Identification of fatty acids in submerged cultures of Claviceps species

Abstract Fatty acids were identified in the submerged mycelium of Claviceps purpurea, Claviceps paspali, Claviceps fusiformis and Claviceps sp. SD-58 by gas chromatography-mass spectrometry (GC-MS) and used for a chemotaxonomical study. A close relatedness was found between Claviceps sp. SD-58 and C. fusiformis . The composition of fatty acids in high-production mutants differed substantially from that of the parent strains. Fatty acid analysis is thus probably only applicable in the taxonomy of non-mutated isolates of Claviceps cultured under standard conditions.     

3种沉水植物水浸提液中有机酸成分分析

随着工业化的不断发展,湖泊富营养化程度不断加剧[1].水生植物是水环境中重要的初级生产者,能消耗水体中大量的氮、磷等物质[2],并能吸收富集污染物质[3].     

Biosynthesis of amino acids from hydrocarbons

Optimum conditions for the growth ofPseudomonas arvilla, a hydrocarbon utiliser, have been studied. The microorganism produced economic cell yield at pH 5.7 and 4% kerosene concentration. C₁₀-C₁₆ hydrocarbons were utilised by the strain. The growth was maximum on n-decane. Supplementation of the hydrocarbon medium with 0.5% glucose stimulated the growth. Glutamic acid 16.0 mg; leucine 9.0 mg; valine 10.0 mg; methionine 2.5 mg; arginine 2.5 mg; histidine 1.0 mg were present in 100 ml of the broth. Cell protein contained leucine 13.69%, isoleucine 4.9%, histidine 4.37%, tryptophan 2.33%, methionine 1.8% and arginine 2.70%.     

Optimization of exopolysaccharide production from Armillaria mellea in submerged cultures

Aims: To study the optimization of submerged culture conditions for exopolysaccharide (EPS) production by Armillaria mellea in shake‐flask cultures and also to evaluate the performance of an optimized culture medium in a 5‐l stirred tank fermenter. Methods and Results: Shake flask cultures for EPS optimal nutritional production contained having the following composition (in g l^?1): glucose 40, yeast extract 3, KH₂PO₄ 4 and MgSO₄ 2 at an optimal temperature of 22°C and an initial of pH 4·0. The optimal culture medium was then cultivated in a 5‐l stirred tank fermenter at 1 vvm (volume of aeration per volume of bioreactor per min) aeration rate, 150 rev min^?1 agitation speed, controlled pH 4·0 and 22°C. In the optimal culture medium, the maximum EPS production in a 5‐l stirred tank fermenter was 588 mg l^?1, c. twice as great as that in the basal medium. The maximum productivity for EPS (Q_p) and product yield (Y_P/S) were 42·02 mg l^?1 d^?1 and 26·89 mg g^?1, respectively. Conclusions: The optimal culture conditions we proposed in this study enhanced the EPS production of A. mellea from submerged cultures. Significance and Impact of the Study: The optimal culturing conditions we have found will be a suitable starting point for a scale‐up of the fermentation process, helping to develop the production of related medicines and health foods from A. mellea.     

Biosynthesis of patulin. Dehydrogenase and dioxygenase enzymes of penicillium patulum

Two aromatic dehydrogenases catalyzing the reversible conversions of gentisyl alcohol and m-hydroxybenzyl alcohol to their corresponding aldehydes have been partially purified. These partially purified dehydrogenases were shown to require NADPH. In the case of the gentisyl alcohol-gentisaldehyde interconversion, a 46-fold purification was achieved using POLYCLAR AT and DEAE-cellulose chromatography.A cell-free system capable of converting gentisaldehyde to patulin was prepared with a pH optimum of 8.0. The system was dependent on O₂ and NADPH, was stimulated by ATP and inhibited by the Fe²⁺ chelators, α, α-dipyridyl and o-phenanthroline. These results suggest a dioxygenase mechanism for patulin synthesis from gentisaldehyde.     

Fat synthesis from supplemented beet molasses by penicillium soppi zaleski in still and shaken cultures

Media composed of molasses alone did not support good growth nor high fat formation even when used at high concentrations. Peptone supplement as an external source of nitrogen accelerated both growth and fat formation in still as well as in shake cultures. But shaking mankedly suppressed growth and fat formation in media of molasses alone or molasses and peptone.Addition of corn steep liquor (CSL) to molasses gave rise in still cultures to rapid growth that was further accelerated by shaking. Effect of CSL supplement on fat formation, as measured by fat percentage in dry mycelium, was suppressive in still cultures. In shaken cultures, fat formation was promoted by the lowest concentration only. With higher concentrations of CSL, fat content increased but fat percentage in mycelium decreased.     

Hemagglutinating activity in extracts of mycelia from submerged mushroom cultures.

Extracts from mycelia of seven different mushrooms agglutinated erythrocytes of several species. More than one agglutinating factor was identified in the extracts of three different mycelia. Agglutination was partially inhibited nonspecifically by high concentrations of glucose, galactose, mannose, fucose, and rhamnose.     

Alginate oligosaccharides as enhancers of penicillin production in cultures of penicillium chrysogenum

Oligosaccharide fragments were prepared by partial acid hydrolysis of sodium alginate and consisted of oligomannuronate (OM) and oligoguluronate (OG) blocks. Effects of the OM and OG blocks on penicillin G production by P. chrysogenum were investigated. The oligosaccharides were found to cause significant increases in penicillin G yields. OM blocks at concentrations 10 to 100 mug/mL were used to further evaluate the effects of the oligosaccharides, and were found to enhance the production of penicillin G in shaken flask cultures of P. chrysogenum P2 (high penicillin producer) and NRRL 1951 (low penicillin producer) at the test concentrations. There was an approximately 50% maximum increase in penicillin G yield from biomass in P. chrysogenum P2 cultures and 150% in P. chrysogenum NRRL 1951 cultures, when compared to control cultures without the oligosaccharides. (c) 1997 John Wiley & Sons, Inc.