• Asian-Australasian Journal of Animal Sciences
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• v.20 no.4
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• pp.517-522
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• 2007

The aim of this study was to compare in vitro gas production kinetics, metabolizable energy (ME), organic matter digestibility (OMD) and microbial protein (MP) production of widely used legume hays in ruminant nutrition in Turkey. Gas production were determined at 0, 3, 6, 12, 24, 48, 72 and 96 h and their kinetics were described using the equation p = a+b ($1-e^{-ct}$). There were significant differences among legume hays in terms of chemical composition. The crude protein content of legume hays ranged from 11.7 to 18.6% of dry matter (DM); crude fat from 2.1 to 3.5% DM; neutral detergent fiber from 35.6 to 52.0% DM; acid detergent fiber from 32.0 to 35.5% DM and acid detergent lignin 1.7 to 11.0% DM. Total gas production after 96 h incubation ranged between 61.67 and 76.00 ml/0.200 g of substrate. At 24, 72 and 96 h incubation the total gas production for common vetch were significantly (p<0.01) higher than those of the other legume hays. The ME, OMD and MP of legume hays ranged from 9.09 to 11.12 MJ/kg DM, 61.30 to 75.54% and 90.35 to 138.05 g/kg DM, respectively. The ME, OMD and MP of common vetch was significantly (p<0.01) higher than those of the other hays due to low cell-wall contents and high crude protein. At the end of the experiment, differences in chemical composition of legume hays resulted in the differences in the in vitro gas production, gas production kinetics and the estimated parameters such as ME, OMD and MP. Common vetch can be recommended to hay producers and ruminant breeders, due to high ME, OMD and MP production.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.1
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• pp.28-34
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• 1997

This study was conducted to determine the protein content, cell wall fractions, and mineral concentrations of some minor plant species collected for one year in pastures grazed by goats in the Philippines. An assessment of nutrient variability and a comparison of forage protein and mineral concentrations to the critical value of protein and minerals based on animal needs were also studied. The plant species were the following: grasses(Axonopus compressus, Eleusine indica, Rottboellia exaltata); legumes (Aeschynomene indica, Calopogonium muconoides, Desmodium tortousum); and herbs (Corchorus olitorius, Ipomea aquatica, Sida acuta, Synedrella nodiflora). The two seasons (dry and wet) were subdivided into Dry-1 (December to February, 132 mm total rainfall), Dry-2 (March to May, 25 mm total rainfall), Wet-1 (June to August, 1,138 mm total rainfall), and Wet-2 (September to November, 1,118 mm total rainfall). Results showed that significant differences were obtained on various nutrient fractions including those mineral concentrations across species. Across season, acid detergent lignin (ADL) had higher (p < 0.05) value at Dry-1. Legumes and herbs were higher in crude protein (CP) especially Sida acuta. Grasses showed the highest neutral detergent fiber (NDF) and acid detergent fiber (ADF) with the addition of Sida nodiflora (herb) for it contained high NDF. Aeschynomene indica contained the highest amount of ADL and the herbs (Ipomea aquatica and Sida acuta) had exceptionally high concentration of minerals. Coefficient variation of the various nutrient values ranged from 27.3 to 136.7%. Some forage minerals appeared to be deficient (sodium, phosphorus and copper) or excess (molybdenum) for the whole or part of the year. This study shows that some minor plant species could extend the range of concentration of some nutrients (i.e., CP and minerals) beyond that normally found in conventional pasture species.

• Journal of Microbiology and Biotechnology
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• v.25 no.11
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• pp.1856-1862
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• 2015

In order to improve the stability of endoglucanase under thermal and acidic conditions, the endoglucanase gene was fused to the N-terminus of the Saccharomyces cerevisiae pir gene, encoding the cell wall protein PIR. The fusion gene was transformed into Pichia pastoris GS115 for expression. A resulting strain with high expression and high activity was identified by examining resistance to Geneticin 418, Congo red staining, and quantitative analysis of enzyme activity. SDS-PAGE analysis revealed that the endoglucanase was successfully displayed on the yeast cell surface. The displayed endoglucanase (DEG) showed maximum activity towards sodium carboxyl methyl cellulose at approximately 275 IU/g cell dry weight. DEG exhibited greater than 60% residual activity in the pH range 2.5-8.5, higher than free endoglucanase (FEG), which had 40% residual activity at the same pH range. The highest tolerated temperature for DEG was 70℃, much higher than that of FEG, which was approximately 50℃. Moreover, DEG showed 91.1% activity at 65℃ for 120 min, while FEG only kept 77.8% residual activity over the same period. The half-life of DEG was 270 min at 65℃, compared with only 150 min for FEG. DEG could be used repeatedly at least three times. These results suggest that the DEG has broad applications as a yeast whole-cell biocatalyst, due to its novel properties of high catalytic efficiency, acid-thermal stabilities, and reusability.

