Structure-based design of new N-benzyl-piperidine derivatives as multitarget-directed AChE/BuChE inhibitors for Alzheimer's disease.

The pathogenic complexity of Alzheimer's disease (AD) demands the development of multitarget-directed agents aiming at improving actual pharmacotherapy. Based on the cholinergic hypothesis and considering the well-established role of butyrylcholinesterase (BuChE) in advanced stages of AD, the chemical structure of the acetylcholinesterase (AChE) inhibitor drug donepezil (1) was rationally modified for the design of new N-benzyl-piperidine derivatives (4a-d) as potential multitarget-direct AChE and BuChE inhibitors. The designed analogues were further studied through the integration of in silico and in vitro methods. ADMET predictions showed that 4a-d are anticipated to be orally bioavailable, able to cross the blood-brain barrier and be retained in the brain, and to have low toxicity. Computational docking and molecular dynamics indicated the formation of favorable complexes between 4a-d and both cholinesterases. Derivative 4a presented the lowest binding free energy estimation due to interaction with key residues from both target enzymes (-36.69 ± 4.47 and -32.23 ± 3.99 kcal/mol with AChE and BuChE, respectively). The in vitro enzymatic assay demonstrated that 4a was the most potent inhibitor of AChE (IC50 2.08 ± 0.16 µM) and BuChE (IC50 7.41 ± 0.44 µM), corroborating the in silico results and highlighting 4a as a novel multitarget-directed AChE/BuChE inhibitor.

Production of Bioactive Peptides from Baltic Herring (Clupea harengus membras): Dipeptidyl Peptidase-4 Inhibitory, Antioxidant and Antiproliferative Properties.

This study aimed to produce bioactive protein hydrolysates from undervalued fish, namely Baltic herring, and its filleting by-products. Protein hydrolysates were produced with Alcalase and Flavourzyme to achieve effective hydrolysis. The hydrolysates were evaluated for chemical composition, molecular weight distribution, antioxidant capacity, dipeptidyl-peptidase 4 (DPP4) inhibitory activity, effects on cell proliferation and surface hydrophobicity. The protein content of the hydrolysates was high, from 86% to 91% (dm), while the fat content was low, from 0.3% to 0.4% (dm). The hydrolysates showed high DPP4 inhibition activities with IC50 values from 5.38 mg/mL to 7.92 mg/mL. The scavenging activity of the hydrolysates towards DPPH was low, but an intermediate Folin-Ciocalteu reducing capacity and Cu2+ chelating ability was observed. The solid phase extraction with Sep-Pak C18 cartridges increased the DPP4 inhibition activity and antioxidant capacity, indicating peptides' crucial role in the bioactivities. The cytotoxicity of the hydrolysates was evaluated on the HCT8, IMR90, and A549 cell lines. The hydrolysates inhibited cell growth in the cancer and normal cells, although they did not reduce cell viability and were not lethal. Overall, our results indicate that protein hydrolysates from Baltic herring have potential as health-promoting foods and nutraceuticals, especially for enhancing healthy blood glucose regulation.

Chemical Composition, Antioxidant, Antimicrobial and Cytotoxic/Cytoprotective Activity of Non-Polar Extracts of Grape (Vitis labrusca cv. Bordeaux) and Blackberry (Rubus fruticosus) Seeds.

