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Context: Propolis has promising biological activities. Propolis samples from the Northeast of Bahia, Brazil – sample A from Ribeira do Pombal and B, from Tucano – were investigated, with new information regarding their biological activities. Objective: This paper describes the chemical profile, antioxidant, anti-glycation and cytotoxic activities of these propolis samples. Material and methods: Ethanol extracts of these propolis samples (EEP) and their fractions were analyzed to determine total phenolic content (TPC); antioxidant capacity through DPPH•, FRAP and lipid peroxidation; anti-glycation activity, by an in vitro glucose (10 mg/mL) bovine serum albumine (1 mg/mL) assay, during 7 d; cytotoxic activity on cancer (SF295, HCT-116, OVCAR-8, MDA-MB435, MX-1, MCF7, HL60, JURKAT, MOLT-4, K562, PC3, DU145) and normal cell lines (V79) at 0.04–25 μg/mL concentrations, for 72 h. The determination of primary phenols by ultra high-pressure liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) and volatile organic compounds content by gas chromatography-mass spectrometry (GC-MS) were also performed. Results: The EEP polar fractions exhibited up to 90% protection against lipid peroxidation. The IC50 value for anti-glycation activity of EEP was between 16.5 and 19.2 μg/mL, close to aminoguanidine (IC50 = 7.7 μg/mL). The use of UHPLC-MS/MS and GC-MS allowed the identification of 12 bioactive phenols in the EEP and 24 volatile compounds, all already reported. Conclusions: The samples present good antioxidant/anti-glycation/cytotoxic activities and a plethora of biologically active compounds. These results suggest a potential role of propolis in targeting ageing and diseases associated with oxidative and carbonylic stress, aggregating value to them.

Underutilized parts of some abundant crops can be valuable and the search for additional uses, mainly in healthy and for social purposes are very attractive. This is the case of Cocos nucifera Linn., an important source of phenolic compounds and a native plant of tropical countries, widely distributed in the Northeast and North of Brazil. The objectives of this study were to determine the phenolic chemical composition, the photoprotection capacity, represented by sun protector factor (SPF), of the ethanol extract of coconut (Cocos nucifera) husk fiber of the yellow dwarf variety (EEYD) against UVB rays and after its incorporation into sunscreen formulations. Antiglycation activity [represented by bovine serum albumin (BSA) – glucose/fructose, Collagen – glucose/fructose and BSA-Methylglyoxal (MG) assays], using aminoguanidine (AG) as a positive control, and cytotoxic effects toward macrophages, were also evaluated. The identification of non-toxic antiglycation agents holds great promise in the development of alternative therapies for diseases, such as diabetes and their complications and is not often, reported in the literature. The determination of the SPF of the EEYD together with its sunscreen formulations was performed by in vitro method. A total of seven phenolic compounds, quercetin, catechin, epicatechin, vanillic, caffeic, 4-hydroxybenzoic and chlorogenic acids were identified by high performance liquid chromatography (HPLC)-UV/Vis and ultra high performance liquid chromatography - tandem mass spectrometer UHPLC-MS/MS. The present extract (EEYD) presented photoprotective activity with SPF values equivalent to the standards, benzophenone-3 and quercetin. The formulations prepared in different concentrations of the extract (5–20 % w/w) showed maximum SPF values of 15.94. The extract presented promising antiglycation activity, higher than the positive control, the pure compound aminoguanidine (AG), except for BSA/MG, with values for BSA/glucose/fructose of 9.61 μg/mL (vs.AG 18.30 μg/mL); for collagen/glucose/fructose of 4.50 μg/mL (vs.AG 82.87 μg/mL) and 34.76 μg/mL (vs.AG,13.19 μg/mL). The present ethanol extract does not decrease macrophage viability and presents a plethora of biologically active compounds. The combined results have shown the possibility of using non-toxic EEYD, as an active ingredient in sunscreen formulations and in the nutrition/medicinal areas, giving extra value to an environmental-unfriendly residue, with strong prospects for success.

