Effect of chitin on biological control activity of Bacillus spp. and Trichoderma harzianum against root rot disease in pepper (Capsicum annuum) plants     

A. Sid Ahmed  M. Ezziyyani  C. Pérez Sánchez  M.E. Candela 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(6):633-637

Two bacterial isolates and one strain of Trichoderma harzianum were tested alone and in combination with chitin for efficacy in control of root rot disease caused by Phytophthora capsici and Rhizoctonia solani in pepper plants under greenhouse conditions. These bacteria (Bacillus subtilis HS93 and B. licheniformis LS674) were isolated from repeatedly washed roots of pepper plants. In in vitro assays, HS93, LS674 and T. harzianum were antagonistic against P. capsici and R. solani and produced high levels of chitinase. Seed treatment and root drenching with bacterial suspensions of HS93 with 0.5% chitin was more effective against Phytophthora and Rhizoctonia root rot than addition of the organisms without chitin. LS674 and T. harzianum reduced Rhizoctonia but not Phytophthora root rot. In two greenhouse tests, seed treatment and root drenching with HS93 amended with chitin enhanced its biocontrol activity against P. capsici but not on R. solani. The effects of LS674 and T. harzianum against R. solani were significantly enhanced when they were used as suspensions with 0.5% chitin for root drenching, but this had no effect on P. capsici. In both greenhouse experiments, the use of 0.5% chitin alone for root drenching reduced Rhizoctonia root rot. Reduction of root rot disease was accompanied by increased yield. These results show that the antagonistic activity of HS93, LS674 and T. harzianum may be stimulated by chitin resulting in significant improvements in their effectiveness against pathogens.  相似文献   

甲壳素对连作平邑甜茶生长、光合及抗氧化酶的影响   总被引：2，自引：0，他引：2  

王艳芳  潘凤兵  付风云  相立  张先富  陈学森  沈向  毛志泉 《园艺学报》2015,42(1):10-18

以苹果连作土盆栽的平邑甜茶幼苗为试材,探讨了0、0.5、1.0和2.5 g·kg-1不同施入量的甲壳素对其光合速率、活性氧含量及抗氧化酶活性的影响。结果表明,1.0 g·kg-1的甲壳素处理能显著促进幼苗株高、地径,干样质量和根冠比的增加,根冠比为对照的1.51倍;明显提高了幼苗叶片光合色素含量、净光合速率和蒸腾速率,其中光合速率为对照的1.30倍;同时提高了幼苗叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性,分别为对照的1.10倍、1.85倍、1.77倍和1.43倍;减少了叶片丙二醛(MDA)、过氧化氢(H2O2)和超氧阴离子的积累,分别为对照的73%、62%和34%,降低了脯氨酸(Pro)和可溶性糖含量。当甲壳素施用量为2.5 g·kg-1时则显著抑制平邑甜茶幼苗生长,降低幼苗叶片光合速率和抗氧化酶活性,并使超氧阴离子和脯氨酸含量明显上升。因此,适宜用量的甲壳素能减轻苹果的连作障碍。  相似文献   

Marine-Derived Chitosan Nanoparticles Improved the Intestinal Histo-Morphometrical Features in Association with the Health and Immune Response of Grey Mullet (Liza ramada)     

Mahmoud A.O. Dawood  Mahmoud S. Gewaily  Ali A. Soliman  Mustafa Shukry  Asem A. Amer  Elsayed M. Younis  Abdel-Wahab A. Abdel-Warith  Hien Van Doan  Adel H. Saad  Mohamed Aboubakr  Hany M.R. Abdel-Latif  Sabreen E. Fadl 《Marine drugs》2020,18(12)

