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Title:	Determining the prebiotic potential of gum Arabic from Acacia Senegal and Acacia Seyal using human gut microbiota
Authors:	Hamad Mohamad Salah Hamad Ahallil (P85851)
Supervisor:	Mohamad Yousf Maskat, Prof. Dr.
Keywords:	Probiotics Prebiotics Universiti Kebangsaan Malaysia -- Dissertations Dissertations, Academic -- Malaysia
Issue Date:	8-Sep-2019
Description:	Gum Arabic extruded from different Acacia trees with different functionality. Prebiotic activity is one of the most important functional which modulate the gut microbiota and hence the gut barrier functionality which led to reduction of body weight. Among the factors that made us more prone to obesity is aberrant metabolic activity or a compositional alteration of the gut microbiota. This study was carried out to test the potential of gum arabic as a prebiotic through in vitro digestion and fermentation by lean and obese microbiota. The first objective of this study was to extract and characterize the water soluble polysaccharide from Acacia senegal and Acacia seyal and determine the bile acid binding capacity and acidic digestibility as potential prebiotic. The second aim was to investigate the effect of the extracted polysaccharide from both Acacia gum on the composition and activity of human colonic microbiota from lean and obese healthy donors using an in vitro model of pH-controlled batch culture system. The third objective was to investigate the utilization and selectivity of polysaccharide from Acacia gum by Lactobacillus spp. in order to determine the synbiotic potential of the different probiotic and prebiotic combinations. The fourth objective was to degrade the polysaccharide from Acacia gum and study its utilization and selectivity by Lactobacillus spp. Water soluble polysaccharide from both Acacia gums showed significant bile acid binding capacity and non-digestibility by in vitro gastric digestion. Substrate fermentation was assessed by measuring the production of lactic acid and short-chain fatty acids (SCFA), lactate and by studying the composition of the bacterial communities over time. There was no significant difference on the growth of microbiota observed between the two different groups of microbiota from lean and obese. Compositionally, bacteria belonging to Lactobacillus and Bifidobacterium genera were found to be significantly and highly stimulated by both polysaccharides in the lean and obese microbiota. The results also showed that SCFAs from lean and obese microbiotas were different and depended on the fermentable substrate. The selectivity of polysaccharide from Acacia gum by Lactobacillus spp. showed significant difference among strains. Results showed that all the substrates including inulin were only able to be utilized Lactobacillus plantarum ATCC 8014 and Lactobacillus reuteri RC-14 but not by Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus fermentum and Lactobacillus rhamnosus GR-1. The use of the polysaccharide from Acacia senengal and Acacia seyal as carbon source affected the pattern of metabolite's production, when compared with cultures carried out without substrate, particularly in the case of Lactobacillus plantarum ATCC 8014 and Lactobacillus reuteri RC-14. The treated water soluble polysaccharide by TFA showed signifacntly higher growth and production of lactic acid and SCFAs than untreated water soluble polysaccharide. After restructuring the water soluble polysaccharide from Acacia gum the substrates become more favorable to be utilized by Lactobacillus spp. which made them perfect match for synbiotic combination. In conclusion, gum Arabic showed great prebiotic and synbiotic potential and contributes to the understanding of the role of diet and the microbiota in tackling obesity. This study also indicates limited synbiotic potential of the various probiotic/prebiotic combinations.,Certification of Masters/Doctoral Thesis is not available,Ph.D.
Pages:	228
Call Number:	QP144.F85A373 2019 tesis
Publisher:	UKM, Bangi
Appears in Collections:	Faculty of Science and Technology / Fakulti Sains dan Teknologi

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