Chemistry of Plant Gums and Mucilages and Some Related

Chemistry of Plant Gums and Mucilages and Some Related Polysaccharides (Smith, F.; Montgomery, R.) John W. Green. J. Chem. Educ. , 1960, 37 (11), p A7...
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Isotopic Tracers

G. E. Francis, St. Bartholomew's Hospital Medical College, London, W. Mulligun, Glasgow University Veterinary School, and A. W a n a l l , St. Bartholomew'sHospitalMedicalCollege,London. 2nd ed. Essential Books, Fair Lawn, New Jersey, 1960 (Oxford University 524 pp. Figs. and Press). xx tables. 14.5 X 22 cm. $8.40.

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This second edition is once sgsin s. publication of the course in Isotope Methodology given in the Medical College of St. Bartholomew's London. I t is organized in two parts, Part I heing titled "Theoretical Considerations" and Part 11, "Practical Course!' Part I contains two new chapters titled Interpretstion of Radioactivity Measurements and The Use of Isotopic Tracers in Investigations on the Kinetics of Biological Processes. Part I1 has also been considerably enlarged through the addition of seven new exercises covering these subjects: The Distribution of P-32 in Tissues following the Injection of P-3ZContsining Inorganic Phosphate into Mice, The Determination of Exchangeable Sodium in Rabbits, Using Na-24, Experiments on Thyroid, Experiments with Radioactive Iron, Labelling of Red Cells Simultaneoudy with P-32 and Cr-51, and Determination of the Intracellular Plasma. of Centrifuged Red Blood Cells. Exercise 1, The Use of Counting Apparatus for the Measurement of Radioactive Isotope8 has also been enlarged. In the preface to the second edition the authors state, "During the past four years tremendous advances have been made with regard to instrumentation . . ." and, "In writing this second edition we have been largely concerned with enlarging and hringing up to date the peetiom dealing with instrumentation and in expanding the section dealing with the practical side of tracer methodology . . . ." I t is the reviewer's opinion that the authors have not achieved their stated purpose. For example, in the chapter on Measurement of Stable Isotopes, fallowing a discussion of density methods for measuring deuterium, reference is made to the infrnred determination of HOD, and then the statement: "For the determination of all other stable isotopes a Mass Spectrometer is required." Apparently the authors are unaware of nuclenr magnetic resonance (NMR) methods, or that infrared measurements of deuterium-containing compounds other than HOD can be quite useful. Again, in their chapter on Measurement of Radioactivity, the reader is a p t to obtain a misleading impression of the very important and widely used ionieatian-chamber method for carbon-14 and tritium assay, for from the text one is left with the impremion that the most important application of the ionisation-chamber method is for "measuring dose raten for health protection purposes." In the chapter titled Synthesis or Preparation of Lahelled Compounds, the discussion of methods for deuterium labeling is limited to references to exchange reactions and to catalytic reductions with deuterium gas. There is no mention of the very useful and versatile reagent, lithium aluminum deuteride. In a discussion of the isotope effect, we find on page 16 the statement,

A750 / Journal of Chemical Education

"There is, however, no evidence that these 'isotope effects' are normally of great magnitude in the complex hioohemical systems of animal and plant organisms"-a very curious conclusion in view of the well-known work of several years standing a n the theory of the isotope effect by Bigeleisen, Melander, and Downes. In the hook there is much worthw.hile information which presumably is useful to the medical student who wishes to he exposed to some general principles of isotopic procedure as applied to physiology. For the research scientist, however, the material of value is readily available in several other texts. Further, the omission by the authors of much up-to-date information with respect to the isotope effect, instrumentation, and labeling procedures, materially detracts from its usefulness. "Isotopic Tracers" is therefore not recommended for the research chemist or hiochemist.

The reviewer is aware of the vast proh lem encountered by the authors, who did an admirable task of bringing order out of ohms. Yet he wishes they had been a. hit more decisive in regard to olaasificatian. In Chapter 2, entitled Classification of Gums and Mucilages, three main hhedings me given: acidic, neutral, and a hypothetical basic group (for future synthetic gums). Yet throughout moet of the hook (with the exception of Tables 28 to 31) the palysaocharides are classified according to occurrence. This book is a very specialized manograph for the research worker in the carbohydrate field. About a third of it is concerned with the structure of polysaccharides in general; the rest is highly descriptive, de~ignedfor the specialist.

JOHN W. GREEN Institute of Papel Chmnislw Appleton, Wisconsin

CLAIRJ. COLLINB

Oak Ridge National Laboratory Oak Ridge, Tennessee

Chemistry of Plant Gums a n d Mucilmges and Some Related Polyrarcharides F. Smith, University of Minnesota, St. Paul, and R. Montgorner~~,State University of Iowa, Iowa City. (ACS Monograph No. 141.) Reinhold Puhlishing Corp., New York, 1959. x 627 pp. Figs. and tables. I6 X 23.5 cm. $18.

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This hook is specialized, dealing with s large group of waterwduhle or dispersible plant polysacchwides. The authors have done a commendable job of uniting in one hook a vast amount (2700 references) of information concerning the chemistry of these materisls. Approximately 100 polysaccharides are discussed, according to their occurrence and also according to their chemical structure. They are listed as gum exudates and as constituents of seeds, roots, and seaweeds. The reader will be aware of some of these, as gum arahic or gum tragtgacanth. The care of the book (six chapters) is devoted to the determination of molecular weight, to the identification of the several sugar units, and to the elucidation of structure by methylation techniques and periodate oxidation. These chapters, while directed specifically a t certain given polysaccharides, can be applied to polysaccharide chemistry in general. At the end of the hook is given alist of the various methylated sugar units and their physical properties, a vsluahle aid to the laboratory worker. This list complements Chapter 10 (The Identification of the Cleavage Products of Methylated Gums and Mucilages). A series of five chapters deals with the structure of the several classes of gums, the classification being according to occurrence. An earlier chapter deals with the detection and identification of the various types. These chapters are descriptive and contain a vast amount of empirical detail.

Instrumental Methods of Chemical Analysis Galen W. Ewing, New Mexico Highlands University, Lss Vegss, New Mexico. 2nd ed. McGraw-Hill Book Ca., Inc., New York, 1960. viii 454 pp. Figs. and tahles. 16 X 23.5 om. $8.90.

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The second edition of this text retain8 most of the desirrthle features of the earlier work (reviewed in THIS ~ O U I I N A L , 32, 546 (1955)), and the author continues to present the theory and application of selected modern analytical techniques a t a level that can he comprehended by advanced undergraduate and firsbyear graduate students. In order to bring his treatment up to date Profe~sorEaing has rearranged same of the material, deleted certain discussions and expanded others, and added a few new topics. In the new sequence, optical methods are presented first. This unit of six chapters (148 pages) is pteceded by an introductory chaptor comprised largely of sections from sesttewd chapters of the earlier edition; to this have heen added some useful energy-level diiglsms. Chapter 3, The Absorption of Radiation: Ultraviolet and Visible, contains improved and expanded sections on slective a b sorption, structure determination, and precision photometry: and the discussion of the identification of a mmplex is a welcome addition. Chapter 1, The Absorption of Radiation: Infrared, has been strengthened by the inclusion of frequency assignment charts and information concerning the properties of infmred transmitting materials. The reviewer regrets, however, that drastic deletions were made in revising Chapter 8, Refractivity and Disoersion i n o r onlv 5 uapesI. Certain found in many other refermeen. A second unit of four chapters (87 pages) on electroehemiesl methods is also preceded by s new introductory c h a p ter. In this introduction the reviewer (Conlinued on page A76e)