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101.
Fifty-five bacteriocinogenic lactic acid bacteria (LAB) isolated from seven different sources. Eight isolates were found to
produce pediocin PA-1 like bacteriocin as detected by pedB gene PCR and dot-blot hybridization. The culture filtrate (CF) activity of these isolates exhibited strong antilisterial,
antibacterial activity against tested food-borne pathogens and LAB. The identification and genetic diversity among the selected
LAB was performed by conventional morphological and molecular tools like RFLP, RAPD, and 16S rDNA gene sequencing. The isolates
were identified as, 1 each of Pediococcus acidilactici Cb1, Lactobacillus
plantarum Acr2, and Streptococcus equinus AC1, 2 were of P. pentosaceus Cb4 and R38, and other 3 were Enterococcus
faecium Acr4, BL1, V3. Partial characterization of the bacteriocins revealed that the peptide was heat-stable, active at acidic to
alkaline pH, inactivated by proteolytic enzymes, and had molecular weight around 4.6 kDa and shared the properties of class
IIa pediocin-family. The bacteriocin production at different temperatures, pH, and salt concentrations was studied to investigate
the optimal condition for application of these isolates as a starter culture or as a biopreservative in either acidic or non-acidic
foods. 相似文献
102.
目的研究长爪沙鼠发情周期,揭示发情规律,优化判定方法。方法连续18 d采集50只长爪沙鼠阴道上皮脱落细胞涂片,采用角化细胞计数法研究长爪沙鼠发情周期规律。比较瑞氏染色、HE染色和直接镜检判定发情周期4个时相的优缺点。结果长爪沙鼠的发情周期有稳定型、不稳定型、假孕三种类型。其中稳定型占68.6%,发情周期为(106.3±35.0)h,可分为4个时相。4个时相角化细胞的比例分别为发情前期(13.5±7.8)%、发情期(86.7±9.9)%、发情后期(27.9±12.8)%和发情间期(3.3±2.8)%。结论角化细胞计数能准确地判定长爪沙鼠的发情周期及各个时相。直接镜检法能快速反映阴道脱落细胞的形态。 相似文献
103.
Modulatory effect of quercetin on azathioprine induced toxic changes was studied in spleen of experimental animals. Azathioprine treatment caused an increase in serum albumin/globin ratio and a decrease in total protein in spleen tissue. An increase in a membrane bound ATPases was also noted. Supplementation of quercetin with azathioprine increased the protein content and lowered the activities of membrane ATPase in spleen. There was a decrease in serum albumin globulin ratio. It was concluded that quercetin modulated the protein and membrane bound ATPase activities and protected the spleen from azathioprine induced membrane damage. 相似文献
104.
Culture and regeneration of mesophyll-derived protoplasts of sorghum [Sorghum bicolor (L.) Moench] 总被引:1,自引:0,他引:1
R. V. Sairam N. Seetharama P. S. Devi A. Verma U. R. Murthy I. Potrykus 《Plant cell reports》1999,18(12):972-977
A protocol for plant regeneration from mesophyll/protoplasts of sorghum [Sorghum bicolor (L.) Moench] was developed. The yield of intact protoplasts, their subsequent divisions and regeneration were genotype-dependent.
The genotype 296B was always more responsive than IS 32266. For 296B, the sixth leaf from 18-day-old plants kept in dark for
2 days before harvesting was found to be the most suitable source of viable protoplasts. The first division was observed 10–12
days after plating, and the second division after 12–14 days. The maximum plating efficiency was 4.8% in 296 B, followed by
2.48% in IS 32266. Microcolonies were visible after 25–30 days, and microcalli after 60–75 days. Whole plants were obtained
after 6–8 weeks of culture of microcalli on MS medium containing 0.2 mg l–1 kinetin and 2 mg l–1 BAP. The frequency of regeneration in 296B and IS 32266 was 12.80% and 10.58%, respectively. Ten plants transferred to pots
in the glasshouse established well. The seeds collected from glasshouse-grown plants were sown in the field where plants were
grown to maturity.
Received: 7 October 1998 / Revision received: 13 January 1999 / Accepted: 20 January 1999 相似文献
105.
Ravi Kiran T Subramanyam MV Asha Devi S 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2004,137(2):187-196
We examined a suitable swim program of different intensities and durations that could evoke changes in the myocardial antioxidant capacity in 22-month-old rats. Male rats (Rattus norvegicus) were assigned to either a sedentary control (SE-C) group or one of six trainee groups. Animals were swim-exercised for 4 weeks with either 20 min or 40 min/day, and three intensities, low, moderate and high. Low-intensity at 20 min/day elicited maximum swim velocity (Sv) and endurance capacity (P<0.05). While serum total cholesterol, triglyceride and low-density lipoprotein (LDL-C) levels were significantly reduced, high-density lipoprotein (HDL-C) showed an increase (P<0.05) in low-intensity trained rats (20 min/day) over SE-C. Notable reduction in blood lactate was also evident. Exercise training significantly increased superoxide dismutase (Mn-SOD), decreased lipid peroxidation products, malondialdehyde and lipofuscin in the left and right ventricles. Increased Mn-SOD with concomitant decrease in lipofuscin in left ventricle was significantly greater than in right ventricle. Moderate- to high-intensity exercise was not effective in either reducing lipid peroxidation products or elevating Mn-SOD activity. These data suggest that swim training at low-intensity of 20 min/day is beneficial as a major protective adaptation against oxidative stress in old myocardium. 相似文献
106.
