Opinion: The accustomed inconsistency in biochemical ecology – Enhanced knowledge of the evolution and function of natural products frequently implies teleological misinterpretations

Secondary plant products are the basis for complex interactions between plants and their environment. By protecting plants against pathogens and herbivores or by attracting potential pollinators, they accomplish various and distinct ecological functions. The enormous diversity of these natural compounds is the result of evolutionary processes that have been driven by the selection of corresponding advantageous properties. Unfortunately, when discussing this con-text, we frequently formulate statements such as “Plants have ac-quired the ability to synthesize secondary plant products in order to...” without realizing that such assertions contradict the Darwinian principles of evolution and thus represent the Lamarckian view of a teleological evolution. The primary reason for these unconscious misapprehensions seems to be the ambiguous usage of the term “biological function”, whose denotation frequently includes an inten-tion or a special purpose. In this treatise, the related associations and conclusions are outlined and depicted

Modern Applied Botany: Changes in the perception of applied botanists to themselves and others during the last century.

Subsequent to a short chronicle of the history of applied research in plant biology in Germany, the relevance of modern Applied Botany is illustrated by three relevant post-harvest processes. The metabolic reactions that play a key role in the determination of quality of the related plant-derived commodities from each are presented. Increased understanding of the processes involved in these processes has facilitated improvement of product quality in the resulting products. In each instance, it has been necessary to regard plant metabolism comprehensively and not to focus on a single physiological process. Moreover, the various interactions with the environment have to be considered. These illustrations demonstrate that transfer and application of basic plant knowledge into product-related research can provide significant information that is valuable for improvement of plant-derived products. In some instances, these correlations can even account for traditional and well-established processes, as illustrated for the malting process.  However, interdisciplinary work and intensive cooperation with growers and producers must be an integral part of developing feasible and economically acceptable solutions that can be transferred into practice. Ultimately, the major challenge in Applied Botany today is the implementation of new concepts and ideas into product-related research.  In consequence, modern Applied Botany acts as a mediator between basic plant science and industrial, product-related research

Case study: The difficulty of correct reference values when evaluating the effects of drought stress: a case study with <i>Thymus vulgaris</i>

Medicinal and spice plants grown under semi-arid conditions frequently contain higher concentrations of relevant secondary metabolites than plants cultivated in moderate regions. It is well established that this phenomenon is due to the impact of drought stress. However, in principle, the increase in natural product concentration could be caused by two quite different effects. Firstly, it could be caused simply by a change of the reference values: typical stress-related reduced growth frequently results in a lower biomass of the stressed plants. In consequence − provided that the rate of natural product biosynthesis remains constant − this results in an enhanced concentration in the stressed plants. Secondly, there is a genuine stress-related increase in the rate of biosynthesis of secondary metabolites. In the first case, the total amount of secondary metabolites remains constant, while in the second case, it increases. Accordingly, a thorough differentiation requires a reliable quantification and comparison of the relevant factors. This especially accounts for the total biomass, which generally is far less in drought stressed plants than in the well-watered ones. Consequently, in all studies, where data on the total biomass are lacking, it is not feasible to evaluate reliably the total amounts of secondary metabolites only on the bases of the concentrations determined. Unfortunately, in most of the corresponding literature published so far, these data are missing, and thus, it is not possible to decide whether the drought stress-related increase of secondary metabolites is due to a genuine increase in biosynthesis or whether it is just due to a change of the relevant reference values, i.e., the total biomass. In this study, the relationships of these factors in well-watered and drought-stressed thyme plants are examined and discussed

Influence of feed supplementation with Tropaeolum majus L. on growth performance and urine isothiocyanate concentration of piglets

