Abstract
The natural environment acts as the largest ‘bio-laboratory” of yeast, algae,
fungi, plants etc., which are used as an abundant source of biomolecules. These
different biomolecules play vital roles in the formation of different biogenic metals or
metalloid nanoparticles. Recently, the overburden from the different microbial diseases
has increased rapidly in different application sectors, viz., drug delivery, DNA analysis,
cancer treatment, antimicrobial agents, water treatment and biosensor and catalysts, as
a result of multipurpose work occurrence globally. The indiscriminate and arbitrary use
of antibiotics in clinical practice has spurred the emergence of potentially lifethreatening multidrug-resistant pathogens. In the quest for novel antimicrobial agents,
the current interest is to develop potent antimicrobial agents which exhibit broadspectrum bactericidal activity and possess a mechanism of action that does not readily
favor the development of resistance. The use of nanoscale materials as bactericidal
agents represents a novel paradigm in antibacterial therapeutics. Actually, eco-friendly,
sustainable modern approaches, such as green syntheses of different biogenic metals or
metalloid nanoparticles, are cost-effective and environment-friendly, and they are used
as strong antimicrobial agents. This chapter focuses on synthesizing biogenic metal or
metalloid nanoparticles with special emphasis on microbial synthesis, particularly from
yeast, bacteria, algae, fungi, plants extract, etc. Finally, a detailed description of the
biosynthesis mechanism using different green sources, along with their antimicrobial
activity and mode of action, has been presented.