药用植物内生真菌研究进展

药用植物内生真菌具有抗肿瘤、抗菌、抗病毒、抗氧化等活性,能够产生植物生长素、细胞激动素、赤霉素等促植物生长物质促进植物生长,从而使研究药用植物内生真菌成为寻找新型拮抗菌、抗肿瘤、抗氧化活性药物的重要资源。本文对药用植物内生真菌的多样性、分离鉴定、产生的次生代谢产物及其功能等做一综述。     

植物内生放线菌多样性研究进展

植物内生放线菌作为植物内生菌资源的一大类,具有丰富的多样性,其次级代谢产物也十分丰富,而且还具有各种生物学活性。通过了解植物内生放线菌资源的多样性,可以对其产生的生物活性物质进行筛选和分析,从而筛选出具有良好药理活性的物质应用于临床。从植物内生放线菌宿主植物、组织分布、种类和数量以及活性基因4个方面综述了植物内生放线菌的多样性资源,介绍植物内生放线菌新的微生物物种,总结了植物内生放线菌目前研究中存在的问题及展望。     

植物内生真菌及其活性代谢产物研究进展

植物内生真菌是一大类未被充分研究过的真菌,其物种及代谢产物均具有生物多样性,现今从植物内生真菌中得到的活性物质种类远比从土壤微生物中得到的多。对植物内生真菌的研究具有重要的生态学意义和经济学意义,在各个领域中应用前景广泛。作者主要综述了植物内生真菌及其活性物质研究的最新进展。     

药用植物内生真菌研究进展

我国药用植物种类丰富,但受植物资源生长周期长、产量低等限制,难以满足人类的需要。而其内生真菌丰富多样,生长快,易培养,且可以产生与宿主相同或相似的天然活性物。利用内生真菌发酵生产抗菌、抗肿瘤等天然活性物质,不仅有望解决市面上部分药物供不应求的现状,还能有效地保护珍稀、濒危的药用植物资源。本文概述了药用植物内生真菌宿主植物的选择、内生真菌分离及其次级代谢产物分离纯化和活性研究,并对研究中存在的问题进行了讨论,以期为药用植物内生真菌研究提供方法和思路。     

植物内生菌活性代谢产物最新研究进展

内生菌广泛存在于植物组织中,作为一种新型的微生物资源,具有丰富的物种多样性,也是发掘新型天然活性物质的重要途径之一,有些内生菌还能产生与宿主植物相同或相似的活性成分。因此从植物内生菌中挖掘抗菌尤其抗临床耐药菌、抗肿瘤等天然活性产物不仅为新药的研发提供了新的方向,还能在一定程度上解决传统的天然产物药源——药用植物生长缓慢、资源紧缺等问题。从多个角度概述了近年来国内外报道的植物内生菌次生代谢产物及其来源、生物活性等方面的主要成果和最新进展,以期为植物内生菌活性代谢产物的研究提供参考。     

基于植物内生菌及其次生代谢活性物质多样性的研究

据相关研究表明,植物内生菌属于新型微生物资源,并且种类较多,分布广泛,譬如在最近几年,科学家逐渐发现在植物内生菌中发现了紫杉醇等生物活性物质以及在一些产物中还发现了与次级代谢产物中相同的产物,因此对临床研究具有重要价值和潜在价值。对此研究的主题为:基于植物内生菌及其次生代谢活性物质多样性的研究。本为将从植物内生菌的多样性,植物内生菌次生代谢活性物质的多样性等方面进行逐一研究,现将文章综述如下。     

药用植物内生真菌的多样性及生物功能研究进展

药用植物内生真菌资源丰富,其代谢产物常具有抗肿瘤、抗氧化、抑菌等作用,能产生药用植物生长调节物质及与宿主相同或类似的次生代谢产物,从而成为近年来的研究热点。本文对药用植物内生真菌的分离鉴定、多样性、生物活性及生物学功能等方面进行综述,以期为今后筛选及利用有效的药用植物内生真菌奠定基础。     

