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不同叶位桑叶及发酵温度对桑红茶中活性成分含量的影响 总被引:1,自引:0,他引:1
为了进一步提升采用红茶加工工艺制作桑红茶的品质和保健功能,以桑红茶中总黄酮、芦丁、异槲皮苷、总多糖、多酚、1-脱氧野尻霉素(DNJ)、氨基酸等活性成分的含量为考核指标,分析不同叶位桑叶原料及加工制作发酵温度2个重要因素对成品桑红茶中活性成分含量的影响。结果表明,采用第1叶位的桑叶作原料,制备桑红茶的总黄酮、芦丁、异槲皮苷、总多糖、多酚、DNJ和氨基酸等活性物质含量最高,质量比分别为38.497、1.215、1.127、21.510、1.522、1.043、37.660 mg/g;在32℃下发酵,有利于桑红茶中各种活性成分的生物转化和定向积累。依据试验结果并综合其他工艺因素认为,以第1叶位的桑叶为原料,25℃下萎凋4 h,在32℃及相对湿度85%的条件下发酵8 h,可以得到富含各种活性成分的桑红茶。 相似文献
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桑叶茶中的1-脱氧野尻霉素(1-deoxynojirimycin,DNJ)是抑制α-葡萄糖苷酶活性的功能性成分之一,研究基本加工工艺条件以及杀青方法和处理时间、炒干时间等因素对制作桑叶绿茶中DNJ含量的影响,并应用高效液相色谱技术检测桑叶绿茶中的DNJ含量。采用微波加热、蒸汽加热和滚筒加热杀青,均可以使桑叶茶中的DNJ含量提高80%左右(P0.05)。其中,采用微波杀青(1 350 W)150 s,蒸汽杀青2 min,滚筒杀青(255℃)30 s,桑叶茶中的DNJ含量均可达到最高值。后续加工工艺中,揉捻和曲毫流程对桑叶茶中的DNJ含量无显著影响;在125℃加热炒干提香处理15 min后,桑叶茶中DNJ的含量达到最大值,但250℃加热炒干提香15 min,对桑叶茶中DNJ的破坏较大。试验结果表明:杀青方式及加工时间、加工温度等都会导致桑叶茶中DNJ的含量发生变化,应采用适宜的加工方式、加工温度及加工时间,以保证桑叶茶中DNJ含量的稳定性。 相似文献
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为了制作高品质桑叶茶,对河南省引进推广的5个桑树品种制作的桑叶茶进行感官品质鉴定和活性成分分析。从香气、汤色、滋味、叶干茶外形等感官评价来看,以育71-1最好,大十次之。从活性成分分析来看,育71-1的总黄酮、总酚、总生物碱、总还原糖含量及PRAP值最高,分别为14.98 mg/g、33.94 mg/g、1.39 mg/g、4.77%、124.23 mol/g; 8632的DNJ含量最高,为0.85 mg/g;大十的总生物碱、DNJ含量最低,分别为0.75 mg/g、0.49 mg/g;红果2号的总还原糖含量和PRAP值最低,分别为2.27%、70.17 mol/g;农桑14号的总黄酮、总酚含量最低,分别为6.38 mg/g、13.62 mg/g。综合分析认为,育71-1制成的桑叶茶品质最佳。 相似文献
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不同家蚕品种对桑叶中1-脱氧野尻霉素的富集能力调查 总被引:1,自引:0,他引:1
家蚕体内的1-脱氧野尻霉素(DNJ)来源于桑叶,为筛选对食下桑叶中DNJ有较强富集能力的家蚕品种用于功能性食品及药物的开发,以18个家蚕品种和6个桑树品种为材料,采用反相高效液相色谱-紫外检测法测定供试家蚕品种5龄第3天幼虫制备全蚕粉中的DNJ含量。不同地理系统家蚕品种对食下桑叶中DNJ的富集能力存在明显差异,其中日系品种与欧系品种对桑叶中DNJ的富集能力有显著差异(前者DNJ质量分数平均为0.3007%,后者为0.2469%),中系品种的DNJ质量分数平均为0.288 0%,与日系品种与欧系品种之间无显著差异;不同眠性(三眠与四眠)家蚕品种间对桑叶中DNJ的富集能力差异不明显。18个供试家蚕品种中,中系品种797对桑叶中DNJ的富集作用最强,其全蚕粉中的DNJ质量分数达0.4345%。选择6个家蚕品种分别取食不同桑树品种的桑叶,分析全蚕粉中的DNJ含量和桑叶中DNJ含量的相关性,其相关系数为0.826 0,全蚕粉中DNJ含量最高的家蚕品种与桑品种组合为家蚕乌2与陕桑403,其次为家蚕武功土种与甜桑、家蚕798与陕桑403。 相似文献
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本实验测定了春夏秋季不同品种桑叶中多糖、黄酮的含量,结果表明:同一品种桑叶春季的多糖和黄酮含量比夏秋季高;在测定的几个品种中以“粤诱51”桑叶多糖和黄酮含量较高。 相似文献
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59份野生桑桑叶中的DNJ含量及粗提物对α-糖苷酶的抑制活性 总被引:6,自引:2,他引:6
对来自云南省不同地区的59份野生桑桑叶中的1-脱氧野尻霉素(DNJ)含量,以及桑叶粗提物对淀粉酶、蔗糖酶和麦芽糖酶的体外抑制活性进行了测定,同时采用液-质联用(LC-MS)仪分离纯化桑叶粗提物中的DNJ,并对其抑制蔗糖酶的机制进行了初步研究,期望筛选出适用于治疗糖尿病药物开发的药用桑资源,以及为解析桑叶粗提物和纯化的桑叶DNJ抑制α-糖苷酶活性的机制提供线索。研究结果表明:不同来源的野生桑桑叶中的DNJ含量存在明显差异,其中来自开远地区的岩桑桑叶中DNJ的质量分数高达0.791 1%,是具有药用开发价值的野生桑资源;不同来源的野生桑桑叶粗提物对淀粉酶、蔗糖酶和麦芽糖酶活力的体外抑制率差异显著,但抑制活性的大小与样品中的DNJ含量不成正比,推测桑叶中除含有DNJ外还含有具有明显的α-糖苷酶抑制活性的多种DNJ类似物;从野生桑桑叶粗提物中分离纯化的DNJ对淀粉酶无明显抑制活性,但对蔗糖酶和麦芽糖酶有显著的抑制活性,对蔗糖酶表现为非竞争性抑制作用。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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以国际标准强毒R株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离MG,并收集感染鸡所产蛋分离MG。结果表明,人工感染48小时后上、下呼吸道及肺已被全面感染,96小时气囊已被感染,120小时输卵管已能分离到MG,卵巢始终分离不到MG。人工感染鸡自144小时便能在其所产蛋中分离出MG。药物治疗能在72小时内消除感染,油乳剂苗则需24天后逐渐降低蛋内MG分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内MG,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献