Polyphenols bioaccessibility and bioavailability assessment in ipecac infusion using a combined assay of simulated in vitro digestion and Caco-2 cell model

In this report, we investigated for the first time the total polyphenols content (TPC) and antioxidant activity before and after digestion of Carapichea ipecacuanha root infusion, better known as ipecac, prepared at different concentrations. An in vitro digestion system coupled to a Caco-2 cell model was applied to study the bioavailability of antioxidant compounds. The ability of ipecac bioaccessible fractions to inhibit reactive oxygen species (ROS) generation at cellular level was also evaluated. The findings revealed that water volume of 50 mL g⁻¹ of sample provided the maximum yield of extraction of TPC and antioxidant activity. Polyphenols increased in content and activity after digestion and they were highly bioavailable (75% of intestinal absorption). Polyphenols were also present in the residual parts which indicate a possible local activity. Results also suggest that ipecac infusion could represent a promising source of effective bioavailable antioxidants to be exploited in functional foods field.     

酒花老化评价的研究进展

酒花是啤酒生产的重要原料,确定酒花新鲜度更是保证啤酒酿造质量的关键。本文综述了国内外关于酒花老化评价的研究进展,根据酒花老化过程中苦味物质(α-酸和β-酸)、多酚和香气物质的变化情况,阐述了目前评价酒花老化程度的指标,为建立更为准确的酒花老化评价体系的研究提供一些理论参考。     

蓬蒿籽多酚提取工艺的响应面优化及其对食用油脂抗氧化活性研究

以蓬蒿籽为原料,在单因素实验基础上,采用响应面法对蓬蒿籽多酚的提取工艺条件进行优化,并对蓬蒿籽多酚的抗氧化活性进行研究。结果表明,蓬蒿籽多酚的最佳提取工艺条件为:提取温度75℃,料液比1∶27,乙醇体积分数53%,提取时间70 min。在最佳条件下,蓬蒿籽多酚得率为20.36%。蓬蒿籽多酚对猪油、菜籽油及花生油都有较强的抗氧化效果,较柠檬酸和BHA对猪油的抗氧化效果好,且与抗坏血酸、柠檬酸、BHA及BHT有协同增效作用。     

Changes of peach juices during the shelf-life and their in vitro effect on glycolipid digestion and neurotransmitter metabolism

In this study, the polyphenols content, α-amylase, α-glucosidase and cholinesterase-inhibiting activities of cloudy peach (Prunus persica) juices, were measured immediately after thermal treatment and after storage (6 months at 4 and 30 °C). The study showed that some cultivars were more useable for industry than others. Due to the high content of polyphenols and a high ability to inhibit enzymes linked to type 2 diabetes and Alzheimer's disease, noteworthy are the juices obtained from ‘Redheaven early’ and ‘Redheaven’ cultivars. The content of total phenolics ranged from 1109.7 to 390.7 mg/L of juice, and the dominant fraction was polymeric procyanidins. Following 6 months of storage a significant change was observed in the content of polyphenols, especially flavonols and anthocyanins. The data compiled from the conducted study indicate that peach juice could be useful for the juice industry as a promising source of bioactive compounds.     

Effect of different freezing methods on the bioaccessibility of strawberry polyphenols

Freezing is one of the most well-established food preservation technique that is used to prolong the shelf life and maintain the quality of strawberries. The aim of the present study was (i) to investigate the changes in polyphenols from fresh and frozen strawberries during in vitro digestion and (ii) to compare effects induced by individual quick freezing (IQF) and conventional freezing (CF). Spectrophotometric methods were used to determine total phenolics, flavonoids, anthocyanins and antioxidant capacity, whereas identification and quantification of major polyphenols were carried out using UPLC-ESI-MS/MS and HPLC-PDA, respectively. The results showed that the bioaccessible amount of major anthocyanin from frozen strawberries, i.e., pelargonidin-3-glucoside, corresponding to 72–89% of the total anthocyanins, was significantly higher than that of fresh strawberries (10.8–13.3 and 5.8 μg g⁻¹ sample, respectively; P < 0.05). Overall, the current study highlighted that freezing, independent of process type, i.e., IQF or CF, enhances the total amount of bioaccessible anthocyanins in strawberries.