兰科植物内生细菌物种多样性及其促生机理研究进展

内生细菌影响兰科植物菌根形成和共生关系的稳定性,在兰科植物的生活史中起着重要作用。内生细菌通过分泌植物激素、采用光合作用、生物固氮或促进矿质营养的循环以及产生铁载体、合成其他活性物质等途径来促进兰科植物生长发育。综述了兰科植物内生细菌物种多样性的研究方法及其对兰科植物的促生机理,基于兰科植物与共生微生物的密切关系,认为内生细菌间、内生细菌与兰科植物菌根真菌间的互作是揭示兰科植物与内生细菌互作机理的重要方向。     

人参内生菌的多样性及其次生代谢产物

人参是传统的名贵中药材,在医学上有很高的药用价值,同时也是宝贵的自然资源。内生菌广泛存在于健康植物组织内部,是植物微生态系统的重要组成部分,某些内生菌甚至能够产生同原植物相同或相似的活性物质。本文综述了从人参中分离得到内生菌的物种多样性,着重介绍从其内生真菌中发现并得到的次生代谢产物的丰富性并阐述了其在医药及生产生活中的应用前景。     

药用植物内生真菌资源——一个亟待开发的宝库

内生真菌与药用植物在长期的协同进化过程中形成了特殊的互惠共生关系,内生真菌在药用植物的生长、道地性、产量、质量、功效成分、抗逆性等方面都产生重要的影响;另一方面,药用植物内生真菌自身也能产生一些生理活性物质,在新药研发、药用植物栽培生产、菌肥开发、生防菌研发、土壤生态修复、工业化酶生产应用等方面都显示出巨大的开发潜力。我国药用植物资源丰富,其中更是蕴含着许多还不为人知的内生真菌类群,这一资源宝库亟待人们探索、开发。     

药用植物内生真菌研究现状及其应用前景

随着对药用植物内生真菌研究的深入,从药用植物内生真菌中寻找新的生物活性成分已成为研究热点。内生真菌对药用植物的生长及活性成分的形成都有影响,内生真菌活性成分已成为发现新颖结构化合物及新药物的潜在资源。简要综述了近年来在内生真菌的分离鉴定、发酵、次生代谢产物、与宿主的关系等方面的研究进展。     

Endophytic fungi isolated from medicinal plants: future prospects of bioactive natural products from Tabebuia/Handroanthus endophytes

Medicinal plants are a rich source of natural products used to treat many diseases; therefore, they are the basis for a new drug discovery. Plants are capable of generating different bioactive secondary metabolites, but a large amount of botanical material is often necessary to obtain small amounts of the target substance. Nowadays, many medicinal plants are becoming rather scarce. For this reason, it is important to point out the interactions between endophytic microorganisms and the host plant, because endophytes are able to produce highly diverse compounds, including those from host plants that have important biological activities. Thence, this review aims at presenting the richness in bioactive compounds of the medicinal plants from Tabebuia and Handroanthus genera, as well as important aspects about endophyte-plant interactions, with emphasis on the production of bioactive compounds by endophytic fungi, which has been isolated from various medicinal plants for such a purpose. Furthermore, bio-prospection of natural products synthesized by endophytes isolated from the aforementioned genera used in traditional medicine could be used to treat illnesses.

     

A potential antioxidant resource: Endophytic fungi from medicinal plants

Medicinal plants and their endophytes are important resources for discovery of natural products. Several previous studies have found a positive correlation between total antioxidant capacity (TAC) and total phenolic content (TPC) of many medicinal plant extracts. However, no information is available on whether such a relationship also exists in their endophytic fungal metabolites. We investigated the relationship between TAC and TPC for 292 morphologically distinct endophytic fungi isolated from 29 traditional Chinese medicinal plants. The antioxidant capacities of the endophytic fungal cultures were significantly correlated with their total phenolic contents, suggesting that phenolics were also the major antioxidant constituents of the endophytes. Some of the endophytes were found to produce metabolites possessing strong antioxidant activities. Several bioactive constituents from the fungal cultures and host plant extracts were identified. This investigation reveals that the metabolites produced by a wide diversity of endophytic fungi in culture can be a potential source of novel natural antioxidants.     