Marine-derived substances are known for their beneficial influences on aquatic animals’ performances and are recommended to improve intestinal health, immunity, and anti-oxidative status. The present study investigates the role of chitosan nanoparticles on the intestinal histo-morphometrical features in association with the health and immune response of Grey Mullet (Liza ramada). Chitosan nanoparticles are included in the diets at 0, 0.5, 1, and 2 g/kg and introduced to fish in a successive feeding trial for eight weeks. The final body weight (FBW), weight gain (WG), and specific growth rate (SGR) parameters are significantly increased while feed conversion ratio (FCR) decreases by chitosan nanoparticles compared to the control (p < 0.05). The morphometric analysis of the intestines reveals a significant improvement in villus height, villus width, and the number of goblet cells in chitosan-treated groups in a dose-dependent manner. Additionally, there is a positive correlation between the thickness of the enterocyte brush border and the chitosan dose, referring to an increasing absorptive activity. Histologically, the intestinal wall of Grey Mullet consists of four layers; mucosa, sub-mucosa, tunica muscularis (muscular layers), and serosa. The histological examination of the L. ramada intestine shows a normal histo-morphology. The epithelial layer of intestinal mucosa is thrown into elongated finger-like projections, the intestinal villi. The values of hemoglobin, hematocrit, red blood cells (RBCs), total protein (TP), albumin, and globulin are significantly increased in fish fed 1, and 2 g/kg of chitosan nanoparticles compared to fish fed 0 and 0.5 g/kg (p < 0.05). The highest levels of TP and albumin are observed in fish fed 1 g/kg diet (p < 0.05). The lysozyme activity and phagocytic index are significantly enhanced by feeding chitosan nanoparticles at 0.5, 1, and 2 g/kg, whereas the phagocytic activity is improved in fish fed 1 and 2 g/kg (p < 0.05). The highest lysozyme activity and phagocytic index are observed in fish fed 1 g/kg. SOD is significantly activated by feeding chitosan nanoparticles at 1 g/kg. Simultaneously, glutathione peroxidase (GPx) and catalase (CAT) activities also are enhanced by feeding chitosan at 1 and 2 g/kg, compared to fish fed 0 and 0.5 g/kg (p < 0.05). The highest GPx and CAT activities are observed in fish fed 1 g/kg (p < 0.05). Conversely, the malondialdehyde (MDA) levels are decreased by feeding chitosan at 1 and 2 g/kg, with the lowest being in fish fed 1 g/kg (p < 0.05). To summarize, the results elucidate that L. ramada fed dietary chitosan nanoparticles have a marked growth rate, immune response, and anti-oxidative response. These improvements are attributed to the potential role of chitosan nanoparticles in enhancing intestinal histo-morphometry and intestinal health. These results soundly support the possibility of using chitosan nanoparticles at 1–2 g/kg as a feasible functional supplement for aquatic animals.  相似文献   

甲壳素、壳聚糖对家禽生产性能及脂肪代谢的影响   总被引：1，自引：0，他引：1  

王润莲  孔祥浩 《中国畜牧杂志》2006,42(5):57-59

本文就甲壳素、壳聚糖的发现、来源、制备、结构和性质;甲壳素、壳聚糖对家禽生产性能及脂肪代谢的影响;甲壳素和壳聚糖的降脂机理及今后的研究发展方向进行综述。  相似文献   

甲壳素等生物制剂对仙客来枯萎病的防治效果及生长促进作用研究     

黄建明  郑志兴  尉文彬  武玉环  曹丽霞 《中国植保导刊》2007,27(10):12-13

对比试验结果表明,甲壳素单独使用、甲壳素与放线菌混合使用、甲壳素与放线菌和枯草杆菌混合使用灌根,对仙客来枯萎病均具有明显的防治效果,仙客来成活率显著提高,其防效与常用化学农药相当。同时对仙客来的生长发育均有促进作用。处理后根的数量、根系的鲜重和干重均有显著增加,并使叶片数增多,冠径增大。此外,单独使用甲壳素还使土壤中放线菌数量明显增加。  相似文献   

用丰年虫卵壳制备甲壳素和壳聚糖     

孙文敏  李铮  李久红 《渔业现代化》2008,35(2):57-59

介绍了用丰年虫卵壳制备甲壳素及壳聚糖的方法及过程,通过傅立叶变换红外光谱仪的检测并与美国标准谱图库检索出的用蟹壳制备的壳聚糖光谱图对照,证实丰年虫卵壳制备的壳聚糖。  相似文献   

Emerging Biomedical Applications of Nano-Chitins and Nano-Chitosans Obtained via Advanced Eco-Friendly Technologies from Marine Resources     

Riccardo A. A. Muzzarelli  Mohamad El Mehtedi  Monica Mattioli-Belmonte 《Marine drugs》2014,12(11):5468-5502

The present review article is intended to direct attention to the technological advances made in the 2010–2014 quinquennium for the isolation and manufacture of nanofibrillar chitin and chitosan. Otherwise called nanocrystals or whiskers, n-chitin and n-chitosan are obtained either by mechanical chitin disassembly and fibrillation optionally assisted by sonication, or by e-spinning of solutions of polysaccharides often accompanied by poly(ethylene oxide) or poly(caprolactone). The biomedical areas where n-chitin may find applications include hemostasis and wound healing, regeneration of tissues such as joints and bones, cell culture, antimicrobial agents, and dermal protection. The biomedical applications of n-chitosan include epithelial tissue regeneration, bone and dental tissue regeneration, as well as protection against bacteria, fungi and viruses. It has been found that the nano size enhances the performances of chitins and chitosans in all cases considered, with no exceptions. Biotechnological approaches will boost the applications of the said safe, eco-friendly and benign nanomaterials not only in these fields, but also for biosensors and in targeted drug delivery areas.  相似文献   

