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We aimed to study the obtention of valuable phenolic compounds from tissue by-products of agro-industrial processing of apple (GS) and strawberry (RF) using green solvents and Soxhlet extraction methodology. The effects of solvent type [water (W); 80% ethanol, (EtOH)] and extraction ratio (1:10, 1:20, 1:30, and 1:40 p/v) were determined on total phenolic content (TPC), antioxidant capacity (DPPH), and the profile of phenolic compounds of the GS and RF extracts. The solvent type and the extraction ratio significantly affected TPC and DPPH of GS and RF extracts. Extraction with EtOH and 1:40 ratio produced the highest yields, obtaining an RF extract with 15.8 g GAE/Kg (TPC) and 19 mmol TE/Kg (DPPH). The tetra-galloyl glucose isomer and agrimoniin (0.8-0.4 g/Kg) were the main RF phenolic compounds of the eight identified. GS extract, obtained with EtOH and 1:40 ratio, had 11.9 g GAE/Kg (TPC) and 20.5 mmol TE/Kg (DPPH), having quercetin -3-o-glucuronide (0.43 g/Kg) the highest concentration among the eight phenolic compounds identified. The results highlight the potential of green solvents to obtain valuable compounds from low-cost raw materials, like the high-antioxidant capacity phenolic compound extracts obtained herein. Highlights: • Valuable bioactive compounds can be extracted from strawberry and apple agro-industrial waste. • Extraction parameters affected phenolic compound profile and antioxidant capacity. • Apple and strawberry by-products are low-cost sources of hydrolysable tannins and flavonols. • Green solvents used for biowaste valorisation can help in circular economy transformation.

Humans have consumed foods made from beans from the Theobroma cacao tree for centuries. Already Aztec warriors supported the cocoa powder drink before the battle. In modern society, chocolate has been known for its good taste. Earlier, chocolate used to be criticized for its fat content and its consumption was a sin rather than a remedy, associated with acne, caries, obesity, high blood pressure, coronary artery disease and diabetes. However, the recent discovery of biologically active phenolic compounds in cocoa has changed this perception[14]. Flavonoids, including catechin, epicatechin, and procyanidins predominate in antioxidant activity. Nowadays, in many studies discuss the recent progresses on potential health benefits of cocoa, with a focus on the areas that have been paid little attention so far, such as the role of cocoa in immune regulation, inflammation, neuroprotection, oxidative stress, obesity, and diabetes control[12]. The purpose of this review is to interpret research done in the last decade on the benefits of chocolate consumption.

Context: Previous reports informed about the species-specific condition of plant phenolic profiles and the association between phenolic composition and plant antioxidant properties. The species-specific condition of phenolic patterns offers the opportunity to develop chemical quality markers for plants used in traditional medicine. However, changes in phenolic composition can occur during plant growth. Physalis angulata is an important medicinal plant for which the age-related variation of phenolic composition and antioxidant properties is unknown. Aims: To assess the phenolic composition and antioxidant properties of above- and under-ground parts of P. angulata at four growth stages and evaluate their potential as chemical quality indicators. Methods: A method of HPLC-DAD was used to assess the phenolic profiles. Anti-radical potential, total antioxidant capacity and iron reducing power were evaluated by spectrometric methods. Sample distinctiveness was determined by cluster analyses. Results: The HPLC-DAD analysis revealed 21 phenolic compounds, which were accumulated in a tissue- and age-specific manner. On the contrary, a clear distinctiveness between phenolic contents and antioxidant properties of samples was not observed. Mature flowers highlighted for its total phenolic content (6.50 mg/g fresh tissue) and total antioxidant capacity (416.1 µg/mL). Young leaves were outstanding for its flavonoid content (37.86 µg/g fresh tissue) and reducing power (A700nm = 4.04). Immature calyces were worthy for its phenolic acid concentration (1.28 µg/g fresh tissue) and its free radical scavenging activity (EC50 = 0.12 mg/mL). Conclusions: Phenolic profiles represent reliable chemical quality indicators for determining plant age, tissular origin, authenticity, and adulteration of herbal preparations of P. angulata.

Objective: Our objective in this study was to evaluate and compare the therapeutic potency (bronchodilation, action on ciliary beat frequency, anti-inflammatory, anti-remodelling effect) of a different flavonol derivates: quercetin, fisetin and morin in the setting of experimentally induced allergic asthma. Methods: Using an experimental model of allergic asthma, we evaluated the anti-asthmatic potential of flavonols either after acute or long-term (21 days) treatment of ovalbumin-sensitized guinea pigs. In light of this fact, we measured the following parameters: in vivo changes in specific airways resistance; ciliary beat frequency was estimated using a high-speed video camera; the levels of Th2 cytokines in bronchoalveolar lavage fluid and TGF-apha-1 in lung homogenate were determined using multiple analysis. Results: The data showed that only acute administration of fisetin resulted in significant bronchodilation. The experimental results were indicative of significant bronchodilatory, anti-inflammatory, anti-remodelling effects exerted by quercetin chronic therapy. The data demonstrate that long-term morin administration resulted in bronchodilator effect like that of long-acting β2-agonists, an anti-inflammatory effect like that of corticosteroid, budesonide. Although a significant increase ciliary beat frequency was noticed in ovalbumin-sensitized guinea pigs, neither morin nor quercetin influence ciliary beat frequency. Conclusions: In summary, flavonol derivates morin, fisetin and quercetin represent very rational targets for additional studies as potential substance for control as well as prevention of asthma inflammation and symptoms.

