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101.
严春  初众 《昆虫学报》2008,51(8):804-809
对洋虫Martianus dermestoides Chevrolat成虫脱脂蛋白酶解液的抗氧化作用进行了研究。用木瓜蛋白酶水解洋虫成虫脱脂蛋白,用截留分子量分别为10 kDa和6 kDa的超滤膜将其分离成3个组分,用邻苯三酚 鲁米诺发光法、DPPH自由基清除法、Fenton法和Oyaizu法,分别测定不同分子量的洋虫成虫脱脂蛋白酶解液清除超氧阴离子自由基、DPPH自由基及羟基自由基的能力。结果表明:洋虫成虫蛋白酶解液3个组分都有很好的清除自由基能力,且还原性较强,以分子量<6 kDa的组分清除效果最佳(P<0.05)。结果揭示洋虫成虫脱脂蛋白酶解液具有很好的抗氧化作用。  相似文献   
102.
Nutrition is commonly a powerful determinant of sexual performance in insects, and recent studies have found this to be the case in Queensland fruit flies (Tephritidae: Bactrocera tryoni Froggatt; 'Q-flies'); male Q-flies allowed to self-regulate intake of yeast hydrolysate, a rich source of amino acids and vitamins used in most mass-rearing programmes (protein) and sucrose (carbohydrate), had greatly enhanced sexual performance compared with males provided only sucrose. While some yeast hydrolysate is clearly beneficial for the sexual performance of adult male Q-flies, the questions of what proportion of yeast hydrolysate in the diet is sufficient to yield full benefits, or is too much, have not yet been addressed. To address these questions, the present study assessed sexual performance and longevity of adult male Q-flies maintained on diets containing various proportions of yeast hydrolysate and sucrose. Male Q-flies maintained as adults on dry mixtures containing 9%, 17% or 25% yeast hydrolysate had mating probability, mating latency, copula duration and longevity similar to those provided yeast hydrolysate and sucrose in separate dishes and allowed to self-regulate intake. As in previous studies, while longevity was unaffected we found a marked reduction in sexual performance when the flies were completely denied access to yeast hydrolysate, and the few that did mate had relatively short copulations. At the other extreme, flies receiving diets with high levels of yeast hydrolysate (50%, 75%, 83% and 91%) suffered marked reductions both in longevity and in mating performance.  相似文献   
103.
Candida guilliermondii FTI 20037 cells were entrapped in Ca-alginate beads and used for xylose-to-xylitol bioconversions during five successive batches in a stirred tank reactor. Supplemented sugarcane bagasse hemicellulosic hydrolysate was used as the fermentation medium. The average volume of the Ca-alginate beads was reduced by about 30% after the 600 h taken to perform the five bioconversion cycles, thus demonstrating physical instability under the conditions prevailing in the reactor vessel. In spite of this, almost steady bioconversion rates and yields were observed along the repeated batches. In average values, a production of 51.6 g l(-1), a productivity of 0.43 g l(-1 )h(-1) and a yield of 0.71 g g(-1) were attained in each batch, variation coefficients being smaller than 10%.  相似文献   
104.
Aims: Utilization of cheap and readily available agricultural residues as cheap carbon sources for poly(3‐hydroxybutyrate) (PHB) production by Halomonas boliviensis. Methods and Results: Wheat bran was hydrolysed by a crude enzyme preparation from Aspergillus oryzae NM1 to provide a mixture of reducing sugars composed mainly of glucose, mannose, xylose and arabinose. Growth of H. boliviensis using a mixture of glucose (0·75% w/v) and xylose (0·25% w/v) in the medium led to a PHB content and concentration of 45 wt% and 1 g l?1, respectively, after 30 h. A similar PHB concentration was attained when H. boliviensis was grown on wheat bran hydrolysate but with a lower PHB content, 34 wt%. In a batch cultivation mode in a fermentor, using 1·8% (w/v) reducing sugars, the maximum PHB accumulation by H. boliviensis was attained in 20 h, but was reduced to about 30 wt%. By adding butyric acid (0·8% v/v), sodium acetate (0·8% w/v) and decreasing the reducing sugars concentration to 1·0% w/v in the medium, PHB accumulation and concentration were increased to 50 wt% and 4 g l?1, respectively, after 20 h. Butyric acid and sodium acetate for PHB production could also be provided by anaerobic digestion of solid potato waste. Conclusions: Cheap and readily available agricultural residues can be used as substrates to produce PHB. The production of PHB by H. boliviensis using wheat bran hydrolysate as source of carbon is expected to reduce the production cost and motivates further studies. Significance and Impact of the Study: Large‐scale commercial utilization of PHB is mainly hampered by its high production cost. Carbon source for PHB production accounts up to 50% of the total production costs. Thus, the use of waste agricultural residues can substantially reduce the substrate cost (and in turn even provide value to the waste), and can downsize the production costs. This improves the market competitiveness. Studies on PHB production by moderate halophiles were recently initiated with H. boliviensis and findings show that it has potential for commercial exploitation. PHB production by H. boliviensis using wheat bran and potato waste is hence interesting.  相似文献   
105.