Schinus terebinthifolius Raddi is a well-known medicinal plant native of South America. This species has demonstrated important biological activities such as antihypertensive and vasodilator, antimicrobial, anti-inflammatory and antioxidant. However, no studies have been, so far, reported with the fruits of S. terebinthifolius as a protector of the placenta against Zika virus infection and as sunscreen agents. The present study aimed to investigate new uses for the ethanolic fruit extracts of S. terebinthifolius, from fruits'peel (STPE) and from the whole fruits (STWFE). Zika virus (ZIKV) has been linked to several fetal malformations, such as microcephaly and other central nervous system abnormalities. Thus, the potential of these natural extracts against ZIKV infection was evaluated, using an in vitro method. The photoprotective potential, determined by spectrometry, along with phenolic content, antioxidant capacity, and chemical composition of both extracts were also evaluated. The chemical composition of the extracts was evaluated by HPLC-UV / vis. The cytotoxicity of peel and whole fruit extracts in vero E6 cell lines, in placental cell lines and placental explant cultures were evaluated by the MTT assay. The infectivity of placental cells and explants was evaluated by qRT-PCR and the effects of extracts on ZIKV infection were investigated using HTR-8/SVneo cells, pre-treated with 100 μg mL-1 of STWFE for 1 h, and infected with MR766 (AD) or PE243 (EH) ZIKV strains. STFE and STWFE were well-tolerated by both placental-derived trophoblast cell line HTR-8/SVneo as well as by term placental chorionic villi explants, which indicate absence of cytotoxicity in all analysed concentrations. Two strains of ZIKV were tested to access if pre-treatment of trophoblast cells with the STWFE would protect them against infection. Flow cytometry analysis revealed that STWFE extract greatly reduced ZIKV infection. The extracts were also photoprotective with SPF values equivalent to the standard, benzophenone-3. The formulations prepared in different concentrations of the extracts (5-10 %) had shown maximum SPF values of 32.21. STWFE represents a potential natural mixture to be used in pregnancy in order to restrain placental infection by ZIKV and might potentially protect fetus against ZIKV-related malformations. The extracts exhibited photoprotective activity and some of the phenolic compounds, mainly resveratrol, catechin and epicatechin, are active ingredients in all assayed activities. The development of biotechnological/medical products, giving extra value to products from family farming, is expected, with strong prospects for success.

Currently, the fruit processing industry generates a high volume of waste in fruits that have not reached a quality standard for consumption or by-products generated throughout the production process. To reduce this waste, mitigating measures, such as reuse in food formulations, have been proposed. In this work the custard apple bagasse flour (Annona squamosa L.) (CAB) was produced and incorporated into cookie formulations in different proportions (5 to 50%) evaluating its acceptability. The CAB flour was characterized by physicochemical analysis, proximate composition, mineral analysis, determination of the phenolic content, and antioxidant capacity. The results of the physicochemical and proximate characterizations show that the processed flour presents values and specifications suitable for food formulations. The mineral composition of the CAB flour responds to more than 20% of the daily intake of nutrients, highlighting the Cu, Fe, Mn, Zn, Ca, and Mg. The composition of phenolic compounds for CAB flour and cookies formulations presented values ranging from 200 to 658 mg GAE/100 g, similar to flour and formulations prepared of residues tropical fruit, while DPPH• inhibition showed a variation of 9.68–10.75%. Cookies made from the CAB flour showed high acceptability making the flour promising in the nutritional incorporation in food formulations.

The adsorption process of lapachol and isolapachol sodium salts (LSS and ISS, respectively) on chitosan flakes was investigated. The aim of this work is to analyze the interaction between chitosan flakes and LSS and ISS, bioactive quinones, looking for the enhancement of their stability and for their controlled release. The effects of contact time, quinone concentration, temperature, and ionic strength on the adsorption of LSS and ISS onto chitosan flakes were studied using a batch adsorption technique. The kinetics of adsorption follows the pseudo-second-order model. Isotherm data were analyzed using the Langmuir and Freundlich models. The adsorption process was found to be endothermic for LSS–chitosan and exothermic for ISS–chitosan. The results have shown the importance of the double bond position in the side chain of the quinone. The stability of both quinones was improved after adsorption on chitosan. An increase in ionic strength decreases the amount adsorbed for both quinones around 50 % for LSS an...

Advanced glycation end products (AGEs) are generated spontaneously in cells; however, under conditions of hyperglycemia and lipid peroxidation, their levels are higher than usual, which contribute to the development of diseases such as the nonalcoholic fatty liver disease (NAFLD). NAFLD is associated with oxidative stress (OS), which is linked to the transition of steatosis to steatohepatitis due to lipid peroxidation. The AGE-receptor interaction in hepatic stellate cells leads to an increase in reactive oxygen species and enhances the proliferation and activation of these cells, worsening liver fibrosis and disease progression. In this vicious cycle, there is production of (carboxymethyl)lysine, a biomarker for products of advanced glycation and lipid peroxidation, being a shared component between the two pathways. In this review, we aim to compile evidence to support the basic molecular mechanisms of AGEs and OS generation and their influence, independently or combined, on the evolution of NAFLD. The deeper understanding of the interrelations of AGEs + OS may help to elucidate the pathogenic pathways of NAFLD and to devise rational therapeutic interventions for this disease, with an expected positive impact on quality of life of patients.

