Thailand has vast areas of tropical forests with many indigenous plants, but limited information is available on their phytochemical profile and in vitro inhibitions of enzymatic and nonenzymatic reactions. This study investigated phenolic profiles using liquid chromatography–electrospray ionization tandem mass spectrometry (LC–ESI-MS/MS), antioxidant activities, and in vitro inhibitory activities of 10 indigenous plants on key enzymes related to obesity (lipase), diabetes (α-amylase and α-glucosidase), and Alzheimer’s disease (cholinesterases and β-secretase). The nonenzymatic anti-glycation reaction was also investigated. The 10 indigenous plants were Albizia lebbeck (L.) Benth, Alpinia malaccensis (Burm.) Roscoe, Careya arborea Roxb., Diplazium esculentum (Retz.) Swartz, Kaempferia roscoeana Wall., Millettia brandisiana Kurz., Momordica charantia, Phyllanthus emblica L., Zingiber cassumunar Roxb, and Zingiber citriodorum J. Mood & T. Theleide. Preparations were made by either freeze-drying or oven-drying processes. Results suggested that the drying processes had a minor impact on in vitro inhibitions of enzymatic and nonenzymatic reactions (<4-fold difference). P. emblica was the most potent antioxidant provider with high anti-glycation activity (>80% inhibition using the extract concentration of ≤6 mg/mL), while D. esculentum effectively inhibited β-secretase activity (>80% inhibition using the extract concentration of 10 mg/mL). C. arborea exhibited the highest inhibitory activities against lipase (47–51% inhibition using the extract concentration of 1 mg/mL) and cholinesterases (>60% inhibition using the extract concentration of 2 mg/mL), while Mi. brandisiana dominantly provided α-amylase and α-glucosidase inhibitors (>80% inhibition using the extract concentration of ≤2 mg/mL). Information obtained from this research may support usage of the oven-drying method due to its lower cost and easier preparation step for these studied plant species and plant parts. Furthermore, the information on in vitro inhibitions of enzymatic and nonenzymatic reactions could be used as fundamental knowledge for further investigations into other biological activities such as cell culture or in vivo experiments of these health-beneficial plants.

Fermented tea (Cha-miang in Thai) is a local product made by traditional food preservation processes in Northern Thailand that involve steaming fresh tea leaves followed by fermenting in the dark. Information on changes in nutritive values, bioactive compounds, antioxidant activities, and health properties that occur during the steaming and fermenting processes of tea leaves is, however, limited. Changes in nutritive values, phenolics, antioxidant activities, and in vitro health properties through inhibition of key enzymes that control obesity (lipase), diabetes (α-amylase and α-glucosidase), hypertension (angiotensin-converting enzyme (ACE)), and Alzheimer’s disease (cholinesterases (ChEs) and β-secretase (BACE-1)) of fermented tea were compared to the corresponding fresh and steamed tea leaves. Results showed that energy, carbohydrate, and vitamin B1 increased after steaming, while most nutrients including protein, dietary fiber, vitamins (B2, B3, and C), and minerals (Na, K, Ca, Mg, Fe, and Zn) decreased after the steaming process. After fermentation, energy, fat, sodium, potassium, and iron contents increased, while calcium and vitamins (B1, B2, B3, and C) decreased compared to steamed tea leaves. However, the contents of vitamin B1 and iron were insignificantly different between fresh and fermented tea leaves. Five flavonoids (quercetin, kaempferol, cyanidin, myricetin, and apigenin) and three phenolic acids (gallic acid, caffeic acid, and p-coumaric acid) were identified in the tea samples. Total phenolic content (TPC) and antioxidant activities increased significantly after steaming and fermentation, suggesting structural changes in bioactive compounds during these processes. Steamed tea exhibited high inhibition against lipase, α-amylase, and α-glucosidase, while fermented tea possessed high anti-ChE and anti-ACE activities. Fresh tea exhibited high BACE-1 inhibitory activity. Results suggest that tea preparations (steaming and fermentation) play a significant role in the amounts of nutrients and bioactive compounds, which, in turn, affect the in vitro health properties. Knowledge gained from this research will support future investigations on in vivo health properties of fermented tea, as well as promote future food development of fermented tea as a healthy food.

Legumes and pulses are nutrient-dense foods providing a good source of protein, complex carbohydrates, fiber, vitamins, minerals, and bioactive compounds. To breed a new lineage of beans with specific nutritional and health beneficial purposes, more information on original lineage beans must be obtained. However, data concerning the nutritive compositions, total phenolic contents (TPCs), and health benefits regarding the antioxidant potentials of some original lineage beans in Thailand remain scarce, causing difficulty in decisional selection to breed a new lineage. Thus, this study aimed to examine the nutritional values (proximate compositions, vitamins, and minerals), TPCs, and antioxidant activities of ten original lineage bean cultivars in Glycine, Phaseolus, and Vigna genera from Genebank, Department of Agriculture (DOA), Thailand. The results indicated that beans in the Glycine genus potentially provided higher energy, protein, fat, and calcium contents than other genera, while the Phaseolus genus tended to provide higher carbohydrate and dietary fiber. Specifically, lima bean cultivar ‘38’ exhibited high vitamin B1, and red kidney bean cultivar ‘112’ exhibited high potassium content. Beans in the Vigna genus exhibited high TPCs and antioxidant activities. However, their nutritional compositions were markedly varied. The results of this work could support bean consumption as a feasible alternative diet and be used as a reference for future bean breeding (within the same genera) of a new lineage with particular nutritional requirements and health potentials.

The present study was aimed to investigate the impacts of brown rice (BR) and retrograded brown rice (R-BR) consumption on colonic health and gut microbiota in dextran sulfate sodium (DSS) induced colitis mice. Thirty two female C57Bl/6Mlac mice were fed with modified AIN 93G diets by replacing cornstarch in the original composition with white rice (WR), BR and R-BR powder. The mice were divided into 4 groups and fed with the following experimental diets for 4 weeks: (1) negative control (WR: diet with WR), (2) positive control (DSS_WR: DSS and diet with WR), (3) DSS_BR: DSS and diet with BR, and (4) DSS_R-BR: DSS and diet with R-BR. BR and R-BR had a greater content of fat, dietary fiber, GABA, γ-oryzanol, γ-tocotrienol, ferulic acid and p-coumaric acid than WR (p < 0.05). No significant difference in the level of these bioactive compounds was noted between BR and R-BR. Nevertheless, R-BR had a 1.8 fold resistant starch (RS) content of BR (p < 0.05). The DSS_BR and DSS_R-BR groups showed a lower ratio of colonic weight to length, and a lower content of iNOS, COX-2, MPO, IL-6 and INF-γ in colonic homogenates than the DSS_WR group. However, the DSS treated mice fed with the R-BR diet had significantly milder histopathological inflammatory injury and lower colonic iNOS expression than the DSS_BR and DSS_WR groups. The percentage of mesenteric regulatory T cells significantly increased in the DSS_R-BR group compared to that in the DSS_WR group. The DSS treated mice fed with the R-BR diet showed a significant increase in cecal bacterial diversity and abundance of genera Prevotella, Ruminococcus, Dorea, Coprococcus and Dehalobacterium but a significant decrease in pathogenic bacteria including Bacteroides and Enterococcus compared to the DSS_WR group. Thus, the present data indicate that BR and R-BR ameliorate colonic inflammation in experimental colitis induced by DSS in mice by suppressing inflammatory mediators and modulating regulatory T cell responses as well as bacterial diversity in the cecum.