Thermal treatment enhances the α‐glucosidase inhibitory activity of bitter melon (Momordica charantia) by increasing the free form of phenolic compounds and the contents of Maillard reaction products

Abstract

Inhibition of α‐glucosidase can slow carbohydrate metabolism, which is known as an effective strategy for diabetes treatment. The aim of this study is to evaluate the effect of thermal treatment (50, 60, and 70℃) for 15 days on the α‐glucosidase inhibitory activity of bitter melon. The results show that the bitter melon heated at 70℃ for 12 days had the best α‐glucosidase inhibitory effect. However, the amount of free polyphenols, 5‐hydroxymethyl‐2‐furfural (5‐HMF), and the browning degree of bitter melon generally increased with the time (15 days) and temperature of the thermal treatment, which is positively related to their antioxidant and α‐glucosidase inhibitory activities. In conclusion, aged bitter melon shows great α‐glucosidase inhibitory activity, which may be related to the increased free form of the involved phenolic compounds and Maillard reaction products. This suggests that thermal processing may be a good way to enhance the application of bitter melon for diabetes treatment. Practical Application The thermal processing of bitter melon provides an application for diabetes treatment. This study demonstrated that heat‐treated bitter melon can lower the blood glucose level; therefore, it can be used as a potential anti‐hyperglycemic and functional food.

Accumulation of Antioxidative Phenolics and Carotenoids Using Thermal Processing in Different Stages of Momordica charantia Fruit

“…In particular, its fruit contains health-beneficial bioactive compounds such as charantin and it is particularly attractive for use in food and pharmaceuticals. In addition, it contains plenty of vitamin C, phenolic acids, and carotenoids, which have been considered antioxidants in food ingredients [ 6 ].…”

“…Furthermore, hot-air drying is one of the most commonly employed heat treatments that alters not only the physical properties (such as hardness) but also the chemical properties (such as polyphenol decomposition) of food materials. Heat treatment increases taste preferences by promoting nonenzymatic reactions in food or inducing a change in flavor components [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 ]. Heat treatment can cause an increase in phenolic compounds and antioxidant activity in various fruit crops such as citrus, persimmon peel, and eggplant fruit [ 10 , 14 , 15 ].…”

A Novel Method for Quality Evaluation of Gardeniae fructus Praeparatus during Heat Processing Based on Sensory Characteristics and Chemical Compositions

“…Thus, the content of 5-HMF continued to grow during the heat processing of GFP. In addition, 5-HMF played a role in browning [ 20 ], and this work found the intuitive phenomena associated with it. 5-HMF increased and L* value decreased successively in deeper processed products, indicating that the 5-HMF might be related to a color change from bright to dark.…”

Upregulated synthesis and production of bioactive compounds in Lotus arabicus L. by in vitro feeding with dried powder of date palm seeds

“…For instance, HMF is the most abundant compound with a maximum peak area. HMF was reported to have crucial biological roles as an antioxidant, combating oxidative injury [ 32 – 34 ]. Like other fruits and vegetables, dates are known to produce HMF and other furan derivatives, probably from sugar dehydration [ 35 ].…”