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431.
Aims: Human bifidobacteria are more sensitive to external environmental factors than animal bifidobacteria, and it is difficult to ensure their stable survival in yogurt. The purpose of this investigation was to observe the survival of human bifidobacteria in yogurts produced under various production conditions.
Methods: Frozen or lyophilized bifidobacteria starters containing Bifidobacterium longum BB536 originally isolated from an infant, and commercial lyophilized yogurt starters were used for yogurt preparation. After producing yogurts under various conditions, the survival of bifidobacteria in these yogurts over various storage periods was observed.
Results: Although there were some differences in bifidobacterial survival in yogurt between various production conditions, more than 1·0 × 107 CFU g−1 of Bif. longum survived in yogurt after 35 days' storage at 5°C. Lower fermentation temperature (37°C) and inclusion of Lactococcus lactis in the starter significantly ( P < 0·05) improved survival of Bif. longum in the yogurt.
Conclusion: In this investigation, the human bifidobacterial strain Bif. longum survived adequately in yogurt, although the fermentation temperature and starter composition affect bifidobacterial survival.
Significance and Impact of the Study: This investigation indicates that stable probiotic yogurt using human bifidobacteria can be produced by choosing optimal production conditions. 相似文献
Methods: Frozen or lyophilized bifidobacteria starters containing Bifidobacterium longum BB536 originally isolated from an infant, and commercial lyophilized yogurt starters were used for yogurt preparation. After producing yogurts under various conditions, the survival of bifidobacteria in these yogurts over various storage periods was observed.
Results: Although there were some differences in bifidobacterial survival in yogurt between various production conditions, more than 1·0 × 10
Conclusion: In this investigation, the human bifidobacterial strain Bif. longum survived adequately in yogurt, although the fermentation temperature and starter composition affect bifidobacterial survival.
Significance and Impact of the Study: This investigation indicates that stable probiotic yogurt using human bifidobacteria can be produced by choosing optimal production conditions. 相似文献
432.
The structure of the retina, the distribution of ganglion cells, and the extent of the tapetum lucidum were studied in Dall's porpoise ( Phocoenoides dalli ) with the aim of understanding the role vision plays in this species of cetacean. The basic organization of the retina was similar to that of other vertebrates. Average ganglion cell size was 21.5 μm. The distribution of the ganglion cells in the retina was not even and there were two high-density areas, one in the temporal and one in the rostral part of the retina. Retinal resolving power was estimated using a terrestrial animal model incorporating the density of ganglion cells and other morphological data. The resolving power in the right eyes of two individuals was 2.60 and 2.64 cycles per degree. These values were close to those of other oceanic cetaceans, but inferior to those of terrestrial mammals. On the basis of amino acid analyses, it was shown that the choroid tapetum lucidum in Dali's porpoise contained collagen. The tapetum lucidum was thick at the fundal but thin at the peripheral part of the choroid. 相似文献
433.
《Archives of animal nutrition》2013,67(6):467-476
Abstract The study was conducted to evaluate effects of dietary supplementation with Ligustrum lucidum (LL, 10 g/kg), Schisandra chinensis (SC, 10 g/kg), LL (10 g/kg) + mannan oligosaccharides (MOS, 50 mg/kg), or SC (10 g/kg) + MOS (50 mg/kg) on growth performance and parameters of antioxidative and immunological status of broilers. The results showed that feeding LL, SC, LL + MOS, or SC + MOS had no significant effect on growth performance of broilers relative to the control. However, compared to the control, LL, SC, LL + MOS, or SC + MOS significantly decreased malondialdehyde concentration in serum, thigh, and heart of broilers. In addition, glutathione reductase activity of heart and sera of the birds were significantly elevated by supplementation LL, SC, LL + MOS, or SC + MOS. Furthermore, LL, SC, LL + MOS, or SC + MOS significantly improved antibody titres against Newcastle disease virus and lymphocyte proliferation of broilers (p < 0.05). Whereas, no cooperating effect between LL (or SC) and MOS on antioxidant status and immunity of broilers were found. 相似文献
434.
Responses of mycelia ofGanoderma lucidum to vanadium, selenium and germanium were examined over a wide range of concentrations (10–1, 120 μg/ml) in pure culture.
Se and V were found to be highly toxic, but Ge was not toxic at the levels tested.Ganododerma lucidum cultivated on substrates of sawdust with V (30–80 μg/g) developed mature fruitbodies, but the bioaccumulation of V was quite
low (2.5–7 μg/g in pileus, 12.5–21.5 μg/g in stipe and <1 μg/g in basidiospores). Se as Na2SeO4 labeled with75Se was effectively taken up from substrates and accumulated in fruitbodies (mainly in pileus), then depleted by discharge
of basidiospores. Ge as GeCl4 labeled with77Ge was easily uptaken and translocated into fruitbodies. 相似文献
435.
436.
【背景】灵芝被纳入我国“药食同源”试点名单,腺苷作为其主要活性物质之一,在免疫调节、抗炎、抗癌等方面发挥着重要作用。【目的】调控腺苷生物合成关键酶基因的表达来提高灵芝腺苷产量。【方法】将不同培养时间阶段腺苷合成酶基因(包括5-氨基咪唑-4-甲酰胺核糖核苷酸甲酰转移酶GlATIC、嘌呤核苷磷酸化酶GlPNP、腺苷激酶GlADK)的表达量与腺苷含量相关联,筛选出与灵芝腺苷含量呈正相关的关键酶基因。克隆关键酶基因并在灵芝中过表达,探究关键酶基因过表达对灵芝腺苷积累的影响。【结果】GlPNP的表达与灵芝腺苷含量呈正相关。GlPNP的cDNA全长为969 bp,预测GlPNP蛋白的相对分子量为34.6 kDa,呈三聚体的四元结构。研究结果表明,过表达菌株中GlPNP的表达量在第4天比野生型菌株(WT)上调了2.9-3.9倍,与含空载体的菌株(CK)相比,腺苷含量分别提高了78%和63%。【结论】过表达嘌呤核苷磷酸化酶是提高灵芝腺苷产量的一种有效手段。 相似文献