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107.
目的:探讨脑蛋白水解物对缺血性脑血管病患者血流动力学、血脂水平及神经功能的影响。方法:92例缺血性脑血管病患者依据抽签法分作对照组与观察组,各46例,对照组采用常规治疗,观察组在常规治疗基础上结合脑蛋白水解物治疗,观察并比较两组患者的全血低切黏度、全血高切黏度、血浆黏度、红细胞压积、纤维蛋白原、总胆固醇(TC)、甘油三脂(TG)、低密度脂蛋白(LDL-C)高密度脂蛋白(HDL-C)、神经功能、脑血管储备能力、屏气指数以及临床效果。结果:治疗后,两组血流动力学均低于治疗前,且观察组低于对照组(P0.05);两组TC、TG、LDL-C均低于治疗前,且观察组低于对照组(P0.05);两组HDL-C均高于治疗前,且观察组高于对照组(P0.05);两组NIHSS均低于治疗前,且观察组低于对照组(P0.05);两组脑血管储备能力及屏气指数均高于治疗前,且观察组高于对照组(P0.05)。观察组治疗有效率高于对照组,差异具有统计学意义(P0.05)。结论:脑蛋白水解物可有效调节缺血性脑血管病患者血流动力学及血脂水平,改善神经功能。  相似文献   
108.
A detoxification method using activated charcoal with concentrated rice straw hemicellulosic hydrolysate improved the conversion of xylose to xylitol by the yeast Candida guilliermondii by 22%. This was achieved when the hydrolysate:charcoal ratio was 40 g g–1, resulting in removal of 27% of phenolic compounds. Under this condition, the xylitol yield factor (0.72 g g–1) and volumetric productivity (0.61 g l–1 h–1) were close to those attained in a semi-defined medium simulating hydrolysate sugars.  相似文献   
109.
比较研究了用碘量法和分光光度法测定角蛋白水解液中L-胱氨酸含量的适用性。结果表明,磺量法不适用于水解液中L-胱氨酸含量的测定。分光光度法不仅适用于水解液中L-胱氨酸含量的测定,同时也适用于产品L-胱氨酸含量的测定,测定结果准确可靠,相对误差为0.29%~0.84%。  相似文献   
110.
为探究鲍鱼内脏酶解物对辣椒素诱导的系统低度炎症模型小鼠炎性因子、肠道菌群及短链脂肪酸的影响,将30只雄性小鼠随机分为6组:空白对照组、辣椒素致炎模型组、鱼油对照组、鲍鱼内脏酶解物低、中、高剂量组(0.30、0.60、1.20 g/(kg·d)),干预7 d后,ELISA法检测小鼠血清中肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、白细胞介素-10(IL-10),鲎试剂法测定小鼠血清中细菌脂多糖(LPS)的含量,16S rRNA基因高通量测序和生物信息学方法考察小鼠肠道菌群的结构组成,GC-MS法测定小鼠粪便中短链脂肪酸的含量。结果显示,辣椒素模型组小鼠血清中TNF-α、IL-6和LPS含量显著升高,肠道菌群OTUs数显著降低,菌群各门、属水平比例存在显著变化,其中寡养单胞菌属(Stenotrophomonas)和棒状杆菌属(Corynebactrium)等有害相对丰度显著增加,粪便中的乙酸、丙酸以及总短链脂肪酸含量显著降低,异戊酸含量显著升高,而经鲍鱼内脏酶解物干预后,小鼠血清中IL-1β、IL-6和LPS含量显著降低,肠道中乳杆菌属(La...  相似文献   
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