The aim of this study was to characterize the complex between mangiferin (MGN) with β-cyclodextrin (β-CD) obtained through the co-evaporation method using Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared spectroscopy (FT-IR), as well as to verify the antioxidant activity of this complex by means of radical scavenging activity toward 2,2′-diphenyl-1-picrylhydrazyl radical (RSA-DPPH ), with additional analysis of solvent effects, and Oxygen Radical Antioxidant Capacity-Fluorescein (ORAC-FL) assays. The protective effects of MGN and the MGN:β-CD complex against peroxyl radical-initiated membrane lipid peroxidation were also evaluated. The analysis of the solvent effects in the DPPH method demonstrated that at amounts of organic solvents lower than the ratio 50:50 (methanol–water or ethanol–water) there is a drawback, due to the hydrophobic nature of DPPH and should not be used. The antioxidant activity of the MGN:β-CD complex was higher than in its free form, as seen by both methods. The RSA-DPPH value was twofold larger for the complex while the ORAC-FL value was fifteenfold larger. Lipid peroxidation assays showed that the MGN:β-CD complex has a protective effect on the membrane that is as effective as the positive control (Trolox).

The present study aims to determine the antioxidant capacity of the ethanolic extracts of husk fiber of four coconut (Cocos nucifera L.) varieties (yellow dwarf, green dwarf, giant and hybrid) and to evaluate the electrochemical behavior of these extracts on a glassy carbon electrode and on a modified glassy carbon electrode. The highest values of total phenolic content were obtained for the hybrid (531 ± 24 mg GAE g -1 dry extract) and yellow dwarf (501 ± 29 mg GAE g -1 dry extract) varieties and the lowest was for the green dwarf variety with 58 ± 9 mg GAE g -1 dry extract. The ability of the extracts to scavenge DPPH• radicals was in the order of giant > yellow dwarf > hybrid > green dwarf and the IC50 values varied from 8.6 to 55.9 µg mL -1 . All varieties showed reducing potential by the use of FRAP and CUPRAC methods, with the lowest performance obtained for the green dwarf variety. Additionally, through the use of mimetic biomembranes, ethanolic extracts of coconut husk were shown to protect lipids against oxidative damage independent of the variety. The main antioxidants identified in the extract of yellow dwarf variety by UPLC-MS were quercetin and catechin. Cyclic voltammetric studies of the ethanolic extracts on glassy carbon electrode confirmed the presence of easily oxidized compounds, and the high antioxidant capacity of the varieties. This capacity was expressed as mg quercetin equivalents g -1 dry extract and ranged from 25.9 up to 53.5 mg QE g -1 . A poly-xanthurenic acid (poly-Xa)/ multi-walled carbon nanotube (MWCNT) / glassy carbon modified electrode (poly-Xa/MWCNT/GCE) was used for this purpose. Our findings suggest that these extracts are potentially important antioxidant supplements for the everyday human diet, pharmaceutical and cosmetic industries, thereby aggregating value to the enormous amount of waste from the coconut industry, mostly used for burning purposes.

The aim of this work was to evaluate floral origin, physicochemical quality and antioxidant capacity of 15 honey samples, from a semi-arid region in the northeast of Brazil and to correlate data with color and total phenolic content (TPC). A predominance of amber color was observed. The majority of samples were classified as polifloral and only two samples (the light yellow ones) were monofloral. TPC values ranged from 27.0 to 92.7 mg GAE 100 g -1 of honey, being higher in darker samples. All samples had ability to scavenge DPPH  radicals and showed reducing potential analyzed by FRAP and CUPRAC methods, with the highest performance obtained in darker samples. TPC shows good positive correlations (p

