FRAP Values Research Articles

Bioactive characterization of multifloral honeys from Apis cerana cerana, Apis dorsata, and Lepidotrigona flavibasis

Honey is a complex food product, and has been linked to a number of substantial health advantages. The aim of this study was to assess the phenolic compounds, organic acids, microbial community, antioxidant activity, and antimicrobial activity of multifloral honeys produced by Apis cerana cerana, A. dorsata, and Lepidotrigona flavibasis in Hainan province, China. Our results illustrated that chlorogenic acid was the major phenolic component in all honeys. L. flavibasis honey showed the greatest antioxidant activity (DPPH IC50 value, 7.66 mg/mL; FRAP value, 5217.06 µmol TE/kg), as well as the highest levels of proline (548.64 mg/kg), total flavonoid (11.67 mg QE/100 g), total phenolic (132.73 mg GAE/100 g), and Lactobacillus (96.28 %). Besides, all honeys were found to have a broad spectrum of antibacterial activity. Overall, our data imply that Hainan honeys, particularly stingless bee honeys, have been beneficial components of human diets.

Spectroscopic and tensiometric considerations on anionic surfactants (SDS) and ascorbic acid/ascorbates interactions

The cosmetics and personal care products market is developing dynamically and the formulations of products are subject to numerous modifications due to consumer expectations and market trends. An increase in demand for products containing ascorbic acid or its more stable forms has been observed for several years. In this study, the correlation between SDS and ascorbic acid or its derivatives in aqueous solutions was assessed using spectroscopic and tensiometric methods. The influence of SDS interactions on the total antioxidant capacity of ascorbic acid/ascorbic acid derivatives was analyzed. The highest FRAP values of SDS-AA2G and SDS-EAC systems (0.17 and 2.71 mmol Fe2+/g, respectively) were at SDS concentration of 0.40 mM and were much higher than the ones of pure ascorbic acid derivatives. Based on the surface tension isotherms and Szyszkowski's equation, it was found that for the tested SDS/ascorbic acid, ascorbyl glucoside and 3-O-ethyl ascorbic acid systems, the CMC values were: 3.85, 2.54 and 3.31 mmol/dm3. There was also an influence on the values of the adsorption parameters, i.e. the surface excess at the saturated interface, the minimum molecular area in the adsorption layer at the saturated interface and the Gibbs free energy of adsorption. Moreover, in most of the analyzed cases, the tested systems had better wetting properties, which resulted in lower values of the contact angle than in the case of pure SDS solution.

In vitro Antioxidant and Antimicrobial Studies of Ethanolic Plant Extracts of P. granatum, O. stamineus, A. bilimbi, M. nigra, and E. longifolia.

Acne is a serious skin problem that affects mostly adolescents. The topical and systematic therapies are effective but could lead to several side effects and the emergence of antibacterial resistance of the acne-causing bacteria. Plant resources have been used as traditional medicine for centuries and can be the alternative therapies for acne treatment. Antioxidants are compounds that can prevent or delay the oxidation of substrates when present in low concentrations. Antioxidants are usually involved in several mechanisms of action, including the inhibition of free radical generation, enhancement of the scavenging capacity against free radicals, and reducing power. In this study, three antioxidant assays, DPPH, ABTS, and FRAP were used to evaluate the antioxidant properties of the ethanolic extracts of five plant extracts (A. bilimbi, M. nigra, O. stamineus, P. granatum, and E. longifolia). Furthermore, the study aimed to identify the most potent plant extracts and their combination which could provide better antibacterial activities against acnecausing bacteria. Ethanolic extracts of A. bilimbi, O. stamineus, M. nigra, P. granatum, and E. longifolia were prepared by the Ultrasound-Assisted Extraction (UAE) technique. Their phytochemical contents were screened using several biochemical tests and GC-MS analysis. The study found that only the extracts of P. granatum and O. stamineus exhibited good antioxidant activity using DPPH assay (82.37% and 81.72% μg/mL respectively) and in ABTS assay (87.25% and 88.85% μg/mL respectively); their observed FRAP values were 115.1667 ± 5.6182 and 41.3860 ± 2.4583 μg/mL, respectively. The preliminary antibacterial screening using the disc diffusion method showed that P. granatum and O. stamineus were the most potent extracts; hence, both extracts were combined at the ratios of 1:1, 1:2, and 2:1 to a total concentration of 400 mg/mL. The antibacterial efficacy of the mixture was studied using the disc diffusion method and the MIC value was determined. Both S. aureus and S. epidermidis were sensitive to all the individual and combined extracts but C. acnes was resistant to all of them. The antibacterial activity of the combined extracts against S. aureus showed a synergistic effect at the ratio of 2:1 with the inhibitory zone diameter of 18.00 ± 1.00 mm and MIC value of 12.5 mg/mL; however, antagonistic effects were observed against S. epidermidis while no effect was noted against C. acnes. Therefore, all the selected plant extracts exhibited antibacterial activities against certain bacteria and their effects may be enhanced by combining the plant extracts.

