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对从土壤中筛选获得的纺锤芽孢杆菌CGMCC1347生产异丁香酚单加氧酶的发酵条件进行了单因素考察及正交实验优化,确定了最适的发酵摇瓶培养基组成和培养条件.在发酵培养基组成为尿素1 g/L,玉米浆55 g/L,K2HPO4 2g/L,MgSO4·7H2O 1 g/L,初始pH 7.5,发酵温度37℃,摇床转速180 r/min的条件下培养16h获得的细胞,能转化2%的异丁香酚生成2.49 g/L香兰素,异丁香酚单加氧酶酶活达3.79 U/L. 相似文献
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木质素降解物是影响木质纤维素水解液乙醇发酵效率的主要原因之一。为探明木质素降解物对酿酒酵母的毒性,通过酿酒酵母(Saccharomyces cerevisiae)CGMCC 2.1429的液体培养,测定木质素制剂及酚类化合物(香草醛、紫丁香醇和对羟基苯甲醛)对细胞的毒性,同时分析酚类化合物的联合作用类型,最后以果糖-1,6-二磷酸(FDP)为指标来分析木质素制剂及酚类化合物酵母细胞膜通透性的变化。结果表明:木质素制剂、紫丁香醇、对羟基苯甲醛和香草醛的半致死质量浓度分别为10.96、5.37、6.17和7.08 g/L。随着各酚类化合物浓度和种类的增加,它们对细胞的毒性随之增加,呈正协同作用。在培养液中,FDP浓度随各酚类化合物浓度的增加呈线性增加,当各酚类化合物的质量浓度从1.58 g/L增加到10.00 g/L时,FDP质量浓度从49.7 mg/L增加到134.4 mg/L。木质素降解物对酿酒酵母的毒性作用与细胞膜通透性的改变密切相关。 相似文献
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微生物转化方法生产香草酸与香草醛的初步研究 总被引:7,自引:2,他引:5
从实验室保藏的菌种中筛选到一株黑曲霉(Aspergillus niger)SW-33,能够将1g/L的阿魏酸底物转化为0.23g/L的香草酸,相应的摩尔转化率为29.35%;流加四次底物阿魏酸后,产物浓度达到1.11g/L,相应的摩尔转化率为44.9%。为了提高产物浓度,对培养基和发酵条件进行优化,使得该菌株能够将1g/l的阿魏酸底物转化为0.46g/L的香草酸,相应的摩尔转化率为57.81%。提取得到的香草酸,经HPLC测定,纯度为85.9%;提取收率为75.2%。用含香草酸的转化液,或者用提取的结晶香草酸,加入朱红密孔菌(Prcnporus cinnabarnus)SW-0203发酵培养液,可得到转化产物香草醛。 相似文献
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黑曲霉CGMCC0774和朱红密孔菌CGMCC1115两步转化阿魏酸制备生物香兰素 总被引:5,自引:0,他引:5
在25 L发酵罐中黑曲霉Aspergillus niger CGMCC0774转化阿魏酸可生成香草酸2.24 g/L,摩尔转化率64.6%;朱红密孔菌Pycnoporus cinnabarinus CGMCC1115转化提取的香草酸可生成香草醛1.45 g/L,摩尔转化率为79.9%。将两步微生物转化有机串联,即用黑曲霉转化液加预先培养的朱红密孔菌Pycnoporus cinnabarinus CGMCC1115菌丝体继续转化,可产香草醛1.06 g/L,对原料阿魏酸的摩尔转化率34.0%。用米糠提取的天然阿魏酸做原料,两步串联微生物转化制备的生物香兰素经13C同位素的分析,符合生物香草素的等同要求。 相似文献
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Profiles of SARS-CoV-2 RNA and Antibodies in Inpatients with COVID-19 not Related with Clinical Manifestation: A Single Centre Study 下载免费PDF全文
Zhao Li Gao Ruqin Lu Roujian Wang Huijuan Deng Yao Niu Peihua Jiang Fachun Huang Baoying Liang Jiwei Jia Jing Zhang Feng Wang Wenling Wu Guizhen Tan Wenjie 《中国病毒学》2021,36(5):1088-1092
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RICHARD E. NORRIS 《Botanical journal of the Linnean Society. Linnean Society of London》1991,106(1):1-40
Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera. 相似文献
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JOAN VALUÈS MONTSERRAT TORRELL NÚRIA GARCIA JACAS 《Botanical journal of the Linnean Society. Linnean Society of London》2001,137(4):399-407
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted. 相似文献
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Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme
responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare
the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show
that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by
distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of
demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least
one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of
the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable
potent antiproliferative synthetic drugs. 相似文献
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正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases 相似文献
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