The antioxidant potential of 80% methanolic extracts of some agro wastes (pomegranate peel, apple peel, banana peel, citrus peel, corncob, wheat husk, wheat bran, rice bran, and rice hull) was assessed. The yields of the extracts varied over a wide range (8.83 to 29.9 g/100g of dry weight). TPC, TFC, total flavonols (kaempeferol, quercetin, myricetin; HPLC method), DPPH. radical scavenging and inhibition of linoleic acid peroxidation for the extracts varied significantly (P < 0.05) ranging from 0.16-36.40, 0.026-4.89 g/100g of dry matter, 1.06-2622.41 mg/Kg of dry matter, 11.2-52.6, and 64.8-96.4%, respectively. Pomegranate peel extract, offering the highest TPC, TFC, and total flavonols exhibited superior antioxidant activity followed by apple peel, citrus peel, banana peel, corncob, wheat bran, rice bran, wheat husk, and rice hull. Furthermore, the antioxidant effectiveness of the extracts was assessed using corn oil (CO) as the oxidation substrate. CO samples stabilized with extracts at a concentration of 600 ppm (w/w) were subjected to accelerated aging (60 ºC, oven heating, 30 days; 8 h heating cycle per day), and analyzed periodically for the extent of oxidative alterations following the measurement of conjugated dienes (CD), conjugated trienes (CT), p-anisidine and peroxide values. The correlation between the results of different antioxidant assays and oxidation parameters investigated in the present study indicated that fruit peel extracts, exhibiting higher TPC, TFC, flavonol and scavenging power, were also more potent for enhancing the oxidative stability of corn oil.

This research deals with the chemical study and evaluation of the phytotoxic effects of the methanol extract of E. flavescens leaves. The compounds were isolated using classic chromatographic techniques and the identification of the phenolic profile was proposed from the HPLC/DAD/MS-MS data. Structure elucidation of the compounds was performed by 1H and 13C (1D e 2D) NMR techniques and HRMS. The chemical study led to the isolation of betulinic acid (1) and lupeol (2), identified in mixture quercitrin (3) and catechin (4) beyond myricetrin (5) in mixture with (3). In addition, several phenolic compounds were identified, among them, flavonoids and phenolic acids. For bioassays phytotoxic effect were used as test plants two invasive species, M. pudica and S. obtusifolia. The methanol extract showed significant seed germination inhibition. The triterpenoid 1 showed low inhibition effects on seed germination and moderate effects on radicle and hypocotyl growth. The mixture of flavonoids 3/4 showed effective phytotoxic effects, inhibiting 92,1% of the seed germination of M. pudica and 63,0% of S. obtusifolia. Inhibitions of 72,5% and 76,1% of M. pudica radicle and hypocotyl growths were observed, respectively, and 74,5% and 78,0% of S. obtusifolia for the same bioassays, respectively.

Smilax campestris Griseb. -Smilacaceae- es una especie empleada en la medicina popular. Sus hojas se utilizan en infusiones para la elaboración de bebidas tónicas, amargas y digestivas. El objetivo de este trabajo es la comparación de las variaciones cuali-cuantitativas en el contenido de los polifenoles de las hojas de S. campestris sanas con las atacadas por la oruga de la mariposa Agraulis vanillae L. -Heliconidae-. En las hojas atacadas se determinaron mayores concentraciones de los derivados de quercetina, canferol e isoramnetina con respecto a las hojas sanas. Además, se producen nuevas glicosidaciones que no están presentes en las hojas sanas. La concentración de fenoles totales es de 3,46 ± 0,62 mg de ácido tánico/gramo de material fresco en hojas sanas y de 12,96 ± 2,06 mg de ácido tánico/gramo de material fresco en hojas atacadas. Estos resultados concuerdan con estudios realizados en otras especies vegetales, donde la acción de los herbívoros genera aumento en los niveles de polifenoles. Por lo tanto, se deduce que las hojas de S. campestris modifican el metabolismo de los polifenoles como mecanismo de defensa contra predadores.

Smilax campestris Griseb. -Smilacaceae- es una especie empleada en la medicina popular. Sus hojas se utilizan en infusiones para la elaboración de bebidas tónicas, amargas y digestivas. El objetivo de este trabajo es la comparación de las variaciones cuali-cuantitativas en el contenido de los polifenoles de las hojas de S. campestris sanas con las atacadas por la oruga de la mariposa Agraulis vanillae L. -Heliconidae-. En las hojas atacadas se determinaron mayores concentraciones de los derivados de quercetina, canferol e isoramnetina con respecto a las hojas sanas. Además, se producen nuevas glicosidaciones que no están presentes en las hojas sanas. La concentración de fenoles totales es de 3,46 ± 0,62 mg de ácido tánico/gramo de material fresco en hojas sanas y de 12,96 ± 2,06 mg de ácido tánico/gramo de material fresco en hojas atacadas. Estos resultados concuerdan con estudios realizados en otras especies vegetales, donde la acción de los herbívoros genera aumento en los niveles de polifenoles. Por lo tanto, se deduce que las hojas de S. campestris modifican el metabolismo de los polifenoles como mecanismo de defensa contra predadores.