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Kazutaka Sawada Tomoya Sato Hiroshi Hamajima Lahiru Niroshan Jayakody Miyo Hirata Mikako Yamashiro Marie Tajima Susumu Mitsutake Koji Nagao Keisuke Tsuge Fumiyoshi Abe Kentaro Hanada Hiroshi Kitagaki 《Applied and environmental microbiology》2015,81(11):3688-3698
In nature, different microorganisms create communities through their physiochemical and metabolic interactions. Many fermenting microbes, such as yeasts, lactic acid bacteria, and acetic acid bacteria, secrete acidic substances and grow faster at acidic pH values. However, on the surface of cereals, the pH is neutral to alkaline. Therefore, in order to grow on cereals, microbes must adapt to the alkaline environment at the initial stage of colonization; such adaptations are also crucial for industrial fermentation. Here, we show that the yeast Saccharomyces cerevisiae, which is incapable of synthesizing glucosylceramide (GlcCer), adapted to alkaline conditions after exposure to GlcCer from koji cereal cultured with Aspergillus kawachii. We also show that various species of GlcCer derived from different plants and fungi similarly conferred alkali tolerance to yeast. Although exogenous ceramide also enhanced the alkali tolerance of yeast, no discernible degradation of GlcCer to ceramide was observed in the yeast culture, suggesting that exogenous GlcCer itself exerted the activity. Exogenous GlcCer also increased ethanol tolerance and modified the flavor profile of the yeast cells by altering the membrane properties. These results indicate that GlcCer from A. kawachii modifies the physiology of the yeast S. cerevisiae and demonstrate a new mechanism for cooperation between microbes in food fermentation. 相似文献
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This study examined the effects of rhizomes of Alpinia calcarata Roscoe (Zingiberaceae) on male sexual competence and fertility, using a hot water extract (HWE) and rats. Different doses of HWE (150, 250 and 500 mg/kg) were orally administrated to male rats and their sexual behaviour was monitored (for 15 min) 3 h later using receptive females. Fertility was determined in a separate group (with the highest dose) using a noncompetitive copulation test. In the sexual behaviour study, the HWE impaired the number of rats ejaculating and markedly prolonged the latency for ejaculation. Further, the number of rats mounting and intromitting, and the latencies for mounting and intromission were inhibited. Collectively, these observations indicate a strong aphrodisiac action. The other parameters remained unchanged indicating non-impairment in libido, sexual arousability, sexual vigour and sexual performance or penile erectile ability. However, a slight impairment was evident in sexual motivation (with the highest dose) in a partner preference test. In the fertility test, HWE induced profound oligozoospermia but fertility was uninhibited. The highest dose of HWE also elevated the serum testosterone level and the number of spontaneous penile erections rapidly and markedly. Further, the HWE was nontoxic. It is concluded that A. calcarata rhizomes possess a strong and safe oral aphrodisiac activity. 相似文献
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Biotic and abiotic factors that influence the avian distribution in a dry zone wetland was investigated by studying the distribution
of Asian Openbill (Anastomus oscitans), Cotton Pygmy-goose (Nettapus coromandelianus) and Pheasant-tailed Jacana (Hydrophasianus chirurgus) in Anavilundawa Ramsar sanctuary in Sri Lanka in 2006. Their distribution was recorded in Anavilundawa, Suruwila and Maiyawa
reservoirs, their catchments and respective paddy fields, through line transects. The floral cover of surface water was recorded
by floating quadrates. Water lily (Nymphea spp.) was the dominant flora in Anavilundawa reservoir, invasive water hyacinth (Eichhornia crassipes) in Suruwila reservoir and a native lotus (Nelumbo nucifera) in Maiyawa reservoir, respectively. Anavilundawa area had a higher distribution of birds than in the other two areas. Among
the three species observed, Asian Openbill distribution was mainly restricted to Anavilundawa whereas Pheasant-tailed Jacana
was present in all three areas. Nesting of Asian Openbill occurred only in Anavilundawa while nesting of Pheasant-tailed Jacana
was only observed in Maiyawa. Among the three species recorded, Cotton Pygmy-goose numbers were the least. Asian Openbill
preferred dead trees and trees with no leaves for nesting and perching over live trees. It is concluded that the spread of
invasives such as Water hyacinth and Salvinia (Salvinia molesta) forming mats over surface water have reduced the abundance of habitat specialists like Cotton Pygmy-goose. 相似文献
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Shodai Shiroma Lahiru Niroshan Jayakody Kenta Horie Koji Okamoto Hiroshi Kitagaki 《Applied and environmental microbiology》2014,80(3):1002-1012
