Alkaloids of the leaves of Voacanga grandifolia

Besides vobtusine and vobtusine-lactone, deoxyvobtusine was isolated from the leaves of Voacanga grandifolia (Miq. Rolfe. Spectral and chemical evi     

Role of Melanin in Release of Extracellular Enzymes and Selection of Aggressive Isolates of Bipolaris sorokiniana in Barley

Eighteen barley isolates of Bipolaris sorokiniana belonging to wild and clonal type of black, mixed and white subpopulations were quantitatively assayed for their melanin content and aggressiveness with respect to production of some of the extracellular enzymes such as cellulase, pectinase, amylase and protease. Cellulase and pectinase constituted major portion of the enzymes recovered from the black, mixed and white isolates. Enzyme production and aggressiveness were relatively higher in melanin devoid or low melanin isolates. The melanin deficient isolates were also differentiated from black and mixed isolates on the basis of variation in internal transcribed spacer region of the ribosomal DNA. Higher enzyme productions positively correlated with area under disease progress curve (AUDPC) and lesion development. Melanin content was negatively correlated with extracellular enzymes and aggressiveness of the isolates. Based on melanin content, lesion size, AUDPC and extracellular enzymes, the isolates were grouped in two major clusters (I and II) with further division of cluster II into two sub-clusters (II-A and II-B). The results appears to indicate a possible role of melanin in release of extracellular enzymes and hence in evolution and selection of aggressive isolates of B. sorokiniana in barley.     

Microbial reduction of ethyl acetoacetate using Sclerotium rolfsii

Summary A method for the quantitative enantioselective bioreduction of ethyl acetoacetate [1] to optically pure (+)-S-ethyl-3 hydroxybutyrate [II] usingSclerotium rolfsii mycelium is described. In a synthetic medium 1 g mycelium (dry weight) could convert 1 g of I to II within 2–3 days of fermentation (pH 5.8, 30°C). This is the first report demonstrating use ofS. rolfsii biomass for asymmetric reduction to get chiral building blocks.     

Metabolism of larger high density lipoproteins accumulating in some families of baboons fed a high cholesterol and high saturated fat diet

Progeny of certain baboon sires accumulate lipoproteins in high density lipoprotein-1 (HDL1) when challenged with a high cholesterol, high saturated fat diet. These studies were conducted to determine the apoprotein composition and metabolic fate of HDL1 in the plasma. HDL1 particles containing apoA-I with and without apoE were detected. The majority of particles, however, contained apoA-I without any detectable apoE. To determine the metabolic fate of HDL1 in plasma, HDL1 labeled with iodinated apoA-I from animals with high levels of HDL1 and iodinated apoA-I-labeled autologous HDL were coinjected into both high and low HDL1 animals. The data for the decay of radioactivity in HDL1 and HDL were analyzed by multicompartment modelling. The radioactivity from HDL1 was cleared from the plasma either via direct removal (9.1 +/- 4.7% in low and 21.7 +/- 8.3% in high HDL1 animals) or via its conversion to HDL. A large proportion of radioactivity from HDL1 was rapidly transferred to HDL directly or metabolized via an intermediate compartment. Most of the radioactivity from apoE-poor HDL1, however, was transferred to HDL. Both high and low HDL1 animals catabolized HDL1 and HDL similarly. Low HDL1 animals transferred HDL1 radioactivity to HDL much faster. No detectable radioactivity from HDL was transferred to HDL1. Thus, HDL1 that accumulates in high HDL1 animals is mainly a precursor for HDL. Our hypothesis is that this accumulation of HDL1 is due to the slower cholesteryl ester transfer from HDL to lower density lipoproteins, thus affecting reverse cholesterol transport in high HDL1 baboons.     

Litter and soil biodiversity jointly drive ecosystem functions

The decomposition of litter and the supply of nutrients into and from the soil are two fundamental processes through which the above- and belowground world interact. Microbial biodiversity, and especially that of decomposers, plays a key role in these processes by helping litter decomposition. Yet the relative contribution of litter diversity and soil biodiversity in supporting multiple ecosystem services remains virtually unknown. Here we conducted a mesocosm experiment where leaf litter and soil biodiversity were manipulated to investigate their influence on plant productivity, litter decomposition, soil respiration, and enzymatic activity in the littersphere. We showed that both leaf litter diversity and soil microbial diversity (richness and community composition) independently contributed to explain multiple ecosystem functions. Fungal saprobes community composition was especially important for supporting ecosystem multifunctionality (EMF), plant production, litter decomposition, and activity of soil phosphatase when compared with bacteria or other fungal functional groups and litter species richness. Moreover, leaf litter diversity and soil microbial diversity exerted previously undescribed and significantly interactive effects on EMF and multiple individual ecosystem functions, such as litter decomposition and plant production. Together, our work provides experimental evidence supporting the independent and interactive roles of litter and belowground soil biodiversity to maintain ecosystem functions and multiple services.     

Analysis of phase stability,elastic, electronic,thermal, and optical properties of Sc1-xYxN via ab initio methods

Journal of Molecular Modeling - The recent advances in the application of machine learning to drug discovery have made it a ‘hot topic’ for research, with hundreds of academic groups...     

Effect of continuous light and darkness on the testicular histology of toad (Bufo melanostictus)

Continuous darkness decreases spermatogenesis as well as Leydig cell function whereas continuous illumination suppresses spermatogenesis along with increased Leydig cell activity.