Chapter 21 - Endophytic Fungi as a New Source of Antirheumatoid Metabolites

Abstract

Natural products (NP) are produced by living organisms and are usually secondary metabolites that are produced as a defense mechanism against predators or to aid the organism adapting to its environment. Natural products have been evolving for a very long time through natural selection. Therefore, they possess optimized biologically active metabolites that have delivered a great variety of structures for drug discovery. The first records of traditional medicine systems are from Egypt (2900 BCE), where about 1000 plant-derived medicines are described. Egyptian pharmaceutical records that date from 1500 BCE document more than 700 drugs in various formulas such as pills, snuffs, poultices, and infusions. Endophytic fungi are microfungi that internally infect living plant tissues without causing any visible manifestation of disease and live in mutualistic association with plants for at least a part of their life cycle. However, the discovery of fungal endophytes inside these plants with a capacity to produce the same compounds shifted the focus of new drug sources from plants to fungi. Bioactive natural products from these fungi are attracting considerable attention from natural product chemists and biologists alike, which is clearly depicted by the steady increase of publications devoted to this topic during recent years. Plant endophytic fungi are an important and novel resource of natural bioactive compounds with their potential applications in agriculture, medicine, and food. This chapter will highlight the antiinflammatory metabolites produced by some taxa of endophytic mycobiota isolated from some medicinal plants and their probable inhibitory effects against an adjuvant-induced arthritis (AIA) rat model and compared with the effects of methotrexate (MTX) as a standard disease-modifying antirheumatoid drug.