共查询到19条相似文献,搜索用时 62 毫秒
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正交试验优化天然虾青素的提取工艺研究 总被引:2,自引:1,他引:1
研究了负压空化法提取虾壳中虾青素的各项工艺条件对虾青素提取效果的影响,通过正交试验确定了负压空化法提取最佳工艺参数为提取溶剂是浓度80%的乙醇溶液,提取时间为35min,料液比为1:20,通气量为0.2m^3·h^-1。同时将负压空化法与常用破壁提取方法的提取效果和效率进行了比较,综合结果表明,负压空化法优越于其它方法,是一种能够适应工业生产的新型提取方法。 相似文献
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以贵州草海自然水域捕获的新鲜小龙虾(Procambarus clarkii)为材料,采用单因素实验研究了提取溶液、料液比、提取温度、提取时间、提取次数对虾青素提取效果的影响,用分光光度法测定了草海小龙虾不同部位虾青素的含量。结果表明,以乙酸乙酯为提取溶液,料液比为1∶2(g∶mL),在60℃下提取2 h,重复提取两次,再此提取条件下虾壳中虾青素含量最高。在虾壳、虾肉和内脏三个部位中,虾壳中虾青素含量最高,虾肉和内脏中也含有少量虾青素,但是含量远低于虾壳中的含量,说明了小龙虾虾青素主要富集在虾壳中。 相似文献
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内源酶辅助提取虾壳虾青素的研究 总被引:1,自引:0,他引:1
文章探讨了内源酶对虾青素提取效果的影响,并以高效液相色谱法(HPLC)测定样品中虾青素的质量浓度,研究了pH、温度和酶解时间这3个因素对虾青素提取效果的影响,采用正交试验进行优化,以虾壳虾青素的萃取率作为评价提取效果的指标。结果表明,当酶解最佳工艺条件为pH 4.0,温度50℃,酶解时间1.5 h时,虾青素的萃取率最高,可达32.16μg.g-1湿虾壳,比直接超声提取提高28%。通过空白试验可知,外加脂肪酶对虾青素提取无促进作用,仅利用内源酶即可达到较好的提取效果,且经济节约。 相似文献
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虾青素生物学来源和功能的研究进展 总被引:16,自引:0,他引:16
虾青素(Astaxanthin)即3,3’—二羟基-4,4’二酮基-β,β’胡萝卜素,又称虾黄质、虾黄素、龙虾壳色素、还原型虾红素。虾青素的分子式为C40H52O4,是一种萜烯类非维生素A源胡萝卜素,呈艳丽的红色,易溶于二硫化碳、丙酮、苯和氯仿,因其具有着色功能和极强的抗氧化性,提高免疫力;近年来越来越受到国内外食品、医药、化妆品、养殖、饲料等领域研究人员的重视。1虾青素的生物学来源虾青素在动物体内和羽毛中,尤其是水生动物体内(如虾、蟹)普遍存在。早在20世纪30年代虾青素就已从虾、蟹中分离出来。除了从水产品加工的废弃物中提取虾青素外,从… 相似文献
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为筛选到海洋来源的淀粉酶,采用Yoo改良法测酶活,对从浙江舟山群岛海域潮间带海泥样中筛选到的一株玫瑰暗黄链霉菌A46进行选育,通过紫外线和DES诱变处理,得到一株酶活为105.6 U/m L的突变株,该突变株酶活提高213.3%,经过10次传代,酶活仅下降3.6%,是一株性状稳定的优良菌株。在单因素实验的基础上应用Plackett-Burman实验设计和响应面分析方法(RSA)对该菌株的发酵条件进行系统优化,得到优化发酵条件:培养温度33℃、接种量2.25%、盐度23.4、初始p H值为8、转速200 r/min、装瓶量为20%、淀粉含量为0.5%、培养时间为72 h。研究表明,在此条件下的酶活为125.8 U/m L,酶活比优化前提高了19.1%。 相似文献
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A marine antagonistic bacterium, JG1, was isolated from rearing water of healthy turbot (Scophthalmus maximus) in Qingdao, China. Strain JG1 was Gram‐negative, straight rod and motile by polar flagella. The colony, when cultured for 24 h under room temperature, produced a yellow pigment. On the basis of morphological, physiological and biochemical characteristics, along with 16S rDNA sequence analysis, JG1 was identified as Pseudoalteromonas flavipulchra. JG1 had good inhibitory effects on several bacterial pathogens of aquaculture in the genus Vibrio (V. anguillarum, V. alginolyticus, V. campbellii, V. harveyi, V. mimicus, V. parahaemolyticus and V. tubiashii) and Aeromonas (A. hydrophila and A. salmonicida). No mortality occurred 14 days after zebra fish and 7 days after mantis shrimp were intraperitoneally