . They suggested that t h e low t o x i c i t y i s p a r t l y a t t r i b u t a b l e t o t h e poor a b s o r p t i o n by a n i m a l s . When C - t e t r a n a c t i n p r e p a r e d b y b i o s y n t h e s i s was a d m i n i s t e r e d o r a l l y t o m i c e , i t was r e v e a l e d t h a t 5

1 4


184


THE

20TH

t h e a n t i b i o t i c i s l i t t l e a b s o r v e d so t h a t t h e d i s t r i b u t i o n v a r i o u s o r g a n s was n e g l i g i b l e and a l m o s t a l l r a d i o a c t i v i t y r e c o v e r e d i n f e c e s 72 h o u r s a f t e r a d m i n i s t r a t i o n ( 7 6 ) . Other promising

CENTURY

in was

antibiotics


1. H e r b i c i d a l a n t i b i o t i c M e t h o x y p h e n o n e (An a n i s o m y c i n a n a l o g u e ) . Yamada et αϊ· (78) f o u n d a s t r a i n o f Streptomyoes t o p r o d u c e two p l a n t - r e g u l a t i n g s u b s t a n c e s , w h i c h w e r e l a t e r i d e n t i f i e d as a n i s o m y c i n (79) and toyokamycin (80). They o b s e r v e d t h a t a n i s o m y c i n e x e r t e d s t r o n g g r o w t h - i n h i b i t o r y a c t i v i t y on t h e r o o t s and s h o o t s o f a l l t h e p l a n t s t e s t e d ( r i c e , b a r n y a r d g r a s s , c r a b g r a s s , l u c e r n e and t o m a t o ) a t 12.5 and 50 ppm, r e s p e c t i v e l y . T h e s e r e s u l t s l e d t o t h e i n v e s t i g a t i o n o f compounds h a v i n g p - m e t h o x y p h e n y l groups(pa n i s o l e d e r i v a t i v e s ) on p l a n t g r o w t h - r e g u l a t i n g a c t i v i t y , and many a n i s o l e d e r i v a t i v e s w e r e s y n t h e s i z e d and t h e i r a c t i v i t i e s w e r e t e s t e d (81). T h i s r e s u l t e d i n the f i n d i n g of i n t e r e s t i n g p l a n t g r o w t h - r e g u l a t i n g a c t i v i t i e s o f p - m e t h o x y d i p h e n y l m e t h a n e s and p-methoxybenzophenones. E s p e c i a l l y , r e m a r k a b l e h e r b i c i d a l a c t i v i t y was c o n f i r m e d f o r 3 , 3 - d i m e t h y l - 4 - m e t h o x y b e n z o p h e n o n e (methoxyphenone) i n t h e paddy f i e l d t e s t s . M e t h o x y p h e n o n e c o m p l e t e l y i n d u c e d c h l o r o s i s i n b a r n y a r d g r a s s and p r o v i d e d a s a t i s f a c t o r y h e r b i c i d a l e f f e c t a t 4 kg/ha a p p l i c a t i o n , a l t h o u g h weak c h l o r o s i s was o c c a s i o n a l l y o b s e r v e d i n r i c e s t e m a t 6 k g / h a (82). A c c o r d i n g t o I s h i d a et al., methoxyphenone i s q u i t e a s t a b l e s u b s t a n c e , b u t i s g r a d u a l l y decomposed by s u n l i g h t . In paddy f i e l d , i t a l s o seems t o be s u s c e p t i b l e t o m i c r o b i a l a t t a c k ; c o n c e n t r a t i o n o f methoxyphenone i n t h e s o i l r e a c h e d a max 2.16 ppm 7 days a f t e r a p p l i c a t i o n , b u t d e c r e a s e d t o 0.018 ppm a f t e r 30 d a y s and t o b e l o w 0.004 ppm a f t e r 60 d a y s . W h i l e t h e m e t a b o l i c f a t e o f methoxyphenone i n t h e e n v i r o n m e n t i s p r e s e n t l y u n d e r i n v e s t i g a t i o n , t h i r t e e n m e t a b o l i t i e s h a v e so f a r b e e n i d e n t i f i e d ; t h e m e t h o x y g r o u p was t r a n s f o r m e d i n t o t h e h y d r o x y g r o u p and t h e b e n z o p h e n o n e s k e l e t o n was decomposed t o w - t o l u i c a c i d and 4-hydroxy-/7?-toluic a c i d . I n a d d i t i o n , the acute t o x i c i t y of methoxyphenone t o m i c e and r a t s was f o u n d t o be more t h a n 4 g/kg independent of the a d m i n i s t r a t i o n routes (82). Therefore, m e t h o x y p h e n o n e i s c o n s i d e r e d t o be a p r o m i s i n g h e r b i c i d e w i t h a h i g h l e v e l o f s a f e t y f o r use i n the e n v i r o n m e n t . 1

