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为了进一步提高梯棱羊肚菌黑色素的提取率及溶解性,本试验采用单因素、Plackett-Burman试验、响应面试验对纤维素酶-超声波协同提取梯棱羊肚菌黑色素的提取工艺进行优化研究。通过赖氨酸修饰,并对修饰前后的梯棱羊肚菌黑色素进行结构表征、理化性质及稳定性研究。结果表明,在NaOH浓度为1.54 mol/L,纤维素酶添加量为20 mg/g,纤维素酶酶解时间为78.6 min,料液比为1:30,酶解温度为40 ℃,超声时间为80 min条件下提取的梯棱羊肚菌黑色素最优。未修饰的梯棱羊肚菌黑色素不溶于水,色价值为480.24,修饰后的黑色素溶解度为1 016 g/L,色价值为1 771.18,比未修饰的黑色素在溶解性、色价值方面均有所提高。此外,在不同的温度、光照、pH条件下,修饰前后的梯棱羊肚菌黑色素均比较稳定。以上研究结果为梯棱羊肚菌黑色素的高效提取及其产品的开发利用奠定了理论基础。 相似文献
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Interaction between the sequence of feeding of hay and concentrate,and boiling of barley on feed intake,the activity of hydrolytic enzymes and fermentation in the hindgut of Arabian mares
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A. Kiani F. Hoseini P. Ghorbaninejad A. Azarfar M. Kreuzer A. Azizi 《Journal of animal physiology and animal nutrition》2018,102(3):810-817
The interaction between the sequence of feeding of hay and concentrate and the hydrothermal processing of barley in alleviating concentrate effects on intake, and hindgut fermentation in horses was tested. Six Arabian mares (4–10 years of age, 410 ± 35 kg body weight) were used to evaluate the effects of feeding sequence (FS) and type of barley (TB) on intake, and faecal volatile fatty acids (VFA), activities of α‐amylase (AA: EC 3.2.1.1), carboxymethyl cellulase (CMCase: EC 3.2.1.4), microcrystalline cellulase (MCCase: EC 3.2.1.91) and general filter paper degrading activity (FPD). Mares were offered a ration of air‐dried alfalfa and concentrate (70:30 as‐fed) in four subsequent periods of 14 days including 8 days of adaptation and 6 days of sampling. In each period and each meal, mares received concentrate either 30 min after (HC) or 30 min before (CH) alfalfa hay. Barley was either milled or boiled in water. Rectal samples were grabbed directly from rectum once per period. Mares subjected to CH had higher dry matter intakes than mares under HC regime. The acetate:propionate ratio (A:P ratio) in rectal content was higher with CH than HC. The AA activity was higher under CH than under HC. Mares fed boiled barley had lower rectal concentrations of VFA and propionate and a higher A:P ratio than mares fed milled barley. Furthermore, the rectal content showed a higher MCCase activity but a lower AA activity when mares were fed boiled compared with milled barley. Interactions between FS and TB were observed with respect to CMCase activity, and concentrations of propionate and valerate. In conclusion, the present results suggest that both, feeding concentrate before hay and boiling the barley, might improve the hindgut environment in Arabian mares, and that the two measures were mostly additive and sometimes even synergistic. 相似文献
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绿色木霉Fn10-1纤维素酶的分离纯化及酶学特性测定 总被引:1,自引:0,他引:1
试验研究了绿色木霉Fn10-1纤维素酶的初步纯化及酶学性质开展研究。结果表明,该纤维素酶的最适催化温度为70℃,最适pH 7.6,在温度为4~50℃下均能保持较稳定的酶活,高于50℃以后,热稳定性变差,酶活力开始急剧下降。pH在5.6~7.6时该酶有较好的稳定性。Na+、Mn2+、Fe2+、Mg2+、Co2+、Ca2+、Ba2+、Al3+对纤维素酶具有一定的激活作用,Ag+、Fe3+、Cu2+、Zn2+、K+对该酶有一定的抑制作用,其中Cu2+的抑制作用尤为明显。 相似文献
