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Book Review Biomineralization Chemical and Biochemical Perspectives. Edited by S. Mann J. Webb and R. J. P

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cellulose, up to its complete carbonization, are discussed in
the light of spectroscopic and chromatographic evidence.
However, the number of different variables involved in the
pyrolysis process is so great that it is probably not realistic to
expect a clear relationship between chemical changes of the
fiber matrix and the structural and mechanical properties to
emerge here.
Chapter 5 is the longest and the most important as regards
detailed information content; it deals with the preparation of
doped C-fiber materials, with special attention to the effects
of different additives on the pyrolysis process. Although the
effects occurring during the different stages of the process
are many and varied, the authors succeed very well in deriving a systematic relationship between the chemical properties
of the additives and their effects on the pyrolysis process.
Chapter 6 is entitled “Surface Modification of C-Fibers”.
The main emphasis is on the introduction of ionic groups in
relation to ion-exchange applications, and on chemical and
thermal methods for increasing the adsorptivity of C-fibers.
Compared with this, the surface modification of C-fibers
to improve their adhesion properties in polymer and metal
fiber-reinforced composites is treated rather too briefly. Also
in the applications described in Chapter 7 the authors limit
their account mainly to low-modulus fibers and their typical
applications in the areas of adsorption, catalysis and medical
science. Uses of C-fibers in composite materials are treated
briefly, and for applications of high-modulus fibers the reader is referred to already existing reviews.
Although this monograph does not cover all aspects of the
chemical modification of C-fibers, it is a useful survey within
this specialized field. The qualities of the book that impress
are its high information content and the many literature
references, which in some parts raise it to the standard of a
handbook. It can be strongly recommended for the readership intended by the authors.
Worfgang Meyer [NB 1085 IE]
Max-Planck-Institut fur Polymerforschung,
Mainz (FRG)
Mycotoxins. Chemical, Biological and Environmental Aspects. (Series: Bioactive Molecules, Vol. 9). By V. Betina.
Elsevier, Amsterdam
1989. 438 pp., hardcover,
HFI 295.00.--ISBN 0-444-98885-8
The book gives an overview of the most important mycotoxins, their occurrence, their structures and physicochemicat properties, the fungi that produce them, their biosyntheses and their biological activities.
Chapter 1 covers very briefly, but also in a way understandable even to non-microbiologists, some aspects of the
taxonomy and chemotaxonomy of mycotoxin-producing
fungi. Mycotoxins and their producers are summarized very
clearly in four tables, with indications of the chapters in
which they are treated more thoroughly.
Chapter 2 covers general aspects of secondary metabolites, which include mycotoxins. The most important topics
and theories are introduced and discussed.
Chapter 3 summarizes the most important biological effects of mycotoxins. In addition to the toxic effects on man
and mammals, their effects on insects, plants and other microorganisms are discussed. The relevance of biological
screening is also discussed. Chapter 4, on modes of action,
describes many different sites of action and metabolic pathways that are affected by mycotoxins. Unfortunately there is
not much critical evaluation of published results. A distinc214
0 VCH Verlagsgesellschafl mbH, W-6940 Weinheim, 199i
tion between primary and secondary effects would have been
helpful to the non-specialist. Chapter 6 briefly describes
some ecological aspects of toxins and the organisms that
produce them. With regard to methods of detection, biological tests are described in most detail.
In the second half of the book, covering 12 chapters, the
most important mycotoxins are described, and arranged by
chemical structure or biological action. The aflatoxins,
sterigmatocystins and versicolorins, the ochratoxins and related compounds, citrinin, the tricothecenes, patulin and
other small lactones (penicillic acid, mycophenolic acid,
butenolide, citreoviridin), zearalenone, the cytochalasans,
rubratoxins, anthraquinones, tremorgenic mycotoxins (including penitrems and paspaline) and epipolythiopiperazine3,6-diones such as gliotoxins and chaetocins, are all comprehensively described.
The chapter “Miscellaneous Toxins” deals very briefly
with PR toxin, secalonic acid D, viridicatum toxin, cyclochlorotine, cyclopiazonic acid, moniliformin and fusarin C.
For each mycotoxin, information on the organism that produces it, its occurrence, the biosynthesis of the toxin, its
isolation and physicochemical characterization, its structure, biological activity, mode of action and ecological aspects is set out very clearly.
