Book reviews seminar, including: standard assays for ligninolytic activity; assessment of the rates and true roles of tignin polymer metabolism by bacteria and imperfect fungi; elucidation of the pathway(s) for biodegradation of the lignin polymer, and of the genetic and regulatory aspects of the ligninolytic system(s); determination of whether the lignino-
lytic system(s) are cell-bound or freely diffusable; and the continuous evaluation of potential applications. Numerous possibilities for utilizing ligninolytic systems were recognized and discussed, but applications probably await a more thorough understanding of the microbiology, biochemistry, and particularly the
Advances in Biochemical Engineering, Vol 8
suitability of a tower-type fermenter for the growth of Candida boidinii. A very ambitious programme of work is described which includes the measurement of gas-bubble size distributions and oxygen concentration profiles as well as cell growth. There is a useful but rather quahtative introductory section on fundamental aspects of surface phenomena and their influences on foaming, bubble size and mass transfer. However, although many references are cited throughout the chapter, the work that is presented is not critically compared with any similar published results. The concluding chapter presents results of experiments carried out by the author to measure absorption coefficients in a gas-liquid contactor. Measurement techniques included sulphite and hydrazine oxidation and the operation of the fermenter as a constant pressure respirometer. No attempt is made to compare the results obtained from each method, nor to justify any of the work by comparison with other published data in this field. The use of the word 'sorption' in this paper when referring to gas-liquid mass transfer processes must be discouraged because that word already has a well defined meaning in the field of adsorption phenomena. The overall impression is that the volume contains much useful biochemical engineering material and is worthy of a place on the shelf with its predecessors. However, it is disappointing that almost half of the text, although representing considerable careful work by several authors, is not presented in the style of a critical review.
Editors: 7". K. Ghose, A. Fiechter and N. Blakebrough Springer-Verlag, Berl i n Heidelberg-New York, 1978, 151 pp., DM 58.00, US $29.00
'Advances in Biochemical Engineering' attempts, in the tradition of other 'Advances' series, to present critical state-of-the-art reviews of chemical engineering aspects of biotechnology. Volume 8 of this series is a slim edition containing only three articles but each one deals relevantly with biochemical engineering problems. However, it is evident that two of the three articles are reporting original work and do not contain the broad critique anticipated by many readers. Although the viscous nature of many fermentation broths has caused difficulties in process operations for many years, it is only in relatively recent times that economic aspects have driven engineers to examine the problem. The first chapter of this volume attempts to survey the state of knowledge in this field and to point the way, through further research, to improvements in design and operating procedures. A most useful summary of the basic principles of rheology is presented which includes instruction in the methods of measurement. From this good start the article becomes less orderly as the author attempts to discuss the interaction of viscous properties with such topics as mixing and oxygen transfer. This is a useful contribution which highlights the large amount of ignorance which still exists in this complex area of biotechnology. The second article is a report of experiments carried out to assess the
D. E. Brown
chemistry and genetics of the processes. Much research remains to be done, but progress is expected to be rapid. The seminar proceedings are to be published by CRC Press, Inc., and should be available early in 1979.
T. K. Kirk
Dictionary of Microbiology Paul Singleton and Diane Sainsbury John Wiley & Sons, Chichester, 1978, 481 pp., £17.50 In the usual sense, dictionaries are not read as are other books, but a great deal of this book will be read, because in addition to the short definitions many of the entries are interesting concise reviews, some occupying as much as a whole page. The extensive system of cross referencing is good, so that the reader is easily led to seek further than the original entry, usually to advantage. The publishers claim, not likely to be disputed, is that there are over one thousand microbial taxa. The authors are to be congratulated on the excellent detailed description of these since, as well as the usual criteria, there is a great deal of information on other characteristics of a group. In a number of entries the information is sufficient to differentiate to species level. Where the reference is to a technique, this frequently gives sufficient detailed information on, for example the method for a test, a staining procedure, constituents and quantities for a culture medium, so that reference to other sources is unnecessary. An appendix contains numerous metabolic pathways, and each is clearly described using two colours. This dictionary is comprehensive, clearly written and well produced. The authors have succeeded in their attempt to produce a compact source of readily available and up-to-date information. The book is strongly bound in hard covers, which is necessary because the dictionary will be used frequently. E. T. J. Chelton
Enzyme Microb. Technol., 1979, Vol. 1, April 149