Die Kapuzinerkresse (Tropaeolum majus L.) ist eine Heilpflanze, die eine stark antimikrobielle Wirkung zeigt und im Humanbereich gegen Blasenentzündungen bereits wirkungsvoll eingesetzt wird. Die antimikrobielle Wirkung wird dabei durch das Abbauprodukt des Inhaltsstoffes Glucotropaeolin, durch das Benzylisothiocyanat, erzielt. In einem fünfwöchigen Versuch mit Ferkeln wurde getestet, inwieweit sich ein Futterzusatz von glucotropaeolin-haltigen Kressesamen auf die Futteraufnahme und die Gewichtszunahme von Ferkeln auswirkte. Tropaeolum majus wurde in drei unterschiedlichen Mengen zugesetzt und eine Kontrollgruppe ohne Futterzusatz wurde untersucht, wobei eine maximale Konzentration von 1&nbsp;g/kg Futter zugesetzt wurde, was einer Menge von 48,7&nbsp;mg Glucotropaeolin/kg entsprach. Aus dieser Glucotropaeolingabe resultierte eine Isothiocyanatkonzentration im Urin von maximal 2,4&nbsp;mg/L, welche hoch genug ist, um ein breites Spektrum an Bakterien zu kontrollieren. Im Durchschnitt wurden 3,1 – 7,3% des verabreichten Glucotropaeolins in Form von bioaktivem Benzylisothiocyanat mit dem Urin wieder ausgeschieden. Kapuzinerkresse hatte als Futterzusatz keinen Einfluss auf das Wachstum und die Futteraufnahme der Ferkel.Tropaeolum majus L. is a herb with antimicrobial activity in humans, caused by the degradation product benzyl-isothiocyanate derived from enzymatic cleavage of glucotropaeolin. Piglets were fed diets with a graded supplementation of Tropaeolum majus for five weeks. Tropaeolum majus was supplemented at an upper dosage level of 1&nbsp;g/kg with the feed, equaling 48.7&nbsp;mg/kg glucotropaeolin, which resulted in a benzyl-isothiocyanate concentration in the urine of up to 2.4&nbsp;mg/L, which is high enough to control a broad range of bacteria. On average 3.1 – 7.3% of the glucotropaeolin taken up by the animals was excreted as bioactive benzyl-isothiocyanate. Supplementation of the feed with Tropaeolum majus had no effect on growth performance of piglets

Protein content and glucosinolates from Moringa oleifera Lam. – New insights into an auspicious commodity

Moringa&nbsp; oleifera&nbsp; is&nbsp; considered&nbsp; to&nbsp; be&nbsp; one&nbsp; of&nbsp; the&nbsp; most&nbsp; valuable&nbsp; and&nbsp; beneficial crop tree species. The great nutritiousness is assigned to its&nbsp; high&nbsp; leaf&nbsp; protein&nbsp; content,&nbsp; and&nbsp; its&nbsp; health-promoting&nbsp; effect&nbsp; to&nbsp; the&nbsp; anti-carcinogenic&nbsp; properties&nbsp; of&nbsp; its&nbsp; genuine&nbsp; glucosinolates&nbsp; and&nbsp; their&nbsp; degradation products.From&nbsp; a&nbsp; plant&nbsp; physiological&nbsp; perception&nbsp; protein&nbsp; contents&nbsp; of&nbsp; 30%&nbsp; seem to be quite high. Accordingly, a reconsideration of these findings became necessary. The related inquiry unveils that also in the leaves&nbsp; of&nbsp; many&nbsp; other&nbsp; plant&nbsp; species&nbsp; such&nbsp; high&nbsp; protein&nbsp; contents&nbsp; are&nbsp; reported, provided that they are quantified by Kjeldahl nitrogen determinations. But, it is rather likely that the nitrogen accounting for the putative high protein contents is due to insoluble cell wall bound hydroxyproline-rich glycoproteins. Due to their extreme insolubility, these&nbsp; compounds&nbsp; cannot&nbsp; be&nbsp; digested&nbsp; easily,&nbsp; and &nbsp;thus,&nbsp; they&nbsp; do&nbsp; not&nbsp; contribute to the nutritiousness of M. oleifera leaves.In contrast to classical glucosinolates, those occurring in M. oleifera are characterized by an attachment of a rhamnose to the aglycone. In consequence, the products generated during the myrosinase-cata-lysed hydrolysis correspond to non-volatile rhamnosides of isothiocyanates. Since over time, olfactorily active substances emerge, the rhamnose moiety has to be cleaved off, putatively by a corresponding rhamnosidase