2. A n t i v i r a l a n t i b i o t i c s One o f t h e most s e r i o u s p r o b l e m s on p l a n t d i s e a s e c o n t r o l i s the v i r u l e n c e of v i r u s d i s e a s e s . T r i a l s to develop a n t i v i r a l a n t i b i o t i c s h a v e b e e n e n t h u s i a s t i c a l l y c o n d u c t e d by many w o r k e r s . C o n s e q u e n t l y , many a n t i b i o t i c s h a v e b e e n r e v e a l e d t o be e f f e c t i v e on i n h i b i t i n g t h e m u l t i p l i c a t i o n o f s e v e r a l p l a n t v i r u s e s by in vitro t e s t and p o t t e s t . They a r e b l a s t i c i d i n S, l a u r u s i n , b i h o r o m y c i n , m i h a r a m y c i n , c i t r i n i n and a a b o m y c i n A e t c . However,


10.

MisATO

Agricultural

Antibiotics

t h e r e i s no a n t i b i o t i c virus diseases. A a b o m y c i n A. Streptomyces

hygros

185

used p r a c t i c a l l y for c o n t r o l l i n g any p l a n t

A a b o m y c i n A was i s o l a t e d f r o m c u l t u r e b r o t h o f copious

v a r . aabomyoeticus

by

Aizawa

et

at.


( 8 3 ) . By Y a m a g u c h i et al. (84) w i t h l e a f d i s c d i p p i n g method, a a b o m y c i n A showed a b o u t 80 % i n h i b i t i o n o n TMV m u l t i p l i c a t i o n i n tobacco t i s s u e s . Aabomycin A i s n o t o n l y e f f e c t i v e t o i n h i b i t t h e d i s e a s e d e v e l o p m e n t o f TMV, b u t a l s o e f f e c t i v e t o i n h i b i t t h a t o f CMV a n d AMV e t c . , w i t h p o t t e s t . Future prospects One o f t h e g r e a t e s t needs i n t h e p r e s e n t w o r l d i s p r o d u c t i o n o f food f o r b i l l i o n s o f people. A t p r e s e n t , such p r o d u c t i o n r e q u i r e s the use o f p e s t i c i d e s , b u t i n t u r n , t h i s u s e b r i n g s about t h e p o s s i b i l i t y o f environmental p o l l u t i o n . Environmental hazards caused by c o n v e n t i o n a l a g r i c u l t u r a l chemicals a r e c l a s s i f i e d i n t o two c a t e g o r i e s ; a. n o n - s e l e c t i v e t o x i c i t y ( p a r a t h i o n ) a n d b. c o n c e n t r a t i o n a n d a c c u m u l a t i o n o f t o x i c compounds i n t h e e n v i r o n ment (DDT a n d BHC). P o l l u t i o n f r e e p e s t i c i d e s , t h e r e f o r e , s h o u l d have s e l e c t i v e t o x i c i t y t o t a r g e t o r g a n i s m s a n d b e s e n s i t i v e f o r p h o t o l y s i s a n d d e g r a d a t i o n b y s o i l m i c r o o r g a n i s m s . From t h e s e v i e w p o i n t s , a n t i b i o t i c s may b e presumed t o b e u s e f u l b i o d e g r a d a b l e pesticides. As i s t r u e f o r every s c i e n t i f i c technique, t h e use of a g r i c u l t u r a l a n t i b i o t i c s a l s o has i t s advantages and limitations. The a d v a n t a g e s . 1) S e l e c t i v e t o x i c i t y t o t a r g e t o r g a n i s m s : S i n c e most a n t i b i o t i c s have s e l e c t i v e t o x i c i t y t o t a r g e t organisms and l o w t o x i c i t y t o mammals a s shown i n T a b l e I I I , t h e y c a n b e s a f e l y u s e d w i t h o u t h a r m i n g man, l i v e s t o c k , f i s h a n d c r o p s . Mode o f a c t i o n o f a g r i c u l t u r a l a n t i b i o t i c s a r e summarized i n T a b l e ÏV. Table I I I . Antibiotic

