植物内生真菌抗肿瘤活性成分研究进展

从植物内生真菌中获得了一系列具有多样性结构的抗肿瘤活性化合物. 对植物内生真菌所产生的萜类、生物碱、黄酮、甾体、酯类化合物的结构和对肿瘤细胞的抑制作用、抑制效果, 以及这些内生真菌的寄主植物等几方面进行了综述, 并且简要讨论了这些内生真菌与其寄主植物之间的化学生态学关系.     

植物内生真菌抗植物病原真菌活性物质的研究

植物内生真菌的代谢产物中存在一系列具有多样性结构的抗植物病原真菌的活性化合物(AFC)。本文以化合物结构为线索,对植物内生真菌所产生的具有抗植物病原真菌活性的生物碱、肽类、萜类、甾体、醌、有机酸、酯类等化合物的结构,对病原菌的抑制效果及其寄主植物等几方面进行了总结。从3个方面简单介绍了农用抗生素的作用机制,即作用于真菌细胞壁、细胞膜,以及抑制真菌蛋白质的生物合成。最后对AFC作为新型农用抗生素来源的前景进行了展望,其具有作为先导化合物,开发高效、低毒、无公害农用抗生素的巨大潜力。     

无花果内生真菌FL25发酵产物中两个吲哚生物碱的研究

植物内生真菌具有可以产生结构新颖和活性很强化合物的功能[1].为此,我们对药用植物无花果的内生真菌进行了研究,从其根、茎、叶中分离得到了64株内生真菌.     

具有生物活性的植物内生真菌次生代谢产物

植物内生真菌是指那些在其生活史中的某一段时期生活在植物组织内,对植物组织没有引起明显病害症状的真菌.植物内生真菌几乎在所有植物中存在,它们种类繁多,分布广泛,在长期的自然选择下与寄主植物形成和谐的共生关系,使其产生的次生代谢产物十分丰富,这对农业、医药行业等的发展都具有着巨大的潜在价值.本文对近年来从65种植物中分离获...     

一株曲霉属印楝植物内生真菌的代谢产物研究

内生真菌(Endophytic fungi)是指其在生活史的某一段时期生活在植物组织内,对植物组织没有引起明显病害症状的真菌[1]。内生真菌具有丰富的多样性,是一大类尚未被开发的资源。近年来的研究表明,它们能产生结构多样的活性代谢产物,已成为国内外的研究热点之一[2]。印楝(Azadirac     

植物内生真菌生物碱活性成分的研究进展

大量的生物碱从植物内生真菌中分离了出来, 并表现出良好的生物活性. 对植物内生真菌所产生的生物碱, 按照酰胺类、有机胺类、吡咯类、喹啉和异喹啉类、吲哚类、吡啶类、喹唑啉类进行了综述, 并且介绍了这些生物碱的生物活性.     

4-羟基-2-吡啶酮类天然生物碱的研究进展

4-羟基-2-吡啶酮类生物碱是从植物和昆虫等内生真菌发酵液中提取分离得到的一类新型天然生物碱, 具有抗真菌、抗菌和抗肿瘤等多种生物活性. 对近年来4-羟基-2-吡啶酮类天然生物碱的分离、结构确证和全合成等进行了总结和概述, 重点介绍了Ilicilolin H, Tenellin和Sambutaxin等的全合成.     

模拟宿主防御肽的尼龙3抗菌聚合物结构设计、合成及活性研究

微生物感染一直是人类健康的严峻挑战,传统抗生素几乎不可避免地使微生物产生耐药性,因此亟待开发既对耐药细菌、真菌有活性,又不易使微生物产生耐药性的新型抗菌剂.宿主防御肽(host defense peptide,HDP)几乎存在于各种生命形式中并表现出广谱抗菌活性和不易使微生物产生耐药性的特点,近年来作为对抗微生物耐药性的新途径被广泛研究.为解决HDP自身稳定性差(容易被蛋白酶水解)的缺点,多个研究组相继开展HDP模拟物的研究,希望在改善抗菌剂稳定性的同时保持抗菌活性.尼龙3聚合物(β-多肽)是模拟HDP的一类代表性抗菌聚合物.尼龙3聚合物通常由一个亲水性/正电荷亚基和一个疏水性亚基通过不同比例组合来模拟HDP的2个关键性结构特点:正电荷和两亲性结构.通过优化端基基团和聚合物长度、变化亚基的化学结构、探索优化的亲水性/正电荷与疏水性亚基组合以及调节亚基在聚合物中的比例,发现了对多个耐药菌菌株具有高活性和高选择性的尼龙3聚合物.尼龙3对细菌营养细胞和稳定的孢子都显示了活性,同时尼龙3也对游离真菌细胞和真菌生物膜都表现出选择性抗菌活性.这些发现提示了尼龙3对抗微生物耐药性的潜力以及尼龙3作为新型抗菌剂的可能应用.     

