Functional foods have been identified as whole foods and fortified, enriched, or enhanced products which have a potentially beneficial effect on health when consumed as part of a varied diet on a regular basis, at effective levels. As consumer awareness on functional food escalates, the interest towards conducting scientific studies in this field has also proportionately increased. Many of the traditional food products are known to possess bioactive components, thus qualifying as functional food. Kombucha tea is produced by fermenting sugared black tea with a mixed culture of yeast and bacteria. Kombucha tea has gained immense popularity in recent times due to many associated health benefits. The therapeutic effects of this beverage are thought to be derived from the chemical composition of this beverage, mainly the polyphenols and secondary metabolites which are produced during fermentation. However, the safety aspects of the beverage also need to be taken into account when qualifying the beverage as a functional food. Nevertheless, Kombucha tea could be easily recognized as a beverage which is able to replace the consumption of carbonated beverages due to its possession of health benefits and therapeutic properties.

Oxidative stress is the root cause of diabetic macro- and microvascular complications. Biochemical and epidemiological studies indicate that current treatments for diabetes do not reduce risks of developing complications, suggesting their inability to alleviate the levels of oxidative stress. This study in streptozotocin (STZ)-induced diabetic rats was carried out to investigate the effect of combining the antidiabetic drug, metformin, with an ethanolic extract of Scutellaria baicalensis, a plant whose root is known for its radical scavenging activity. Three groups of STZ-induced diabetic rats were given the following treatments for 30 days: (1) metformin 500 mg/kg, (2) S. baicalensis 400 mg/kg, (3) metformin 500 mg/kg + S. baicalensis extract 400 mg/kg. In addition, vehicle-treated diabetic and nondiabetic controls were used in the experiment. The rats treated with S. baicalensis and metformin + S. baicalensis had elevated hepatic activities of the antioxidant enzymes--superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) compared to the vehicle- and metformin-treated diabetic groups (p < 0.05). Plasma and hepatic lipid peroxide concentrations in the herb-treated and herb + metformin-treated groups were also significantly reduced (p < 0.05). In addition, the combined treatment caused significant elevations of plasma and pancreatic insulin levels and reductions of plasma and hepatic triglycerides (TG) and cholesterol levels. The study thus showed that S. baicalensis enhanced the antidiabetic effect of metformin in STZ-induced diabetic rats by improving the antioxidant status. It also increased pancreatic insulin content as well as improved the lipid profile in these rats.

No abstract

Kombucha fermentation is traditionally carried out by inoculating a previously grown tea fungal mat into a freshly prepared tea broth and incubating under aerobic conditions for 7–10 days. In this study, four kombucha beverages were prepared by placing the tea fungal mats in sugared Sri Lankan black tea at varying concentrations for a period of 8 weeks. The antioxidant activities, physicochemical, and qualitative properties were monitored prior to the commencement of the fermentation process, one day after the inoculation with the microorganisms and subsequently on a weekly basis. All samples displayed a statistically significant decrease (p < .05) in the antioxidant activity at the end of 8 weeks, which was indicative of the decreasing functional properties of the beverage. The physicochemical properties indicated increased acidity and turbidity, which might decrease consumer appeal of the fermented beverage. Further studies are necessary to test the accumulation of organic acids, nucleic acids, and toxicity of kombucha on human organs following the extended period of fermentation.

Overall, the edible plants were observed to display a high antioxidant potential with starch hydrolase inhibitory properties, which were beneficial in their being recognized as functional food.

Diabetes is a global pandemic which warrants urgent attention due to its rising prevalence and economic burden. Thus, many alternative therapies are being researched for antidiabetic properties, given the inefficacy of current medicinal treatments. From this perspective, Aronia melanocarpa or black chokeberry has been investigated for its therapeutic properties in many studies, especially for its ability to combat hyperglycemia-induced oxidative stress and the macrovascular complications of diabetes including cardiovascular disease. Though A. melanocarpa is native to the eastern areas of North America, it has been planted extensively in Europe and Asia as well. Several in vivo studies have displayed the antioxidant properties of A. melanocarpa berry juice and plant extract in rat models where oxidative stress markers were observed to have significant reductions. Some of the potent bioactive compounds present in the fruits and other parts of the plant were identified as (−)-epicatechin, chlorogenic acid, neochlorogenic acid, and cyanidin-3-galactoside. Overall, A. melanocarpa could be considered a good source of antioxidants which is effective in combating hyperglycemia-induced oxidative stress.

Summary Enhancement of antioxidant and starch hydrolase inhibitory properties of king coconut water when subjected to fermentation with the ‘tea fungus’ was evaluated. pH, colour, viscosity, ethanol content, antioxidant activity, total phenolic content, ferulic and p‐coumaric acid contents and starch hydrolase inhibitory activities were analysed for 7 days in fermented and unfermented king coconut water samples. The fermented sample had a statistically significant decrease (P < 0.05) in pH. Colour values indicated the fermented beverage to increase in ‘yellowness’ over time. A statistically significant increase in the total phenolic content and the antioxidant activity (P < 0.05) was observed from day 1 onwards in the fermented sample. The starch hydrolase inhibitory activities in the fermented beverage had statistically significantly increased (P < 0.05) by day 7. Overall, the study highlights an enhancement of the antioxidant and starch hydrolase inhibitory properties of king coconut water as a result of the kombucha‐based fermentation.

A B S T R A C TThe total antioxidant capacity of Pinus gerardania, or Chilgoza and the presence of antioxidant compounds which typically exist in pine nuts were quantified. Oxygen radical absorbance capacity assay, ferric reducing antioxidant power, and the 2, 2-diphenyl-1-picrylhydrazyl (DPPH•) and 2, 2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+) radical cation scavenging assays were conducted on dichloromethane, ethanol, ethyl acetate, hexane, methanol and water extracts of Chilgoza. The water and dichloromethane extracts displayed the highest antioxidant activity across all assays. Antioxidant compounds such as gallocatechin, catechin, lutein, lycopene, caretenoids and tocopherols were present in all extracts.Gallocatechin had the highest presence out of all the compounds. Its amounts present in the water and dichloromethane extracts were 64.9 and 56.9 µg per gram fresh weight (µg/g), respectively. The total carotenoid contents in the water and dichloromethane extracts were 14.72 and 14.26 µg/g, respectively, while the total tocopherol contents were 1.05 and 2.53 µg/g, respectively.