T o x i c i t y o f a n t i b i o t i c s t o animals Animal

Acute o r a l t o x i c i t y ( L D o mg/kg) 5

Blasticidin S Kasugamycin Polyoxins Validamycin Tetranactin

Rat Mouse Mouse Mouse Mouse

53.3 20,900 15,000 10,000 15,000


PESTICIDE C H E M I S T R Y IN T H E 2 0 T H

186

Table IV.

Mode o f a c t i o n o f a n t i b i o t i c Primary action

Antibiotic


Polyoxins Tetranactin Validamycin Blasticidin S Kasugamycin Cycloheximide Streptomycin Cellocidin Griseofulvin

CENTURY

site

C h i t i n synthesis of c e l l w a l l C a t i o n leakage from m i t o c h o n d r i a Biosynthesis of i n o s i t o l

• Protein synthesis * -ι j

DNA s y n t h e s i s

2) E a s y d e g r a d a t i o n b y s o i l m i c r o o r g a n i s m s : A n t i b i o t i c s p r o d u c e d b y m i c r o o r g a n i s m s w o u l d be r a p i d l y d e g r a d e d b y s o i l microorganisms. A f t e r a p p l i c a t i o n t o the crop, a n t i b i o t i c s might be r a p i d l y b r o k e n down i n t h e e n v i r o n m e n t , so t h a t t h e r e may be no d a n g e r o f e n v i r o n m e n t a l p o l l u t i o n and f o o d c o n t a m i n a t i o n . 3) S m a l l amount o f compound u s e d i n a u n i t a r e a : S i n c e a g r i c u l t u r a l a n t i b i o t i c s a r e sprayed a t v e r y l o w c o n c e n t r a t i o n as shown i n T a b l e V, t h e amount o f compounds s p r a y e d i n a u n i t a r e a i s f a r l e s s (1/10 - 1/100) t h a n t h a t o f o t h e r c o n v e n t i o n a l p e s t i c i d a l c h e m i c a l s . A l s o a n t i b i o t i c s w o u l d be r a p i d l y d e g r a d e d by s o i l m i c r o o r g a n i s m s . T h e r e f o r e , i t i s expected t h a t the use of a g r i c u l t u r a l a n t i b i o t i c s does n o t b r i n g about t h e p o s s i b i l i t y o f environmental p o l l u t i o n . T a b l e V.

The c o n c e n t r a t i o n o f a n t i b i o t i c f o r a p p l i c a t i o n

Antibiotic Cycloheximide Blasticidin S Kasugamycin Validamycin Tetranactin Polyoxins Streptomycin [Other f u n g i c i d e s ] O r g a n i c p h o s p h o r u s compounds O r g a n i c s u l f u r compounds I n o r g a n i c s u l f u r compounds B o r d e a u x m i x t u r e (CuSO/,)

Concentration 2 10 20 30 100 100 100

(ppm)

- 3 - 20 - 40 - 50 - 130 - 200 - 200

500 1,000 - 1,500 2,000 4,000


10.