三七内生真菌Talaromyces Purpureogenus中2个Drimane倍半萜绝对构型的鉴定

采用经典柱色谱法从三七内生真菌Talaromyces purpureogenus中分离得到2个化合物(1和2),经核磁共振波谱和质谱确认其结构均为Drimane倍半萜.通过量子化学计算比较电子圆二色谱(ECD)、旋光(OR)与实验值的方法鉴定了化合物1和2的绝对构型.生物活性测试结果显示,化合物1对大肠杆菌(E.coli)具有一定的抗菌活性(MIC=25μmol/L).     

用HPLC-MS-MS快速分析和鉴定三尖杉植物内生真菌发酵液中的Brefeldin A

采用HPLC-MS-MS联用技术．分析了C56和C65两株具有抗肿瘤活性的三尖杉植物内生真菌发酵液抽提物,首次报道了这两株真菌都能产生Brefelkin A(BFA)。采用ESI-MS总离子流跟踪分析HPLC的洗脱液,并用低能量的CID-MS-MS(碰撞诱导裂解方式)进一步确定目标离子峰为BFA分子离子峰．这为植物内生真菌发酵液中的有效成分的早期鉴别奠定了基础。     

Alkaloids produced by endophytic fungi: a review

In recent years, a number of alkaloids have been discovered from endophytic fungi in plants, which exhibited excellent biological properties such as antimicrobial, insecticidal, cytotoxic, and anticancer activities. This review mainly deals with the research progress on endophytic fungi for producing bioactive alkaloids such as quinoline and isoquinoline, amines and amides, indole derivatives, pyridines, and quinazolines. The biological activities and action mechanisms of these alkaloids from endophytic fungi are also introduced. Furthermore, the relationships between alkaloid-producing endophytes and their host plants, as well as their potential applications in the future are discussed.     

Chemical ecology of endophytic fungi: origins of secondary metabolites

Endophytes constitute a remarkably multifarious group of microorganisms ubiquitous in plants and maintain an imperceptible association with their hosts for at least a part of their life cycle. Their enormous biological diversity coupled with their capability to biosynthesize bioactive secondary metabolites has provided the impetus for a number of investigations on endophytes. Here, we highlight the possible current and future strategies of understanding the chemical communication of endophytic fungi with other endophytes (fungi and bacteria) and with their host plants, which might not only allow the discovery and sustainable production of desirable natural products but also other mostly overlooked bioactive secondary metabolites.     

Endophytic Fungi Produce Gibberellins and Indoleacetic Acid and Promotes Host-Plant Growth during Stress

We isolated and examined two endophytic fungi for their potential to secrete phytohormones viz. gibberellins (GAs) and indoleacetic acid (IAA) and mitigate abiotic stresses like salinity and drought. The endophytic fungi Phoma glomerata LWL2 and Penicillium sp. LWL3 significantly promoted the shoot and allied growth attributes of GAs-deficient dwarf mutant Waito-C and Dongjin-beyo rice. Analysis of the pure cultures of these endophytic fungi showed biologically active GAs (GA₁, GA₃, GA₄ and GA₇) in various quantities. The cultures of P. glomerata and Penicillium sp. also contained IAA. The culture application and endophytic-association with host-cucumber plants significantly increased the plant biomass and related growth parameters under sodium chloride and polyethylene glycol induced salinity and drought stress as compared to control plants. The endophytic symbiosis resulted in significantly higher assimilation of essential nutrients like potassium, calcium and magnesium as compared to control plants during salinity stress. Endophytic-association reduced the sodium toxicity and promoted the host-benefit ratio in cucumber plants as compared to non-inoculated control plants. The symbiotic-association mitigated stress by compromising the activities of reduced glutathione, catalase, peroxidase and polyphenol oxidase. Under stress conditions, the endophyte-infection significantly modulated stress through down-regulated abscisic acid, altered jasmonic acid, and elevated salicylic acid contents as compared to control. In conclusion, the two endophytes significantly reprogrammed the growth of host plants during stress conditions.     

