共查询到20条相似文献，搜索用时 203 毫秒
1.
2.
对海南粗榧(Cephalotaxus hainanensis Li.)内生真菌F127发酵液化学组分进行研究。用多种色谱技术对F127代谢产物进行分离纯化,以LC-MS、ESI-MS和超导核磁共振分析鉴定化合物结构,最后采用MTT法测定化合物的抗肿瘤活性。从海南粗榧内生真菌F127的发酵液中分离得到5个单体化合物,分别鉴定为oblongolide T(1)、sorbicillin(2)、邻苯二甲酸二丁酯(3)、phomopsolide B(4)、6,8-二羟基-3-甲基-3,4-二氢异香豆素(5),且化合物1、4、5对肿瘤细胞K562、NB4、HL-60、Hep G-2和Lovo表现出不同抑制活性。化合物4对5株肿瘤细胞均表现出抑制活性,对K562、NB4、HL-60抑制效果显著,IC50值分别为3.35、0.014和0.16μg/m L,对Hep G-2和Lo Vo只有温和抑制作用;化合物1对K562、NB4、HL-60抑制作用良好,IC50值分别为51.82、54.25和29.31μg/m L;化合物5对NB4和Hep G-2则具有一定抑制活性;化合物2和3对测试细胞株未表现出抑制活性。5个化合物均是首次从海南粗榧内生真菌中分离得到,并首次报道了化合物1、4对K562、NB4、HL-60的优良细胞毒活性,为进一步研究海南粗榧内生真菌中的活性天然产物奠定了基础。 相似文献
3.
利用活菌菌饼法和滤纸片法研究筛选64株海南粗榧内生真菌对罗非鱼源无乳链球菌的抑菌活性,并对活性菌株的代谢产物化学成分进行初步测试。菌饼试验结果显示,11株海南粗榧内生真菌对无乳链球菌具有明显抑制作用,占总菌株数的17.2％,抑菌圈在Φ(8.7±0.3～16.2±0.2)mm间。滤纸片试验结果显示,12株具有明显抑制作用,占总菌数的18.8％,抑菌圈在Φ（8.7±0.3～28.2±0.4）mm间。2种方法的最高活性菌株不一致,但最高活性菌株（B30、F52）和同时显示较高活性的菌株（B14、B30、B32、F7、F52）被测出都含有甾体及三萜类化合物。根据结果推测,对无乳链球菌有显著抑制作用的菌株可能含有甾体及三萜类物质。结果为深入研究内生真菌对罗非鱼无乳链球菌的抑制奠定基础,也为生物防治罗非鱼病害提供有益借鉴。 相似文献
4.
以化感水稻品种‘PI312777’‘6173’和‘6180’为研究对象,从水稻根、茎和叶中分离获得70株内生真菌,采用形态学观察和rDNA-ITS区序列分析,对内生真菌进行分类鉴定。进一步以化感水稻‘PI312777’分离得到的粘红酵母和塔宾曲霉为试验菌株,通过不同稀释倍数的真菌发酵液对非化感水稻进行MS半固体培养基育苗试验,研究化感水稻内生真菌发酵产物对非化感水稻萌发率、株高等形态指标及苯丙氨酸解氨酶（PAL）、过氧化氢酶（CAT）和过氧化物酶（POD）活性的影响。结果表明,从供试化感水稻品种中共分离得到17种内生真菌,经rDNA-ITS系统发育树分析鉴定为10个属,这些内生真菌主要分布在曲霉属（Aspergillus）（29.63%）、青霉属（Penicillium）（16.67%）和镰刀菌属（Fusarium）（12.96%）。不同稀释浓度塔宾曲霉发酵液对水稻幼苗生长均有促生作用,其中50倍稀释浓度处理可显著提高水稻幼苗的株高、根长及POD酶活性。粘红酵母菌发酵液5倍稀释浓度可显著提高水稻幼苗的PAL酶活性并对水稻幼苗有促生作用。稗稻共生条件下,塔宾曲霉和粘红酵母发酵稀释液对水稻均有促生效应。本研究可为化感水稻内生真菌进一步应用于水稻生产实践提供有益指导。 相似文献
5.