MisATO

Agricultural

Antibiotics

187

4) M a n u f a c t u r e o f b i o - a c t i v e compounds w i t h c o m p l e x c h e m i c a l s t r u c t u r e s : N o v e l b i o - a c t i v e compounds w i t h v e r y c o m p l e x c h e m i c a l s t r u c t u r e s w h i c h a r e o u t s i d e t h e domain o f o r g a n i c s y n t h e s i s , c a n be i s o l a t e d a n d m a n u f a c t u r e d on a c o m m e r c i a l b a s i s .


5) F a v o r a b l e i n v e s t m e n t i n e q u i p m e n t : V a r i o u s a n t i b i o t i c s can be p r o d u c e d b y u s i n g a s i n g l e s e t o f e q u i p m e n t a n d f a c i l i t i e s . T h i s advantage b r i n g s about l o w i n i t i a l c o s t o f a n t i b i o t i c s . 6) U t i l i z a t i o n o f s o l a r e n e r g y : A n t i b i o t i c s a r e p r o d u c e d b y u t i l i z i n g a g r i c u l t u r a l products which are obtained from b i o l o g i c a l p h o t o s y n t h e t i c c o n v e r s i o n o f s o l a r e n e r g y . The p r o d u c t i o n o f a n t i b i o t i c s does n o t much consume t h e s t o r e d e n e r g y s u c h a s o i l and coal. The

limitations.

1) D i f f i c u l t y f o r a n a l y s i s i n m i c r o - s c a l e : A n t i b i o t i c s a r e g e n e r a l l y m i x t u r e s o f v a r i o u s s t r u c t u r a l l y r e l a t e d components l i k e polyoxins. This complexity i s a d i f f i c u l t y for analysis i n micros c a l e a n d s a f e t y e v a l u a t i o n o f compounds. 2) R e s i s t a n t o f p l a n t p a t h o g e n s t o a n t i b i o t i c s : T o l e r a n c e or r e s i s t a n c e o f p a t h o g e n i c microorganisms t o a n t i b i o t i c s has occurred shortly after application of a n t i b i o t i c s for the control o f p l a n t d i s e a s e s a s shown i n T a b l e V I . I n order t o reduce o r a v o i d t h e emergence o f t o l e r a n t f u n g i a n d b a c t e r i a i n t h e f i e l d s , the a l t e r n a t e o r combined a p p l i c a t i o n o f c h e m i c a l s w i t h d i f f e r e n t mechanisms o f a c t i o n i s recommended. Table VI. Antibiotic Blasticidin S Kasugamycin Polyoxins Streptomycin

Resistance to a n t i b i o t i c Where n o t e d Laboratory F i e l d and l a b . F i e l d and l a b , F i e l d and l a b .

Major organism Pyricularia Vyricularia Altemaria Xanthomonas

oryzae oryzae kikuchiana oryzae

P u b l i c h e a l t h a s p e c t s . A l i m i t e d number a n d a r e l a t i v e l y s m a l l q u a n t i t y o f m e d i c a l a n t i b i o t i c s have b e e n i n t r o d u c e d i n a g r i c u l t u r a l u s e a s shown i n T a b l e I . M o s t a g r i c u l t u r a l a n t i b i o t i c s have been used o n l y f o r p l a n t p r o t e c t i o n purposes and n o t used i n m e d i c a l treatment. T h e r e f o r e , the p u b l i c ' s concern f o r t h e e n v i r o n m e n t a l p r o b l e m o f a n t i b i o t i c s must b e d i f f e r e n t i n t h e two a r e a s where a n t i b i o t i c s a r e u s e d . A g r i c u l t u r a l a n t i b i o t i c s do not i n v o l v e p r i m a r i l y the h e a l t h o f t h e i n d i v i d u a l , b u t t h e i r u s e has m a c r o e n v i r o n m e n t a l c o n s e q u e n c e s . M o s t human i n f e c t i o u s d i s e a s e s a r e caused by b a c t e r i a and v i r u s e s , w h i l e p l a n t pathogens


