Nanoformulation and Application of Phytochemicals as Antimicrobial Agents

Abstract

Plants are a major source of medicine from which most drug compounds emanate. Therapeutic phytochemicals have been used as model candidates for the synthesis of chemical drugs and pharmaceuticals. Recent increase in scientific knowledge of the chemical composition and activity of plant compounds has resulted in potential opportunities to cure a wide variety of diseases. The antimicrobial property of most phytochemicals contributes significantly to its therapeutic efficiency through the inhibition of microbial growth. Plants contain compounds such as phenols, flavonoids, quinones, tannins, terpenoids, essential oils, and alkaloids, which act as antimicrobial agents individually or in combinations. Conventional chemical-based antimicrobial agents are mostly toxic to humans and the environment, nontarget specific, and often cause side effects. Phytochemicals as antimicrobials with chemomolecular formulation can overcome all these drawbacks with increased bioavailability.As plants contain a variety of phytochemicals, efficient extraction, isolation, and purification processes are required to obtain the desired antimicrobial phytochemical in order to specifically characterize its potential efficacy. Extraction methods such as solvent extraction, supercritical fluid extraction, microwave-assisted extraction, solid phase extraction, and chromatographic techniques have been used to obtain phytochemicals from a wide range of plant sources. Modifications to these extraction methods have been performed by several researchers to increase extract yield and reduce extraction time and energy consumption. Though phytochemicals have successfully demonstrated antimicrobial properties against various microbes, including bacteria, fungi, algae, and virus, the performance efficiency is still lower than chemical antimicrobials. In order to make phytochemicals more effective against microbes, improved formulation is required to enhance stability, bioavailability, and efficiency. Research advances in nanoformulation using biocompatible materials create a significant opportunity to enhance the performance of phytochemicals as antimicrobials. Nanoformulation of antimicrobial phytochemicals using dendrimers, polymers, micelles, liposomes, and microemulsions has been demonstrated to improve antimicrobial performance in wastewater treatment, food processing, and medical applications as antibiotics. This chapter discusses biochemical process advancements in the extraction and purification of phytochemicals with antimicrobial properties. Various nanoformulation technologies essential to enhance the antimicrobial efficacy of phytochemicals and possible applications are also discussed.