Formulation and Evaluation of Body Lotion Containing Aegle Marmelos Leaf Extract

Skin is the maximally exposed part of the body, that is susceptible to UV radiation, pollution, etc. A body lotion can aid in protection of skin from these detriments with no side effects. Also, there is a growing arena towards natural and herbal cosmetic products for skincare. Keeping all these in mind, this herbal body lotion was prepared from the extract of Aegle marmelos leaves along with other ingredients to form various formulations. Various studies demonstrated medicinal and immunomodulator activities of Aegle marmelos leading to treatment and preventive strategies incombating vivid conditions. Several antioxidant components such as β-carotene, glutathione, α-tocopherol, ascorbic acid, and total polyphenols and flavonoids are rich in Aegle leaves. The objective of our study was to find out the antioxidant potential of Aegle marmelos and thereby using the extract for formulating body lotion for skincare. These formulations were further evaluated for various parameters such as antioxidant assays (DPPH, FRAP, TPC), pH, lotion type, emulsion type, stability, microbial growth, organoleptic properties, spread ability, etc. Body lotion containing methanolic extract of Aegle marmelos showed 50% radical scavenging activity at 172.51 ± 5.60 mg/mL, TPC value of 28.06 ± 0.40 mg/g and FRAP value of 4.08 mM/g. According to the feedback obtained from the volunteers, the colour of lotion was found to be very good, odour and homogeneity of the body lotion was found to be excellent. The spreadability and emolliency was also found to be excellent. The lotion was found to be non-greasy and maximum volunteers did not experience any sort of irritancy. Further studies are needed to test the efficacy of this lotion in various forms like nanoparticles, etc.

Comparative Insights into the Antimicrobial, Antioxidant, and Nutritional Potential of the Solanum nigrum Complex

Solanum nigrum is a traditional medicinal plant renowned as a cure for many diseases due to the presence of bioactive compounds. The Solanum nigrum complex refers to a group of more than 30 closely related but morphologically distinct taxa. Five indigenous taxa of this complex were investigated for their medicinal potential by using methanolic extracts. The efficacy of each plant was different for each of the seven bacteria studied. On comparing the MIC values, S. americanum was found to be most potent against Bacillus licheniformis (34 µg/mL), S. chenopodioides against Escherichia coli (78 µg/mL), S. nigrum against Bacillus licheniformis (49 µg/mL) and Escherichia coli (49 µg/mL), S. retroflexum against Escherichia coli (30 µg/mL), and S. villosum against Proteus mirabilis (45 µg/mL). The extracts were also subjected to six antioxidant assays. Moderate scavenging activity was observed by all plants in the DPPH free radical assay, but S. chenopodioides was the most effective. The total phenolic contents of the five plants were comparable, but the gallic acid equivalents of S. americanum and S. nigrum were the highest (26.58 mg/100 g GAE). The highest Trolox equivalent antioxidant capacity was observed for S. retroflexum, with the ABTS assay giving a TEAC value of 33.88 mM/100 g of dry weight. Metal-chelating activity against Fe2+ was observed to be highest for S. chenopodioides (70.37%). The FRAP value of S. nigrum was the highest (8.5 mM FeSO4·7H2O) among all taxa. The lipid peroxidation trend was very similar for all five samples. The results suggest the specified medicinal use of different members of the Solanum nigrum complex, which will also have significant nutritional value.

