Radical Scavenging Capacity Assay Research Articles

Garlic peel extract as an antioxidant inhibits triple‐negative breast tumor growth and angiogenesis by inhibiting cyclooxygenase‐2 expression

AbstractGarlic peels are frequently disposed of as agro‐waste; their bioactivity and physiological activity for health benefits and disease protection are neglected. This study aims to examine the potential inhibitory effects of garlic peel extract as an antioxidant on 4 T1 triple‐negative breast cancer (TNBC) tumors in mice. The bioactive constituents of garlic peel were identified through HPLC‐MS/MS analysis, while the antioxidant properties of garlic peel extract were assessed using peroxyl radical scavenging capacity (PSC) and cellular antioxidant activity (CAA) assays. Subsequently, the inhibitory effects of garlic peel extract on 4T1 tumor growth were evaluated using a 4T1 model. The results showed that 433 polyphenol compounds were found in garlic peel extract; among them, flavonoids and phenolic acid are the primary polyphenols with natural antioxidant activity, and both high and low concentrations of the extract exhibited tumor‐suppressive effects. Immunohistochemistry was employed to assess the expression levels of COX‐2, CD31, VEGFA, MMP2, and MMP9 in tumor tissues in order to investigate the antioxidant properties of garlic peel extract, specifically its ability to suppress COX‐2 expression. The findings of this study offer a foundation for the advancement of garlic peel‐based functional products and contribute to the identification of potential anti‐cancer agents and therapeutic targets.

Garlic peel extract as an antioxidant inhibits triple‐negative breast tumor growth and angiogenesis by inhibiting cyclooxygenase‐2 expression

AbstractGarlic peels are frequently disposed of as agro‐waste; their bioactivity and physiological activity for health benefits and disease protection are neglected. This study aims to examine the potential inhibitory effects of garlic peel extract as an antioxidant on 4 T1 triple‐negative breast cancer (TNBC) tumors in mice. The bioactive constituents of garlic peel were identified through HPLC‐MS/MS analysis, while the antioxidant properties of garlic peel extract were assessed using peroxyl radical scavenging capacity (PSC) and cellular antioxidant activity (CAA) assays. Subsequently, the inhibitory effects of garlic peel extract on 4T1 tumor growth were evaluated using a 4T1 model. The results showed that 433 polyphenol compounds were found in garlic peel extract; among them, flavonoids and phenolic acid are the primary polyphenols with natural antioxidant activity, and both high and low concentrations of the extract exhibited tumor‐suppressive effects. Immunohistochemistry was employed to assess the expression levels of COX‐2, CD31, VEGFA, MMP2, and MMP9 in tumor tissues in order to investigate the antioxidant properties of garlic peel extract, specifically its ability to suppress COX‐2 expression. The findings of this study offer a foundation for the advancement of garlic peel‐based functional products and contribute to the identification of potential anti‐cancer agents and therapeutic targets.

Exploring the multifaceted bioactivities of Lavandula pinnata L. essential oil: promising pharmacological activities.