海洋放线菌因其所处环境特殊，在生理性状和遗传背景方面均具有独特的性质，因此海洋放线菌具有产生特殊代谢产物的巨大潜力。本研究以西沙海绵为研究对象，挖掘其具有抑菌活性的共附生放线菌资源。首先，利用平板分离法从海绵样品中分离纯化出一株活性放线菌菌株ITBB-ZK-a5，对其进行16S rRNA基因测序，结合构建的系统发育树和菌落形态特征，确定该菌株为链霉菌。其次，采用平板对峙法研究菌株ITBB-ZK-a5对植物病原真菌的抑菌广谱性和持效性。结果表明：该菌株对供试的16株病原真菌均有较好的抑菌活性，抑菌谱较广，且对峙14、30 d仍具有活性，抑菌持效性较好；为了进一步验证该菌株平板通过产生活性物质抑制病原菌生长，对菌落边缘的无菌琼脂块进行抑菌活性研究，结果表明抑菌率与菌落距离呈负相关，说明放线菌可能通过向平板中分泌活性物质以抑制病原菌的生长。该菌株连续转接5代后，仍具有较好的世代稳定性。再次，利用大米固体培养基对菌株ITBB-ZK-a5进行发酵，乙酸乙酯萃取浓缩得到提取物，通过滤纸片法对发酵粗提物进行光稳定性和热稳定性研究，结果表明，随着水浴温度升高和紫外照射时间的增加，菌株ITBB-ZK-a... 相似文献
6.
为开发油樟内生菌资源并发现潜在活性成分,本研究以春季油樟健康植株的根、茎、叶为材料,采用组织培养法分离纯化可培养内生真菌,结合ITS序列和系统发育树分析菌株多样性,筛选具有产黄酮功能菌株,设计单因素和正交试验优化产黄酮效果最佳菌株的发酵条件。结果表明：从油樟中共分离到62株可培养内生真菌,划分为3门、7纲、14目、22科、28属、54种。其中优势门为子囊菌门（Ascomycota,RF为88.71%）,优势纲为座囊菌纲（Dothideomycetes,RF为45.16%）,优势目为格孢腔菌目（Pleosporales,RF为37.10%）,优势科为格孢菌科（Pleosporineae,RF为14.52%）、亚隔孢壳科（Didymellaceae,RF为12.90%）,优势属为链格孢属（Alternaria,RF为12.90%）、附球菌属（Epicoccum,RF为11.29%）。以纲为类群单位,根组织分离的16属20种21株真菌的系统发育可分为7个类群,茎分离的13属24种30株真菌则分为2个类群,叶的8属10种11株真菌则分为3个类群。多样性指数和均匀度系数结果表明,油樟根部内生真菌种群多样性相对较丰富,群落分布相对均匀。10株内生真菌具有产黄酮功能,5株来自根部,5株来自于茎部,隶属2门3纲5目8科9属,其中YZ-29菌株产黄酮能力相对较强。YZ-29菌株最优发酵条件为初始pH 7、时间7 d、温度30℃、转速175 r/min、装液量80 mL/150 mL。综上结果显示,内生真菌在油樟不同组织数量、种群及组成上存在差异,分离得到的功能性菌株值得深入挖掘和开发利用,为开展内生真菌在油樟抗氧化成分的生物合成机制方面的研究奠定基础。 相似文献
7.
以马铃薯品种东农305的脱毒试管苗为供试材料,采用固体培养和液体培养两种方式,在试管苗繁殖培养基(M S+3%白糖+6.5 g.L-1琼脂,pH约5.8)中加入0.05%的中草药萃取液,以常规的试管苗繁殖培养基为对照,进行试管苗生长状况的比较。试验采用二因素完全随机试验设计,3次重复,接种1周后开始取样调查,每周调查1次,固体培养调查4次,液体培养调查3次。调查苗高、茎粗、茎节数、根数和根长,对所有性状进行方差分析和差异显著性测验(SSR法)。试验结果表明:在试管苗繁殖培养基中添加中草药萃取液,对试管苗的苗高、茎粗和茎节数的增加均有一定的促进作用,只是在不同培养方式下的效果存在一定差异。对试管苗根部的作用在于增加根长,而不是增加根的数量。在本试验中,固体培养方式下添加中草药萃取液的处理效果最好,成苗时试管苗的苗高达7.3 cm,茎节数达7.1个,繁殖倍数高于其它处理。 相似文献
8.