The aim of this study was to compare the influence of the extraction method, chemical composition, antimicrobial effects, antioxidant activity, and cytotoxicity on human cells of the non-polar extracts of grape (Vitis labrusca) and blackberry (Rubus fruticosus) seeds. The Soxhlet (Sox), Bligh-Dyer (BD), and ultrasound (US) methods were used for extractions. For blackberry non-polar seed extract, extraction via the BD method showed the highest mean values of total phenolic content (TPC), expressed in milligrams of gallic acid equivalent per 100 mL of non-polar seed extracts (102.37 mg GAE/100 mL), and higher antioxidant activity in relation to the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, expressed in milligrams of gallic acid equivalent per 100 mL of non-polar seed extracts (11.50 mg AAE/100 mL), if compared with the Sox and US extractions. Similar results were obtained for the non-polar grape seed extracts, where BD extraction obtained the highest values for TPC (28.61 mg GAE/100 mL) and DPPH (35.36 mg AAE/100 mL). The type of extraction method had an impact on the composition of fatty acids. Only the non-polar blackberry and grape seed extracts obtained via the Sox method showed some in vitro inhibitory effect against Escherichia coli (IAL 2064) and Staphylococcus aureus (ATCC 13565). Regardless of the extraction method used, the non-polar blackberry and grape seed extracts did not decrease the cell viability (IC50 >1000 µg/mL) of cancer and normal cell lines, thus indicating the relative safety of the extracts. All the seed extracts decreased the generation of reactive oxygen species in the cell lines. Blackberry and grape seed lipid fractions can be utilized as antioxidants, and the extraction methods used cause significant changes in relation to their bioactivity and chemical composition.

Selina-1,3,7(11)-trien-8-one and Oxidoselina-1,3,7(11)-trien-8-one from Eugenia uniflora Leaf Essential Oil and Their Cytotoxic Effects on Human Cell Lines.

The sesquiterpenes selina-1,3,7(11)-trien-8-one and oxidoselina-1,3,7(11)-trien-8-one were isolated from the essential oil of Eugenia uniflora L. leaves. The structures were elucidated using spectrometric methods (UV, GC-MS, NMR, and specific optical rotation). The relationship between antioxidant activity, as determined by DPPH assay, and the cytotoxic effect was evaluated using tumor cells, namely lung adenocarcinoma epithelial cells (A549) and human hepatoma carcinoma cells (HepG2), as well as a model of normal human lung fibroblast cells (IMR90). Both compounds did not show prominent free-radical scavenging activity according to DPPH assay, and did not inhibit lipid peroxidation in Wistar rat brain homogenate. The isolated compounds showed pro-oxidative effects and cytotoxicity in relation to the IMR90 cell line.

Cinnamoyl-N-Acylhydrazone-Donepezil Hybrids: Synthesis and Evaluation of Novel Multifunctional Ligands Against Neurodegenerative Diseases.

A new series of ten multifunctional Cinnamoyl-N-acylhydrazone-donepezil hybrids was synthesized and evaluated as multifunctional ligands against neurodegenerative diseases. The molecular hybridization approach was based on the combination of 1-benzyl-4-piperidine fragment from the anti-Alzheimer AChE inhibitor donepezil (1) and the cinnamoyl subunit from curcumin (2), a natural product with remarkable antioxidant, neuroprotective and anti-inflammatory properties, using a N-acylhydrazone fragment as a spacer subunit. Compounds 4a and 4d showed moderate inhibitory activity towards AChE with IC50 values of 13.04 and 9.1 µM, respectively. In addition, compound 4a and 4d showed a similar predicted binding mode to that observed for donepezil in the molecular docking studies. On the other hand, compounds 4a and 4c exhibited significant radical scavenging activity, showing the best effects on the DPPH test and also exhibited a significant protective neuronal cell viability exposed to t-BuOOH and against 6-OHDA insult to prevent the oxidative stress in Parkinson's disease. Similarly, compound 4c was capable to prevent the ROS formation, with indirect antioxidant activity increasing intracellular GSH levels and the ability to counteract the neurotoxicity induced by both OAß1-42 and 3-NP. In addition, ADMET in silico prediction indicated that both compounds 4a and 4c did not show relevant toxic effects. Due to their above-mentioned biological properties, compounds 4a and 4c could be explored as lead compounds in search of more effective and low toxic small molecules with multiple neuroprotective effects for neurodegenerative diseases.

From byproduct to a functional ingredient: Camu-camu (Myrciaria dubia) seed extract as an antioxidant agent in a yogurt model.