Introduction: This study investigates the biological activities of Lavandula pinnata essential oil (LPEO), an endemic lavender species from the Canary Islands, traditionally used in treating various ailments. Methods: LPEO was extracted by hydrodistillation and analyzed using GC-MS. Antioxidant activity was assessed by DPPH radical scavenging and total antioxidant capacity assays. Antimicrobial activity was evaluated by disc diffusion, MIC, MBC, and MFC determination against bacterial (Staphylococcus aureus, Micrococcus luteus, Escherichia coli, Pseudomonas aeruginosa) and fungal (Candida glabrata, Rhodotorula glutinis, Aspergillus niger, Penicillium digitatum) strains. Antidiabetic and anti-gout potential were investigated through α-amylase, α-glucosidase, and xanthine oxidase inhibition assays. Antityrosinase activity was determined using a modified dopachrome method. Cytotoxicity was assessed by MTT assay against breast (MCF-7, MDA-MB-468), liver (HepG2), colon (HCT-15) cancer cells, and normal cells (PBMCs). Results and discussion: LPEO exhibits potent antiradical activity (IC50 = 148.33 ± 2.48μg/mL) and significant antioxidant capacity (TAC = 171.56 ± 2.34μg AA/mg of EO). It demonstrates notable antibacterial activity against four strains (Staphylococcus aureus, Micrococcus luteus, Escherichia coli, and Pseudomonas aeruginosa) with inhibition zones ranging from 18.70 ± 0.30mm to 29.20 ± 0.30mm, along with relatively low MIC and MBC values. LPEO displays significant antifungal activity against four strains (Candida glabrata, Rhodotorula glutinis, Aspergillus niger, and Penicillium digitatum) with a fungicidal effect at 1mg/mL, surpassing the positive control (cycloheximide), and MIC and MFC values indicating a fungicidal effect. It exhibits substantial inhibition of xanthine oxidase enzyme (IC50 = 26.48 ± 0.90μg/mL), comparable to allopurinol, and marked inhibitory effects on α-amylase (IC50 = 31.56 ± 0.46μg/mL) and α-glucosidase (IC50 = 58.47 ± 2.35μg/mL) enzymes.The enzyme tyrosinase is inhibited by LPEO (IC50 = 29.11 ± 0.08mg/mL). LPEO displays moderate cytotoxic activity against breast, liver, and colon cancer cells, with low toxicity towards normal cells (PBMC). LPEO exhibits greater selectivity than cisplatin for breast (MCF-7) and colon (HCT-15) cancer cells but lower selectivity for liver (HepG2) and metastatic breast (MDA-MB-468) cancer cells. These findings suggest the potential of LPEO as an antioxidant, antimicrobial, anti-gout, antidiabetic, and anticancer agent.

Influence of Nutrient Deprivation on the Antioxidant Capacity and Chemical Profile of Two Diatoms from Genus Chaetoceros.

The limited availability of phosphate, nitrogen and silicon in the growth media affects the growth, cellular processes, and metabolism of diatoms. Silicon deficiency primarily affects diatom morphology, while phosphate deficiency reduces the production of nucleic acids and phospholipids. Differences in pigment and protein composition are mainly due to nitrogen deficiency. In this study, Chaetoceros socialis and Chaetoceros costatus were cultured under phosphate, nitrogen, and silicon deprivation conditions. The diatom biomass was collected during the stationary growth phase and extracted with 70% ethanol under ultrasonication. The chemical profiles of the extracts were analyzed by high-performance liquid chromatography with high-resolution mass spectrometry with electrospray ionisation (UHPLC-ESI-HRMS), while the antioxidant capacity was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and oxygen radical absorbance capacity (ORAC) assays. Pigments, fatty acids, sterols, and derivatives were detected in both species. The total phenolic content in the extracts ranged from 46.25 ± 1.08 to 89.38 ± 6.21 mg of gallic acid equivalent (GAE)/L and from 29.58 ± 1.08 to 54.17 ± 1.18 mg GAE/L. for C. costatus and C. socialis, respectively. Antioxidant activity was higher in C. costatus extracts, especially those obtained from nitrogen-deprived media. The results of this study contribute to the existing knowledge and the ongoing efforts to overcome application and commercialization barriers of microalgae for wide-ranging potential in different industries.

Comparative Analysis of Physiochemical Properties and In Vitro Antioxidant Potency Among Morphotypes of Centella asiatica Grown in Sri Lanka