Bioproduction of Chitooligosaccharides: Present and Perspectives     

Woo-Jin Jung  Ro-Dong Park 《Marine drugs》2014,12(11):5328-5356

Chitin and chitosan oligosaccharides (COS) have been traditionally obtained by chemical digestion with strong acids. In light of the difficulties associated with these traditional production processes, environmentally compatible and reproducible production alternatives are desirable. Unlike chemical digestion, biodegradation of chitin and chitosan by enzymes or microorganisms does not require the use of toxic chemicals or excessive amounts of wastewater. Enzyme preparations with chitinase, chitosanase, and lysozymeare primarily used to hydrolyze chitin and chitosan. Commercial preparations of cellulase, protease, lipase, and pepsin provide another opportunity for oligosaccharide production. In addition to their hydrolytic activities, the transglycosylation activity of chitinolytic enzymes might be exploited for the synthesis of desired chitin oligomers and their derivatives. Chitin deacetylase is also potentially useful for the preparation of oligosaccharides. Recently, direct production of oligosaccharides from chitin and crab shells by a combination of mechanochemical grinding and enzymatic hydrolysis has been reported. Together with these, other emerging technologies such as direct degradation of chitin from crustacean shells and microbial cell walls, enzymatic synthesis of COS from small building blocks, and protein engineering technology for chitin-related enzymes have been discussed as the most significant challenge for industrial application.  相似文献   

总状毛霉(Mucor racemosus)甲壳素脱乙酰酶全长cDNA的克隆及序列分析     

蒋霞云  邹曙明  周培根 《农业生物技术学报》2006,14(6):981-985

用保守的特异引物进行PCR扩增,结合RACE技术,分离和克隆到了总状毛霉(Mucorracemosus)甲壳素脱乙酰酶(CDA)的全长cDNA,并进行了全序列测定,提交GenBank登陆号DQ538514。研究结果表明:(1)总状毛霉CDA基因全长为1506bp,包括67bp5'非翻译区,1344bp阅读框以及95bp3'非翻译区,3'非翻译区包含Poly(A)加尾信号AATAAA。总状毛霉的CDA基因共编码448个氨基酸,在该基因中部还包含一个144氨基酸的多糖脱乙酰酶结构域,约占CDA基因全长的32%。(2)总状毛霉CDA基因与其它相近种米根霉(Rhizopusoryzae)、卷柄根霉(Rhizopuscircinans)的CDA1和CDA2、鲁氏毛霉(Mucorrouxii)、卵形孢球托霉(Gongronellabutleri)、匍枝根霉(Rhizopusstolonifer)、布拉克须霉(Phycomycesblakesleeanus)和酿酒酵母(Saccharomycescerevisiae)的CDA1和CDA2的基因序列同源性分别为:75%、58%、56%、56%、48%、39%、39%、17%和16%;相应的氨基酸序列的同源性分别为:69%、57%、59%、55%、47%、30%、32%、18%和21%。表明CDA基因在不同的真菌中有着不同的亲缘关系。(3)根据总状毛霉CDA基因的氨基酸序列构建的不同真菌的系统树,与采用经典分类法构建的系统树基本一致。(4)通过生物信息学的方法,预测该基因所编码的蛋白质三级结构,验证了该蛋白质具有甲壳素脱乙酰酶完整的功能性结构,并包含一个多糖脱乙酰酶结构域,两者具有相似的空间结构。  相似文献   

从害虫马尾松毛虫中提取甲壳素的初步研究   总被引：6，自引：1，他引：6  

刘高强  刘卫星  魏美才  周虎  吕聪 《西北林学院学报》2007,22(2):138-141

采用酸碱法对马尾松毛虫蛹中甲壳素的提取方法进行了初步研究。重点分析了N aOH不同处理条件对脱有机物质和甲壳素产率的影响,确定了从马尾松毛虫蛹中提取甲壳素的基本工艺:(1)脱矿物质:盐酸浓度为2.5%,浸泡时间为20 h,浸泡温度为30℃;(2)脱有机物质:N aOH浓度为6%,浸泡温度为75℃,浸泡时间为10 h;(3)脱色:双氧水浓度为9%,浸泡时间为2.5 h,浸泡温度为80℃。在此条件下,获得的甲壳素产品为白色粉状固体,其N含量为6.87%,灰分为1.19%,水分为8.37%。产率为29.97%。产品的N含量达到食品级甲壳素标准,灰分含量达到工业级甲壳素标准。实验有助于后续深入研究马尾松毛虫蛹中甲壳素的提取,也为今后进一步制备虫蛹壳聚糖打下了基础。  相似文献