Abstract
Streptomyces, Gram-positive bacteria that are nurtured and survive in diverse environmental conditions and look like filamentous fungi. The Streptomyces are blessed with the ability to produce bioactive secondary metabolites with a wide range of biological activities, for example antibiotics, antivirals, antifungals, antitumorals, immunosuppressants, anti-hypertensives, anti-obesity and so on. Consequently, increasing antibiotic resistance urgently requires the identification of new and more effective microbial drugs. Moreover, many drugs that are currently used are produced from Streptomyces or are chemically modified. It is also observed that Streptomyces from extreme environments such as deep-sea, desert, cryo, and volcanic environments have been recognized as good sources of novel compounds which include alkaloids, angucycline, macrolide, and peptides. Moreover, technical advancements in culture conditions, fermentation, and genomic studies have increased the efficiency of the isolation of Streptomyces. Production of bioactive compounds from Streptomyces requires culture conditions optimization to enhance the production of the bioactive metabolite. The common optimization strategies follow one factor at a time approach (OFAT) and statistical approaches. Nowadays more advanced algorithm-based methods such as artificial neural network (ANN), genetic algorithm (GA), spectroscopy, and so on are also being explored. Other advanced approaches used for increasing production of bioactive compounds includes genetic engineering and metabolic engineering. The isolation of bioactive compounds is based on if the type of products is extracellular or intracellular, as well as solubility and polarity. The characterization of bioactive compounds includes approaches like physiochemical analysis by chromatographic and spectroscopic approaches. Including this, characterization of bioactivity is done by analysis of cytotoxicity, antimicrobial property, and other enzymatic activity.