Emerging resistance to available antibiotics is one of the biggest problems of
mankind. This problem brings a serious question to the researcher’s mind: What will be
the next promising source of novel antimicrobial compounds to overcome drug
resistance? Although many synthetic or modified chemical compounds can be used as a
new source of the drug, nature is the richest and most versatile source of new
antibiotics. Natural products and their derivatives are far more important in the
discovery of new reliable sources of pharmaceuticals. We can use natural compounds
and their derivatives to treat cancer, diabetes, and inflammatory and infectious
diseases. Other reasons why natural compounds are a good choice for new drug
discovery are their lesser side effects, skill to control the existence and development of
diseases and potential to act against resistant strains of disease-forming
microorganisms. A huge number of diversified chemical components of marine
microorganisms, provide us with a rich and versatile source of biologically active
components. But among this enormous microbial diversity, very few amounts have
been explored till now. Marine microorganisms and their metabolites are reported as an
effective and promising sources of new antibiotics or drugs that can act against various
antibiotic-resistant strains of pathogenic microorganisms. Marine bacteria, fungi, and
cyanobacteria provide numerous industrially useful bioactive components which
further possess antibacterial, antifungal and antimycobacterial activities. There are
many biotechnological methods and machines like biosensors which is used to detect
and isolate useful target components from marine microorganisms. A slight
modification in the chemical groups of marine microbes-derive bioactive compounds
generates their new derivatives, mimetic and structural analogs that can serve as a
novel drug against pathogenic microorganisms. Every structurally different molecule
acts functionally with numerous biological activities against various pathogenic
microorganisms. This criterion makes marine-derived products more valuable to us in
this contemplative time of drug resistance. In this chapter, we discuss various
metabolites of marine microorganisms (bacteria, fungi, actinomycetes, and
cyanobacteria) having promising antimicrobial properties which could act as a potential
natural source of drugs against pathogenic microorganisms.
Keywords: Antimicrobial, Antibiotic resistance, Bioactivity, Biodiscovery, Marine microbes, Marine natural products, Microbial metabolites.
