Publications by authors named "Janio S Santos"

Ora-pro-nobis (Pereskia aculeata Miller) is a non-conventional food plant common in Brazil. The objective of this study was to optimize the extraction of bioactive phenolic compounds from ora-pro-nobis leaves by employing solvent mixtures. Ten extracts were obtained with water, ethanol, acetone, and their binary and ternary mixtures, evaluating the chemical composition, antioxidant activity and bioactivities in vitro.

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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 L. leaves. The structures were elucidated using spectrometric methods (UV, GC-MS, NMR, and specific optical rotation).

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The chemical composition, antioxidant activity (AA), cytotoxic activity, antihemolytic effects, and enzyme inhibition (EI) of lyophilized jabuticaba (Myrciaria jaboticaba) seed extract (LJE) was studied. The main compounds found were castalagin, vescalagin, procyanidin A2, and ellagic acid. LJE was more toxic to cancer cells than to normal cells, meaning relative toxicological safety.

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Studies regarding the bioactivity of teas are mainly based on the phenolic composition and in vitro antioxidant activity of the herbal species used in their preparation. The aim of this study was to compare the in vitro and ex vivo antioxidant activity, cytotoxic/antiproliferative activity against cancer cells, the inhibitory activity of α-amylase, α-glucosidase and angiotensin I-converting enzymes, as well as the inhibition of DNA-induced fission of the peroxyl radical, in relation to aqueous extracts of Camellia sinensis var. sinensis (CS), Ilex paraguariensis (IP), Aspalathus linearis (AL) and an optimised extract (OT) containing the three herb species.

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This work aimed to investigate the phytochemical composition, nutritional value, antioxidant, antihemolytic, antihyperglycemic, and antiproliferative activities of flaxleaf fleabane (Conyza bonariensis) leaves. Different concentrations of water and ethanol (0:100, 25:75, 50:50, 75:25, and 100:0 v/v) were used in the extraction process and results showed that the hydroalcoholic extract (50:50 v/v) presented the highest total phenolics, ortho-diphenolics, Folin-Ciocalteu reducing capacity, FRAP, and Fe chelating ability values. Flaxleaf fleabane leaves (FFL) contained 19.

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In this work, different chemometric tools were compared to classify n = 26 conventional (CONV) and n = 19 organic (ORG) coffees from the main Brazilian producing regions based on the chemical composition, physicochemical properties, and antioxidant activity. Principal component analysis separated ORG and CONV coffees but the distinction among the producing regions of Brazilian coffee was not possible. Partial least squares discriminant analysis classified all ORG and CONV coffees in the external validation.

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The main objectives of the study were to compare the phenolic composition, chemical and biological antioxidant activities, and cytotoxicity towards IMR90, HCT8, and A549 cell lines of eight grades of Chinese keemun black tea (Camellia sinensis var. sinensis) using a statistical approach. No cytotoxic effects were observed on IMR90 normal cells.

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Tea is a typical processed beverage from the fresh leaves of Camellia sinensis [Camellia sinensis (L.) O. Kuntze] or Camellia assamica [Camellia sinensis var.

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This work aimed to optimize an aqueous extract rich in phenolic compounds and potential functional properties made of Ilex paraguariensis, Melissa officinalis, and Cymbopogon citratus. The lyophilized extract was used for the development of an ice cream. Total phenolics, FRAP, DPPH, Folin-Ciocalteu's reducing capacity, and total reducing capacity of different combinations of herbal extracts were tested and modeled using response surface methodology.

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Camu-camu (Myrciaria dubia) pulp, seeds, and skin are widely known because of their nutritional properties. However, the seed coat has never been studied as a source of bioactive compounds. Herein, we characterized the phenolic composition, the antioxidant activity, and inhibition of angiotensin-converting enzyme (ACE) of three different extracts (water, propanone, and ethanol) from this residue and assessed the structure-activity using bivariate and multivariate statistical approaches.

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This study aimed to optimise the experimental conditions of extraction of the phytochemical compounds and functional properties of Centaurea cyanus petals. The following parameters were determined: the chemical composition (LC-ESI-MS/MS), the effects of pH on the stability and antioxidant activity of anthocyanins, the inhibition of lipid peroxidation, antioxidant activity, anti-hemolytic activity, antimicrobial, anti-hypertensive, and cytotoxic/cytoprotective effect, and the measurements of intracellular reactive oxygen species. Results showed that the temperature and time influenced (p ≤ 0.