This work aimed to characterize the phenolic composition and in vitro antioxidant and antiproliferative properties of lyophilized camu-camu (Myrciaria dubia) seed extract (LCE), and to assess the effects of LCE on the antioxidant and sensory traits of yogurt. The LCE contained 46.3% (wt/wt) total phenolic content; the main compounds quantified were vescalagin, castalagin, gallic acid, procyanidin A2, and (-)-epicatechin. The LCE had antioxidant activity, as measured by different chemical assays (2,2-diphenyl-1-picrylhydrazyl, Folin-Ciocalteu reducing capacity, total reducing capacity, ferric reducing antioxidant power, and Cu2+ chelating capacity), and inhibited the cell proliferation of HepG2 cells (human hepatoma carcinoma; IC50 = 1,116 µg/mL) and Caco-2 cells (human colorectal adenocarcinoma epithelial cells; IC50 = 608.5 µg/mL). In addition, LCE inhibited the in vitro activity of α-amylase, α-glucosidase, and angiotensin-converting enzyme, and protected DNA from peroxyl radical-induced scission. When added to yogurts, different concentrations of LCE (0, 0.25, 0.5, 0.75, and 1.0 g/100 g) increased the chemical antioxidant and reducing capacities. The camu-camu yogurt containing LCE at 0.25 g/100 g had an acceptance index of 84%, showing that camu-camu seed extract may be a potential ingredient for addition to yogurts.

Design, Synthesis and Biological Evaluation of Novel Triazole N-acylhydrazone Hybrids for Alzheimer's Disease.

Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder that involves different pathogenic mechanisms. In this regard, the goal of this study was the design and synthesis of new compounds with multifunctional pharmacological activity by molecular hybridization of structural fragments of curcumin and resveratrol connected by an N-acyl-hydrazone function linked to a 1,4-disubstituted triazole system. Among these hybrid compounds, derivative 3e showed the ability to inhibit acetylcholinesterase activity, the intracellular formation of reactive oxygen species as well as the neurotoxicity elicited by Aß42 oligomers in neuronal SH-SY5Y cells. In parallel, compound 3e showed a good profile of safety and ADME parameters. Taken together, these results suggest that 3e could be considered a lead compound for the further development of AD therapeutics.

Camu-camu (Myrciaria dubia) from commercial cultivation has higher levels of bioactive compounds than native cultivation (Amazon Forest) and presents antimutagenic effects in vivo.

BACKGROUND: Camu-camu (Myrciaria dubia) is a typical Amazonian fruit and has high antioxidant capacity due to its high levels of vitamin C and phenolic compounds. This study aimed to determine the phytochemicals, antioxidant capacity and antimutagenic effects of camu-camu fruits with different maturity stages grown in dry (commercial cultivation) or flooded environments (native cultivation, Amazon). RESULTS: Total polyphenols, ascorbic acid and in vitro antioxidant capacity levels were higher in ripe fruits grown in a commercial cultivation. The extracts from ripe camu-camu grown in a commercial cultivation exerted antioxidant effects and high percentage of protection against doxorubicin and 1,2-dimethylhydrazine in all tested systems (liver, bone marrow and gut), for three camu-camu extract concentrations (17, 85 and 170 mg kg-1 body weight), as follows: bone marrow minocronucleus (37.91%, 41.75%, 43.95%); micronucleus gut test (61.01%, 64.40%, 50.28%); apoptosis index (60.26%, 62.44%, 58.22%); comet assay through the tail moment (71.64%, 72.31%, 70.70%), percent DNA in the tail (64.54%, 68.75%, 76.79%) and tail intensity (76.43%, 81.02%, 68.33%). CONCLUSION: The results of this study contribute to increasing the production of camu-camu fruits grown in dry environments and their use as a health-promoting food. © 2018 Society of Chemical Industry.

Physico-chemical properties, rheology and degree of esterification of passion fruit (Passiflora edulis f. flavicarpa) peel flour.

BACKGROUND: The peel of yellow passion fruit is as an agro-industrial waste of great environmental impact, representing more than 50% of the total weight of the fruit. For this reason, and also considering its importance as a source of functional components such as pectin, this organic waste is increasingly attracting the attention of researchers. The aim of this study was to investigate the physico-chemical composition and physical properties of this material, which may be of interest to the food industry. RESULTS: We obtained two samples of passion fruit peel flour applying different processes: flour without treatment (FWOT) and flour with treatment by maceration (FWT). It was found that the flour samples contain, respectively, 372.4 g kg-1 and 246.7 kg-1 of soluble fiber and, according to the FTIR analysis, this material corresponds to high and low methoxyl pectins, respectively. CONCLUSION: The flour obtained by maceration (FWT) offers greater benefits for industrial use, with 60% fewer tannins and greater thermal stability. In addition, this sample does not reabsorb moisture as easily, although FWOT also shows potential for use in dietary products. Considering the pseudoplastic properties of the flours, the application of both samples could be expanded to many industrial sectors. © 2017 Society of Chemical Industry.