Centella asiatica commonly referred as Gotukola, is recognized for its extensive application in traditional medicine owing to its remarkable health benefits. This study investigated the differences in pH, ash content, moisture content, and in vitro antioxidant potential among three prevalent vine- type morphotypes of C. asiatica: Wel Gotukola, Meerigima Gotukola, and Yodha Gotukola, indigenous to Sri Lanka. C. asiatica plants of the same age (100 days) at their first harvestable matured stage, were randomly collected from domestic gardens in Gampaha District, Sri Lanka. Three replicates of each morphotype were sampled. Moisture and ash content were analysed using the standard AOAC method, and pH was measured using the potentiometric method. DPPH (2,2- Diphenyl-1-picrylhydrazyl) radical scavenging capacity assay was used to determine the antioxidant activity. To thoroughly compare antioxidant potential among morphotypes, the ANOVA test was utilized followed by post-hoc Tukey HSD tests. Following results were obtained for the average moisture content of Wel Gotukola (83.41%±1.16%), Yodha Gotukola (74.33%±2.23%), and Meerigama Gotukola (79.46%±1.89%), alongside average ash content of Wel Gotukola (11.60%±1.02%), Yodha Gotukola (13.12%±2.57%), and Meerigama Gotukola (12.17%±2.01%). Additionally, an average pH of Wel Gotukola (6.00±0.21), Yodha Gotukola (5.75±0.25), and Meerigama Gotukola (5.98±0.14) was observed. The antioxidant activity of C. asiatica extracts exhibited concentration dependent increases in radical scavenging capacity. Notably, the DPPH radical scavenging potency, denoted by the minimum IC50 value, exhibited significant variations across different Gotukola varieties (p<0.05): Wel Gotukola (6.4 ± 0.54 µg/mL), Yodha Gotukola (8.56±0.35 µg/mL), and Meerigama Gotukola (7.0±0.75 µg/mL). Post-hoc Tukey tests showed antioxidant activity was significantly higher in Wel Gotukola compared to that of Meerigama and Yodha Gotukola morphotypes (p<0.05). Furthermore, Wel Gotukola demonstrated the highest average pH, moisture content, and the lowest mineral content. Conversely, Yodha Gotukola exhibited the lowest pH, moisture content, and the highest ash content. These findings underscore the potential of chemical parameters in elucidating the distinctive attributes of the three Gotukola varieties. Specifically, the significantly higher antioxidant potential observed in Wel Gotukola suggests its potential as an optimal candidate for herbal product development. This study imparts valuable insights into optimizing the therapeutic efficacy of formulations based on the specific C. asiatica employed in such endeavours.
 
 Keywords: Antioxidant activity, Centella asiatica, Morphotypes, Proximate analysis

Flours from Spondias mombin and Spondias tuberosa seeds: Physicochemical characterization, technological properties, and antioxidant, antibacterial, and antidiabetic activities.

Yellow mombin (Spondias mombin) and Brazil plum (Spondias tuberosa) seeds are byproducts of exploiting their pulp and currently have no relevant food or industrial applications. Thus, the present study aimed to evaluate the physicochemical, technological, and functional characteristics of flours obtained from yellow mombin (YMF) and Brazil plum (BPF) residues. The flours presented a high percentage of insoluble fiber (68.8-70.2g/100g) and low carbohydrate (2.7-4.0g/100g) and caloric (91.9-95.3kcal) values. The flours showed potential for technological application. In addition, the highest concentration of total phenolic content (31.1-50.2mgGAE/g) was obtained with 70% acetone, which provided excellent results for antioxidant capacity evaluated by 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (81.0%-89.7%) and 2,2-diphenyl-1-picrylhydrazyl (60.6%-69.1%) radical scavenging capacity assays. Flour extracts in 70% acetone also exhibited inhibition of α-amylase (63.3%-78.8%) and amyloglucosidase (63.5%-71.0%). The antibacterial study revealed that extracts inhibited the growth of Escherichia coli, Burkholderia cepacia, and Burkholderia multivorans. Therefore, this study suggests the use of yellow mombin and Brazil plum residues for different food or industrial applications. PRACTICAL APPLICATION: The knowledge gained from this study will open a new approach to add value to yellow mombin and Brazil plum fruit seeds as sources of fiber and bioactive compounds, with promising application in the formulation of functional and nutraceutical products, benefiting both a sustainable environment and a sustainable industry.

Application of response surface methodology in the characterization and sensorial analysis of Anacardium humile liqueur

Anacardium humile, known as “cajuzinho-do-cerrado,” is a native Brazilian Cerrado fruit similar to the cashew but less studied, particularly its phenolic compound content and profile. This study used a factorial design to examine how A. humile concentration and maturation time affect the liqueur's physicochemical attributes, phenolic content, antioxidant capacity, and sensory appeal. The liqueurs exhibited low antioxidant capacities as determined by the 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity assay (DPPH), ferric ion reducing antioxidant power (FRAP), and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid). This is likely attributable to a reduction in phenolic compounds within the liqueurs compared to A. humile. The phenolic compound profile of A. humile showed 11 compounds, comprising 5 flavonols, 3 hydroxycinnamic acids, and 2 hydrolyzable tannins. Treatment 8 (500 g of A. humile and 17 days of maturation) showed the highest value for phenolic compound content. However, with regard to sensory analysis, this was the darkest liqueur and the least accepted test, while Treatment 5 (147.5 g of A. humile and 10 days of maturation) was one of the most accepted and chosen as the best liqueur due to the highest antioxidant capacity by FRAP and DPPH methods. The fusion of technology and factorial design proved efficacious in formulating functional liqueurs.

