The In-vitro Antibacterial Effect of Colored Rice Crude Extracts against Staphylococcus aureus Associated with Skin and Soft-Tissue Infection

Abstract

Due to increases in the resistance of bacteria to the existing antimicrobial agents, plants are being used as alternative sources for the development of safe, effective, and inexpensive new agents to treat and prevent bacterial infections. Recent studies have shown that rice (Oryza sativa L.), an important source of nutrients, consumed by most of the world's population, can suppress some bacterial infections. There are many varieties of rice, e.g. white, brown, black, and red; however, the relationship between rice color and antibacterial properties remains unclear. In the present study, we investigated the antibacterial activity of colored-rice crude extracts from four different types of colored rice (Hom Nil, Neaw Dum, Mun Poo, and Sang Yod) against common bacteria causing skin and soft-tissue infections, such as Staphylococcus aureus, Streptococcus pyogenes, Enterococcus spp., Pseudomonas aeruginosa, and Escherichia coli. The results showed that all colored-rice crude extracts had antibacterial effects against S. aureus; and more notably, crude extracts of differently colored rice restricted diverse antibacterial activities. To our knowledge, this is the first report that provides a basic understanding of the antibacterial properties of colored rice against skin and wound pathogens. An understanding of these properties would be invaluable in the development of alternative, natural, and safe methods of controlling bacterial infections.

Measurements of Antibacterial Activity of Seed Crude Extracts in Cultivated Rice and Wild Oryza Species

“…The antibacterial activity exhibited by rice seeds is not only derived from the husks but brown rice is also known to possess antimicrobial activity (Gianinetti et al 2018 ; Pumirat and Luplertlop 2013 ). Therefore, we attempted to detect the antibacterial activity of brown rice by MTS assay using 107 cultivated rice varieties (106 core collection varieties + T65).…”

Antifungal activity of protein hydrolysates from Thai Phatthalung Sangyod rice (Oryza sativa L.) seeds

“…Due to high content of the major antioxidants, such as phenolic compounds and anthocyanin, most Sangyod rice studies have focused on its antioxidant activity. Its antibacterial activity is also known [34]. Only one study by Suesattayawong et al [22] reports that Sangyod rice seed has antifungal activity against the S. oryzae, a plant pathogen.…”

Anti-Inflammatory Activities of Constituents in Sang Yod Rice Extracts, γ-Oryzanol, Vitamins E, B1, B2 and B3, Using Inhibitory Effects on Nitric Oxide (NO) Production in Lipopolysaccharide (LPS) Activated RAW 264.7 Murine Macrophage Cells

“…There is only one in vitro report of antibacterial activities of pigmented-rice crude extracts from four different types of rice [20]. Recent in vivo studies in animal models has demonstrated the positive effects of black rice bran against chemically-induced inflammation, indicating that pigmented rice bran may contain anti-inflammatory and anti-allergic constituents [19,21,22].…”