Ethanol extracts of powdered genipap ( Genipa americana L.), umbu ( Spondia tuberosa A.) and siriguela ( Spondia purpurea L.) prepared from separate pulp, seeds and peel were investigated for their (i) antioxidant capacity, which was evaluated by various known methods; (ii) acetylcholinesterase (AChE) inhibitory activity; and (iii) cytotoxic effect on corneal epithelial cells of sheep. The highest values of total phenolic content were obtained with peel and seed extracts. Siriguela and umbu (seeds and peel) extracts displayed the highest antioxidant activities. Lipid peroxidation assays using mimetic biomembranes and mouse liver homogenates indicated that genipap pulp is a promising antioxidant. The investigation of phenols and organic acid contents revealed the presence of quercetin, citric and quinic acids, chlorogenic acid derivatives, among others, in several extracts, with the highest amount found in siriguela seeds. Genipap pulp and siriguela seed ethanol extracts presented an AChE inhibition zone similar to that of the positive control, carbachol. AChE inhibition assay with chlorogenic acid, one of the main constituents of siriguela seeds, revealed that this acid showed activity similar to that of the control physostigmine. These data suggest that these extracts are potentially important antioxidant supplements for the everyday human diet, pharmaceutical and cosmetic industries.

Methanolic extract powders of acerola, passion fruit and pineapple industrial residues, including pulp, seeds and peel, altogether (except for acerola) devoid of seeds, were screened for antioxidant capacity. The total phenolic contents (TPCs) of the extract powders were compared with their radical-scavenging activities (RSA) against both DPPH • and superoxide anion ( O 2 • - ) radicals, and their protective effect against liposome peroxidation, triggered by peroxyl radical. Lipid peroxidation was followed by the fluorescence decay of the probe, 4,4-difluoro-5-(4-phenyl-1,3-butadienyl)-4-bora-3a,4a-diaza-s-indacene-3-undecanoic acid (C11-BODIPY581/591). The TPCs of acerola, passion fruit and pineapple extract powders were (94.6 ± 7.4); (41.2 ± 4.2) and (9.1 ± 1.3) mg of gallic acid equivalents g−1 of dry extract, respectively. Acerola showed the best RSA- DPPH • scores, whereas passion fruit was more protective on the RSA- O 2 • - system. Together with the protective effects against lipid peroxidation (rate of BODIPY decay), which were similar for acerola and passion fruit extracts, these data suggest that the methanolic extracts of acerola and passion fruit residues may be useful as antioxidant supplements, particularly the acerola extract, due to its high phenolic content.

Growing knowledge on the health-promoting impact of antioxidants in everyday foods, combined with the assumption that a number of common synthetic preservatives may have hazardous side effects has led to increased investigations in the field of natural antioxidants, principally those found in plants. Food industries normally discard plant residues that could benefit the human health and diminish undesirable environmental impact. Once estimated the content of antioxidants in these residues, advantageous economical and social alternatives to the discard are possible, for example, their use for preparation of nutraceuticals to be offered to low-income populations. We present here a broad, although not complete, account of the continuously growing knowledge on the antioxidant capacity of whole fruits, seeds and peels, cereals, vegetal oils and aromatic plants, at several physical forms, as well as a description of the usual methods for evaluating their antioxidant capacity and examples of agroindustrial processes that could be harnessed for the production of antioxidant supplement food, along with research perspectives in the area.

It is known that Brazilian chrysotile is rapidly removed from the lungs, but quantitative studies about the influence of lung surfactants on chrysotile dissolution have not been investigated. In this work, the chemical behavior of chrysotile and its dissolution in the presence of dipalmitoylphosphatidylcholine (DPPC) were investigated in physiological conditions. The dissolution was investigated through quantification of magnesium and silicon released by chrysotile. At 37 degrees C, the magnesium concentration is similar to control (without DPPC), which is about 2.0x10(-4)molL(-1), meaning that the dissolution process is not affected by the presence of this surfactant. The same was observed for silicon. The silicon concentration released by chrysotile is similar in all media tested. It is known that the dissolution mechanisms of brucite and tridymite layers are different. From our results, we propose that under physiological conditions, the mechanism of brucite dissolution is based on its interaction with hydrogen ions and that the mechanism of tridymite dissolution is based on a hydrolysis process.

Summary In the present work, we optimised the glycerol + caproic acid/enantic acid/caprylic acid esterification conditions, using chemical routes, in order to get tricaproin, trienantin and tricaprylin in a medium solely composed of reagents. The option for cleaner conditions, without catalyst and solvent was preferred. The best conditions for tricaprylin and trienantin chemical synthesis were 6 h of contact, with a temperature around 160 ± 5 °C, followed by a 20 h of contact using higher temperatures (around 200 ± 5 °C). The volatility of caproic acid impeded the prolonged use of higher temperatures and this limited the yield of tricaproin that could be obtained. The synthesis of these triacylglycerols in the absence of both solvent and catalyst is of importance in consideration of the possible nutritional use of the products so formed.

