Phenolic Profiles, Antioxidant Activities, and Neuroprotective Properties of Mulberry (Morus atropurpurea Roxb.) Fruit Extracts from Different Ripening Stages

Abstract

The present work investigated the phenolic profiles (including nonanthocyanin and anthocyanin phenolics), antioxidant activities, and neuroprotective potential of mulberry fruit (MF) (Morus atropurpurea Roxb.) grown in China at different ripening stages. High-performance liquid chromatography-tandem mass spectrometry method (HPLC-MS/MS) was used to identify and quantify the phenolic compounds. The antioxidant capacity, total phenolic content (TPC), total flavonoid content (TFC), and total monomeric anthocyanin content (TAC) were determined using spectrophotometric methods. The neuroprotective effects of MFs at different ripening stages were investigated using Aβ -treated PC12 cells as the cellular model of Alzheimer's disease. Of the 19 phenolic compounds characterized from the MF extracts, the contents of rutin and anthocyanins increased and that of chlorogenic acid decreased significantly with maturity. At the fully ripened stage, MF extracts showed the highest amounts of TPC (11.23 mg gallic acid equivalents/g fresh weight), TFC (15.1 mg rutin equivalents/g fresh weight), and TAC (1177 mg cyanidin 3-O-glucoside equivalents/100 g fresh weight). Meanwhile, antioxidant activity of MF extracts at this stage was highest according to ABTS (an IC50 value of 4.11 μg/mL) and DPPH (an IC50 value of 10.08 μg/mL) assays. Cellular assays revealed increased cell viability in cells treated with the ripe MF extracts; compared with the control groups, the ripening fruits also increased the antioxidant enzyme levels in PC12 cells. Together, these results suggest that the antioxidant activities and neuroprotective properties of ripening MFs are related to the contents and types of phenolic compounds that are present in the fruits.

Mulberry Fruit Extract Ameliorates AdipogenesisviaIncreasing AMPK Activity and Downregulating MicroRNA-21/143 in 3T3-L1 Adipocytes

“…Mulberry fruit has antioxidative properties, mainly due to the presence of polyphenols. 9 In particular, anthocyanins in mulberry fruit have been shown to inhibit the oxidation of free radicals. 10 The freeze-dried mulberry fruit powder improved antioxidant status of blood and hepatic superoxide dismutase and glutathione peroxi-dase activity in rats fed high-fat diet.…”

Nutraceutical and Medicinal Property of Mulberry Fruits: A Review on Its Pharmacological Potential

“…At present, isolation and characterization of the phytochemicals from mulberry fruits are imperative, as these fruits are consumed in many countries for dietary enhancement (10). Mulberry fruits harbor a diverse array of biological elements that have elite nutritional value and, many of them decorated with antioxidant properties due to the presence of polyphenolic groups (16).…”

Phenolic profiles and antioxidant capacities of mulberry ( Morus atropurpurea Roxb.) juices from different cultivars

“…In previous studies, Yang et al [9] investigated mulberry fruit at different stages of ripeness, and found that fully ripened mulberry fruit extracts contained the highest TPC. Here, the mulberry fruits tested were all mature, allowing meaningful comparisons of TPC levels among different mulberry cultivars.…”

“…takes only 25 to 30 d, which is relatively short compared with other fruits. [9] Mulberry fruits are increasingly popular with consumers because of their unique flavor, and nutritional and medicinal values. [10] Mulberry fruits are eaten in various forms, including fresh, or processed into jams and juices.…”

“…[23,24] The characteristics of the phenolic compounds in mulberries have been previously studied, but only in a few cultivars, including "Da10", "Taiwan 1 hao", and "Yue74". [9,25,26] There are at least 1,000 mulberry cultivars. [8] Little attention has been given to other mulberry cultivars.…”