Bridging the gap in antioxidant activity of flavonoids: Correlating the oxidation of human plasma with chemical and cellular assays.

Traditional antioxidant screening relies on chemical assays to assess compounds' potential in combating oxidative processes. However, translating chemical antioxidant activity to complex biological systems poses challenges. In this study, the antioxidant potential of fruit-derived phenolic compounds, hyperoside (HP), epicatechin (EC), and phlorizin (PZ), and their combinations in a specific ratio were investigated using a simplex-centroid design of experiments. The research included in vitro antioxidant assays, plasma protection against oxidation tests, and cytotoxicity assessments in human cell lines. The results revealed the complex relationship between chemical antioxidant activity and its relevance to cellular oxidative and antioxidative processes. HP and EC exhibited significant antioxidant activity, with HP outperforming EC in multiple assessments. Cytotoxicity assay confirmed that these compounds did not induce cell death or hinder proliferation, even at higher concentrations (>100 µmol/mL). In the cell antioxidant activity (CAA) test, HP and EC exhibited higher CAA, while PZ displayed lower antioxidant activity. In conclusion, a synergistic effect emerged when HP, EC, and PZ were combined, particularly in plasma protection, suggesting protective effects and potential health benefits. This research emphasized the need for a nuanced understanding of the interplay between chemical assays and cellular behavior in comprehending the relationship between chemical-based, human plasma oxidation, and CAA.

Effectiveness of anthocyanin-containing foods and nutraceuticals in mitigating oxidative stress, inflammation, and cardiovascular health-related biomarkers: a systematic review of animal and human interventions.

Cardiovascular diseases (CVDs) are a group of chronic health disorders prevalent worldwide that claim millions of lives yearly. Inflammation and oxidative stress are intricately associated with myocardial tissue damage, endothelial dysfunction, and increased odds of heart failure. Thus, dietary strategies aimed at decreasing the odds of CVDs are paramount. In this regard, the consumption of anthocyanins, natural pigments found in edible flowers, fruits, and vegetables, has attracted attention due to their potential to promote cardiovascular health. The main mechanisms of action linked with their protective effects on antioxidant and anti-inflammatory activities, serum lipid profile modulation, and other cardiovascular health parameters are explained and exemplified. However, little is known about the dose-dependency nature of the effects, which anthocyanin has better efficiency, and whether anthocyanin-containing foods display better in vivo efficacy than nutraceuticals (i.e., concentrated extracts containing higher levels of anthocyanins than foods). Thus, this systematic review focused on determining the effects of anthocyanin-containing foods and nutraceuticals on biomarkers associated with CVDs using animal studies and human interventions supported by in vitro mechanistic insights. Overall, the results showed that the regular consumption of anthocyanin-containing foods and nutraceuticals improved vascular function, lipid profile, and antioxidant and anti-inflammatory effects. The daily dosage, the participants' health status, and the duration of the intervention also significantly influenced the results.

Bioaccessibility of bioactive compounds from Pereskia aculeata and their cellular antioxidant effect.

Ora-pro-nobis (Pereskia aculeata) is a Cactaceae plant with edible leaves and fruits whose extracts are consumed to promote health, albeit bioactive compounds' bioaccessibility was still not assessed. To address this, ora-pro-nobis fruits (FE) and leaf extracts (LE) were subjected to in vitro digestion to better understand how this process impacts the bioactivities of the extracts. The study investigated the composition of the extracts, their cytotoxicity, and their chemical, plasmatic, and cellular antioxidant capacity. The results revealed that total polyphenolics were about 70% bioaccessible in LE and FE, with phenylalanine being the most bioaccessible essential amino acid in leaves (42.7%) and fruits (83.6%). The samples' antioxidant activity (CUPRAC) was reduced by 25%. LE demonstrated antioxidant activity against human plasma oxidation and haemolysis (21.8%), but digestion mitigated these activities. FE diminished haemolysis (47.0%) and presented cytotoxicity (IC50 = 1086 µg/mL) to HUVEC cells, but these properties were lost following digestion. Ultimately, digestion partially degraded the samples' bioactive compounds, diminishing their cellular protection against oxidative stress.

