Optimization of phenolic compounds extracting conditions from Ficus racemosa L. fruit using response surface method

Optimization of aqueous extraction of antioxidants from Chrysanthemum (C. morifolium Ramat and C. indicum L.) flowers and evaluation of their protection from glycoxidation damage on human αA-crystallin

Chrysanthemum tea is commonly consumed by Chinese consumers mainly due to the Chrysanthemum flower being a potential source of antioxidants. The current study investigates the effects of extraction time and temperature on Chrysanthemum flower aqueous extract (CFAE) antioxidant capacity, including Trolox equivalent antioxidant capacity (TEAC), ferrous iron-chelating activity, and superoxide radical scavenging capacity (SRSC) using a two-factor, three-level factorial design of the response surface method (RSM). The TEAC and SRSC of CFAE are higher at higher temperatures and longer times up to a certain point, and the highest TEAC and SRSC are achieved at a 100 °C extraction temperature for 45 min. The fructose induced-αA-crystallin (Cry) glycation model system was used to evaluate the effects of the CFAE on anti-glycoxidation activities. The antioxidant ingredients obtained from CFAE significantly impede the production of advanced glycation end products from protein glycoxidation products (dityrosine, kynurenine, and N'-methylkynurenine) in the glycation process of αA-Cry and exhibit strong anti-glycating activity. The glycation inhibitory effects of CFAE are concentration-dependent. C. indicum L. exhibits greater potential for preventing cataracts compared to C. morifolium Ramat CFAE's antioxidant and anti-glycation properties suggest its potential application as a natural ingredient in the development of agents to combat glycation.

α-Glucosidase, α-amylase inhibition kinetics, in vitro gastro-intestinal digestion, and apoptosis inducing abilities of Ficus microcarpa L. f. and Ficus racemosa L. fruit polysaccharides

A rich source of nutrients, figs have a number of clinically validated benefits. This study aimed to evaluate the in vitro simulated gastrointestinal digestion, and the antidiabetic and anticancer activity of Ficus microcarpa (FMP) and F. racemosa (FRP) fruits polysaccharides. The pre-digested FMP revealed higher sugar content (721 ± 14.81 mg glucose equivalents/g sample) than FRP. After in vitro digestion, isolated fruit polysaccharides showed effective uptake with over 80% sugar loss. Free radicals and enzymatic inhibition after gastric digestion have been significantly modified, demonstrating the effective absorption of FMP and FRP through the intestine. Conversely, after the continuous digestion, the nutritional content of the isolated polysaccharides was gradually decreased compared to the pre-digested sample. At 30 µg/mL concentration of FMP and FRP was inhibited by 50% of breast cancer cells. The present study reveals the potential uptake of FMP and FRP as nutritional supplements in the future.

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Understanding the bioaccessibility, α-amylase and α-glucosidase enzyme inhibition kinetics of Allmania nodiflora (L.) R.Br. ex Wight polyphenols during in vitro simulated digestion

This study renewed focus on Allmania nodiflora, a green leafy vegetable with diverse nutritional and medicinal properties. The bioaccessibility and the impact of in vitro simulated digestion on polyphenolics were investigated and identified using LC-MS. Although in vitro digestion reduced polyphenolics, the pancreatic digested sample showed a significant bioaccessibility of 97% with better metal ion binding activity (99%). Increased α-amylase and α-glucosidase inhibition (>45%) potentials were also observed in the digested samples. The presence of compounds such as rutin, caffeic acid, catechin, saikosaponin was also identified to be responsible for the enzyme inhibition against postprandial hyperglycemia. These results indicated that the pH of the digestive buffers is responsible for the structural changes in polyphenols for assimilation in the intestine. Hence, A. nodiflora leaf could serve as a functional food having higher assimilated polyphenolics with abundant therapeutic potential, which would be indispensible for future nutraceutical product development from green leafy vegetables.

The influence of the extraction method on bioactivity of the root of Tetrastigma hemsleyanum

Tetrastigma hemsleyanum is traditionally used as a folk medicine and functional food in China. Its extracts have been confirmed to have many bioactivities. However, the effect of extracting temperature on its bioactivity has not been reported. In this research, the total flavonoids content (TFC), total polyphenol content (TPC), antiproliferative, antioxidant, and anti-inflammatory activities of ethanol extracts and water extracts (extracted at 55, 70, 85, and 100°C) were observed. The results indicated that ethanol extracts showed better antioxidant activity with DPPH EC50 of 504.1 ± 3.8 μg/ml and ABTS EC50 of 851.4 ± 3.9 μg/ml. A better antiproliferative activity on HepG2, PC12, Caco-2, and Hela cells was observed on ethanol extracts. The results of anti-inflammatory activities also indicated that all of the extracts can reduce the NO production of LPS-stimulated macrophage with dose-independent manner. In summary, the results showed that the antiproliferative, antioxidant, and anti-inflammatory activities of water extracts decreased with the increasing temperature to some extent.

Antidiabetic and Cosmeceutical Potential of Common Barbery (Berberis vulgaris L.) Root Bark Extracts Obtained by Optimization of 'Green' Ultrasound-Assisted Extraction

Berberis vulgaris is rich in berberine, an isoquinoline alkaloid, with antidiabetic activity, often used topically for skin-related problems. The aim of this work was to develop a “green” method for berberine extraction using mixtures of water with glycerol, a non-toxic, environmentally-friendly solvent. Response surface methodology based on Box–Behnken design was used to optimize the experimental conditions for ultrasound-assisted extraction of berberine and anti-radical components from B. vulgaris root bark. The independent variables were temperature (X₁), glycerol concentration (X₂), and ultrasound power (X₃), while the responses were berberine concentration and DPPH radical scavenging activity of the extracts (RSA IC₅₀). The response values of the extracts prepared at optimum conditions were (response, X₁, X₂, X₃): berberine yield (145.5 μg/mL; 80 °C, 50%, 144 W) and RSA IC₅₀ (58.88 μL/mL; 80 °C, 30%, 720 W). The observed values deviated from the predicted values by −3.45% and 6.42% for berberine and RSA IC₅₀, respectively, thus indicating the validity of the selected models. The prepared extracts demonstrated antioxidant, anti-melanogenic, and anti-inflammatory activity, as well excellent α-glucosidase and α-amylase inhibitory activity. The displayed biological properties and lack of glycerol toxicity makes the prepared extracts suitable for direct inclusion into antidiabetic and dermatologic food supplements and topical products.