Diversity of cultivable endophytic fungi in two Rubia plants and their potential for production of anti-tumour Rubiaceae-type cyclopeptides

Rubia plants are one of the most important plant resources possessing significant commercial and medicinal values. Plant endophytes could benefit their host plants in different ways. Rubiaceae-type cyclopeptides (RAs), mainly isolated from Rubia plants, have attracted considerable attentions for their distinctive bicyclic structures and significant antitumor activities, but their contents in plants are low. The aim of this study is to investigate the diversity of endophytic fungi in Rubia plants and their potential for production of RAs. In this work, 143 endophytic fungi isolates were obtained from two Rubia plants. Phylogenetic analysis was performed based on the ITS rDNA sequences, and the isolates were classified into 29 genera. Among them, four endophytic fungal strains were found to produce anti-tumour RAs by LC-MS/MS analysis. This work successfully provides valuable knowledges of endophytic fungi microbiome in Rubia plants for agricultural and industrial applications, and exploits a new environmental-friendly resource of RAs.     

Bioactive secondary metabolites produced by microorganisms associated with plants

In the past few decades groups of scientists have focused their study on relatively new microorganisms called endophytes. By definition these microorganisms, mostly fungi and bacteria, colonise the intercellular spaces of the plant tissues. The mutual relationship between endophytic microorganisms and their host plants, taxanomy and ecology of endophytes are being studied. Some of these microorganisms produce bioactive secondary metabolites that may be involved in a host-endophyte relationship. Recently, many endophytic bioactive metabolites, known as well as new substances, possesing a wide variety of biological activities as antibiotic, antitumor, antiinflammatory, antioxidant, etc. have been identified. The microorganisms such as endophytes may be very interesting for biotechnological production of bioactive substances as medicinally important agents. Therefore the aim of this review is to briefly characterize endophytes and summarize the structuraly different bioactive secondary metabolites produced by endophytic microorganisms as well as microbial sources of these metabolites and their host plants.     

Piperine production by endophytic fungus Colletotrichum gloeosporioides isolated from Piper nigrum

Many endophytic fungi have been reported with the biosynthetic potential to produce same or similar metabolites present in host plants. The adaptations that might have acquired by these fungi as a result of the long-term association with their host plants can be the possible basis of their biosynthetic potential. The bioactive compounds originated from endophytes are currently explored for their potential applications in pharmaceutical, agriculture and food industries. Piper nigrum, a plant of the Piperaceae is very remarkable because of the presence of the alkaloid piperine. Piperine has been reported to have broad bioactive properties ranging from antimicrobial, antidepressant, anti-inflammatory, antioxidative to anticancer activities. Interestingly, piperine also plays a vital role in increasing the bioavailability of many drugs which again is a promising property. The current study was carried out to identify piperine producing endophytic fungus from Piper nigrum L. By screening various endophytic fungi, the isolate which was identified as member of Colletotrichum gloeosporioides was found to have the ability to form piperine and was confirmed by HPLC and LCMS. Considering the broad bioactive potential of piperine, the piperine producing fungi identified in the study can expect to have much industrial potential.     

Fungal growth promotor endophytes: a pragmatic approach towards sustainable food and agriculture

Agricultural productivity suffers a heavy loss due to plant pathogens, insect pests and various abiotic stresses. Agriculture being the world’s largest economic sector, it is the need of time to find and establish the ideal strategy for sustainable agriculture and improvement in crop growth. Endophytes are microorganisms that asymptomatically grow within the plant tissues without causing any disease to the host. Endophytic fungi live in symbiotic association with plants and play an important role in plant growth promotion, higher seed yield and plants resistant to various biotic, abiotic stresses and diseases. Many are able to produce antimicrobial compounds, plant growth hormones and various agrochemical bioactive metabolites. These mycoendophytes hold enormous potential for the development of eco-friendly and economically viable agricultural products. In this review we focused on the endophytic fungi recovered from different medicinal plants, their active principles involved in plant growth enhancement and the applications of fungal endophytes in agriculture. Moreover, we also discussed about endophytic fungi and their pragmatic approach towards sustainable food and agriculture.     

Endophytic fungi—The treasure chest of antibacterial substances

Over more than 20 years, the endophytic fungi have been explored as “biofactories” of novel bioactive substances, and they have not disappointed. Among the extracts and pure substances obtained from the culture broths or fungal biomass, some have exerted antibacterial activity ranging from moderate to powerful when tested on the bacterial strains resistant to the antibiotics currently in use. In this article we review the accumulated data on endophytic fungi isolated from plants that produce metabolites with antibacterial activity against human pathogenic bacteria.