Valorisation of Roman chamomile (Chamaemelum nobile L.) herb by comprehensive evaluation of hydrodistilled aroma and residual non-volatile fractions

Valorization of botanicals for the development of natural food-grade ingredients is an important task in terms of sustainability and processing waste reduction. In this study, Roman chamomile (Chamaemelum nobile L.) herb was collected at six different vegetation phases in the period 26 May – 23 August 2019 and subjected to biorefining into the several valuable fractions. The yield of hydro-distilled essential oil (EO) was in the range of 0.22% (intensive vegetative growth) to 0.80% (full flowering). Angelic, isobutyric, butyric and methacrylic acid esters and some monoterpene and sesquiterpene derivatives were the major EO constituents: 3-methylpentyl angelate (20.11–27.56%), methallyl angelate (7.28–10.33%), isoamyl angelate (5.57–9.02%), isobutyl angelate (4.84–6.79%), 2-methylbutyl angelate (3.11–6.32%), 3-methylamyl methacrylate (5.04–6.17%), 3-methylpentyl isobutyrate (4.29–6.64%), 3-methylamyl isobutyrate (4.29–6.64%), α-pinene (1.61–6.37%) and pinocarvone (1.46–4.67%). In order to valorize water soluble and solid EO distillation residues their antioxidant potential was evaluated by several in vitro assays: water extracts were considerably stronger antioxidants than acetone extracts isolated from the solid residues. Water extracts of the plants collected at flowering phases were the strongest antioxidants; their TPC, FRAP and ORAC values were up to 143.2 mg gallic acid equivalents/g, 650, and 5601 μmol TE/g dry extract, respectively, while effective concentrations (EC50) of DPPH• and ABTS•+ scavenging, were down to 0.59 and 0.49 mg/mL, respectively. Among 7 tentatively identified by UPLC/Q-TOF/MS phenolic constituents the intensity of molecular ion of 3,5-dicaffeoyl quinic acid was the largest. The results obtained may assist for developing flavorings, antioxidants and health beneficial preparations from C. nobile extracts.

Effects of Different Edible Coatings on the Shelf Life of Fresh Black Mulberry Fruits (Morus nigra L.)

The aim of this study was to evaluate the effects of edible coatings based on gelatine, oils (sunflower and coconut) and beeswax on the physicochemical properties, bioactive compounds (total phenols and monomeric anthocyanin content), antioxidant capacity (DPPH and FRAP assays were used) and sensorial attributes of mulberry fruits during a period of storage (0, 2, 5 and 8 days) at 4 °C. The results showed that, in all samples treated with edible films, the degree of firmness was higher and the deterioration weaker compared to the control at day 8 of storage. Edible coatings significantly reduced the rate of deterioration, in terms of total phenolics and anthocyanins, in mulberry fruits over time, and the gelatine-coated mulberry samples (G_Mn) exhibited the best results. In terms of the antioxidant capacity of the coated mulberry, after 5 and 8 days of storage, only the G_Mn samples maintained significantly high DPPH radical scavenging and FRAP values compared to control. Coating improved the sensorial attributes of the mulberry during storage, and gelatine-coated fruits recorded the highest score, followed by layer-by-layer samples (O+W_G_Mn). All edible coatings used to cover black mulberry in this study extended the shelf life of the fruits, while maintaining high levels of bioactive compounds and, consequently, high antioxidant capacity, along with improved sensory qualities, during cold storage.

Techno-functional properties of protein from protease-treated brewers’ spent grain (BSG) and investigation of antioxidant activity of extracted proteins and BSG residues

The study aimed to investigate the biological properties of the protein fraction of brewers’ spent grain (BSG) and its sediments as well as the techno-functional properties of BSG protein (BSGP). BSG was incubated with 0.5% protamex and a combination of protamex and flavourzyme, in addition to the control (incubation without protease). The results showed that enzymatic treatment enhanced the antioxidant activity of BSGP. Compared to the sediment fraction, BSGPs had higher antioxidant capacities than those in sediments. The current study demonstrated that the FRAP value is aligned with the amount of the polyphenolic compounds, while BSGP is responsible for ORAC and ABTS capabilities. Enzyme treatment on BSG enhanced the antioxidant properties of BSGPs and the amount of the phenolic compounds of the sediments. BSGPs treated with proteases possessed higher oil-holding capacity, foaming properties and lower emulsion capability. In conclusion, enzymatic treatment of BSG enhanced the protein functionality and bioactivity as well as intensified the antioxidant activity of its sediments allowing further valorization.

