Evaluation of the Health-Promoting Properties of Selected Fruits

Abstract

In this study, the health-promoting benefits of different fruits grown in Madeira Island, namely lemon (Citrus limon var. eureka), tangerine (Citrus reticulata var. setubalense), pitanga (Eugenia uniflora var. red), tomato (Solanum lycopersicum var. gordal) and uva-da-serra, an endemic blueberry (Vaccinium padifolium Sm.), were investigated. The phenolic composition (total phenolics and total flavonoids content) and antioxidant capacity (assessed through ABTS and DPPH assays) were measured revealing a high phenolic potential for all fruits, except tomato, while uva-da-serra is particularly rich in flavonoids. In relation to the antioxidant capacity, the highest values were obtained for pitanga and uva-da-serra extracts. The bioactive potential was also assessed through the ability of the extracts to inhibit digestive enzymes linked to diabetes (α-amylase, α- and β-glucosidases) and hypertension (angiotensin-converting enzyme, ACE). The results obtained point to a very high bioactive potential with the selected samples exhibiting very important ACE anti-enzymatic capacities. A statistical analysis of the obtained data reveals a very strong correlation between ABTS and TPC, and a strong contribution of the fruit polyphenols for enzyme inhibition, and thus, presenting high antihypertensive and antidiabetic capacities. Overall, the results obtained clearly show a high bioactive potential of the selected fruits that should be further studied, in terms of specific phenolic composition. Moreover, these results strongly support the valorisation of pitanga seeds usually discarded as a waste, and uva-da-serra, an endemic and wild bush, as potential bioresources of bioactive compounds with impact in human diet.

Bioactive Compounds and Antioxidant Activity from Spent Coffee Grounds as a Powerful Approach for Its Valorization

“…The total phenolic content (TPC) of the spent coffee grounds was determined using the Folin–Ciocalteu procedure, as described by Figueira et al [ 66 ], with a few modifications. Briefly, the extracts obtained by the µ-QuEChERS procedure were diluted in water up to a 3 mL final volume.…”

Impact of Grass Pea Sweet Miso Incorporation in Vegan Emulsions: Rheological, Nutritional and Bioactive Properties

“…The antioxidant capacity of the samples was measured using two different methodologies, also using gallic acid as standard (results in GAE). The scavenging effect of extracts was determined using the DPPH (2,2-diphenyl-1-picrylhydrazyl-hydrate) method [ 42 , 43 , 44 ]. Extracts were mixed with a methanolic solution of DPPH (1:25 v / v ) and kept out of direct light for 1 h at 20 °C before measurement.…”

Application of Natural Edible Coating to Enhance the Shelf Life of Red Fruits and Their Bioactive Content

“…It is commonly recognized that consuming fruits and vegetables provides significant health benefits and helps to protect against many ailments. Cheung et al (2021) emphasized that consuming a diverse range of fruits and vegetables daily might significantly lower the risk of death [1], particularly in relation to cardiovascular disease, chronic illnesses, and cancer [2]. Red fruits, commonly referred to as berries, are diminutive fruits which are highly valued for their crimson color, tangysweet flavor, and advantageous effects on well-being [3].…”