Following isoproterenol treatment mitochondrial lipid peroxidation, phosphoslipase activity, lactate and calcium increased significantly, while activities of tricarboxylic acid cycle enzymes, enzymes of respiratory chain and ATP production showed decline. Oxidative phosphorylation was also affected on isoproterenol treatment with significant reduction in all the variables. Fish oil pretreatment in isoproterenol treated rats showed improved mitochondrial energy metabolism. The results suggest cardioprotective effect of fish oil. 相似文献
107.
The present study was conducted to elucidate the antioxidant role of an ayurvedic formulation Abana in isoproterenol induced myocardial infarction in rats. In myocardial necrosis induced by isoproterenol, a significant increase in serum iron content with a significant decrease in plasma iron binding capacity, ceruloplasmin activity and glutathione level were observed. There was also a significant increase in lipid peroxides levels on isoproterenol administration. Activities of antioxidant enzymes like superoxide dismutase, catalase, glutathione peroxidase, glutathione-s-transferase, glutathione reductase were decreased significantly in heart with isoproterenol-induced myocardial necrosis. Abana, produced a marked reversal of these metabolic changes related to myocardial infarction induced by isoproterenol. In conclusion ayurvedic formulation Abana exerts its effect by modulating lipid peroxidation and enhancing antioxidant and detoxifying enzyme systems. 相似文献
108.
Aerides vandarum and Vanda stangeana are two rare and endangered vandaceous orchids with immense floricultural traits. The intergeneric hybrids were synthesized
by performing reciprocal crosses between them. In vitro germination response of the immature hybrid embryos was found to be
best on half-strength Murashige and Skoog medium supplemented with 20% (v/v) coconut water/liquid endosperm from tender coconut. Determination of hybridity was made as early as the immature seeds or
embryos germinated in vitro, using randomly amplified polymorphic DNA (RAPD) markers. Out of 15 arbitrarily chosen decamer
RAPD primers, two were found to be useful in amplification of polymorphic bands specific to the parental species and their
presence in the reciprocal crosses. However, a decisive profile that can identify the reciprocal crosses could not be provided
by RAPD. Amplification of the trnL-F non-coding regions of chloroplast DNA of the parent species and hybrids aided easy identification of the reciprocal crosses
from the fact that maternal inheritance of chloroplast DNA held true for these intergeneric hybrids. Subsequent restriction
digestion of the polymerase chain reaction (PCR) amplified trnL-F non-coding regions of chloroplast DNA also consolidated the finding. Such PCR-based molecular markers could be used for
early determination of hybridity and easy identification of the reciprocal crosses. 相似文献
109.
Summary Studies on the survival ofPseudomonas solanacearum, the causal agent of bacterial wilt of tomato, under laboratory conditions showed that soil amendments had little effect
on the population of the pathogen. When the host plant was grown in amended soil there was a positive influence on growth
of the pathogen. The population level of the pathogen incorporated into the soil was reduced to one-half within a period of
46 days.
The pathogen survived in the rhizosphere of non-host plants belonging to the families Acanthaceae and Leguminosae even in
the absence of the natural hosts, but its incidence in the rhizosphere of plants belonging to Graminae and Cyperaceae was
comparatively low indicating possibilities of reducing the inoculum potential of the pathogen in tomato fields by allowing
such plants to grow during fallow periods.
Part of the thesis of the Senior Author presented to the Kerala Agricultural University, Trichur, Kerala State, India. 相似文献
110.
目的观察非酒精性脂肪肝(NAFLD)大鼠肝组织中PPARα基因的表达,并用PPARct激动剂进行干预,探讨其与胰岛素抵抗、脂代谢紊乱的关系。方法大鼠随机分为①正常对照组、②高脂模型组、③PPARα激动剂干预组,利用高脂饮食建立大鼠非酒精性脂肪肝模型。12周后,检测大鼠血脂、肝功能、血糖、胰岛素水平及胰岛素抵抗指数;RT-PCR法分析PPARα基因的表达;观察肝脏的形态学改变。结果PPARa激动剂可降低NAFLD大鼠转氨酶、血脂水平及胰岛素抵抗指数,可促进NAFLD大鼠中PPARa基因的表达;肝脏形态学明显改善。结论PPARα激动剂能改善NAFLD大鼠脂质代谢紊乱,有明显的保肝降酶作用,具有适度的胰岛素增敏作用。PPARα及其配体在NAFLD发病机制及治疗中的进一步深入研究,将为临床防治NAFLD提供新的思路。 相似文献