188



a r e m o s t l y c l a s s i f i e d a s f u n g i . A c c o r d i n g l y , most m e d i c a l a n t i b i o t i c s a r e e f f e c t i v e a g a i n s t b a c t e r i a , whereas a g r i c u l t u r a l antibiotics aregenerally fungicidal. S e l e c t i v i t y of a g r i c u l t u r a l a n t i b i o t i c a c t i o n can eradicate fungi responsible f o r the target p l a n t d i s e a s e without harming other microorganisms such as b a c t e r i a p a r a s i t i c on humans. A p p l i c a t i o n o f a n t i b i o t i c s f o r the c o n t r o l o f p l a n t p e s t s i s never concerned i n t h e development of r e s i s t a n t microorganisms t o medical a n t i b i o t i c s . Some a n t i b i o t i c s c a n be s y n t h e s i z e d c h e m i c a l l y . I n t h i s respect there i s no d i f f e r e n c e b e t w e e n a n t i b i o t i c s a n d s y n t h e t i c c h e m i c a l s . The problem i s whether an a n t i b i o t i c i s used i n a g r i c u l t u r a l o r i n m e d i c a l use. I t makes no d i f f e r e n c e w h e t h e r i t i s p r o d u c e d b y microorganisms o r synthesized chemically. In t h i s a r t i c l e thepresent status o f a g r i c u l t u r a l a n t i b i o t i c s h a s been d e s c r i b e d . T h e i r development i n Japan h a s b r o u g h t a b o u t s u c c e s s f u l d i s c o v e r i e s o f b l a s t i c i d i n S, k a s u g a m y c i n , p o l y o x i n s and v a l i d a m y c i n . R e c e n t l y , s t u d i e s on a g r i c u l t u r a l a n t i b i o t i c s have n o t been l i m i t e d o n l y t o c o n t r o l l i n g p l a n t p a t h o g e n i c m i c r o o r g a n i s m s , b u t e x t e n d e d w i d e r a n d more a c t i v e l y over the v a r i o u s s u b j e c t s such as u t i l i z a t i o n as a n t i v i r a l agents, i n s e c t i c i d e s , h e r b i c i d e s and p l a n t r e g u l a t o r s . I t i s expected t h a t many p o t e n t i a l a n t i b i o t i c s w i l l be d e v e l o p e d a n d a p p l i e d i n a g r i c u l t u r e i n t h e near f u t u r e .

Literature c i t e d (1) Dekker, J. "Fungicides" V o l . II, 579-635. Academic Press, New York (1969) (2) Dekker, J. (1971), World Rev. Pest. Control 10, 9-23. (3) Thirumalachar, M. J. (1968), Adv. Appl. Microbiol. 10, 313-337. (4) Woodbine, M. (ed.), " A n t i b i o t i c s in A g r i c u l t u r e " , Butterworths, London (1962). (5) Zaumeyer, W. J. " F i r s t International Conference on A n t i b i o t i c s in Agriculture" (National Academy of Sciences -National Research Council pub. 397), pp. 171-196. Washington (1956). (6) Woodcock, D. "Systemic Fungicides", pp. 42-54, Longman, London (1972). (7) Takeuchi, S., Hirayama, K., Ueda, K., Sakai, H., and Yonehara, H. (1958), J. Antibiot., 11A, 1-5. (8) Misato, T., Ishii, I., Asakawa, M., Okimoto, Y., and Fukunaga, K. (1959), Ann. Phytopath. Soc. Japan 24, 302-306. (9) Asakawa, Μ., Misato, T., and Fukunaga, K. (1963), Pesticide and Technique 8, 24-30. (10) Ō t a k e , N., Takeuchi, S., Endō, T., and Yonehara, H. (1966), Agr. Biol. Chem. 30, 132-141. (11) Yonehara, H., and Ō t a k e , Ν. (1966), Tetrahedron Letters, pp. 3785-3791.