New triazole-based Schiff base ligands and their Co(II) and Ni(II) complexes as biological potent molecules: Chemical preparation, structural elucidation and biological studies

Preparation of sequence of Co(II) and Ni(II) metal complexes (C1a- C3a and C1b- C3b) of bidentate ligands (L1- L3) has been resulted from the condensation of substituted 1,2,4-triazole with various substituted 1,3-diphenyl-1H-pyrazole-4-carbaldehyde are described in the present study. The structures of synthesized complexes were established by elemental investigation, IR, mass spectroscopy and TGA examinations. The data confirmed that bonding through the nitrogen atom from imine group and sulfur atom of triazole, ligand get integrated with the metal ions in a bidentate nature, gave an octahedral geometry to the complexes. The antibacterial activities have been tested against S. aureus Gram-positive bacteria and E. coli Gram-negative bacteria. Further, through DPPH radical scavenging capacity assay the antioxidant activity values were quantified; all the compounds demonstrate outstanding antioxidant activities. Using molecular docking and highest binding affinities for biological targets, the ligand and complex interactions have been studied. The in vitro anti-proliferative nature of synthesized ligands and their Ni(II) and Co(II) complexes were appraised with the help of SRB assay against Human hepato carcinoma cell (Hep-G2), Lung cells (A-549), Breast cell (MCF-7), Prostate cell (PC-3). Anti-tubercular studies revealed that the complex demonstrates a greater anti-tubercular activity than the analogous ligands.

Polysaccharides from red seaweeds: Effect of extraction methods on physicochemical characteristics and antioxidant activities

Seaweed polysaccharides are reported to possess biological and medicinal properties. Specifically, the antioxidant activity of seaweed extracts is the subject of intensive research due to ever-increasing demands from the food and pharmaceutical industries. The structure and composition of polysaccharides (carrageenan, xylan) extracted from four red seaweed species: Chondrus crispus (CC), Ahnfeltiopsis devoniensis (AD), Sarcodiotheca gaudichaudii (SG) and Palmaria palmata (PP) were compared and correlated with their antioxidant activity. Crude polysaccharide extracts were characterized by NMR (1H and 13C), HPLC-SEC, and FTIR spectroscopy. Total phenolic content (TPC), total sugars, sulfate and protein content were determined using spectrophotometric methods. The antioxidant capacity of each fractionated polysaccharide sample was evaluated by the following methods: DPPH (2,2-diphenyl-1-picrylhydrazyl radical), ABTS (2,2-azino-bis-[3-ethylbenzothiazoline-6-sulfonic acid]), superoxide dismutase (SOD), ferric-reducing power in FRAP (Ferric-reducing Antioxidant Power) assays, and the hydroxyl radical (OH) scavenging capacity assay. The highest antioxidant activity was found in extracts from A. devoniensis (ι/κ hybrid carrageenan), while the lowest was in P. palmata (xylans). Moreover, Chondrus crispus extracts did not possess SOD inhibition activity. Polysaccharides evaluated in this study offer high potential for applications in the food, pharmaceutical and biotechnology industries.

Phytochemical profiles, antioxidant activities, and synergistic antiproliferative effects of blueberry and apple peel extracts.

Blueberries and apples exhibit favorable bioactivity and health benefits due to their rich phytochemicals. Natural phytochemicals exist in complex forms, but there are few reports on whether have additive, synergistic or antagonistic effects between different phytochemicals. The aim of the present investigation was to elucidate the synergistic effects of blueberry extract (BE) and apple peel extract (APE) together in inhibiting the proliferation of HepG2 liver cancer cells. Meanwhile, phytochemical characterization of BE and APE were detected by HPLC, and total antioxidant activity was determined via cellular antioxidant activity (CAA) assay, oxygen radical absorption capacity (ORAC) assay and peroxy radical scavenging capacity (PSC) assay. The results showed that BE and APE were rich in phytochemicals and had potent antioxidant activities, which synergistically inhibited cell proliferation. In the bilateral combination, the dose reduction index (DRI) value increased 2-fold, and the combination index (CI) value at 95% inhibition was less than 1. Additionally, BE+APE supplementation could promote the expression levels of p53 and c-myc genes. In conclusion, the BE and APE had strong antioxidant activity and exhibited synergistic inhibition against HepG2 cells proliferation. This can provide a theoretical basis for the synergistic effect of different phytochemicals in health care. This article is protected by copyright. All rights reserved.