injected with JG1 at 106 CFU per animal, and 7 days after scallop and clam were immersed in JG1 at 107 CFU mL?1. A good antagonistic effect on several bacterial pathogens and nontoxicity to the above‐mentioned animals make JG1 a potential probiotic in aquaculture. In addition, a fast detection technique based on polymerase chain reaction amplification of the gyrB gene was established to allow us to determine the fate of JG1 when it is applied in aquaculture in the future. 相似文献
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鳗草根际固氮菌的分离鉴定及培养条件的筛选 总被引:1,自引:1,他引:0
为了解鳗草(Zostera marina)根际微生物的共生固氮功能,并分离得到对海草有潜在促生效果的功能微生物,以山东荣城天鹅湖鳗草为研究对象,采用选择性固氮培养基从其根际分离得到了两株具较高固氮酶活性的菌株(3A和4G),从形态学、生理生化特性、16S rDNA和固氮基因nifH等方面对菌株进行筛选和鉴定,探讨菌株的最佳培养条件并获得了菌株典型生长曲线。结果表明,菌株3A为海旋菌(Thalassospira),革兰氏阳性菌,菌落圆形桔黄色,可利用的碳源:D-甘露糖,D-松三糖,L-鼠李糖等,最佳培养条件:盐度2.585%,pH 8.18,温度31.49℃;菌株4G为芽孢杆菌(Bacillus),革兰氏阴性菌,菌落圆形乳白色,可利用的碳源:D-纤维二糖,D-葡萄糖,D-麦芽糖,蔗糖,D-甘露醇,D-海藻糖等,最佳培养条件:盐度2.920%,pH 7.99,温度37.27℃。利用乙炔还原法测定二者的固氮酶活性,分别为252.21 nmol C_2H_4/(mL·h)和196.31 nmol C_2H_4/(mL·h)。研究证实两株菌株具有良好的固氮性能,可用于海草固氮肥的研制,在海草床生态系统恢复研究领域具有潜在的应用前景。 相似文献
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从合浦珠母贝(Pinctada fucata)粘液中分离纯化得到一株抗菌物质产生菌F9,利用16SrDNA方法鉴定该菌株为棒状乳杆菌(Lactobacillus coryniformis)。通过琼脂扩散法测定了该菌的抑菌谱,发现该菌发酵液上清液在排除有机酸和过氧化氢(H2O2)的影响后仍对金黄色葡萄球菌(Staphyloccocus aureus)等多种食源性致病菌有明显的抑菌作用。对该菌发酵液抑菌物质进行超滤分析及蛋白酶处理,可推断该抗菌物质为分子量在5~10kDa的蛋白类物质。 相似文献
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合浦珠母贝DNA的抽提和RAPD反应体系的优化 总被引:9,自引:5,他引:9
分别从保存于-70℃和95%乙醇的合浦珠母贝组织提取总DNA。结果表明,乙醇保存标本用双蒸馏水预处理后所提的DNA与-70℃保存的标本所提的DNA质量均较好。用抽提的DNA为模板优化RAPD条件,得到适合于合浦珠母贝的RAPDPCR反应条件为:20μL反应体系中包括20ngDNA模板,1×PCRBuffer,0.1mmol·L-1dNTPs,2.5mmol·L-1MgCl2,0.2μmol·L-1引物,1UTaqDNA聚合酶。最佳退火温度40℃。PCR产物用非变性PAGE银染和琼脂糖EB染色检测所得到的主要带型相同,但PAGE能检测到更多的多态带。 相似文献
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菌蜕具有完整细菌表面抗原结构, 可诱导机体的体液和细胞免疫应答, 成为疫苗制备的候选之一,为了探讨鳗鲡迟缓爱德华氏菌菌蜕疫苗的可行性, 实验采用基因重组技术构建了噬菌体PhiX174裂解酶基因(Lysis E)的温控表达载体, 转化迟缓爱德华氏菌, 成功制备其菌蜕, 并对菌蜕形态、溶菌动力学、裂解效率以及制备条件等进行了研究。结果表明, 细菌菌蜕表面形成溶菌孔道, 细胞因内容物流失而发生明显的皱缩; 构建的迟缓爱德华氏菌诱导后1 h开始裂解, 5 h后裂解基本完成, 裂解效率为99.99%, 冷冻干燥后重悬涂布平板, 未检出活菌, 电镜观察表明冻干前后细胞形态未见明显变化; 构建的迟缓爱德华氏菌分别在OD600值为0.4和0.6进行诱导, 其裂解过程和裂解效率没有明显区别; 分别用LB、BHI、NB 3种培养基进行比较研究, 其中LB培养基制备的菌蜕细胞较完整、裂解完全, 是制备迟缓爱德华氏菌菌蜕最优培养基。本研究成功构建了鳗源迟缓爱德华氏菌菌蜕, 并对其制备条件进行了优化, 为鳗鲡爱德华氏菌病疫苗开发奠定了基础。 相似文献