为了抑制冠突散囊菌发酵绿茶液态饮料中儿茶素的降解,本研究采用植物乳杆菌和冠突散囊菌对绿茶液态饮料进行联合发酵,试验通过响应面法优化了联合发酵绿茶液态饮料工艺,并采用高效液相色谱（HPLC）法和顶空固相微萃取串联气质联用（HS-SPME/GS-MS）法分别检测了联合发酵绿茶液态饮料中儿茶素含量和香气成分。结果表明,在干茶添加量10βg·L-1、冠突散囊菌添加量10βmL·L-1的前提下,联合发酵绿茶液态饮料的最佳工艺条件为植物乳杆菌添加量20βmL·L-1、蔗糖添加量75βg·L-1、30℃下静置发酵3βd。在此工艺下联合发酵绿茶液态饮料中总儿茶素含量为1β419.94βμg·mL-1,与冠突散囊菌发酵绿茶液态饮料（848.72βμg·mL-1）相比,显著增加（P<0.05）;且醇类化合物（30.27%）、醛类化合物（15.25%）、烃类化合物（11.35%）、酯类化合物（9.86%）和酮类化合物（9.01%）含量与未发酵绿茶液态饮料相比均显著增加（P<0.05）。 相似文献
9.
白蚁（Isoptera）的筑巢和觅食活动主要在土壤及腐烂的木材上进行,所以白蚁极易受到来自环境病原微生物的侵害。因此,白蚁需要依赖共附生微生物菌群形成防御体系,放线菌是其中一个重要的类群,且放线菌能产生具有抗菌活性的次级代谢产物。但是白蚁共附生放线菌能否对热带作物的病原真菌有抑制活性有待研究。为了挖掘在热带农业绿色健康发展中具有应用潜力的海南特色农用放线菌资源,以海南白蚁共生放线菌为研究对象,利用平板分离法从采集的健康白蚁体内分离纯化放线菌,利用平板对峙法筛选生防菌株;通过分子生物学确定其分类地位;平板对峙法研究拮抗菌株的抗菌稳定性、持效性和广谱性;滤纸片法研究抑菌物质的热稳定性。结果从海南白蚁体内分离得到1株拮抗活性较好的放线菌菌株W7,系统发育树分析结果表明该放线菌与链霉菌属（Streptomyces）亲缘关系接近。菌株W7的抗菌活性持久性强,平板接种30 d后仍对植物病原真菌具有抑菌活性,抗菌稳定性好;菌株W7抑菌谱广,对16株植物病原真菌有不同程度的抑菌活性,其中对芒果胶孢霉（Colletotrichum gloeosporioides Penz.）、香蕉炭疽霉（Colletotrichum musae）、辣椒棒孢霉（Corynespora cassiicola）、豇豆瓜果腐霉[Pythium aphanidermatum (Edson) Fitzp]抑制作用较强,对芦笋拟茎点霉（Phomopsis asparagi）、荔枝疫霉（Peronophythora litchi）抑制作用较弱;菌株W7发酵粗提物有较好的热稳定性,但是抑菌率会随着水浴温度的增高而降低。本文首次对海南白蚁共附生放线菌进行了分离鉴定,并从中筛选得到1株具有抑制多种热带作物病原真菌活性的生防菌株,为高效生防菌剂的研发提供新资源。 相似文献
10.
覆膜方式对旱作马铃薯若干生理指标的影响 总被引：1，自引：0，他引：1
采用田间小区试验和室内分析相结合的方法,研究了露地平播、平作行上覆膜、双垄全膜覆盖、起垄行上覆膜及起垄覆膜膜侧播种五种不同覆膜方式对旱作马铃薯若干生理指标的影响,旨在探讨适合内蒙古武川县旱作马铃薯栽培的覆膜方式。结果表明,四种覆膜方式均能不同程度提高旱作马铃薯叶片相对含水量、可溶性蛋白含量,并使叶片超氧化物歧化酶活性、丙二醛含量、游离脯氨酸含量处于较低水平,以维持植株正常的生长代谢,其中以起垄覆膜膜侧播种和双垄全膜覆盖两种覆膜方式的效果最好。 相似文献
11.
12.
Infrared stabilized rice bran (SRB) substitution to white wheat, wheat bran and whole grain wheat breads at the levels of 2.5, 5.0 and 10.0% was evaluated in terms of proximate composition, crumb color, dietary fiber, texture and sensory attributes. An increasing tendency was observed in crude fat and ash content of the breads. Redness (+a*), yellowness (+b*) chroma and redness (a*/b*) values were increased gradually with the addition of SRB. Crumb color was found to be darker when 10% of SRB was added to the breads. SRB inclusion did not affect the content of soluble dietary fiber while it significantly increased the insoluble and total dietary fiber contents of the breads (p < 0.05). In general, whole grain wheat bread differed from the other bread types in terms of textural behavior. Based on the overall acceptability scores, white wheat and wheat bran breads were sensory accepted up to 10% of flour replacement with rice bran, while substitution levels higher than 2.5% negatively affected the sensory scores of whole grain wheat bread. 相似文献
13.
