Chemical Properties, Total Phenolic Content, Antioxidant Activity, and Inhibition of Domestic Animal Related Bacteria using Dried Somsa (Citrus aurantium var. aurantium) Peel Powder

Abstract

This study was performed to evaluate the chemical properties, total phenolic content, antioxidant activity, and inhibition of domestic animal related bacteria of dried Somsa (Citrus aurantium var. aurantium) peel powder (DSP). The pH and total soluble solid of DSP diluted with distilled water at 1:10 ratio (w/v) were 3.91±0.11 and 3.57±0.12 ◦Brix, respectively. The total titratable acidity, total phenolic content and antioxidant activity of diluted DSP were 0.14±0.04%,1,677.34±21.23 mg GAE/100g and 4,604.54±49 mg/100 g, respectively. Inhibition of pathogenic bacteria (Escherichia coli CIP 76.24, Staphylococcus aureus CIP 75.25, Salmonella Typhimurium CIP 58.58, Listeria innocua CIP 80.11^T) and lactic acid bacteria (Lactobacillus plantarum TISTR 926, Pediococcus acidilactici V202, Enterococcus faecium C707, Enterococcus faecalis CF1GI 15) of DSP extract was conducted by agar well diffusion assay. Our results found that E. coli CIP 76.24 was inhibited by DSP extract, whereas other tested bacteria were not. This study indicated that DSP has the potentiality to be applied as a feed additive due to its contain phenolic content, antioxidant activity, and inhibition efficiency of the growth of E. coli.