Saccharomyces cerevisiae sake yeast strain Kyokai no. 7 has one of the highest fermentation rates among brewery yeasts used worldwide; therefore, it is assumed that it is not possible to enhance its fermentation rate. However, in this study, we found that fermentation by sake yeast can be enhanced by inhibiting mitophagy. We observed mitophagy in wild-type sake yeast during the brewing of Ginjo sake, but not when the mitophagy gene (ATG32) was disrupted. During sake brewing, the maximum rate of CO2 production and final ethanol concentration generated by the atg32Δ laboratory yeast mutant were 7.50% and 2.12% higher than those of the parent strain, respectively. This mutant exhibited an improved fermentation profile when cultured under limiting nutrient concentrations such as those used during Ginjo sake brewing as well as in minimal synthetic medium. The mutant produced ethanol at a concentration that was 2.76% higher than the parent strain, which has significant implications for industrial bioethanol production. The ethanol yield of the atg32Δ mutant was increased, and its biomass yield was decreased relative to the parent sake yeast strain, indicating that the atg32Δ mutant has acquired a high fermentation capability at the cost of decreasing biomass. Because natural biomass resources often lack sufficient nutrient levels for optimal fermentation, mitophagy may serve as an important target for improving the fermentative capacity of brewery yeasts. 相似文献
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Typical preparation of seed samples for infrared (IR) microspectroscopy involves imbibition of the seed for varying time periods followed by cryosectioning. Imbibition, however, may initiate germination even at 4° C with associated changes in the chemistry of the sample. We have found that it is possible to section seeds that are sufficiently hard, such as soybeans, on a standard laboratory microtome without imbibition. The use of dry sectioning of unimbibed seeds is reported here, as well as a comparison of different mounting media and modes of analysis. Glycerol, Tissue-Tek, and ethanol were used as mounting media, and the quality of the resulting spectra was assessed. Ethanol was the preferred mountant, because it dried quickly with no residue and thus did not interfere with the spectrum of interest. Analysis in transmission mode using barium fluoride windows to hold the samples was compared with transmission-reflection analysis with sections mounted on special infrared-reflecting slides. The two modes of analysis performed well in different regions of the spectrum. The mode of analysis (transmission vs. transmission-reflection) should be based on the components of greatest interest in the sample. 相似文献
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Danielle B Rodrigues Roger Chammas Natália V Malavasi Patrícia LN da Costa Rosa M Chura-Chambi Keli N Balduino Ligia Morganti 《BMC biotechnology》2010,10(1):19
Background
Theracyte is a polytetrafluoroethylene membrane macroencapsulation system designed to induce neovascularization at the tissue interface, protecting the cells from host's immune rejection, thereby circumventing the problem of limited half-life and variation in circulating levels. Endostatin is a potent inhibitor of angiogenesis and tumor growth. Continuous delivery of endostatin improves the efficacy and potency of the antitumoral therapy. The purpose of this study was to determine whether recombinant fibroblasts expressing endostatin encapsulated in Theracyte immunoisolation devices can be used for delivery of this therapeutic protein for treatment of mice bearing B16F10 melanoma and Ehrlich tumors. 相似文献9.
Sevvandi Jayakody Angela M. Sibbald Robert W. Mayes Russell J. Hooper Iain J. Gordon Xavier Lambin 《European Journal of Wildlife Research》2011,57(4):939-948
Disturbance from human recreational activities may affect the nutrition of free-ranging herbivores due to trade-offs between
feeding in preferred habitats and perceived predation risk. To test this hypothesis, we estimated diet composition for red
deer in the Scottish highlands in spring, when recreational activity tends to be high, and in winter when it is lower. We
analysed faecal samples from three habitat types (grassland, heather moorland and woodland) collected at sites close to a
busy track (disturbed) and at a distance from it (less disturbed). The diet consisted of 39% grasses, sedges, herbs and rushes
(GSHR) and 58% Calluna vulgaris and Erica spp. (heather) in spring, compared with 14% grasses and 77% heather in winter, with small quantities of Vaccinium spp. (berry) and Pinus sylvestris (tree) in both seasons. In spring, faeces from disturbed grass and woodland sites indicated a diet with less GSHR and more
heather and tree than faeces from less-disturbed sites, which could be due to an increased need for vigilance in exposed grassland
and the need to seek cover. In contrast, faeces from all disturbed sites in winter indicated a diet with more GSHR and less
heather than faeces from less-disturbed sites. This could be due to a seasonal decline in recreation and increase in hunting
activity reversing the disturbance levels at the different sites, since hunting is not normally carried out in areas used
by the public for recreation. We conclude that there may be nutritional benefits to deer of reducing disturbance near open
grassland. 相似文献
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T. D. Praveen Tharanga C. M. V. Jinadasa M. F. Risama Priyadarshani Galappatthy R. L. Jayakody Vajira H. W. Dissanayake 《Indian journal of human genetics》2013,19(4):392-396