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秸杆栽培食用菌拮抗菌株的鉴定及混菌发酵条件的优化 总被引:1,自引:0,他引:1
从海洋泥样和食用菌发酵料中分离出了32个菌株,从中筛选出了既具有较高的纤维素酶活性又具有对青霉(Penicillium spp)、木霉(Trichoderma spp.)、根霉(Rhizopus)、曲霉(Aspergillus spp)、毛霉(Mucro)较强拮抗能力的W-4、W-10、N-14三个菌株。经鉴定W-4、W-10分别属于放线菌中黄色节杆菌(Arthrobacter flavescens)和石灰壤诺卡氏菌(Nocardia calcarea),N-14属于细菌中的乳酸乳杆菌(Lactobacillus lactis)。通过正交试验对上述3个菌株混合发酵条件进行优化,确定在温度35℃、时间36h、pH7.5、装液量60ml/250ml时为最适发酵条件。在此条件下3个菌株混合发酵液纤维素酶活力仍然很高。同时混合发酵液对青霉、曲霉、毛霉、木霉、根霉的拮抗能力分别为单菌株发酵液的1.79倍、1.36倍、1.29倍、1.04倍、1.07倍。 相似文献
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To investigate the species of cellulase-producing Bacillus in yak rumen,10 samples of rumen content were aseptically collected from 10 adult Maiwa yaks to isolate the heat-resistant Bacillus by water bath at 80 ℃ for 20 min.The cellulase-producing strains were screened using the CMC-Na medium and Congo red staining.The 16S rRNA gene sequence of those cellulose-producing strains were amplified and sequenced.The results showed that 64 strains were isolated from the 10 samples.Total 23 strains were identified as cellulase-producing bacillus,including 16 strains of Bacillus cereus,7 strains of Bacillus thuringiensis.Furthermore,phylogenetic analysis showed that the 16 Bacillus cereus strains were clustered into two branches:One isolate was clustered into a branch alone,the other 15 isolates were clustered into a branch which clustered into 5 small branches,showing that there was certain genetic diversity in the isolates of Bacillus cereus.And all 7 Bacillus thuringiensis strains were clustered into a branch.Hence,the results layed the foundation of investigating the species of cellulase-producing Bacillus in yak rumen and developing probiotics special for yak. 相似文献
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XIANG Li-jun WANG Bo-chu DUAN Chuan-ren LIU Liu WANG Qing-hongnistry of Education College of Bioengineering Chongqing University Chongqing Chin 《保鲜与加工》2004,(10):71-74
The paper researches on the degradation of LAS (Linear Alkyl benzene Sulphonate) by combining AS1.860 immobilized with low intensity ultrasonic irradiation. The paper also discusses the influence of pH, rotary velocity, LAS concentration and the condition of low intensity ultrasonic irradiation on the degradation of LAS, the degradation rate of LAS is the main index of our experiment, the results of orthogonal test shows that low ultrasonic irradiation can increase the metabolizing of microorganism cells and facilitate the biodegradation of immobilized cells to LAS, here we research the degradation condition of 50mg/L LAS simulation wastewater with low ultrasonic irradiation, and the results show that the influence is obvious, the optimization degradation rate is about 83%, nine point five percent higher than that of the immobilized cells without ultrasonic irradiation. 相似文献
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从蔗渣腐烂域筛选出一株高纤维素酶活力的特异青霉(P.notatum)YB-5,经紫外线和亚硝基胍诱变,获得一突变株YB-7,其生长快,产孢子多且无毒性。并研究了碳源、氮源、金属离子和表面活性剂对产酶的影响。在正交优化的固体培养基和优化培养条件下,60h时CMCase、FPA和β-葡萄糖苷酶活力分别可达29.4IU/ml、8.40IU/ml和25.1IU/ml。 相似文献