10. MISATO Agricultural Antibiotics

189


(12) Seto, H., Yamaguchi, I., Ōtake, Ν., and Yonehara, H. (1966), Tetrahedron Letters, pp. 3793-3799. (13) Seto, H., Yamaguchi, I., Ōtake, Ν . , and Yonehara, H. (1968), Agr. Biol. Chem. 32, 1292-1298. (14) Huang, K. T., Misato, T., and Asuyama, H. (1964), J. Antibiot. 17A, 65-74. (15) Misato, T., Ishii, I., Asakawa, M., Okimoto, Y., and Fukunaga, K. (1961), Ann. Phytopath. Soc. Japan 26, 19-24. (16) Misato, T., Okimoto, Y., Ishii, I., Asakawa, Μ., and Fukunaga, K. (1961), Ann. Phytopath. Soc. Japan 26, 25-30. (17) Coutsogeogopoulos, C. (1969), Fed. Proc. 28, 844. (18) Yukioka, M., Hatayama, T., and Morisawa, S. (1975), Biochim. Biophys. Acta 390, 192-208. (19) Hirai, T., and Shimomura, T. (1965), Phytopathology 55, 391-395. (20) Tanaka, N., Sakagami, Y., Yamaki, H., and Umezawa, H. (1961), J. Antibiot. 14A, 123-126. (21) Sugimoto, T. (1972), Nihon Noson Igakukai Zasshi 21, 316-317. (22) Yamaguchi, I., Takagi, K., and Misato, T. (1972), Agr. Biol. Chem. 36. 1719-1727. (23) Umezawa, H., Okami, Y., Hashimoto, T., Suhara, Y., Hamada, M., and Takeuchi, T. (1965), J. Antibiot. 18, 101-108. (24) Suhara, Y., Maeda, K., and Umezawa, H. (1966), Tetrahedron Letters, pp. 1239-1244. (25) Suhara, Y., Sasaki, F., Maeda, K., Umezawa, H., and Ohno, Μ., (1968), J. Am. Chem. Soc. 90, 6559-6560. (26) Ikekawa, T., Umezawa, H., and I i t a k a , Y. (1966), J. Antibiot. 19, 49-50. (27) Nakajima, M., Shibata, H., Kitahara, K., Takahashi, S., and Hasegawa, A. (1968), Tetrahedron Letters, pp. 2271-2274. (28) Kitahara, K., Takahashi, S., Shibata, H., Kurihara, Ν . , and Nakajima, M. (1969), Agr. Biol. Chem. 33, 748-754. (29) Ishiyama, T., Hara, I., Matsuoka, M., S a i t o , K., Shimada, S., Izawa, R . , Hashimoto, T., Hamada, Μ., Okami, Y., Takeuchi, T., and Umezawa, H. (1965), J. Antibiot. 18, 115-119. (30) Tanaka, Ν . , Yamaguchi, H., and Umezawa, H. (1966), J. Biochem. 60, 429-434. (31) Miura, H., I t o , H., and Takahashi, S. (1975), Ann. Phytopath. Soc. Japan 41, 415-417. (32) Suzuki, S., Isono, K., Nagatsu, J., Mizutani, T., Kawashima, Y., and Mizuno, T. (1965). J. Antibiot. 18A, 131. (33) Isono, K., Nagatsu, J., Kawashima, Y., and Suzuki, S. (1965), Agr. Biol. Chem. 29, 848-854. (34) Isono, K., and Suzuki, S. (1968), Tetrahedron Letters, pp. 1133-1137. (35) Sasaki, S., Ota, N., Eguchi, J., Furukawa, Y., Akashiba, T., Tsuchiyama, T., and Suzuki, S. (1968). Ann. Phytopath. Soc. Japan 34, 272-279. (36) Endo, Α., and Misato, T. (1969), Biochem. Biophys. Res. Commun. 37, 718-722.



