Bioactivity and prebiotic properties of raffinose oligosaccharides derived from different chickpeas for alternative functional food application

Currently, raffinose oligosaccharides (RFOs) derived from chickpeas are interesting to utilize as a prebiotic source. This research aimed to determine the optimal condition for RFOs extraction from two chickpea types (Kabuli and Desi) and evaluated their antioxidant, prebiotic, anti-food borne pathogen, and synbiotic properties. The results showed that RFOs could be extracted from both types of chickpeas using ethanol and hot water extraction. Kabuli chickpea showed the highest oligosaccharides content of 6.84 ± 0.52 mg/mL using 50% ethanol at 1:5 (w/v) for 60 min. HPAEC-PAD result confirmed that chickpea-RFOs were composed of raffinose, stachyose, and verbascose. Moreover, the antioxidant activity results described that chickpea-RFOs had high total phenolic compound content and high percentages of radical scavenging activities, especially chickpea-ethanol RFOs. Prebiotic properties result indicated that Desi chickpea-RFOs extracted from ethanol could promote lactic acid bacteria (LAB) growth, especially Lactobacillus casei (87.04 ± 3.50%) was able to promote the growth of LAB greater than galactooligosaccharides commercial prebiotic. Furthermore, antimicrobial growth of pathogen results confirmed that Kabuli chickpea-RFOs derived from hot water extraction had the highest inhibition of Bacillus cereus growth (37.59 ± 1.72%). The survival rate under gastrointestinal conditions, especially L. plantarum supplemented with Desi chickpea-RFOs derived from ethanol extraction in alpha-amylase conditions (259.36 ± 4.50%). The efficiency of probiotics on HTC 116 cells adhesion indicated that L. acidophilus supplemented with Kabuli chickpea-RFOs derived from hot water extraction could improve probiotics adhesion by about 46.13 ± 5.14%. Therefore, chickpea-RFOs have a high potential synbiotic substance that can be applied as a functional food for human.