Anthocyanin-rich extract from purple tea: Chemical stability, cellular antioxidant activity, and protection of human erythrocytes and plasma.

This study aimed to obtain an anthocyanin extract from the purple leaves of Camellia sinensis cv. Zijuan using a sustainable, non-toxic, and low-cost solid-liquid extraction, employing an aqueous citric acid solution (0.2 mol/L) as the extracting solvent, and to evaluate its chemical stability at different pH values, as well as its in vitro antioxidant properties in chemical and biological terms. The phenolic composition, in vitro antioxidant activity, and the stability of anthocyanins against pH, temperature, and light of the crude extract (CE) were evaluated, as well as the phenolic composition and bioactivity in the crude lyophilised extract (CLE). In the direct/reverse spectrophotometric titration, anthocyanins showed structural changes between pH 2 and 10, and reversibility of 80%. The antioxidant activity against the DPPH radical showed inhibition percentages of 73% (pH 4.5) to 39% (pH 10). Thermal stability was observed at 60 °C, and prolonged exposure of the extract to light caused photodegradation of the anthocyanins. Thirty-three phenolic compounds, including anthocyanins and catechins, were quantified in the CLE by UPLC-ESI-MS and HPLC, totalling 40.18 mg/g. CLE reduced cell viability (IC50 from 18.1 to 52.5 µg GAE/mL), exerted antiproliferative (GI50 from 0.0006 to 17.0 µg GAE/mL) and cytotoxic (LC50 from 33.2 to 89.9 µg GAE/mL) effects against A549 (human lung adenocarcinoma epithelial cells), HepG2 (hepatocellular carcinoma), HCT8 (ileocecal colorectal adenocarcinoma), and Eahy926 (somatic cell hybrid cells); and showed protection against oxidation of human plasma (635 ± 30 mg AAE/g). The results showed the diversity of compounds in the extracts and their potential for technological applications; however, temperature, pH, and light must be considered to avoid diminishing their bioactivity.

High-throughput synchronous erythrocyte cellular antioxidant activity and protection screening of phenolic-rich extracts: Protocol validation and applications.

Oxidative/nitrosative damage takes part in chronic disease development, which generates an urgent need for intervention and better therapies to manage them. The scientific community has demanded easy-to-run, cheap, and reliable methods for cellular antioxidant activity assays. This work standardised and validated an erythrocyte cellular antioxidant activity and membrane protection/injury (HERYCA-P) protocol to study food-derive extracts. The method measures intracellular reactive oxygen species (ROS) generation, lipoperoxidation, and haemolysis induced by 2,2'-azobis(2-amidinopropane) dihydrochloride. Quercetin decreased ROS generation by 50.4% and haemolysis by 2.2%, while ascorbic acid inhibited lipid peroxidation by 40.1%. Total phenolic contents of teas were correlated with decreased ROS generation (r = -0.924), lipoperoxidation (r = -0.951), and haemolysis (r = -0.869). The erythrocyte ROS generation and lipoperoxidation were also associated with CUPRAC (r = -0.925; r = -0.951) and hydroxyl radical scavenging activity (r = -0.936; r = -0.949). The precision rates of antioxidant standards and tea samples were below 15%. HERYCA-P is feasible as a complementary antioxidant assay for food matrices.

Blackcurrant press cake by-product: Increased chemical bioaccessibility and reduced antioxidant protection after in vitro simulation of gastrointestinal digestion.