The book has several merits; it is easy to follow, well-organized, and contains essential information for all the toxins
listed, covering the literature up to 1988 inclusive. The mycotoxin producing organisms are listed separately in the index.
It is almost unavoidable for a book of this size to also contain some flaws. The formula of one of the tautomeric forms
of mycophenolic acid (p. 244) is incorrect. Beside the formula for moniliformin there is an extra unrelated group.
Overall, this book serves as an up-to-date compilation of
the most important mycotoxins. It can be recommended as
a reference work, as an introduction to the subject, or as an
accompaniment to lectures. Unfortunately the variety of biological effects are often only listed but not evaluated, which
reduces the value of the book for the non-biological reader.
Timm Anke [NB 1094 IE]
Lehrbereich Biotechnologie
der Universitat Kaiserslautern (FRG)
Biomineralization, Chemical and Biochemical Perspectives.
Edited by S. Mann, J. Webb and R. J. P. Williams. VCH
Verlagsgesellschaft, Weinheim/VCH Publishers, New
York 1989. xiv, 541 pp., hardcover, DM 274.00. ISBN 3-527-26750-6/0-89573-672-1
Reports on international conferences about aspects of
biomineralization appear at nearly regular intervals of four
to five years. A particularly important contribution on this
topic was that of the 1981 Dahlem conferences (Lve Science
Research Report 23). Up to then biomineralization had been
understood to be a process involving the formation of insoluble calcium compounds. In addition biomineralization had
come to be regarded as a biological phenomenon that also
includes pathological aspects such as the formation of stones
in the body, and demineralization processes (osteoporosis,
caries). Since 1983, however, the term biomineralization has
started to undergo a change of meaning to include the area
of “biological metal accumulation”, and appears to be becoming a part of “bioinorganic chemistry”. Thus the original meanings of the terms are gradually becoming blurred.
The bood reviewed here is well produced and appeais at
an opportune time, especially in view of the fact that, in
addition to the emergence of the aspects mentioned above,
0570-0833~91i0202-02i4$3.50+.25/0
Angew. Chem. h i . Ed. Engl. 30 (1991) No. 2
new developments in techniques now necessitate an updated
treatment of the subject. The material is divided into 15
chapters which are written in the style of review papers. The
topics covered are as follows: the functional forms of
biominerals; crystallographic strategies of biomineralization; the carbonate calcification of algae, matrix-crystal interactions in CaCO, biomineralization; stereochemical and
structural relationships between macromolecules and crystals in biomineralization; in vitro studies of calcium phosphate crystallization; biochemical studies of teeth mineralization in vertebrates, chemical studies of biogenic silicates;
function and structure of ferritin and hemosiderin, biomineralization of iron in the teeth of molluscs; mineralization of
magnetite in unicellular organisms; structural and analytical
studies of metal ion-containing granules; the use of proton
beam analysis in studies of mixed biominerals; the significance of studies on biomineralizates for materials technology.
The contents are, without exception, good and the treatment of the subject matter is impeccable. For the specialist
the book offers a rich source of ideas and suggestions. However, only three of the articles are concerned with matrixcrystal interactions, which is the central topic of biomineralization. Moreover, two articles on this subject put forward
controversial views, giving the impression that the role of the
organic matrix is questionable, or at least unimportant (see
also the preface). The reader is left alone with this problem,
without being given a clear answer. Some time ago S . Munn,
in his article “Biomineralisation” (Chem. Unserer Zeit 20
(1986) 69), gave a much better, unambiguous and impressive
statement of his position on this question. There he clearly
and unequivocally explained the difference between geological minerals and biomineralizates. The fundamentals of
techniques and theory are certainly a part of this question.
Here an unusually large amount of space is devoted to these
aspects and to crystal structure studies. Moreover, of the
total of about 500 pages of text, almost 200 are devoted
solely to iron, resulting in a serious imbalance. Lengthy discussions about ferritin structures have very little to do with
biomineralization. Alongside these chapters the more biologically orientated articles give the impression of having
been grafted on. Only one page is given to pathological
biomineralization processes. However, apart from these few
inconsistencies. the book opens up some useful chemical and
biochemical perspectives.
