Rhodomyrtus tomentosa Fruits in Two Ripening Stages: Chemical Compositions, Antioxidant Capacity and Digestive Enzymes Inhibitory Activity

Abstract

Rhodomyrtus tomentosa fruit (RTF) has been known as a food source with multiple health-care components. In this work, nutrition characteristics, free and bound phenolic profiles, antioxidant properties in vitro and digestive enzymes inhibitory activities of un-fully mature RTF (UM-RTF) and fully mature RTF (FM-RTF) were evaluated for the first time. Results verified that high levels of energy, ascorbic acid, organic acids and total phenolics were observed in FM-RTF. Moreover, FM-RTF had significant higher total phenolic content (TPC), but significantly lower total flavonoid content (TFC) than UM-RTF. In addition, twenty phenolic compounds in RTF were identified by high performance liquid chromatography–electrospray ionization–quadrupole time-of-flight tandem mass spectrometry (HPLC-ESI-qTOF-MS/MS) method. Quantitative analysis results indicated that gallic acid, ellagic acid and astragalin were the predominant free phenolics, while gallic acid and syringetin-3-O-glucoside were dominant in bound phenolic fractions. In contrast, higher contents of phenolics were observed in FM-RTF. The results also confirmed that FM-RTF exhibited higher antioxidant activities and digestive enzymes inhibitory activities than UM-RTF. Strong inhibitory ability on α-glucosidase was found in RTF, while bound phenolics showed a stronger α-amylase inhibitory effect than free phenolics. Moreover, the interaction between the main phenolic compounds and α-glucosidase/α-amylase was preliminary explored by molecular docking analysis. The results provided valuable data about the chemical compositions and biological potential of R. tomentosa fruits in both maturation stages studied.

Genomic analysis based on chromosome-level genome assembly reveals Myrtaceae evolution and terpene biosynthesis of rose myrtle

“…At present, many volatile compounds have been detected in rose myrtle [ 13 ], especially the leaves are enriched with (+)-α-pinene and β-caryophyllene [ 14 , 15 ]. These simple and polymeric terpenoids function as photoprotectants, antifeedants, or physical barriers, playing vital roles in plant growth, development, and environmental interaction [ 16 – 18 ]. Commercially used essential oils, including myrtle oil, lavender oil and tea tree oil, are a mixture of volatile terpenes [ 19 ], with a growing amount of importance in industrial applications [ 20 , 21 ].…”

Deep Eutectic Solvents-Based Ultrasound-Assisted Extraction of Antioxidants from Kudingcha (llex kudingcha C.J. Tseng): Process Optimization and Comparison with Other Methods

“…Meanwhile, phenolics are key secondary metabolites in Kudingcha and have extensive biological activities, which causes Kuding tea to have good medicinal values and clinical application [8,9]. Many researchers have tried to exploit natural antioxidants instead of synthetic compounds [10,11]. On this basis, it is urgent to develop an efficient extraction method to obtain natural antioxidants from Kudingcha.…”