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71.
Lactic acid production from agriculture residues   总被引:5,自引:0,他引:5  
Various agriculture feedstock residues were evaluated for lactic acid production by simultaneous saccharification and fermentation (SSF) using Lactobacillus delbrueckii and Lactobacillus plantarum, without any additional nutrients. Lactic acid production was higher in alfalfa fiber and soya fiber compared to corncob (soft) and wheat straw. In Lactobacillus plantarum, the amount of lactic acid obtained from alfalfa fiber and soya fiber was 46 and 44 g/100 g fiber, respectively. However, in Lactobacillus delbrueckii, the lactic acid production in soya fiber was 44 g/100 g fiber and that of alfalfa was 32 g/100 g fiber. Small amounts of acetic acid were also produced from SSF of agricultural feedstocks residues. During SSF of alfalfa fiber, lactic acid production in both L. delbrueckii and L. plantarum was enhanced by adding pectinases and cellulases. Lactic acid production from alfalfa fiber did not change with increasing O2 transfer rates in the fermentation medium, whereas acetic acid production in both Lactobacillus cultures increased with increasing O2 transfer rates.  相似文献   
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A virus inhibiting protein (VI) was isolated from spinach (Spinacia oleracea L.). The VI inhibited infections of test plants with plus- and minus-strand RNA viruses. Inoculation of both local lesion and systemic hosts with TMV in the presence of varying amounts of the VI resulted in typical dose response curves for the number of local lesions or the amount of virus respectively. The lowest concentration of VI leading to a significant reduction in the number of local lesions was 0.06 μg/ml. The VI was found to inhibit local lesion formation only when applied within 2–3 h p.i. but still reduced the number of local lesions when applied up to 9 h prior to virus inoculation. The antiviral activity could be attributed to a protein of molecular weight 29,000 dalton with an isoelectric point of 10.3. Its activity was destroyed by heating for 30 min to 70°C. These characteristics resemble those of other virus inhibiting proteins described for members of the order Caryophyllales such as the Phytolacca inhibitor against which a serological relationship was obtained.  相似文献   
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HgC12-induced renal tubular lesions in the rat present histochemically with a transitory decrease of alkaline phosphatase, adenosinetriphosphatase (ATPase), and leucine-aminopeptidase activity. The toxic alterations of enzyme activity were more pronounced in the pars recta of the proximal tubule and in the loop of Henle, as compared with the tubulus contortus I. L-thyroxine treatment leads to an accelerated reversal of that enzymatic defect, followinga characteristic pattern, and to a differentiating increase of acid phosphatase and ATPase activity in certain parts of the normal renal tubule. The observations are discussed with reference to the specific mode of action of sublimate and l-thyroxine upon the tubular enzymes and to the well-known metabolic and functional influences of thyroid hormone on the kidney.  相似文献   
76.
The regulation of penicillinase synthesis   总被引:5,自引:0,他引:5  
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Nerve growth factor (NGF) serves a critical survival-promoting function for developing sympathetic neurons. Following removal of NGF, sympathetic neurons undergo apoptosis characterized by the activation of c-Jun N-terminal kinases (JNKs), up-regulation of BH3-only proteins including BcL-2-interacting mediator of cell death (BIM)EL, release of cytochrome c from mitochondria, and activation of caspases. Here we show that two small-molecule prolyl hydroxylase inhibitors frequently used to activate hypoxia-inducible factor (HIF) – ethyl 3,4-dihydroxybenzoic acid (DHB) and dimethyloxalylglycine (DMOG) – can inhibit apoptosis caused by trophic factor deprivation. Both DHB and DMOG blocked the release of cytochrome c from mitochondria after NGF withdrawal, whereas only DHB blocked c-Jun up-regulation and phosphorylation. DHB, but not DMOG, also attenuated the induction of BIMEL in NGF-deprived neurons, suggesting a possible mechanism whereby DHB could inhibit cytochrome c release. DMOG, on the other hand, was substantially more effective at stabilizing HIF-2α and inducing expression of the HIF target gene hexokinase 2 than was DHB. Thus, while HIF prolyl hydroxylase inhibitors can delay cell death in NGF-deprived neurons, they do so through distinct mechanisms that, at least in the case of DHB, are partly independent of HIF stabilization.  相似文献   
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