Prebiotic Effects of Extracts from Pineapple and Curcuma xanthorrhiza Rhizomes towards the Growth of Lacticaseibacillus paracasei

For the past few decades, plant derivatives have much been patronized in multiethnic Malaysia as traditional and complimentary medicines. Plant extracts and their phytochemical compounds have shown remarkable positive impacts on probiotics in gut. Therefore, this study was conducted to investigate the effects of several plant extracts and their phytochemical compounds on the growth of the probiotic Lacticaseibacillus paracasei (L. paracasei). Pineapple juice, pineapple waste extract, Curcuma xanthorrhiza extract, mixture of pineapple juice and Curcuma xanthorrhiza extract, inulin and mixture of inulin and bromelain were supplemented to liquid media and tested on L. paracasei at the shake flask scale for cell density, pH, postbiotic metabolites and bioactivities. Among the four extracts tested, Curcuma xanthorrhiza extract exhibited the highest cell density (1.7532) and proteolytic (12.012 U/mL), along with the lowest pH. Pineapple juice also showed a lowest pH value (5.685). The mixture extract demonstrated the highest lactic acid production (538.812% v/v), phenolics (222.494 ppm) and antioxidative capacity (IC50 2.3347). Saccharide utilization was observed for all supplemented media after an 8 hours fermentation process, exceeding 85%. The findings demonstrated that all plant extracts stimulated L. paracasei growth and exhibited prebiotic properties, suggesting their potential commercialization as new functional foods and beverages.