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Fish iridovirus causes systemic disease with high morbidity and mortality in various species of wild and farm‐raised fish, resulting in severe economic losses. Recently, frequent outbreaks of iridovirus infection have occurred among cultured fish in many Asian countries, emphasizing the need for a protective vaccine programme or the development of a suitable therapy. In this study, we expressed a recombinant major capsid protein (rMCP) of rock bream iridovirus (RBIV) from yeast using codon optimization. The rMCP in yeast was added to feed in an attempt to induce intestinal mucosal immunity for protection against and/or to reduce the severity of fish iridovirus infection. We found that fish immunized orally with rMCP underwent a successful induction of antibodies (P < 0.05) and were protected (P = 0.0001) against viral challenge. Based upon these results, oral administration of immunogenic protein as an antigen can be considered a useful method for implementation of vaccine programmes against iridovirus as well as other marine viral diseases. 相似文献
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Biomass production,proximate composition and fatty acid profile of the local marine thraustochytrid isolate,Schizochytrium sp. LEY7 using low‐cost substrates at optimum culture conditions
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This study was conducted to investigate low‐cost substrate alternative and the optimum culture conditions in mass producing the local marine thraustochytrid, Schizochytrium sp. LEY7 isolated from the mangrove leaves of Baybay, Southern Leyte Philippines. Results showed that Schizochytrium sp. LEY7 is able to utilize commercial grade glucose and yeast extract from NaCl‐treated baker's yeast as source of carbon and micronutrients respectively. Cost of mass producing the thraustochytrid isolate using the alternative production substrates was substantially reduced. Incubation temperature and salinity levels were the two growth factors significantly affecting the biomass production of the isolate. The short duration of lag phase shown by the isolate suggests a growth advantage in that cells are readily able to adapt to their new environment. Total lipids averaged to 19.4%. Principal fatty acids were palmitic acid (C16:0) with 33.52% and docosahexanoic acid (DHA, C22:6n‐3) with 39.92% proportion to total fatty acid. Eicosapentaenoic (C20:5n‐3, 1.01%) and arachidonic (C20:4n‐3, 0.90%) are present but in relatively lower amount. Our findings showed the potential of low‐cost substrate in mass producing the local thraustochytrid isolate, Schizochytrium sp. LEY7 as lipid and polyunsaturated fatty acid source in aquaculture. Biomass production was enhanced by optimizing the culture conditions. 相似文献