• Journal of Microbiology and Biotechnology
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• v.30 no.1
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• pp.62-70
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• 2020

Zygosaccharomyces rouxii is an important yeast that is required in the food fermentation process due to its high salt tolerance. In this study, the responses and resistance strategies of Z. rouxii against salt stress were investigated by performing physiological analysis at membrane level. The results showed that under salt stress, cell integrity was destroyed, and the cell wall was ruptured, which was accompanied by intracellular substance spillover. With an increase of salt concentrations, intracellular Na⁺ content increased slightly, whereas intracellular K⁺ content decreased significantly, which caused the increase of the intracellular Na⁺/K⁺ ratio. In addition, in response to salt stress, the activity of Na⁺/K⁺-ATPase increased from 0.54 to 2.14 μmol/mg protein, and the ergosterol content increased to 2.42-fold to maintain membrane stability. Analysis of cell membrane fluidity and fatty acid composition showed that cell membrane fluidity decreased and unsaturated fatty acid proportions increased, leading to a 101.21% rise in the unsaturated/saturated fatty acid ratio. The results presented in this study offer guidance in understanding the salt tolerance mechanism of Z. rouxii, and in developing new strategies to increase the industrial utilization of this species under salt stress.

• Mycobiology
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• v.36 no.1
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• pp.13-18
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• 2008

Eight distinct bacteria were isolated form diseased mycelia of the edible mushroom, Pleurotus eryngii. 16S rDNA sequence analysis showed that the isolates belonged to a variety of bacterial genera including Bacillus (LBS5), Enterobacter (LBS1), Sphingomonas (LBS8 and LBS10), Staphylococcus (LBS3, LBS4 and LBS9) and Moraxella (LBS6). Among them, 4 bacterial isolates including LBS1, LBS4, LBS5, and LBS9 evidenced growth inhibitory activity on the mushroom mycelia. The inhibitory activity on the growth of the mushroom fruiting bodies was evaluated by the treatment of the bacterial culture broth or the heat-treated cell-free supernatant of the broth. The treatment of the culture broths or the cell-free supernatants of LBS4 or LBS9 completely inhibited the formation of the fruiting body, thereby suggesting that the inhibitory agent is a heat-stable compound. In the case of LBS5, only the bacterial cell-containing culture broth was capable of inhibiting the formation of the fruiting body, whereas the cell-free supernatant did not, which suggests that an inhibitory agent generated by LBS5 is a protein or a heat-labile chemical compound, potentially a fungal cell wall-degrading enzyme. The culture broth of LBS1 was not inhibitory. However, its cell-free supernatant was capable of inhibiting the formation of fruiting bodies. This indicates that LBS1 may produce an inhibitory heat-stable chemical compound which is readily degraded by its own secreted enzyme.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.4
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• pp.483-486
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• 2000

The influence of feed allowance on intake and nutrient utilization by Barbari goats given green maize (Zea mays) and potential feeding value of left-overs were studied. The goats were offered food at 3 levels to give left-overs of about 20% (T-1), 35% (T-2) and 50% (T-3) DM of offered amount. A marked effect of refusal rate on intake and digestibility of nutrients was found. The DMI, g/kg $W^{0.75}$ increased from 39.86 in T-1 to 50.91 and 66.55 g in groups T-2 and T-3, respectively. Allowing selective consumption at higher levels (T-2 and T-3), the intake of TDN and DCP from green maize was found not only to meet the maintenance requirement but provided surplus energy and protein for substantial production. The variability in diet selectivity between goats under different treatments was pronounced. As the level of food excess increased to T-3, the left overs had a higher IVDMD and crude protein and decreased cell wall constituents (p<0.05). Considering the substantial increase in intake and digestibility from feeding green maize at high allowances to goats, further studies are needed to develop practical feeding strategies.