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In the last decade, the use of multivariate statistical techniques developed for analytical chemistry has been adopted widely in food science and technology. Usually, chemometrics is applied when there is a large and complex dataset, in terms of sample numbers, types, and responses. The results are used for authentication of geographical origin, farming systems, or even to trace adulteration of high value-added commodities.

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Article Synopsis
  • The study examined how different temperatures (45, 55, or 65°C) affect the quality of whey-based popsicles made with varying concentrations of watermelon juice.
  • It found that higher temperatures significantly reduced bioactive compounds like total phenolics, lycopene, and citrulline, which are beneficial for health.
  • Popsicles made with watermelon juice at 60°Brix and processed at 65°C had better antioxidant capacity and similar acceptance to untreated popsicles, highlighting the potential for industrial application in creating nutritious frozen treats.
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A statistical optimization study was conducted to obtain a tea containing fermented rooibos (Aspalathus linearis), white tea (Camellia sinensis var. sinensis), and roasted mate (Ilex paraguariensis). An optimal combination of these species was proposed.

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Cheese is a suitable matrix to deliver probiotic strains but it contains a high amount of sodium. The effect of partial substitution of NaCl by KCl and the addition of flavor enhancers (l-arginine, yeast and oregano extract) on probiotic Prato cheese was investigated after 1, 30, and 60 d of refrigerated storage (immediately after manufacturing, and during ripening and storage). Microbiological (lactic acid bacteria and probiotic Lactobacillus casei 01 counts and survival under gastrointestinal conditions), physicochemical (pH, proteolysis, fatty acids), bioactivity (antioxidant effect and angiotensin I-converting enzyme inhibitory activity), rheological, and water mobility by means of time domain low-field nuclear magnetic resonance were investigated.

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This work was aimed at assessing the time-temperature effects on the phenolic compounds and in vitro functional properties of aqueous extracts from red rooibos (Aspalathus linearis). The major phenolic composition (tannins, flavonoids, flavonols, ortho-diphenols, total phenolic content), antioxidant (ABTS and DPPH) and reducing capacities (FRAP and total reducing capacity), antimicrobial effects and inhibition of α-amylase/α-glucosidase were measured. Phenolic compounds were also determined by LC-ESI-MS/MS.

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The aims of the present study were to optimize and characterize the phenolic composition of a herbal extract composed of green mate (Ilex paraguariensis), clove (Syzygium aromaticum), and lemongrass (Cymbopogon citratus) and to propose the addition of this polyphenol-rich extract to fermented milks (FM) with/without sweet potato pulp (Ipomoea batatas). Proximate composition, pH, acidity, instrumental texture profile, total phenolic content (TPC), antioxidant activity (AA) of all formulations were measured, and sensory attributes were also investigated. The addition of a lyophilized extract (1g 100g) containing 87.

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Aiming to standardize the experimental protocols to assess the ability to chelate Fe(2+) and Cu(2+) using 96-well microplates, we analyzed Brazilian coffees (n=20) as a study-case in relation to their antioxidant activity using conventional methods (DPPH and FRAP assays) and correlated the results with the total phenolic content (TPC) using bivariate and multivariate statistical approaches. Complementarily, we assessed the repeatability, reproducibility, recovery, and linearity of both methods. Data showed that the proposed assays presented a good repeatability and reproducibility (<7% RSD) and mean recovery values of 96.

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Strict requirements of scientific journals allied to the need to prove the experimental data are (in)significant from the statistical standpoint have led to a steep increase in the use and development of statistical software. In this aspect, it is observed that the increasing number of software tools and packages and their wide usage has created a generation of 'click and go' users, who are eagerly destined to obtain the p-values and multivariate graphs (projection of samples and variables on the factor plane), but have no idea on how the statistical parameters are calculated and the theoretical and practical reasons he/she performed such tests. However, in this paper, some published examples are listed and discussed in detail to provide a holistic insight (positive points and limitations) about the uses and misuses of some statistical methods using different available statistical software.

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