Comparative Study of Chemical Characteristic Analysis of Different Solvent-Extracted Solanum lycopersicum (Tomato Seed) Oil.

Tomato seeds are large waste byproducts from the processing of tomato into various food products like juice, sauce, and puree. One of the most potential uses of these tomato seeds is as a source of edible vegetable oil. The present study investigated the chemical characteristics including antioxidant activity, oxidative stability, and fatty acid composition of tomato seed extracted oil by aqueous and nonpolar (hexane) solvent. Fatty acid composition of tomato seed oils was determined by gas chromatography. Tomato seed oils were found to contain huge amount of linoleic acid, followed by oleic acid, palmitic acid, stearic acid, and linolenic acid. Polyunsaturated fatty acid and monounsaturated fatty acid content of the oil is near about 58% and 24%, respectively. Oxidative stability test of oil samples were evaluated by acid value, peroxide value, anisidine test, and TBA value. Antioxidant activity based on DPPH, FRAP, and ABTS assay of tomato seed oils was analyzed. The oil showed higher antioxidant activity-DPPH value (72-75%), FRAP value (9-11 µ mol/ml), and ABTS (37-39%). The results indicate hardly any difference in the fatty acid composition and antioxidant activity between aqueous and extracted and solvent-extracted tomato seed oil.

Ranunculus gracilis Clarke Rizomunun In Vitro Biyolojik Aktiviteleri

R. gracilis rhizomes were picked from Yenice Forests Karabük province in Turkey. Ethanol was chosen for extraction solvent. Disc diffusion method including filamentous and non-filamentous Gram-positive bacteria, Gram-negative bacteria, and yeast strains was used to evaluate the antimicrobial activity of the extract. DPPH free radical scavenging activity and ferric reducing antioxidant power analysis were performed to determine antioxidant activity. The Folin-Ciocalteu method for determining the total phenolic amount and the AlCl3 method for the total flavonoid content of the extract was chosen. Mean diameters of inhibition zones (IZD) of the bacteria were found in the range of 8.2 mm to 24.45 mm. This value was measured as 17.82 mm and 18.69 mm for yeasts. The total antioxidant activity value of the extract was calculated as 7.08 mg AAE/g extract. The IC50 value was found as 9.097 mg/mL for DPPH free radical scavenging activity. The FRAP value indicated that the reducing power of 1 gram of sample was equivalent to 4.66 μmol of Trolox. The total phenolic content of ethanol extract of R. gracilis rhizomes was determined as 0.414 mg GAE/g, while the flavonoid content was calculated as 0.68 mgQE/g. The analyzed ethanolic extract of R. gracilis rhizomes demonstrated that the biological activity level could be considered significant according to the obtained results.

The effect of electron beam irradiation on the microbial stability and quality characteristics of vacuum‐packaged ready‐to‐eat potato

We studied the microbial stability and quality of vacuum-packaged ready-to-eat (RTE) potatoes irradiated by different doses of electron beam during storage. Results showed that irradiation effectively reduced the total bacterial count of samples, with a maximum reduction of 7.08 log units by irradiation at 5 kGy. Irradiation at dose ≥7 kGy completely inactivated the microorganisms. Potato color and texture were affected when the irradiation dose was ≥3 and ≥5 kGy, respectively, which may be due to the reduction of a* value and chewiness of samples. An electronic nose could effectively distinguish the odor of the irradiated samples from the non-irradiated ones. Irradiation significantly reduced potato Vc content but it had no effect on the moisture and total protein content. Potato DPPH activities were increased by irradiation at dose ≤5 kGy but decreased when the dose was ≥7 kGy. The FRAP values were reduced in all irradiated samples. Novelty impact statement This work investigated the effect of electron beam irradiation on microbial stability and quality characteristics, including sensory quality, texture, odor, nutritional properties, and antioxidant capacity of vacuum-packaged RTE potatoes. Based on the results, an optimum dose for RTE potatoes decontamination was also suggested. Results would provide the basic data for the wider application of electron beams in RTE vegetable preservation.