• Mycobiology
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• v.37 no.3
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• pp.161-170
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• 2009

Cryptococcus neoformans is a basidiomycete human fungal pathogen that causes meningoencephalitis in both immunocompromised and immunocompetent individuals. The ability to sense and respond to diverse extracellular signals is essential for the pathogen to infect and cause disease in the host. Four major stress-activated signaling (SAS) pathways have been characterized in C. neoformans, including the HOG (high osmolarity glycerol response), PKC/Mpk1 MAPK (mitogen-activated protein kinase), calcium-dependent calcineurin, and RAS signaling pathways. The HOG pathway in C. neoformans not only controls responses to diverse environmental stresses, including osmotic shock, UV irradiation, oxidative stress, heavy metal stress, antifungal drugs, toxic metabolites, and high temperature, but also regulates ergosterol biosynthesis. The PKC(protein kinase C)/Mpk1 pathway in C. neoformans is involved in a variety of stress responses, including osmotic, oxidative, and nitrosative stresses and breaches of cell wall integrity. The $Ca^{2+}$/calmodulin- and Ras-signaling pathways also play critical roles in adaptation to certain environmental stresses, such as high temperature and sexual differentiation. Perturbation of the SAS pathways not only impairs the ability of C. neoformans to resist a variety of environmental stresses during host infection, but also affects production of virulence factors, such as capsule and melanin. A drug(s) capable of targeting signaling components of the SAS pathway will be effective for treatment of cryptococcosis.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.3
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• pp.35-40
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• 2021

In order to investigate the degree of solubilization of sewage sludge using sono-activated persulfate(UV/PP), VSS reduction rate, solubilization rate and extracellular polymeric substances were measured. Ultrasonic(US) and alkali·ultrasonic method using sodium hydroxide(US/SH) were compared. Under the persulfate·ultrasonic conditions, the VSS reduction rate and the solubilization rate increased to 27.6% and 58.9%, respectively. TB-EPS as Carbohydrate and Protein were extracted by 770 mg/L and 2,162 mg/L. Compared to the other methods, US and US/SH, the VSS reduction rate and solubilization rate were higher. And also, according to the TB-EPS values, cell wall destruction was more efficient.

• Applied Microscopy
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• v.24 no.3
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• pp.67-77
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• 1994

Storage material of endosperm cells digested by various enzymes should be transported to the embryo. At this time, the cellulose of the endosperm cell wall is guessed to be hydrolyzed by the cellulase enabling to transfer the storage material from the endosperm cells to the embryo. Therefore, this study has been carried out to investigate the ultrastructure of endosperm and the localization of the cellase activity on Cannabis sativa L. during germination. Endosperm cells contain a large number of lipid bodies and protein bodies with globoids as the storage material. During gemination they are gradually degenerated, however, the former almost remain until the cells are completely digested. Electron-microscopical reaction products of cellulase on endosperm cells are present. The closer the embryo, the more amount of reaction products on the endosperm cell wall are appeared.

• The Korean Journal of Pharmacology
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• v.25 no.1
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• pp.109-113
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• 1989

Human neutrophil elastase (HNE, EC 3, 4 21, 11), a major causative factor in the induction of pulmonary emphysema, were purified by two steps of liquid chromatography. Purified elastases were cross-reacted with antibody to human neutrophil elastases. Methicillin and cefamandole, which are known as inhibitors of cell wall synthesis of microorganisms, could inhibit the activity of human neutrophil elastase up to 50% with 10mM of both agents and $IC_{50}$ of methicillin was 9.8 mM. Gentamicin, one of the aminoglycosides, also inhibits human neutrophil elastases up to 60% of original activity with 10 mM of this agent and $IC_{50}$ was 9.0 mM. We could demonstrate similar effects in oxytetracycline. 10 mM of oxytetracycline inhibited 95% of human neutrophil elastase and $IC_{50}$ was 0.3 mM. Overall, oxytetracycline, cefamandole and methicillin are strong inhibitors of human neutrophil elastase, and they could be a drug of cholice for the diseases which were known as pathogenesis related to elastase. We also suggest that the mechanism of action of these antibitics are different from the mechanism of antimicrobial effects like inhibition of both cell wall synthesis and protein synthesis.