In Vitro Assessment of the Antioxidant and Anticancer Properties of Flammulina velutipes Stipe Extracts.

Flammulina velutipes (FV), also known as the golden needle mushroom, is an edible and medicinal fungus that contains bioactive substances regulating various physiological functions. While the fruiting bodies of FV are commonly consumed, their stipes are often discarded despite containing polysaccharides. In this study, the biological functions of FV stipes (FV-S) were investigated to reduce waste and pollution while increasing their value. The antioxidant activity of FV was evaluated using three methods: the DPPH radical-scavenging capacity assay, ferrous ion chelating assay, and reducing power analysis. The anti-cancer potential was assessed through MTT viability and immunoblotting analyses. Results showed that FV-S had higher polysaccharide and total phenolic contents and greater antioxidant abilities, particularly in ethanolic extracts. FV-S also exhibited significant anticancer properties, specifically in hot water extracts with high polysaccharide contents, and suppressed prostate cancer cell viability by inhibiting androgen receptor and PCa-specific antigen mRNA expression while inducing caspase-3/7 activation. FV-S is rich in bioactive components, possesses higher antioxidant and anticancer abilities, and has potential as an anticancer agent, which could enhance the value of FV.

Botanical Origins and Antioxidant Activities of Two Types of Flavonoid-Rich Poplar-Type Propolis.

(1) Background: Propolis has attracted attention in recent years due to its important pharmacological effects. The present study aimed to investigate the botanical origins of 39 propolis samples and evaluate their antioxidant activities; (2) Methods: A HPLC-PDA system was used to analyze the phenolic compositions of propolis and poplar bud resin samples. The antioxidant activities of propolis samples were evaluated by oxygen radical absorption capacity (ORAC) and superoxide anion free radical scavenging capacity assay; (3) Results: Our study shows that 17 propolis samples were characterized by five predominant flavonoids, including 5-methoxy pinobanksin, pinobanksin, pinocembrin, pinobanksin-3-acetate, and chrysin, while 22 propolis samples were characterized by four flavonoids (pinobanksin, pinocembrin, pinobanksin-3-acetate, and chrysin). The average contents of characteristic flavonoids reached up to over 70% and 65% of total phenolics, respectively. Furthermore, the botanical origins of the two types of propolis samples were identified as Populus × euramericana cv. 'Neva' and Populus Simonii × P. nigra, respectively; (4) Conclusions: Most notably, our results reveal that these propolis samples presented excellent antioxidant activities due to their high contents of flavonoid. These flavonoid-rich propolis samples can thus be used to develop low-allergen and high-antioxidant nutraceuticals.

Assessing radical scavenging capacity of Sempervivum tectorum L. leaf extracts: An integrated high-performance thin-layer chromatography/in silico/chemometrics approach

High-Performance Thin-Layer Chromatography (HPTLC)-radical scavenging capacity (RSC) assays are standard techniques for the separation and identification of antioxidants from complex mixtures. HPTLC coupled with DPPH· visualization of chromatograms allows for the detection of individual antioxidants. However, other HPTLC-RSC assays that recognize compounds exhibiting different mechanisms of radical-scavenging activity are rarely reported. In this study, we developed an integrated approach that combines five HPTLC-RSC assays, principal component analysis (PCA) and quantum chemical calculations to assess the antioxidant capacity of Sempervivum tectorum L. leaf extracts. Two HPTLC assays - potassium hexacyanoferrate(III) total reducing power assay (TRP) and total antioxidant capacity by phosphomolybdenum method (TAC) - were developed for the first time. The method supports a more in-depth study of the RSC of natural products, as it compares the radical scavenging fingerprints of S. tectorum leaf extracts and recognizes differences in their individual bioactive constituents. Kaempferol, kaempferol 3-O-glucoside, quercetin 3-O-glucoside, caffeic acid, and gallic acid were identified as the compounds that discriminate HPTLC-RSC assays according to their mechanism of action and capture the similarities between 20 S. tectorum samples. Additionally, DFT calculations on M06–2X/6–31+G(d,p) level were applied to map thermodynamic feasibility of hydrogen atom transfer (HAT) and single electron transfer (SET) mechanisms of the identified compounds. Based on experimental and theoretical results, a combination of HPTLC-ABTS and HPTLC-TAC assays were proposed as the optimal method for mapping the antioxidants from S. tectorum. This study represents a step forward in identifying and quantifying individual antioxidants from complex food and natural product matrices in a more rational manner.