This study describes the bioaccessibility in terms of total phenolic content (TPC) and antioxidant capacity before and after in vitro digestion from blackcurrant press cake extracts (BPC) and the bioactivity in cell culture, human erythrocytes as well as the in silico analysis. Chemical analysis of BPC presented an increase in TPC (270%) and anthocyanins (136%) after in vitro digestion, resulting in an improvement of antioxidant activity (DPPH 112%; FRAP: 153%). This behavior may be related to the highest activity of cyanidin-3-rutinoside, as confirmed by in silico analysis. The digested BPC did not exert cytotoxicity in cells and showed less antioxidant activity against the oxidative damage induced in endothelial cells and human erythrocytes compared to the non-digested extract. The results raise a question about the reliability we should place on results obtained only from crude samples, especially those that will be used to produce foods or nutraceuticals.

Phenolic-rich extracts from toasted white and tannin sorghum flours have distinct profiles influencing their antioxidant, antiproliferative, anti-adhesive, anti-invasive, and antimalarial activities.

Sorghum is a gluten-free cereal commonly used in foods, and its consumption has been associated with the prevention of human chronic conditions such as obesity and cancer, due to the presence of dietary fiber and phenolic compounds. This study aimed to evaluate, for the first time, the antiproliferative, antioxidant, anti-adhesion, anti-invasion, and antimalarial activities of phenolic extracts from toasted white and tannin sorghum flours to understand how different phenolic profiles contribute to sorghum biological activities. Water and 70 % ethanol/water (v/v), eco-friendly solvents, were used to obtain the phenolic extracts of toasted sorghum flours, and their phenolic profile was analyzed by UPLC-MSE. One hundred forty-five (145) phenolic compounds were identified, with 23 compounds common to all extracts. The solvent type affected the phenolic composition, with aqueous extract of both white sorghum (WSA) and tannin sorghum (TSA) containing mainly phenolic acids. White sorghum (WSE) and tannin sorghum (TSE) ethanolic extracts exhibited a higher abundance of flavonoids. WSE demonstrated the lowest IC50 on EA.hy926 (IC50 = 46.6 µg/mL) and A549 cancer cells (IC50 = 33.1 µg/mL), while TSE showed the lowest IC50 (IC50 = 70.8 µg/mL) on HCT-8 cells (human colon carcinoma). Aqueous extracts also demonstrated interesting results, similar to TSE, showing selectivity for cancer cells at higher IC50 concentrations. All sorghum extracts also reduced the adhesion and invasion of HCT-8 cells, suggesting antimetastatic potential. WSE, rich in phenolic acids and flavonoids, exhibited greater toxicity to both the W2 (chloroquine-resistant) and 3D7 (chloroquine-sensitive) strains of Plasmodium falciparum (IC50 = 8 µg GAE/mL and 22.9 µg GAE/mL, respectively). These findings underscore the potential health benefits of toasted sorghum flours, suggesting diverse applications in the food industry as a functional ingredient or even as an antioxidant supplement. Moreover, it is suggested that, besides the phenolic concentration, the phenolic profile is important to understand the health benefits of sorghum flours.

Digested galactoglucomannan mitigates oxidative stress in human cells, restores gut bacterial diversity, and provides chemopreventive protection against colon cancer in rats.

Galactoglucomannan (GGM) is the predominant hemicellulose in coniferous trees, such as Norway spruce, and has been used as a multipurpose emulsifier in the food industry. In vitro digestion with a cellular antioxidant activity assay was performed to determine the bioaccessibility and antioxidant activity of phenolic compounds, and the behaviour of GGM on in vivo experimental assay against induced colon cancer. The results showed that digestion decreased the bioaccessibility and antioxidant capacity of phenolic compounds. Cellular analysis did not support these findings once an antioxidant effect was observed in human cell lines. GGM attenuated the initiation and progression of colon cancer, by reducing the foci of aberrant crypts in rats, and modified the intestinal bacterial microbiota (disrupting the balance between Firmicutes and Bacteroidetes phyla). Thus, GGM provided chemopreventive protection against the development of colon cancer and acted as an intracellular antioxidant agent.

Green banana (Musa ssp.) mixed pulp and peel flour: A new ingredient with interesting bioactive, nutritional, and technological properties for food applications.