Phytochemical constituent and oxidative potencies of acetone, methanol and aqueous leaf extracts of Acalypha Wilkesiana grown at the Kaura Namoda plant nursery

As a result of increased interest in the production of plant-based drugs for the treatment of many diseases has become a significant reason why people have become more coversant in the use of traditional medicine for the treatment of mild and serious illness. Due to increase in the thrust for the production of plant-based drugs, this present study was carried out to compare the phytochemical constituents and antioxidant potencies of acetone, methanol and aqueous leaf extracts of Acalypha wilkesiana collected from Kaura Namoda Botanical Garden in Zamfara State-Nigeria. The antioxidant activities was evaluated using various assays; The total phenolic content of aqueous, methanol and acetone leaf extract were 15.58 0.66 mg GAE/g, 14.10 2.17 mg GAE/g and 8.70 0.01 mg GAE/g respectively. Total flavonol contents; 207.10 11.53 mg QE/g, 196.08 5.53 mg QE/g and 112.04 8.27 mg QE/g respectively. Total flavonoid contents; 240.99 9.50 mg QE/g, 252.52 3.73 mg QE/g and 123.88 5.58 mg QE/g respectively. FRAP values were 679.14 0.45 mmol/g, 611.90 7.09 mmol/g and 292.07 11.38mmol/g respectively. ABTS activity of aqueous, methanol and acetone leaf extract were 24.30 5.86 mg AAE/g, 14.49 1.02 mg AAE/g and 7.00 0.57 mg AAE/g respectively, methanol leaf extract had the highest percentage DPPH Inhibition value of 42.64 5.13, followed by aqueous (31.77 4.08) at 0.25mg/ml while aqueous had the highest (52.63 0.67), followed by methanol extract (44.80 2.80) at 0.50mg/ml. Aqueous extract had the highest percentage inhibition of Nitric Oxide with a value of 59.74 1.30, followed by methanol extract (46.11 2.54) at 0.25mg/ml. inhibition for aqueous was also highest at 0.5 mg/ml. Aqueous extract had the highest percentage lipid peroxidation inhibition value of 22.66 2.93, followed by methanol leaf extract with the value of 18.89 0.80 while at 0.50mg/ml methanol leaf extract had the highest percentage inhibition of lipid peroxidation (39.42 3.10), followed by aqueous leaf extract with the value of 31.48 1.61. The results showed that aqueous and methanol leaf extract of Acalypha wilkesiana displayed potent antioxidant effects with the aqueous having an edge. This present study therefore supports the view that Acalypha wilkesiana can be used in the management of oxidative stress and other related diseases.

Metabolomics-Based Profiling, Antioxidant Power, and Uropathogenic Bacterial Anti-Adhesion Activity of SP4TM, a Formulation with a High Content of Type-A Proanthocyanidins.

Flavonoids and proanthocyanidins (PACs) have been the subject of intense scientific investigations, both for their antioxidant properties and anti-adhesion activity against uropathogenic bacteria. We investigated the metabolomics and antioxidant capacity of SP4TM, a patent-pending formulation based on a mixture of plant extracts with a high content of bioactive PACs and other polyphenols. The total content of polyphenols (885.51 ± 14.19 mg/g), flavonoids (135.52 ± 8.98 mg/g), anthocyanins (54.84 ± 2.97 mg/g), and PACs (379.43 ± 12.44 mg/g) was quantified using UV-Vis assays. Use of HPLC-ESI-MS/MS revealed the presence of 5 flavanols (100.77 ± 3.90 mg g−1 d.wt), 11 flavonols (59.96 ± 1.83 mg g−1 d.wt), and 8 anthocyanins (46.96 ± 1.59 mg g−1 d.wt), whereas MALDI-TOF MS showed that SP4TM contains PACs with one or more type-A interflavan bonds at each degree of polymerization. Regarding antioxidant properties, LUCS technology on HepG2 cells evidenced the ability of SP4TM to neutralize intracellular free radicals, inhibit membrane lipid peroxidation, quench H2O2, and reduce free radicals mainly through chelating mechanism, as demonstrated by a higher FRAP value (2643.28 ± 39.86 mmol/g) compared with ABTS (139.92 ± 6.16 mmol/g) and DPPH (89.51 ± 3.91 mmol/g). Finally, the SP4TM type-A PAC content strongly prevented bacterial adhesion of P-fimbriated uropathogenic Escherichia coli (0.23 mg/mL). In conclusion, SP4TM has a strong antioxidant capacity involving multitarget mechanisms and is a potential supplement to fight urinary tract infections due to its ability to inhibit uropathogenic E. coli adhesion.

