Rapid Method for Extracting Constituents of Derris Roots R. H. HAGEMAN Federal Experiment Station, U.S . Department of Agriculture, Mayaguez, Puerto Rico
N WORK recently repoIted by Pagiii and Loustalot ( 2 ) i t was
I shown that the determination of total chloroform extractives of derris roots is one of the simplest and best criteria of toxicological value of these roots when correlated with biological assayed samples. Pagan and White ( 3 ) have also shown that total chloroform extractives can be used t o evaluate rotenoneproducing plants. The standard method for extracting derris root samples for total extractives and chemical analysis requires considerable time. The standard procedure for extracting derris root samples in this laboratory involves 3 hours of agitation in a mechanical shaker, a 16-hour standing period, and an additional hour of shaking. The samples are then removed from the shaker and filtered. The extraction xith the Waring Blendor requires but 5 minutes of agitation before the samples are filtered.
Table I. Total Chloroform Extractives Replicate
Standard method,
%
Series I
Blendor method,
%
Standard method,
%
Series I1 Blendor method,
14.50
Av. 15.76
*
0.29 15 82
i0 . 5 8
13 19
*
o.5a
70
*
The data presented in Table I show that the results obtained by the blender method of extraction are essentially the same as those obtained by the standard method. Rotenone determinations made with filtrates of both methods were almost identical. Samples extracted with the blender gave an average yield of 5.70y0 rotenone with a standard deviation of *0.05. The samples extracted by the standard procedure gave an average yield of 5.70 * 0.04%. Under prolonged use the chloroform has a tendency to dissolve the lubricant in the bearings of the Waring Blendor. This difficulty can be overcome by following the recommendat.ions of Hamilton and Gilbert (1). After using, the blender is cleaned first with solvent, and then with water. I t is then inverted and 2 or 3 drops of oil are placed in the shaft housing. The oil recommended is of the Pyroil B type. Prior to re-using for analyses after this treatment the blender is run for 10 minutes with fresh solvent. These results indicate that the use of the Waring Blendor in determining tot,al chloroform extractives and rotenone content of powdered derris roots is as effective as the standard procedure. I n addition to the same degree of accuracy the time of rxtraction is shortened from several hours to 5 minutes.
15.30 15.45
standard method and (2) the Waring Blendor; two series of six replicates were made by each method. After filtering to remove the marc a 10-ml. aliquot of the filtrates from both metho& of extraction was pipetted into an evaporating dish. The samples were then evaporated to dryness on a steam bath, dried in an oven a t 105" C. for 1 hour, and weighed to determine the total chloroform extractives.
0 29
A series of tests was made to compare extraction in the Waring Blendor with the st,andard method, using the weight of the total chloroform extractives as the criterion for complete extraction. The procedure in both methods was identical with the exception of the method of agitation.
LITERATURE CITED
(1) Hamilton, Joseph, and Gilbert, S. G., AKAL.CHEN.,19, 453-6 (1947). (2) Pag&n,C., and Loustalot, -4. J., J . Agr. Research (in press). (3) Pag&n, C., and White, D. G.. J . dssoc. Ofic. Agr. Chemists (in press).
Twenty-four 30-gram samples of derris root were taken from a uniform composite sample and each was mixed with 10 grams of Sorite ;i and 300 ml. of chlorofom and estracted by (1) the
KECI:IVEU.ipril 20, 1945.
Vacuum Column Head JOHN IM. DIEHL AND ISAAC HART Lewis Flight Propulsion Laboratory, National Adzisory C o m m i t t e e f o r Aeronautics, Cleveland, Ohio
N COSJUNCTION with a research program requiring the
often require a small trap which adds materially to the holdup and consequently to the difficulty of obtaining sharply divided fractions. Long-stemmed valves, operated by solenoids ( 5 , 8 ) , have been used to avoid this shortcoming and more recently the use of a small glass-enclosed bnll Ixnring valve is reported ( 1 ) .