Effect of extrusion processing on the soluble and insoluble fiber,and phytic acid contents of cereal brans 总被引：1，自引：0，他引：1
Gualberto D. G. Bergman C. J. Kazemzadeh M. Weber C. W. 《Plant foods for human nutrition (Dordrecht, Netherlands)》1997,51(3):187-198
The health benefits associated with dietary fiber have resulted in it now being used in virtually all food product categories, including many products which are manufactured using extrusion processing. The objective of the present study was to determine if extrusion processing affected phytic acid, and soluble and insoluble fiber contents. The effect of screw speeds of 50, 70, and 100% of maximum rotations per minute (% MRPM) on these components was investigated. A BI-EX Model DNDG-62/20D co-rotating intermeshing self-cleaning twin-screw extruder, manufactured by Bühlerag, CH-9240, Uzwil, Switzerland, was used to process wheat, oat and rice brans. It was found that extrusion did not affect the insoluble fiber content of wheat bran; however, a decrease in this component was observed in rice and oat brans. The effect on rice bran insoluble fiber was greatest at screw speeds of 50 and 70% MRPM. This occurred in oat bran at 50% MRPM. Soluble fiber content increased in all brans after extrusion, except ER100. For oat and rice bran soluble fibers, the greatest increase occurred at 50 and 70% MRPM, while for wheat bran this occurred at 70 and 100% MRPM. Extrusion did not affect the phytate content of the cereal brans. 相似文献
14.
Gurpreet Singh Dhillon Harinder Singh OberoiSurinder Kaur Sunil BansalSatinder Kaur Brar 《Industrial Crops and Products》2011,34(1):1160-1167
Solid-state fermentation (SSF) was performed to evaluate the potential of agricultural residues for the production of cellulase and hemicellulase using individual and mixed cultures of Aspergillus niger and Trichoderma reseei. The maximum filter paper (FP) cellulase activity of 13.57 IU/gram dry substrate (gds), 22.89 IU/gds and 24.17 IU/gds and β-glucosidase activities of 21.69 IU/gds, 13.58 IU/gds and 24.54 IU/gds were obtained with wheat bran medium at 96 h incubation period with A. niger, T. reseei and mixed-cultures of A. niger and T. reseei, respectively. Mixed-culture SSF using rice straw supplemented with wheat bran in the ratio 3:2 resulted in higher FP cellulase, β-glucosidase, endoglucanase (CMCase) and xylanase activities, compared to the activities obtained using mono-cultures. Similarly, higher FP cellulase, β-glucosidase, CMCase and xylanase activities of 35.8 IU/gds (96 h), 33.71 IU/gds (96 h), 131.34 IU/gds (120 h) and 3106.34 IU/gds (120 h) were achieved in the tray fermentation using rice straw with wheat bran in the ratio of 3:2. Results of present investigation showed that higher cellulase activity and an optimal combination of cellulase and β-glucosidase can be achieved through mixed-culture SSF in trays. The approach of utilizing negative cost agricultural wastes through tray fermentation for cellulase and hemicellulase production is expected to serve the objectives of: (a) management of wastes which would otherwise cause environmental pollution problems; (b) production of hydrolytic enzymes at low cost and; (c) simple technique requiring no sophisticated instruments with practical applications. 相似文献
15.
木薯渣固态发酵植酸酶的条件研究 总被引：5，自引：0，他引：5
木薯渣粗蛋白及无机盐含量较低,与麸皮、米糠混合或同时添加无机氮源及无机盐,可作为发酵培养基合成植酸酶。高浓度的磷抑制植酸酶的合成。最佳发酵条件为：木薯渣为唯一碳原,添加 ２％ ＮＨ４ＮＯ３, ０．０１％ Ｋ２ＨＰＯ４, ０．０５％ ＭｇＳＯ４·７Ｈ２Ｏ, ０．０５％ ＫＣＩ, ０．０１％ ＦｅＳ－Ｏ４· ７Ｈ２Ｏ, ０．９％ ＳＤＳ,培养基水分含量 ６０％～６５％, １０ｇ木薯渣／２５０ ｍＬ三角瓶,接种量为２ｍＬ菌悬液（２．８×１０个孢子／ｍＬ）,自然 ｐＨ值,培养温度 ２８～３１℃,第８ｄ达产酶高峰,高峰期产酶量为 ６７３０ Ｕ／ｇ干曲。 相似文献
16.