190

PESTICIDE CHEMISTRY IN THE 20TH CENTURY

(37) Ohta, Ν . , K a k i k i , Κ., and Misato, T. (1970), Agr. Biol. Chem. 34, 1224-1234. (38) H o r i , Μ., K a k i k i , K., and Misato, T. (1974), Agr. Biol. Chem. 38, 691-698. (39) Isono, K., Asahi, K., and Suzuki, S. (1969), J. Am. Chem. Soc. 91, 7490-7505. (40) Isono, K., and Suzuki, S. (1968), Tetrahedron Letters, pp. 203-208. (41) Asahi, K., Sakurai, T., Isono, K., and Suzuki, S. (1968). Agr. Biol. Chem. 32, 1046-1047. (42) Kuzuhara, H., Ohrui, H., and Emoto, S. (1973), Tetrahedron Letters, pp. 5055-5058. (43) Eguchi, J., Sasaki, S., Ota, Ν . , Akashiba, T., Tsuchiyama, T., and Suzuki, S. (1968), Ann. Phytopath. Soc. Japan 34, 280-288. (44) Sasaki, S., Ohta, N., Yamaguchi, I., Kuroda, S., and Misato, T. (1968), J. Agr. Chem.Soc.Japan 42, 633-638. (45) Suzuki, S., Isono, K., Nagatsu, J., Kawashima, Y., Yamagata, K., Sakai, K., and Hashimoto, K. (1966), Agr. Biol. Chem. 30, 817-819. (46) Isono, K., Nagatsu, J., Kobinata, K., Sakai, K., and Suzuki, S. (1967), Agr. Biol. Chem. 31, 190-199. (47) Nishimura, M., Kohmoto, K., and Udagawa, H. (1973), Rept. Tottori Mycol. Inst. (Japan) 10, 677-686. (48) H o r i , Μ., Eguchi, J., K a k i k i , K., and Misato, T. (1974), J. Antibiot. 27, 260-266. (49) M i t a n i , Μ., and Inoue, Y. (1968), J. Antibiot. 21, 492-496. (50) Iwasa, T., Yamamoto, H., and Shibata, M. (1970), J. Antibiot. 23, 595-602. (51) Iwasa, T., Higashide, E., Yamamoto, H., and Shibata, M. (1971), J. Antibiot. 24, 107-113. (52) Iwasa, T., Kameda, Y., A s a i , M., Horii, S., and Mizuno, K . (1971), J. Antibiot. 24, 119-123. (53) Horii, S., and Kameda, Y. (1972), J. Chem.Soc.Comm., pp. 747-748. (54) Hosokawa, S., Ogiwara, S., and Murata, Y. (1974), J. Takeda Res. Lab. 33, 119-131. (55) H o r i i , S., Iwasa, T., and Kameda, Y. (1971), J. Antibiot. 24, 57-58. (56) H o r i i , S., Iwasa, Y., Mizuta, E., and Kameda, Y. (1971), J. Antibiot. 24, 59-63. (57) Kamiya, K., Wada, Y., Horii, S., and Nishikawa, M. (1971), J. Antibiot. 24, 317-318. (58) Wakae, O., and Matsuura, K. (1974), Proc. 1st Intersectional Congress of IAMS (Science Council of Japan) 3, 620-627. (59) Iwasa, T., Higashide, E., and Shibata, M. (1971), J. Antibiot. 24, 114-118. (60) Wakae, O., and Matsuura, K. (1973), Abstr. 2nd International Congress of Plant Pathology, No. 129 (U.S.A.)