I purification oi a large number of organic compounds by vacuum fractionation, it was desirable to develop a column head
that could be easily made and serviccd, yet provide for accurate regulation of reflux rate, accuratc vapor temperature measurements, and a very low holdup. AUteresperimenting with several designs, the head shown in Figure 1 \vas developed and put, into service. For accurate laboratory-size columna, the use of total condensation partial take-off heads rather than partial condensation total takeoff heads or dephlegmators has become a widespread practice within the past several years. hIany devices and methods have been used to avoid the difficulties inherent in the use of a stopcock or other throttling valve to control the reflux ratio. These difficulties have recently h e n enumerated by Berg ( 2 ) and Lloyd and Hornbacher (6). Still heads of either the intermittent 9) or reflux dividing (a, 3, 6, 7 ) type of take-off avoid iuo.st of these difficulties but
The head developed in this latmratorv incorporates a groundglass valve operated by a solenoid and can be made by a eompetent glass blomr in a few hours. The holdup is less than 0.1 ml. 4 single vent is provided a t the top of the hollow valve stem to eliminate slight pressure differentials in the distillate take-off tube (8) and thus assure smooth flow of the distillate. Above this vent, an iron core is attached to the valve stem and is enclosed in glass to avoid corrosion problems. The valve is lifted to a predetermined height by controlling the voltage input to a solenoid activated through an adjustable cycle timer. Construction problems are lessened by providing a ground-glass joint at the top of the head, which makes it possible to grind the valve easily and to remove the valve if cleaning becomes necessary. Three stopcocks in the head provide for changing sample bot-
(.$j
530
V O L U M E 21, NO.
4, A P R I L 1 9 4 9
531 i.les on a vacuum column. Tho stopcock in the distillate take-off line functions only to close the line against pressure during this operation. The vapor temporature is measured with a single- or multiplejunctian thermocouple in a well, looated directly in the path of the ascending vapors and close to the point of takeoff. The lower part of the head requires some insulation. The omission of a vacuum jacket greatly simplifies oonstruction; an enclosure of cellular pipe insulation is adequate for most purposes. The reflux ratio obtained with the head was considered to be equal to ratio of time off to time on of the timer. Because the valves seated almost perfeetly, with no leakage over long periods on all thc heads built, i t was felt, that this was a justifiable a s s u m p tion for the reflux ratios of 50 t.a 2 being used and the accuracy required. Heads of this type have been operated continuously on a 2 4 hour basis for over a year without leakage or other indications of wear or deterioration. LITERATURE C I T E D
(1) Bertleson,
J. D.. Conrad. A. L., and Far, P. S.,IND.ENG.CHEM..
ANAL.ED., 18,724 (1946).
(6) Lloyd, L. E., sndHornbaoher. II. G., Ibid., 19, 120 (194i). (7) Palkin, S., and Hall, S.A,. Ibid., 14,901 (1942).
(8) Podbielniak, W. J., Padbielniak Centrifugal Super-Coiltractor Co.. Circ. 22 (November 1942). (9) Snyder. J. C . , and Steubor. W..1x11.ENO.C H E ~ ANAL. ., En..16, 454 (1944).
Figure 1. Vacuum Column Head
R ~ C E I V ESatember D 1 1 , 194fi.
17. o-Aminophenol .
Good crystals of o-aminophenol can be prepared by sublimation. When sublimed macroscopically, the crystals are large enough and well enough formed to be used for single crystal x-ray measurements. When sublimed from one microscope slide to another they can be used for optical orystallogrslphy. Figure la, shows the characteristic preparation of o-aminophenal prepared by sublimation from one slide to another. Figure l b . shows a characteristic fusion pieparation of o-aminophenol. Figure 2
Figure 2. Orthographic Projection of Typioal Crystal of o-Aminophenol s h a m orthographic projection drilwings of a typical crystal of o-aminophenol. There was no evidence of polymorphism during crystallization from solutions or from the melt. b
Figure 1. o-Aminophenol a. Crystals obtained by sublimation from slide to cover glass (1. Fusion prepsretioo shoving oharactsristic ahrinkage rraeha
C R Y ~ TM~RPHOLOQY ~L (determined by W. C. McCrone). Crystal System. Orthorhombic. Farm and Habit. Tablets lying on the brachypinaooid I O l O l showing the hipyramid forms 1111). 11211, and (2121 and the mncropinacoid I1001