Mallasy LO El Tinay AH Ahmed AR 《Plant foods for human nutrition (Dordrecht, Netherlands)》2002,57(1):63-71
Addition of wheat bran to sorghum flour (Dabar cultivar) at two extraction rates 72% and 80% resulted in lowering reducing sugars. The percent decreasewas 75.6% compared with the control at the end of fermentation period. There was a highly significant (p 0.05) increase in crude fiber content as a result of addition of wheat bran. The increase was from 0.8 to 5.2 and from 0.5 to 5.3% for the 80% S/WB and 72% S/WB blends, respectively. Sorghum bread containing wheat bran was lower in reducing sugars and showed a significant increase (p 0.05) in starch content. Sorghum bread containing wheat bran resulted in a lower in vitro protein and starch digestibilities. 相似文献
17.
Functional suitability of commercially milled rice bran in India for use in different food products 总被引：4，自引：0，他引：4
K. S. Sekhon S. S. Dhillon Narpinder Singh Baljeet Singh 《Plant foods for human nutrition (Dordrecht, Netherlands)》1997,50(2):127-140
The effect of blending of commercially available full fat and defatted rice brans in India from modern multistage rice mills
with parboiling/stabilizing facilities in different food products in comparison to those obtained from laboratory milling
of rice is reported. Bread volume and cookie spread decreased but muffin volume increased with the addition of different types
of bran to wheat flour, however, the cookie spread factor was not affected by addition of full fat rice bran. The yields of
the extrudate were increased by the blending of full fat rice bran but were decreased by the addition of defatted rice bran.
Rice brans could be added to different food products to the extent of 5–10%. However, the full fat rice bran could not be
used for production of extruded snack food. 相似文献
18.
Wheat bran is the main by-product during wheat flour processing. Although wheat bran is rich in the bioactive compounds and antioxidant capacity, it is not widely utilized in its natural state. To improve the antioxidant and nutritional properties of wheat bran, a dominant strain, Enterococcus faecalis M2, was screened from lactic acid bacteria (LAB) isolated from various foods. Following solid state fermentation, the soluble dietary fiber content of wheat bran nearly quadrupled compared to the raw material. Total proportion of phenols, flavonoids, alkylresorcinols, along with the antioxidant capacity and free radical scavenging rate were significantly improved, particularly the ferulic acid content increased by 5.5 times. Additionally, the free amino acid content increased with degradation of wheat bran protein, whereas the level of anti-nutrient phytic acid decreased. The results of this study could provide an effective method for biological modification of wheat bran, which further enhance the health benefit and utilization of bran. 相似文献
19.
小麦麸皮营养与质量安全品质分析 总被引：1，自引：0，他引：1
为促进我国小麦麸皮资源的加工转化,收集了我国9个小麦主产省12家大型面粉加工企业的商品小麦麸皮样品,对蛋白质、淀粉、膳食纤维、戊聚糖、脂肪、灰分等主要营养成分以及重金属、农药残留、真菌毒素等安全危害因素进行了分析与比较。结果表明,不同来源的小麦麸皮在营养组成上存在一定差异,其中以总淀粉含量差异最大(CV:35.31%),粗蛋白含量差异最小(CV:5.16%);麸皮蛋白的氨基酸组成中,以蛋氨酸含量差异最为显著(CV:20.06%)。质量安全指标中,重金属含量均未超标,农药残留未检出;真菌毒素,仅河北邯郸一家麸皮样品中的脱氧雪腐镰刀菌烯醇(DON)含量超出限量范围。对比所选取12个样品的品质表现,收集于河北邢台、山东滨州和北京的样品,戊聚糖、蛋白质含量较高,总淀粉含量较低,卫生状况良好,可用于小麦麸皮的深加工与综合利用。 相似文献
20.
《Industrial Crops and Products》2000,11(1):1-5
The lignocellulosic biomass (especially agricultural wastes) is known to be an excellent carbon source for microbial enzyme production. In this paper, the cellulase production from lignocellulosic materials under solid state fermentation (SSF) was investigated. The effects of fermentation conditions, such as moisture content, initial pH, temperature, and composition of mixed substrate (wheat straw and wheat bran) on endoglucanase production by Aspergillus niger 38 were studied. With a moisture content of 74% a pH range of 4.5–5.5 on mixed substrate containing wheat straw:wheat bran of 9:1, 14.80 international units (UI) endoglucanase activity/ml were obtained in 96 h. 相似文献