Response surface methodology applied to subcritical solvent extraction of brazilin compound from Caesalpinia sappan L. heartwood

Subcritical solvent extraction technique could be used to extract brazilin from Caesalpinia sappan L. heartwood (CSH). The optimal experimental condition for the subcritical solvent extraction, simultaneously giving the highest percentage yield of dried crude extract sample (9.95%), maximal brazilin content (84.65 mg/g dry heartwood), the lowest IC50 values of DPPH and ABTS scavenging activities (11.42 and 8.62 μg/mL extract, respectively) and the highest FRAP value (12.11 μM FeSO4 equivalents/100 μL extract) of the CSH extract were obtained using ethanol: water (3:1 w/w) as the solvent and a solvent: CSH ratio of 9:1 (w/w) at 100 °C for 50 min. Under this optimal extraction condition, the heartwood extract exhibited antibacterial activity against bacteria which had the minimal inhibitory concentration and minimum bactericidal concentration values of 0.98 and 1.45, 1.96 and 2.94, 3.91 and 3.91, and 3.91 and 3.91 mg/mL to inhibit and kill Staphylococcus aureus, Bacillus subtilis, Bacillus cereus and Escherichia coli, respectively. The obtained data might substantiate the potential health benefits of the crude extract and brazilin compound of Caesalpinia sappan L. heartwood, as potential natural antioxidant and antimicrobial ingredients in food, food supplements, cosmetic and pharmaceutical production, and, also, as food preservatives or coloring agents in the food processing industries.

Effects of extraction methods on antioxidants and methoxyflavones of Kaempferia parviflora

This research was aimed to determine the effects of extraction methods on antioxidant properties and methoxyflavone contents of Kaempferia parviflora (KP) rhizome extracts. The KP rhizomes were extracted by maceration using ethanol at the concentrations of 25, 50, 75 and 95% V/V for 7 days and 95% V/V ethanolic extraction with sonication-assisted extraction (SAE) for 15-45 mins. Antioxidant components (phenolics, flavonoids and anthocyanins) and antioxidant activities (DPPH and FRAP) were examined. Methoxyflavones of the KP extracts were identified by a GC-MS technique. It was found that extraction methods affected the antioxidant properties of the extracts. Increasing ethanol concentrations enhanced anthocyanins but not phenolics and flavonoids. Ethanol concentration at 75% V/V exhibited the greatest DPPH while 25% V/V ethanol showed the greatest FRAP values. In this study, 10 methoxyflavones from KP extracts were separated and identified by GC chromatograms. The content of 5,7-dimethoxyflavone increased from 1.1 g/100 mL extract to 48.10 g/100 mL extract as the ethanol concentrations increased from 25% to 95% V/V. SAE for 15-45 mins had little impact on antioxidant properties as well as methoxyflavone contents. In general, SAE enhanced the extraction of KP rhizomes by increasing 5,7-dimethoxyflavone contents.

Comparative Examination of Phytonutrients and Antioxidant Activity of Commonly Consumed Nuts and Seeds Grown in Vietnam

The aim of the present study was to determine the phenolics, carotenoids, B-vitamins, and antioxidant activity of nuts and seeds grown in Vietnam. The concentrations of carotenoids and B-vitamins may vary among the nuts and seeds. Watermelon seed contained the highest level of lutein while pumpkin seed was the β-carotene richest sample. Sachi inchi and sunflower seed comprised considerable levels of vitamin B1, B6, and B9. The phenolic analysis revealed that cashew contained the highest total amount of flavonoids (466.04 μg/g), with catechin, epicatechin, and procyanidin B2 predominating over the other flavonoids. Likewise, chlorogenic and neochlorogenic acids made up the highest total amount of phenolic acids in sunflower seed (1870.41 μg/g). Walnut appeared to possess the highest antioxidant activity evaluated by DPPH, ABTS, FRAP, and reducing power assays. The correlation analysis indicated strong positive correlations between total phenolic content with DPPH and FRAP values. Principal component analysis graphically showed the distant positioning of cashew and sunflower seed, highlighting their significantly higher levels of phenolics. The findings of the study would be useful to improve nutrient database contents for flavonoids and phenolic acids as well as to promote the consumption of nut and seed products in Vietnam.