This study aimed to characterize and evaluate the in vitro bioactive properties of green banana pulp (GBPF), peel (GBPeF), and mixed pulp/peel flours M1 (90/10) and M2 (80/20). Lipid concentration was higher in GBPeF (7.53%), as were the levels of free and bound phenolics (577 and 653.1 mg GAE/100 g, respectively), whereas the resistant starch content was higher in GBPF (44.11%). Incorporating up to 20% GBPeF into the mixed flour had a minor effect on the starch pasting properties of GBPF. GBPeF featured rutin and trans-ferulic acid as the predominant free and bound phenolic compounds, respectively. GBPF presented different major free phenolics, though it had similar bound phenolics to GBPeF. Both M1 and M2 demonstrated a reduction in intracellular reactive oxygen species (ROS) generation. Consequently, this study validates the potential of green banana mixed flour, containing up to 20% GBPeF, for developing healthy foods and reducing post-harvest losses.

Sustainable and effective approach to recover antioxidant compounds from purple tea (Camellia sinensis var. assamica cv. Zijuan) leaves.

Camellia sinensis var. assamica cv. Zijuan (purple tea) is known for its content of anthocyanins, flavan-3-ols, and bioactivities. This study aimed to verify the influence of solvent polarity, in a solid-liquid extraction, on the content of phenolic compounds and chlorophylls, instrumental color, and antioxidant activity. Different proportions of water and ethanol (0:100, 25:75, 50:50, 75:25, and 100:0 v/v) were used for extraction. The results showed that the hydroalcoholic extract (75 % ethanol + 25 % water) had the highest contents of total flavonoids, total anthocyanins, chlorophyll A, and total carotenoids, as well as presenting the highest color intensity, proportion of yellow pigments, and antioxidant activity (total reducing capacity and scavenging of the DPPH free radical). Twenty-two compounds were identified, with chlorogenic acid, hesperidin, (-)-epicatechin, (-)-epigallocatechin gallate, and isoquercitrin being the main phenolics. This phenolic-rich extract inhibited lipoperoxidation induced in egg yolk homogenate (IC50 = 455 mg/L), showed no hemolytic behavior when human erythrocytes were subjected to osmotic stress, and exerted in vitro cytotoxic effects against cancer and hybrid cells. The extract obtained with the mixture of non-toxic solvents presented critical bioactivities, as well as a comprehensive identification of phenolic compounds in the cultivar, and has potential to be used in technological applications.

Optimization of the Green Chemistry-like Extraction of Phenolic Compounds from Grape (Vitis labrusca L.) and Blackberry (Rubus fruticosus L.) Seeds with Concomitant Biological and Antioxidant Activity Assessments.

The objective of this work was to determine the phenolic composition, chemical and cellular antioxidant activity, cytotoxicity in human cells, and peroxidative inhibition of the defatted fraction of grape (Vitis labrusca) and blackberry (Rubus fruticosus) seeds. Soxhlet extraction (Sox) was used to extract the fat and obtain the degreased material. A statistical optimization study was developed to maximize the extraction of bioactive compounds and antioxidant activity from defatted grape and blackberry seeds. Simultaneous optimization was applied with a combination of 35.9 min of extraction and a solid-to-solvent ratio of 1 g of defatted grape seed to 61.28 mL of an extracting solvent (60% ethanol) and 62.1 min of extraction and a solid-to-solvent ratio of 1 g of defatted blackberry seed to 64.1 mL of an extracting solvent (60% ethanol). In the cell viability assay, HepG2 cancer cells seemed more sensitive to grape and blackberry extracts, while Ea.hy926 hybrid cells showed more resistance to their effects. In general, the extracts presented low/no cytotoxicity, exhibited a protective effect against H2O2-induced ROS production, and demonstrated antioxidant activity and a protective effect on the erythrocytes when subjected to hypotonic and isotonic conditions not presenting hemolytic behavior (5.0 to 10.0 µg GAE/mL). Thus, the results provided a broad assessment of the bioactivity of the extracts obtained using a simple and low-cost process developed by employing non-toxic solvents and with the potential to be used in technological applications.