Gottfried Krumpitz [NB 1102 IE]
Institut fur Anatomie, Physiologie und Hygiene
der Haustiere
der Universitat Bonn (FRG)
Reizvolle Molekiile der Organischen Chemie. (Series: Teubner Studienbucher Chemie). By F: Vogtle. Teubner, Stuttgart 1989. 402 pp., paperback, DM 39.80. -ISBN 3-51903503-0
Each volume in the series “Teubner Studienbucher
Chemie” deals with fundamental and more advanced aspects
of a particular field of chemistry. The books do not aim at
the breadth of coverage of a textbook, nor at the depth of
treatment of a comprehensive monograph; instead they are
intended only to give the student of chemistry an introduction
to specialized topics that are of current interest, and which
are therefore undergoing rapid development.
In the volume “Reizvolle Molecule der Organischen
Chemie” published in 1989 (and also in the following volume
Angew. Chem. In[. Ed. Engl. 30 f 19911 No. 2
8 VCH
“Supramolekulare Chemie - Eine Einfiihrung”,’*] which appeared almost simultaneously), Fritz Vogtle presents a survey of “attractive molecules” relevant to his field of study.
His starting point is a wish to open up to the reader, in a way
that is both instructive and entertaining, the great variety of
organic chemistry, by taking him or her on a journey of
discovery through the field of unusual molecules and all that
relates to them (their history, synthesis, chemical and spectroscopic properties, and applications). In the resulting thoroughly readable organic chemistry book, the appeal of the
“attractive molecules” referred to in the title is revealed not
least through the many lavish stereoscopic illustrations
which provide three-dimensional views; Vogtle’s artwork
studio has already set a high standard of quality with illustrations such as these in numerous publications. They are a
delight to the eye! Or, as the author himself puts it on page
23: not least of the aimes was that merely looking at the
structures shown here should bring joy to the heart of every
chemist!
Among the most notable of the “attractive molecules”
that Vogtle has in mind in the title of the book are hydrocarbons that are to some degree exotic. Accordingly, the introduction (19 pp.) is followed by detailed excursions into the
chemistry of interesting aliphatic hydrocarbons (Chapter 2,
56 pp.), arenes (Chapter 3, 115 pp.), and “araliphatics”
(Chapter 4, 65 pp.). It is evident that deciding what to include or leave out must have been a painful choice. Some of
the interesting molecules that were filtered out are the following: tetra-tert-butyltetrahedrane, cubane, dodecahedrane, adamantane, pagodane, and [l . l .l]propellane (Chapter 2); the triphenylcyclopropenyl cation, azulene,
biphenylene, circulene, and [7jhelicene (Chapter 3); triptycene, iptycene, 1$-methanonaphthalene, [2.2.2jcyclophane,
and superphane (Chapter 4). As one can see from the restrictions placed on the material included, no attempt has been
made in Vogtle’s book to cover the entire field of exotic
hydrocarbons. Instead, rigorously limiting the coverage to
just a ,few candidates has made enough space available to
allow a satisfying breadth and depth in the treatment of the
material.
The meticulous care that Vogtle has brought to the task of
doing justice to the title of the book is evident from the
lengths of the bibliographies to the chapters, which amount
to a total of 31 pages! In a literature study of such a high
standard as this, it is not surprising to find that only a few
years ago it would not have been possible to write this particular book, despite the fact that the topic of exotic hydrocarbons is far from new. Among the recent reactions included
are the synthesis of cubene (October 3988), Prinzhuch’s second-generation syntheses of dodecahedrane (March 1989)
and the anionic polymerization of [I. 1.1jpropellane (May
1989).
Whether one’s interest lies mainly in deeper subjects such
as a comparison of azulene syntheses, in relationships between structure and color in azulenes, in the regioselectivity
of electrophilic substitutions of biphenylenes, of 1,smethanonaphthalene or of cyclophanes, whether one wishes
to become enmeshed in the three-dimensional structural formulas of the helicenes, heterohelicenes or helicenophanes, or
goes in search of curiosities such as information about
adamantane chemistry being carried out on u tonnage scale in
Japan with the aim of treating Parkinson’s disease, or about
evidence for the presence of the cyclopropenylium ion in
Halley’s comet, Vogtle’s book offers something for everyone
who enjoys browsing among topics in organic chemistry that
[“I
Review: Angew. Chem. 102 (1990) 112.
Verlagsgesellschaft mbH, W-6940 Weinheim, 1991
0570-0833191jO202-0215S 3.50+ .25/0
21 5
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