The Effects of Thai Black Garlic Consumption on Gut Microbiota in Thai Adults with Abdominal Obesity: A Randomized Controlled Trial

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Nuengrutai Krutkabgaew
Iyarit Thaipisuttikul
Kanokwan Manoonphol
Chadamas Promkum
Pornpoj Pramyothin
Wanjan Deekum
Chaniphun Butryee


Currently, the study of gut microbiota populations plays an important role in determining a link to obesity. Garlic has the properties of a prebiotic. A previous study has shown that S-allylcysteine (SAC) can change the gut microbiota's composition in hypertension individuals. The objective was to investigate the effect of Thai black garlic (BG) at the amount of 0.98 and 1.95 mg SAC/day on gut microbiota in abdominal obesity subjects (n=64). It is a 12-week randomized control trial. All participants were divided into 3 groups. Each participant was given a BG capsule containing 0.98 mg SAC/day (n=21), 1.95 mg SAC/day (n=19), or a placebo capsule (n = 24). Fecal samples were taken from 64 abdominal obesity participants. Fecal samples were collected at 3 time points (0, 6, and 12 weeks) for DNA extractions. The quantification of 16S rRNA gene fragments was then analyzed using the QIIME 2 software package. The results showed a significant increase in Latilactobacillus (FDR=0.0268) abundance. In line with this, Limosilactobacillus, Bifidobacterium, Christensenella, and Oscillospira tended to increase in the 0.98 mg SAC group. In the 1.95 mgSAC group at 12 weeks, Latilactobacillus, Oxalobacter, and Paludicola tended to increase. On the contrary, Ruminococcus torques group in the high-dose BG group at 6 and 12 weeks and Eggerthella in the high-dose group at 12 weeks tended to decrease when compared with the baseline. We can conclude that the intake of BG is associated with a change in the gut microbiota composition in abdominal obesity subjects.

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Krutkabgaew, N., Thaipisuttikul, I. ., Manoonphol, K. ., Promkum, C. ., Pramyothin, P. ., Deekum, W. ., & Butryee, C. . (2023). The Effects of Thai Black Garlic Consumption on Gut Microbiota in Thai Adults with Abdominal Obesity: A Randomized Controlled Trial. Thai Journal of Toxicology, 38(2), 80–101. Retrieved from
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