This study aims to evaluate the effects of diets deficient in choline and/or cystine on hepatocellular injury in animal models (young male Wistar rats, aged 21 days), by monitoring some of the oxidative stress biomarkers and the expression of RAGE, TNF-α, and IL-1β. The animals were divided into 6 groups (n=10) and submitted to different diets over 30 days: AIN-93 diet (standard, St), AIN-93 choline deficient (CD) diet and AIN-93 choline and cystine deficient (CCD) diet, in the pellet (pl) and powder (pw) diet forms. Independently of the diet form, AIN-93 diet already led to hepatic steatosis and CD/CCD diets provoked hepatic damage. The increase of lipid peroxidation, represented by the evaluation of thiobarbituric acid reactive species, associated with the decrease of levels of antioxidant enzymes, were the parameters with higher significance toward redox profile in this model of hepatic injury. Regarding inflammation, in relation to TNF-α, higher levels were evidenced inCD(pl), while, for IL-1β, no significant alteration was detected. RAGE expression was practically the same in all groups, with exception ofCCD(pw)versusCCD(pl). These results together confirm that AIN-93 causes hepatic steatosis and choline and/or cysteine deficiencies produce important hepatic injury associated with oxidative stress and inflammatory profiles.

Adsorption of sodium dodecylsulfate (SDS) onto chrysotile from aqueous solutions was investigated along with varying temperature, ionic strength and surface treatments. Commercial chrysotile fibers were treated by sonication or extensive washings. The ratio of adsorbed SDS per gram of chrysotile is approximately constant with varying chrysotile masses. A steady state is reached after about 2 h of contact between SDS and chrysotile. In general, less surfactant is adsorbed on the sonicated chrysotile than on the extensively washed chrysotile. For the sonicated chrysotile, isotherms presented an adsorption maximum in the region of the surfactant critical micelle concentration, when the experiments were carried out without ionic strength control. The adsorption maximum is due to the presence of magnesium ions in the solution, which can form complexes with dodecylsulfate ions. For the extensively washed chrysotile, the isotherm behavior is similar to that obtained with sonicated chrysotile in the presence of an inert electrolyte. No significant difference in adsorption of SDS on the extensively washed chrysotile was observed when varying temperature or ionic strength. The adsorption of SDS was found to be dependent on the prior surface treatment.

Os estudos sobre adsorção do herbicida trifluralina (TRF) em quitosana foram realizados em batelada, usando temperaturas entre 298 e 313 K. Os resultados de adsorção ajustaram-se perfeitamente ao modelo de adsorção de Langmuir. O valor de entalpia obtido -10,2 ± 0,8 kJ mol-1 confirma que a interação TRF-quitosana é exotérmica e que o processo de adsorção é relativo à interação eletrostática entre o grupo amônio da quitosana e o dipolo negativo dos grupos substituintes de TRF, sendo dependente da força iônica. Estudos voltamétricos mostraram que TRF apresentou dois picos de redução em eletrodo de CV, ambos de natureza difusional e irreversível, referentes à redução dos grupos nitroaromáticos. A corrente do primeiro pico de redução intensificou-se no eletrodo de carbono vítreo modificado com quitosana, em comparação com o eletrodo não modificado. Isto foi atribuído à adsorção/acumulação de TRF em quitosana. A corrente de redução em voltametria de pulso diferencial foi proporcional à concentração de TRF na faixa de 2,49 × 10-7 a 5,79 × 10-6 mol L-1, com limite de detecção de 7,45 × 10-8 mol L-1._______________________________________________________________________________ ABSTRACT: The studies about adsorption of the herbicide trifluralin (TRF), on chitosan, were carried out by batch methods using temperatures from 298 up to 313 K. The adsorption results were well fitted to Langmuir adsorption model. The obtained enthalpic value of -10.2 ± 0.8 kJ mol-1 confirms that the TRF-chitosan interaction is exothermic and that the adsorption process is relative to electrostatic interaction between the ammonium group of chitosan and the negative dipole of the substituent groups of TRF, being dependent on ionic strength. Voltammetric studies showed that TRF exhibited two irreversible, diffusional reduction waves related to the reduction of the nitroaromatic groups. The current of the first reduction peak intensified on the chitosan-modified glassy carbon electrode in comparison with the unmodified one. This was attributed to the adsorption/accumulation of TRF on chitosan. The reduction current, using Differential Pulse Voltammetry, was proportional to the concentration of TRF in the range of 2.49 ×10-7 to 5.79 ×10-6 mol L-1, with a detection limit of 7.45 × 10-8 mol L-1.