Phenolics present in the free, esterified, glycosylated and insoluble-bound forms of araticum pulp, peel and seed were for the first time characterized and quantified using HPLC-ESI-MS/MS. Levels of total phenolics, flavonoids, condensed tannins and antioxidant activities from araticum fruit followed the order peel > pulp > seed. Overall, insoluble-bound and esterified phenolics were the dominant forms of phenolics from araticum fruit parts and the highest contributors to their antioxidant activities. Extracts were found to contain contrasting levels of phenolics that were specific to each fruit part. From 10 phenolics quantified in araticum fruit, catechin and epicatechin were the major ones from pulp and peel, whereas seed displayed caffeic acid, catechin and epicatechin as its main phenolics. Araticum fruit was found to provide a good source of phenolics, and the full exploitation of this fruit may find applications in the food, cosmetic and pharmaceutical industries.

No abstract

Soluble carbohydrates, volatile and phenolic compounds from calabura fruit as well as its antioxidant activity were assessed. The low amount of fermentable oligo-, di-, and monosaccharides and polyols (FODMAPs) and similar amount of glucose and fructose allow us to classify the calabura berry as low-FODMAPs. The terpenes β-Farnesene and dendrolasin identified by SPME-GC-MS were the major volatile components. UHPLC-MS/MS analysis revelled gallic acid (5325 μg/g dw) and cyanidin-3-O-glucoside (171 μg/g dw) as the main phenolic compounds, followed by gentisic acid, gallocatechin, caffeic acid and protocatechuic acid. In addition, gallic acid was found mainly in esterified (2883 μg/g dw) and insoluble-bound (2272 μg/g dw) forms. Free and glycosylated forms showed however the highest antioxidant activity due to occurrence of flavonoids (0.28-27 μg/g dw) in these fractions, such as catechin, gallocatechin, epigallocatechin, naringenin, and quercetin. These findings clearly suggest that calabura is a berry with low energy value and attractive colour and flavour that may contribute to the intake of several bioactive compounds with antioxidant activity. Furthermore, this berry have great potential for use in the food industry and as functional food.

In this work, we investigated the effects of the nominal ultrasonic power (160-640 W) and process time (0.5-5.0 min) on the phenolic compounds recovery and antioxidant activity from araticum peel. The individual and synergistic effects of the process variables on the phenolic recovery were estimated using a full factorial experimental design. Operating at high nominal ultrasonic powers was possible to obtain high phenolic yields and antioxidant activities at short process times (≤5 min). The HPLC-ESI-QTOF-MS/MS analysis revealed that the araticum peel sample possessed 142 phytochemicals, 123 of which had not been reported in the literature for this raw material yet. The most abundant phenolic compounds recovered were epicatechin, rutin, chlorogenic acid, catechin and ferulic acid. Thus, high-intensity ultrasound technology proved to be a simple, efficient, fast and low environmental impact method for obtaining phenolic compounds from araticum peel. In addition, araticum peel showed to be a promising source bioactive natural phenolics for further applications in the food, nutraceutical, cosmetic and pharmaceutical industries.

Homogenizer-assisted extraction (HAE) was employed in the recovery of total phenolic compounds (TPC) from banana peel. The effects of ethanol concentration v/v, EC) and the solid-solvent ratio (2.5-7.5%, w/v, SSR) on the TPC extraction from banana peel were evaluated using response surface methodology. The best TPC extraction conditions from banana peel were defined as ethanol concentration of 54% (v/v) and solid-solvent ratio of 7.5% (w/v). The HAE in optimum conditions was able to extract a high TPC content (2.44 g GAE/ 100 g dw) from banana peel with just 30 s of extraction. In addition, the extract showed high antioxidant activity in the different assays used (DPPH IC 50 , TEAC and T-ORAC FL ). HAE can be employed in the safe, fast and low environmental impact extraction of antioxidant compounds from plant material. Furthermore, banana peels can be considered as a renewable and low-cost source of antioxidant compounds. PRACTICAL APPLICATIONSExtraction of antioxidants from banana peel using HAE presents more potential than traditional extraction methods, due to a lot of decrease of extraction time (30 s), low energy expenditure as the system is not heated and also the use of GRAS solvent (water : ethanol). The banana peel extract obtained in optimal conditions presents high potential, for example, it can be applied as preservatives in the food and beverage, besides others uses in pharmaceutical and cosmetic industries. The banana peel is a cheap plant material and available throughout the year; therefore, it is an excellent raw material for the extraction of natural compounds. The use of banana peel to obtain antioxidant extracts is a practical alternative for increasing the value of this by-product. a wide variety of applications in food science and technology mainly because of their properties as antioxidant and antimicrobial agents. In addition, the consumption of fruits rich in (poly)phenols can prevent, slow or reverse the development of diseases, such as cancer, cardiovascular diseases and neurological disorders (Vald es et al. 2015).