Antibacterial activity of ethanolic Spirulina platensis extract-water soluble chitosan nanoparticles

Abstract

Spirulina platensis is a microalga containing bioactive compound as antibacterial activity. The antibacterial compound from Spirulina can be used to treat bacterial infections on the skin such as acne. However, enhancement penetration of bioactive compounds through the skin was needed. The objective of this study was to determine bioactive compounds from Spirulina, synthesize Spirulina extract-water soluble chitosan nanoparticles using the ionic gelation method, and measure the antibacterial activity of Spirulina extract and its nanoparticles. For the synthesis of the nanoparticles, differences of Spirulina extract concentrations were used, including 3.25, 7.5, and 15 mg/mL. The yield of ethanolic Spirulina extract was 13.87±4.16% with the bioactive components of saponins, tannins, steroids, and phenols. The Spirulina extract-loaded chitosan nanoparticles were successfully fabricated with a nano-range size and narrow polydispersity. The amount of loading of Spirulina extract has affected the size and dispersion of nanoparticles. The antibacterial activity of nanoparticles showed higher than pure Spirulina extract only through Staphylococcus aureus and Pseudomonas aeruginosa, classified as moderate inhibition zones (5-10 mm). These suggested that nanoencapsulation could increase extract uptake on bacteria cells. The ethanolic Spirulina extract-chitosan nanoparticles have a potency for antibacterial agents on cosmeceutical products.