Phytochemical Screening, Antioxidant Activity and α‐Glucosidase Inhibitability of Bauhinia  blakeana Dunn Leaf and Flower Extracts from Vietnam

Bauhinia  blakeana Dunn is traditionally used as vegetables, medicinal herbs to treat diseases, and ornamental trees. The current study was performed to evaluate the phytochemicals, total phenolic (TPC) and total flavonoid (TFC) contents, antioxidant activity, and α‐glucosidase inhibitability of Bblakeana leaf and flower from Vietnam. Qualitative phytochemical analysis showed positive results for carbohydrates, organic acids, carotenoids, steroids, cardiac glycosides, triterpenoids, saponins, flavonoids, and tannins. The TPC and TFC obtained from B blakeana leaf were 99.81 ± 0.94 (mg GAE/g E) and 114.93 ± 1.06 (mg RE/g E), respectively, whereas they were 40.45 ± 0.50 (mg GAE/g E) and 59.61 ± 0.85 (mg RE/g E) from B blakeana The DPPH radical scavenging capacity assay of the crude ethanolic extracts of B blakeana leaf (IC50 = 266.52 ± 1.03 μg/mL; R2 = 0.9864) and flower (IC50 > 1000 μg/mL) was determined. The leaf and flower extracts showed significant α-glucosidase inhibitory activity with IC50 values of 61.88 ± 0.19 μg/mL (R2 = 0.9838), 190.79 ± 0.18μg/mL (R2 = 0.9891), respectively. These results indicated that the extract of B blakeana leaf and flower can be a promising candidate for alternative drug or functional food discovery, and nutritional recommendations for the control of oxidative stress and diabetes.

Supercritical fluid extraction of torch ginger: Encapsulation, metabolite profiling, and antioxidant activity

ObjectivesThe objective of this study was first to perform the supercritical fluid extraction (SFE) and encapsulationof torch ginger (Etlingera elatior) inflorescences into a functional powder. Second objective was to evaluate the powder’s characteristics, metabolite profiles, and antioxidant activity. MethodsTorch ginger inflorescences were extracted via SFE technique, and the obtained extract was encapsulated by a spray-drying process with maltodextrin as an encapsulating agent. Subsequently, the powder was evaluated for its physical characteristics, determination of metabolite profiles by using a Fourier Transform Infrared Spectrophotometer (FTIR) and Gas Chromatography-Mass Spectrometry (GC–MS), and antioxidant activity. ResultsSpray drying encapsulation process managed to yield around 59.8% of torch ginger extract powder (TGEP) by using 10% of extract, which the obtained yield was twice higher than in another study. TGEP showed inconsistent agglomeration behaviour in particle size examination with distinct sizes concentrating at 2.2 μm and 17.4 μm, respectively. Brunauer-Emmett-Teller (BET) analysis of TGEP unveiled a considerably high surface area (1.13 m2/g), pore volume (0.218 cm3/g), and pore size (384.6 nm). The metabolites profile of TGEP was studied and characterized using two spectroscopic analyses. Analysis by the FTIR showed the presence of O–H, C–H, C = C, C = O, CO-O-CO, C-N, and C-O functional groups in the sample. Subsequently, the result of the GC–MS characterization revealed about 59 metabolites that predominantly fatty acids (30.5%), terpenes and derivatives (20.3%), fatty acid esters (16.9%), and alcohols (8.47%) were present in TGEP. The powder also demonstrated a high antioxidant activity based on the evaluation of its total phenolic content (23.3 ± 0.662 mg GAE/g TGEP), EC50 as determined from 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity assay (1.31 ± 0.002 mg/mL), and ferric reducing antioxidant power (2919.5 ± 19.9 μM TE/g TGEP), which were better than previous studies. ConclusionTherefore, this study unveiled TGEP as a functional powder with a high content of bioactive compounds with excellent bioactivity.

