Antioxidant activity, GABA (γ-aminobutyric acid) production, and potential for colonization of Lactobacillus fermentum InaCC B1295 encapsulated with cellulose microfiber hydrogel from oil palm solid waste during storage

Abstract

Lactobacillus fermentum InaCC B1295 is a probiotic bacterium that improves intestinal and immune systems, positively impacting human health. It produces various bioactive compounds, including bacteriocin, antioxidant enzymes, and gamma-aminobutyric acid (GABA), and colonizes the human gastrointestinal system. This study aimed to evaluate the antioxidant activity (IC50), GABA production, and colonization potential of L. fermentum InaCC B1295 with encapsulation by cellulose microfiber from oil palm solid waste (trunk, frond, leaf, and empty bunches) at room and refrigeration temperature with storage time 0, 14, and 28 days. The strain InaCC B1295 showed a high activity to scavenging ability against DPPH (1,1-diphenyl-2-picrylhydrazyl) for the treatment with encapsulation with oil palm empty bunches at refrigeration temperature after storage 14 days, which reached 88.56 ppm. Furthermore, L. fermentum InaCC B1295 produced GABA ranging from 0.435 mg/L to 2.215 mg/L. Lactobacillus fermentum InaCC B1295 encapsulated with oil palm leaf produced the most GABA at 0-day storage with a concentration of 2.215 mg/L and decreased during storage for all treatments. L. fermentum InaCC B1295 cells encapsulated in CMF hydrogel from empty oil palm fruit bunches had a lower autoaggregation value than free cells. The cells encapsulated with CMF hydrogel from oil palm empty bunches, on the other hand, had higher coaggregation and hydrophilicity values than the free cells (unencapsulated cells).