10. MISATO Agricultural Antibiotics

191

(61) Kameda, Y., and Horii, S. (1972), J. Chem. Soc. Comm., pp. 746-747. (62) Kameda, Y., and Yamamoto, K. (1970), Abstr. Ann. Phytopath. Soc. Japan 36, 356. (63) Takaoka, K., Kuwayama, T., and Aoki, A. (1971), Japanese Patent, 615332. (64) Sakata, K., Sakurai, Α., and Tamura, S. (1974), Agr. Biol. Chem. 38, 1883-1890. (65) Sakata, K., Sakurai, Α., and Tamura, S. (1974), Tetrahedron Letters, pp. 4327-4330. (66) Sakata, K., Sakurai, Α., and Tamura, S. (1975), Agr. Biol. Chem. 39, 885-892. (67) Sakata, K., Sakurai, Α., and Tamura, S. (1975), Tetrahedron Letters, pp. 3191-3194. (68) Suzuki, S., and Okuma, K. (1958), J. Antibiot. 11, 84-86. (69) Suzuki, S., Nakamura, G . , Okuma, K., and Tomiyama, Y. (1958), J. Antibiot. 11, 81-83. (70) Okimoto, Y., and Misato, T. (1963), Ann. Phytopath. Soc. Japan 28, 209-215. (71) Okimoto, Y., and Misato, T. (1963), Ann. Phytopath. Soc. Japan 28, 250-257. (72) Ando, Κ., O i s h i , H., Hirano, S., Okutomi, T., Suzuki, K., Okazaki, H., Sawada, Μ., and Sagawa, T. (1971), J. Antibiot. 24, 347-532. (73) Hirano, S., Sagawa, T., Takahashi, H., Tanaka, Ν . , O i s h i , H., Ando, K., and Togashi, K. (1973), J. Econ. Entomol. 66, 349-351. (74) Ando, K., Murakami, Y., and Nawata, Y. (1971), J. Antibiot. 24, 418-422. (75) I i t a k a , Y., Sakamaki, T., and Nawata, Y. (1972), Chemistry Letters, pp. 1225-1230. (76) Ando, K., Sagawa, T., O i s h i , H., Suzuki, K., and Nawata, Y. (1974), Proc. 1st Intersectional Congress of IAMS (Science Council of Japan) 3, 630-640. (77) Sagawa, T., Hirano, S., Takahashi, H., Tanaka, N., O i s h i , H., Ando, K., and Togashi, K. (1972), J. Econ. Entomol. 65, 372-375. (78) Yamada, O., Kaise, Y., Futatsuya, F., Ishida, S., I t o , K., Yamamoto, H., and Munakata, K. (1972), Agr. Biol. Chem. 36, 2013-2015. (79) Nishimura, H., K a t a g i r i , K., Sato, K., Mayama, Μ., and Shimaoka, N. (1956), J. Antibiot. 9A, 60-62. (80) Sobin, Β. Α., and Tanner, F. W. Jr. (1954), J. Am. Chem. Soc. 76, 4053. (81) Yamada, O., Ishida, S., Futatsuya, F., I t o , K., Yamamoto, H., and Munakata, K. (1974), Agr. Biol. Chem. 38, 1235-1240. (82) Ishida, S., Yamada, O., Futatsuya, F., I t o , K., Yamamoto, H., and Munakata, K. (1974), Proc. 1st Intersectional Congress of IAMS (Science Council of Japan) 3, 641-650.


192

PESTICIDE CHEMISTRY IN THE 20TH CENTURY


(83) Aizawa, S., Nakamura, Y., Shirato, S., Taguchi, R., Yamaguchi, I., and Misato, T. (1969). J. Antibiot. 22, 457-462. (84) Yamaguchi, I., Taguchi, R., Huang, K. T., and Misato, T. (1969), J. Antibiot. 22, 463-466.


The Development of Agricultural Antibiotics - ACS Publications

Recommend Documents