Phytochemical Compounds, Acute Toxicity, Anti-Inflammatory and Antioxidant Activities of Thymus leptobotrys Murb Essential Oil.

The present study was conducted to evaluate the acute toxicity and anti-inflammatory effect in vivo, as well as the antioxidant activity, of the essential oil of Thymus leptobotrys Murb. The results indicate that the tested essential oil is non-toxic, with an estimated LD50 of 2500 mg kg-1 of mice body weight. The anti-inflammatory test revealed that, at a dose of 200 mg kg-1, the essential oil reduced rat paw edemas by 89.59% within 3 h of oral administration, this reduction in edema size was greater than that obtained with indomethacin (75.78%). The antioxidant activity (IC50) of Thymus leptobotrys Murb essential oil was 346.896 µg mL-1 and 861.136 mg Trolox equivalent/g essential oil in the 2.2-diphenyl1-picryl-hydrazyl radical scavenging capacity (DPPH) and Trolox equivalent antioxidant capacity (TEAC) assays, respectively. The toxicity test reveals an LD50 greater than 2500 mg kg-1 of body weight of mice which classifies it within category 5 of non-toxic substances that can be administered orally. These results suggest that the essential oil of Thymus leptobotrys Murb is not toxic, and it represents a valuable source of anti-inflammatory and antioxidant metabolites.

Antioxidant, cytotoxic, antibacterial and thrombolytic activities of Centella asiatica L.: possible role of phenolics and flavonoids

BackgroundCentella asiatica L. (Apiaceae), a green leafy vegetable, has been used as a popular folk medicine in Bangladesh in the treatment of various ailments. The plant is reported to contain phenolics and flavonoids, but their bioactive potentials are not yet completely known. The present study was designed to investigate the role of the phenolic and flavonoids in the antioxidant, cytotoxicity, antibacterial and thrombolytic activities.MethodsFour solvent fractions viz. methanol (MSF), ethyl acetate (ESF), chloroform (CSF) and petroleum ether (PSF) were prepared from the dried powder of the whole plant by the modified Kupchan method. Total phenolic content and flavonoid content were determined by Folin Ciocalteu method and aluminum chloride colorimetric method, respectively. The antioxidant activity was assessed by the DPPH radical scavenging and total antioxidant capacity assays. The antibacterial activity was determined by the disc diffusion method and cytotoxicity was evaluated by the brine shrimp lethality bioassay. Thrombolytic activity was assayed using streptokinase as standard.ResultsQualitative analysis of phytochemical revealed the presence of phenolics and flavonoids along with other bioactive constituents. Among the extractives, CSF contained the highest content of phenolics (155.46 ± 0.52 mg GAE/g) and flavonoids (345.17 ± 1.12 mg QE/g) and exhibited the most potent antioxidant activity in terms of total antioxidant capacity (179.01 ± 0.89 mg AAE/g) and DPPH scavenging ability (IC50; 15.31 ± 0.32 µg/mL). Similarly, CSF showed the highest cytotoxicity with LC50 values of 13.80 ± 0.23 µg/mL, and thrombolytic activity with 43.94 ± 0.62% clot lysis. The fraction also exhibited broad spectrum antibacterial activity. A significant correlation was observed between the flavonoid content and total antioxidant activity (r2 = 0.894, p < 0.05), while high correlation was seen between phenolic and flavonoid content and DPPH radical scavenging, total antioxidant capacity and cytotoxicity (r2 = 0.612–0.928). Similarly, a positive correlation was found between phenolic and flavonoid content with thrombolytic and antibacterial activities.ConclusionThese results revealed that C. asiatica is a rich source of phenolics and flavonoids and correlated with antioxidant, cytotoxicity, antibacterial and thrombolytic activities. Hence isolation of phenolics and flavonoids from this plant may offer potential candidates which may be effective in the prevention of many chronic diseases.

Antioxidant activity of venison subjected to in vitro cooking and gastrointestinal digestion and isolation of its 2,2-diphenyl-1-picrylhydrazyl radical scavenging peptides.

