Romeo Rojas

Impact of extraction techniques on antioxidant capacities and phytochemical composition of polyphenol-rich extracts.

In this work, impact of extraction methods (maceration, decoction, MAE, and UAE) on TPC, antioxidant activity, and the mass fraction of phenolics in several plant extracts (Punica granatum, Juglans regia, Moringa oleifera, and Cassia fistula) was investigated. The results showed that, despite the nature of matrix, the highest values of TPC in all samples were obtained by MAE as follows: PP (18.92±0.11), ML (15.19±0.11), HL (12.69±0.16), and WS (12.80±0.11) mg GAEg-1 respectively, and exhibited potent antioxidant activity (from 0.28±0.01 to 5.34±0.02mgGAEg-1), representing sources of powerful antioxidants. The LC-MS2 analysis revealed a wide range of phenolics, highlighting their content in phenolic acids, flavonoids and lignans. The presence of different phenol molecules demonstrated that the extraction method had influence on phytochemical profile. Finally, due to its high extraction efficiency, MAE was the more effective extraction technique.

Fluctuations in phenolic content, ascorbic acid and total carotenoids and antioxidant activity of fruit beverages during storage

Stability of the total phenolic content, ascorbic acid, total carotenoids and antioxidant activity in eight fruit beverages was analyzed. The influence of storage temperature (4, 8 and 11 °C) during the product shelf-life (20 days) was evaluated. Pomegranate Juice presented the highest values for antioxidant activity by DPPH• assay (552.93 ± 6.00 GAE μg mL−1), total carotenoids (3.18 ± 0.11 βCE μg mL−1), and total phenolic content (3967.07 ± 2.47 GAE μg mL−1); while Splash Blend recorded the highest levels of ascorbic acid (607.39 ± 2.13 AAE μg mL−1). The antioxidant capacity was stable at 4 and 8 °C for the first 8 days of storage; while carotenoids and ascorbic acid were slightly degraded through the storage time, possibly due to oxidation and/or reactions with other compounds. The results suggest that the observed variation during testing could be related to storage conditions of the final product.

Moringa plants: Bioactive compounds and promising applications in food products

Moringa plants have an extensive range of bioactive compounds that can be obtained from different vegetative structures, such as leaves, seeds, stems and pod husks. These bioactive molecules include carbohydrates, phenolic compounds, oils and fatty acids, proteins and functional peptides and have great potential to be used in several formulations of food products. This report collects recent information concerning bioactive molecules in other species of the Moringaceae family, different from Moringa oleifera. Thus, this document aims to describe these bioactive compounds and their functional properties on foodstuffs. In addition, more suitable methodologies applied for their extraction and characterization are reviewed. Finally, an overview of patents required to protect Moringa-derived products and processes is provided.

Phenolic Compounds Recovery from Grape Fruit and By- Products: An Overview of Extraction Methods

Phenolic compounds are considered as bioactive compounds having beneficial effects on human health. Because of their biological properties, they have wide applications on pharmaceutical and food industries, and for this reason, it is important to identify most appropriate procedures, which permits the standardization for recovery of these compounds from several plant materials including grapes. Grape fruit and by-products are excellent sources of bioactive compounds such as pigments, organic acids, and phenolic compounds. Several convectional and emerging technologies have been evaluated in order to recover phenolic compounds from grape fruits and wastes such as chemical, physical, and biotechnological techniques, which offer different advantages related to economic, environmental, time-saving, and yield aspects. Nowadays, there is no updated information, which provides an overview about the techniques applied of these bioactive compound recovery in order to obtain high-quality and high-activity extracts rich in phenolic compounds from grape fruit and by-products. This chapter offers relevant aspects related to the techniques employed during the last five years by researches for phenolic compound recovery from grapes.

Improvement of Shelf Life and Sensory Quality of Pears Using a Specialized Edible Coating

An edible coating functionalized with pomegranate polyphenols was designed. Different blends of candelilla wax, gum arabic, jojoba oil, and pomegranate polyphenols were formulated in order to improve the shelf life quality of pears (variety Bartlett), and all formulations were applied by immersion onto the fruit surface. Coated pears with and without polyphenols and uncoated pears (control) were stored under the same conditions. Fruits were analyzed to evaluate changes in their physicochemical, microbiological, and sensorial properties during 30 days of storage at room temperature. Coated pears coded as T13 (candelilla wax 3%, gum arabic 4%, jojoba oil 0.15%, and pomegranate polyphenols 0.015%) extended and improved their shelf life quality due to the minimization of the physic-chemical changes and sensorial properties. Therefore, the results indicated that the formulated edible coating has potential to extend the shelf life and maintain quality of pears. It was probed that coated pears were accepted for consumers as a good product. Edible coating application represents a good alternative to keep pears freshness for longer periods.

UPLC-ESI-QTOF-MS2-Based Identification and Antioxidant Activity Assessment of Phenolic Compounds from Red Corn Cob (Zea mays L.)

In this study, the extraction of phenolic antioxidants from red corn cob was carried out using ultrasound-assisted extraction (UAE). The solid:liquid ratio and extraction time were evaluated when obtaining these bioactive compounds. The total phenolic contents were evaluated using the Folin Ciocalteu method, while the antioxidant activity was measured by ABTS•+ and DPPH• assays. The amount of phenolic compounds ranged from 215.17 ± 33.49 to 527.33 ± 103.79 GAE mg/100 g and, overall, high solid:liquid ratios and time periods release more phenolic compounds. Moreover, the red corn cob extracts showed higher radical scavenging capacity according to the results obtained using the ABTS•+ technique compared to the DPPH• test. The coupling of liquid chromatography and mass spectrometry assay allowed the determination of 11 phenolic compounds, including phenolic acids and flavonoids. Thus, our results demonstrated for the first time the potential of red corn cob as a source of bioactive compounds, which might be included in food and pharmacological preparations.