Withanolide production by fungal endophyte isolated from Withania somnifera

Withanolides, the secondary metabolite from Withania species is used in Ayurvedic medicine and now proved to have potential use in treating cardiovascular, Alzheimer’s disease, etc. Its production in plants varies between genotypes with very low yield. For improved industrial commercialisation, there is a need to increase its production. Endophytic fungi are symbiotically associated with plants and can synthesise the same bioactive compounds and natural products as their host plant. There are no reports available on withanolide-producing (endophytic) fungi. The present study identified an endophytic fungus (Taleromyces pinophilus) from leaves of Withania somnifera which produces withanolides in the medium. The structure of withanolide was confirmed by ¹H NMR, LC-MS analyses and quantified by HPLC analysis. The fungus produces high amount of withanolide when compared to leaf and root of W. somnifera. The fungus can be exploited to produce the withanolide to meet its demand.     

Host defense peptides and lipopeptides: modes of action and potential candidates for the treatment of bacterial and fungal infections

Endogenous peptide antibiotics (termed also host-defense or antimicrobial peptides) are known as evolutionarily old components of innate immunity. They were found initially in invertebrates, but later on also in vertebrates, including humans. This secondary, chemical immune system provides organisms with a repertoire of small peptides that act against invasion (for both offensive and defensive purposes) by occasional and obligate pathogens. Each antimicrobial peptide has a broad but not identical spectrum of antimicrobial activity, predominantly against bacteria, providing the host maximum coverage against a rather broad spectrum of microbial organisms. Many of these peptides interact with the target cell membranes and increase their permeability, which results in cell lysis. A second important family includes lipopeptides. They are produced in bacteria and fungi during cultivation on various carbon sources, and possess a strong antifungal activity. Unfortunately, native lipopeptides are non-cell selective and therefore extremely toxic to mammalian cells. Whereas extensive studies have emerged on the requirements for a peptide to be antibacterial, very little is known concerning the parameters that contribute to antifungal activity. This review summarizes recent studies aimed to understand how antimicrobial peptides and lipopeptides select their target cell. This includes a new group of lipopeptides highly potent against pathogenic fungi and yeast. They are composed of inert cationic peptides conjugated to aliphatic acids with different lengths. Deep understanding of the molecular mechanisms underlying the differential cells specificity of these families of host defense molecule is required to meet the challenges imposed by the life-threatening infections.     

A novel sesquiterpene alcohol from Fimetariella rabenhorstii, an endophytic fungus of Aquilaria sinensis

A novel sesquiterpene alcohol, named frabenol (1), was isolated from liquid cultures of Fimetariella rabenhorstii A20, an endophytic fungus of the agarwood-forming plant Aquilaria sinensis (Lour.) Gilg. The structure of the new compound was elucidated on the basis of spectroscopic methods. The finding of a sesquiterpenoid compound in F. rabenhorstii A20 implied that endophytic fungi of agarwood-producing plants could also contribute to the generation of fragrant chemicals during the agarwood formation processes.     

Terpenoids from endophytic fungi

This work reviews the production of terpenoids by endophytic fungi and their biological activities, in period of 2006 to 2010. Sixty five sesquiterpenes, 45 diterpenes, five meroterpenes and 12 other terpenes, amounting to 127 terpenoids were isolated from endophytic fungi.     

Protease Produced by Endophytic Fungi: A Systematic Review

The purpose of this systematic review was to identify the available literature of production, purification, and characterization of proteases by endophytic fungi. There are few complete studies that entirely exhibit the production, characterization, and purification of proteases from endophytic fungi. This study followed the PRISMA, and the search was conducted on five databases: PubMed, PMC, Science Direct, Scopus Articles, and Web of Science up until 18 May 2021, with no time or language restrictions. The methodology of the selected studies was evaluated using GRADE. Protease production, optimization, purification, and characterization were the main evaluated outcomes. Of the 5540 initially gathered studies, 15 met the inclusion criteria after a two-step selection process. Only two studies optimized the protease production using statistical design and two reported enzyme purification and characterization. The genus Penicillium and Aspergillus were the most cited among the eleven different genera of endophytic fungi evaluated in the selected articles. Six studies proved the ability of some endophytic fungi to produce fibrinolytic proteases, demonstrating that endophytic fungi can be exploited for the further production of agents used in thrombolytic therapy. However, further characterization and physicochemical studies are required to evaluate the real potential of endophytic fungi as sources of industrial enzymes.