Bioaccessibility and bioavailability of polyphenols from sour mangosteen (Garcinia xanthochymus) fruit

Effect of Winemaking on Phenolic Compounds and Antioxidant Activities of Msalais Wine

Msalais wine (MW) is a popular traditional wine with the cultural characteristics of a specific Chinese ethnic group. In this study, phenolic profiles and antioxidant characteristics were identified using chromatographic analysis. A total of thirty-eight compounds, including eight furans, eleven phenolic acids, fourteen flavonoids, and five others, were identified via LC-MS/QTOF. It was found that catechin is the most abundant phenolic compound in MW, followed by epicatechin, gallic acid, caffeic acid, rutin, and p-coumaric acid. Winemaking had a significant influence on the levels of phenols and antioxidant activity. Condensed juice (CJ) displayed the highest phenol and antioxidant activity levels, while the levels were significantly decreased during the fermentation process and gradually stabilized thereafter during the aging process. A correlation analysis between the polyphenols in Msalais and their antioxidant capacity was performed to determine which molecules contributed more to the antioxidant capacity in a complex mixture of polyphenols. All of the phenolic compounds, except ferulic acid, showed good correlation with DPPH, ABTS, and CUPRAC. Among them, resveratrol had the strongest antioxidant capacity, although its concentration was very low. Catechin also had a strong antioxidant capacity, which was positively correlated with its concentration. This indicates that the antioxidant activity of Msalais is related to the number, type, and structure of polyphenols.

Bioavailability of Rosehip (Rosa canina L.) Infusion Phenolics Prepared by Thermal, Pulsed Electric Field and High Pressure Processing

In this study, the in vitro bioavailability of rosehip infusion phenolics, mainly catechin, as a response to conventional and non-thermal treatments by combining gastrointestinal digestion and a Caco-2 cell culture model, was investigated. After application of thermal treatment (TT, 85 °C/10 min), high pressure (HPP, 600 MPa/5 min) or pulsed electric field (PEF, 15 kJ/kg) processing, all samples were subjected to simulated gastrointestinal digestion. Then, the amount of maximum non-toxic digest ratio was determined by the cytotoxicity sulforhodamine B (SRB) assay. Next, Caco-2 cells were exposed to 1:5 (v/v) times diluted digests in order to simulate the transepithelial transportation of catechin. Results showed that non-thermally processed samples (5.19 and 4.62% for HPP and PEF, respectively) exhibited greater transportation across the epithelial cell layer compared to than that of the TT-treated sample (3.42%). The present study highlighted that HPP and PEF, as non-thermal treatments at optimized conditions for infusions or beverages, can be utilized in order to enhance the nutritional quality of the final products.

Ethanolic extract of Pyrus pashia buch ham ex. D. Don (Kainth): A bioaccessible source of polyphenols with anti-inflammatory activity in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Pyrus pashia Buch ham ex. D. Don (Kainth) fruit from the Himalayan region is traditionally consumed by native people in the form of decoctions for various clinical conditions including inflammatory diseases. However, scientific studies on the biofunctional properties of Kainth fruits are still scarce.

AIM OF THE STUDY

The study is aimed to investigate the anti-inflammatory effects of Kainth fruit extracts using in vitro and in vivo inflammation models.

MATERIAL AND METHODS

Free, esterified and bound fractions from the Kainth ethanolic extracts were prepared for determining the anti-inflammatory effect. The levels of 5-LOX and COX-2 were determined in vitro. The protein levels of cytokines (IL-6, TNF-α & IL-10) were quantitated by ELISA method in lipopolysaccharide-stimulated RAW macrophages. Also, the anti-inflammatory potential of the Kainth fruit extracts was determined using the carrageenan-induced mice paw edema model. The bioaccessibility of Kainth fruit extracts was measured using a simulated in vitro digestion system (salivary, gastric and intestinal).

RESULTS

The Kainth fruit extracts were partially purified to yield free, esterified and bound phenolics. Free and bound phenolics of Kainth fruits inhibited 5-Lipoxygenase, Cyclooxygenase-2 activities and pro-inflammatory cytokines (Interleukin-6 and tumour necrosis factor-α) expression in vitro. Also, oral administration of these extracts to the carrageenan-injected mice showed an anti-inflammatory effect by decreasing the pro-inflammatory cytokines and reducing the cellular infiltration in paw tissues. Also, both the extracts showed better bioavailability and bioaccessibility in in vitro and in vivo studies.

CONCLUSIONS

The results indicated that free and bound phenolics from Kainth fruits that are rich in catechin, epicatechin, arbutin and chlorogenic acid exhibited anti-inflammatory effects and could potentially be used to treat inflammatory diseases.

Ameliorative Efficacy of the Cassia auriculata Root Against High-Fat-Diet + STZ-Induced Type-2 Diabetes in C57BL/6 Mice

Diabetes mellitus is a major metabolic disorder worldwide. Several herbs are being tested for the management of diabetes. Cassia auriculata is one of those herbs known for its nutritional value and health benefits. However, limited scientific evidence has been shown on the elucidation of its root bioactives as well as biological activity. This study attempted to identify and characterize phenolic compounds from the potent root extract and to evaluate its antioxidant as well as antidiabetic properties in both in vitro and in vivo models. The results revealed that the total polyphenol and flavonoid contents were highest in the methanolic extract. The methanolic extract of the C. auriculata root showed the highest antioxidant and antidiabetic activities in vitro than other extracts. These biological activities may be because the extract is rich in coumaric acid and -OH groups as revealed by high-performance liquid chromatography and Fourier-transform infrared spectroscopy analyses, respectively. Further, the antidiabetic activity of the methanolic extract was studied in a diet-induced type-2 diabetes mellitus (T2DM) C57BL/6 mouse model. A significant increase in fasting blood glucose and decreased plasma insulin levels in T2DM mice confirmed the development of the diabetic condition. In addition, the T2DM mice showed oxidative stress in the plasma as well as muscle tissue and significant alterations in the plasma biochemistry, viz., lipid profile, liver, and renal function tests. However, the administration of the ethanolic extract of the C. auriculata root (150 mg/kg body weight) to T2DM mice normalized the condition comparable to that of control mice. Thus, the extract can be used as a potent antioxidant and antidiabetic agent in pharmaceutical companies.