Venison, a type of game meat, has several health benefits because it contains not only high protein and low fat but also bioactive peptides with several physiological properties, including antioxidative and angiotensin-converting enzyme inhibitory properties. The aim of the present study was to investigate the antioxidant activity of venison treated by in vitro cooking and gastrointestinal digestion. We subjected venison along with pork and beef to in vitro cooking and digestion and assessed their antioxidant activity via 2,2-diphenyl-1-picrylhydrazyl radical scavenging (DPPH-RS) and hydrophilic oxygen radical absorbance capacity (H-ORAC) assays. The peptide contents of all types of cooked and digested meat samples were higher than those of the untreated and cooked samples. The DPPH-RS activities and H-ORAC of digested venison, pork, and beef were increased compared with those of untreated samples. DPPH-RS activity was significantly higher in the digested venison samples than in the digested pork and beef samples. In this study, several fractions of digested venison from the chromatography exhibited DPPH-RS activity. Peptide analysis, using liquid-chromatography with tandem mass spectrometry, unveiled two peptides DIDDLELTLAK and TQTVCNFTDGALVQHQEWDGK with high DPPH-RS activities. Thus, venison is a rich source of antioxidant peptides and potentially demonstrate an antioxidation ability by digestive enzymes in vivo.

Amazonian Fruit Mari-Mari (Cassia leiandra Benth.): Identification of Flavonoids and Antioxidant, Antimicrobial and Antiproliferative Properties

Mari-mari (Cassia leiandra Benth.) is an Amazonian native fruit that is highly appreciated in the northern region of Brazil, but there are few studies regarding its chemical composition and/or biological properties. A phytochemical study was conducted on the extracts of the pulp, peel and seeds; and their antioxidant, cytotoxic and antimicrobial potential were also determined. Methanol and acetone extracts from different fruit parts were subjected to total phenolic, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and FeIII reducing capacity (FRAP) assays. From the peel extracts, the engeletin and astilbin could also be isolated and characterized based on nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry. A quantification using ultra-fast liquid chromatography of acetone dry crude extracts (DCE) of the peel showed that engeletin was the main compound (532.77 mg g-1 DCE). Astilbin content was also determined (131.53 mg g-1 DCE). The antibacterial and antiproliferative activities were evaluated and the methanol extract of the peel showed higher growth inhibition activity against all tested bacteria. Engeletin showed a relevant antimicrobial effect against Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli. Acetone and methanol peel extracts exhibited a relevant inhibitory effect on the proliferation of breast carcinoma cells (MCF-7), with no toxicity to the normal cell line (NIH/3T3).

Effect of choline chloride-based deep eutectic solvents on polyphenols extraction from cocoa (Theobroma cacao L.) bean shells and antioxidant activity of extracts

The effective extraction of natural compounds from cocoa bean shells using deep eutectic solvents could contribute to the sustainable valorization of this waste material. The objective of this study was to: (1) analyze the extraction kinetics of polyphenols released from cocoa (Theobroma cacao L.) bean shells (CBS) by the solid-liquid extraction method using choline chloride-based deep eutectic solvents (ChCl-DES) and their aqueous solutions; (2) investigate the effect of choline chloride-based deep eutectic solvents (ChCl-DES) aqueous solutions on in-vitro antioxidant capacity and the main individual compounds of the extracts. ChCl-DES were prepared with lactic acid, glycerol, and ethylene glycol in a 1:2 ratio. Aqueous solutions (30%, 40%, and 50% water) to obtain solvents with different physicochemical properties were performed. The total phenolic content (TPC) was determined by the Folin-Ciocalteu method. The solution of Fick's law model for plate geometry particles was applied to fit the experimental data and calculate the effective diffusivity coefficient (De). The antioxidant capacity of the extracts was analyzed by a combination of 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH) free radical scavenging capacity and ferric-reducing antioxidant power (FRAP) assays. The main bioactive compounds were quantified by high-performance liquid chromatography. The results showed that the type of hydrogen bond donor influences the total phenolic content, antioxidant activity and the main individual compounds in the extracts. Moreover, the washing/diffusion mechanism adequately depicts the extraction kinetics data for total phenolic content. However, the influence of an additional mechanism that enhanced the extraction capacity of deep eutectic solvents compared with organic solvent was confirmed.