Polyphenols and Flavonoids Composition, Anti-Inflammatory and Antioxidant Properties of Andean Baccharis macrantha Extracts.

This study examined the leaves of Baccharis macrantha to obtain extracts of Baccharis macrantha (EBM) and to determine the total flavonoid content (TFC) and the total polyphenol content (TPC). The main objective of this work was to quantify TPC and TFC of extracts of B. macrantha from Ecuador and evaluate its antioxidant and anti-inflammatory activities and inhibition of lipid peroxidation. The extraction method was optimized with solvents, ethanol, and methanol, at temperatures of 30–60 °C and extraction times of 5–20 min. The optimal TFC extraction conditions were at EtOH25% at 50 °C for 10 min. The optimal TPC extraction conditions were at EtOH50% at 50 °C for 10 min. EBM was characterized by TLC and HPLC with three standards: gallic acid, catechin, and quercetin. EBM-EtOH25% and EBM-EtOH50% obtained at 50 °C for 10 min were used to identify quercetin and evaluate biologicals activities. Quercetin was detected in EBM (EtOH25% and EtOH50%). EBM anti-inflammatory activity was evaluated with the red blood cell stabilization (RBC) method. The RBC model showed values of 49.72% of protection lysis RBC to EBM-EtOH25% and 50.71% of protection lysis RBC to EBM-EtOH50%. The EBM in vitro inhibition of lipid peroxidation showed a protection of 77.00% (EtOH25%) and 73.11% (EtOH50%) when the TBARs method was used. EBM-EtOH25% and EtOH50% showed high antioxidant activity. EBM-EtOH25% presented values of ABTS (1172 µmol TE/g EBM), DPPH (836 µmol TE/g, EBM), and FRAP (85.70 µmol TE/g, EBM).

From agricultural waste to antioxidant-rich extracts: Green techniques in extraction of polyphenols from sugar beet leaves

Different conventional and “green” extraction techniques (solid/liquid extraction, microwave and ultrasound assisted extraction, pressurized liquid extraction and subcritical water extraction) were tested using different operating conditions in the recovery of valuable polyphenol compounds from sugar beet leaves. All tested extraction techniques provided considerable extraction yield in the range from 18.21% to 37.04%. Total phenolic content ranged from 0.4504 up to 1.7171 (g GAE/100 g DW) with the highest values obtained by using microwave and ultrasound assisted extraction. Extraction parameters had highly significant effect on the concentration of bioactive compounds recovered by pressurized liquid extraction and subcritical water extraction. Individual phenolic profile of sugar beet leaves extracts largely depended on the applied extraction technique, however, vitexin was the most abundant phenolic compound present in all extracts regardless of the extraction technique. Investigation of extracts antioxidant activity through DPPH, FRAP and ABTS values indicated the lowest antioxidant activity of extracts obtained by solid/liquid extraction compared to other extraction techniques.

The pharmaceutical applications of total flavonoids extract from Isatis tinctoria L. leaves

Isatis tinctoria L. leaves (Folium isatidis), as dried leave of the isatis indigotica in the cruciferous family, has a variety of pharmacological effects, including regulation of immune function, anti-inflammatory, bacteriostasis, antipyretic effect. In this study, total flavonoids extract from Folium isatidis was systematically studied about extractive process, main components, antibacterial, antioxidant and anti-inflammatory activities. The total flavonoids extract yield was (7.65±0.07)% under the optimal extraction parameters of ethanol concentration 54.37%, ratio of solvent volume to material weight 40:1 ml/g, and ultrasonic extraction time 20 min. Nineteen chemical components were inferred and identified by UPLC-QTOF-MS method. Although the extract showed mild antibacterial and antioxidant effects with MIC values 31.25, 62.5, 125 and 125 mg/ml against Streptococcus, Salmonella, Staphylococcus aureus and Escherichia coli, and IC50 DPPH 12.64 µg/ml, IC50 ABTS 16.72 µg/ml and FRAP value at 0.11 mmol Fe2+/100 µg/ml compared with the positive control butylated hydroxytoluene with IC50 DPPH 8.13 µg/ml, IC50 ABTS 2.22 µg/ml and FRAP value at 0.16 mmol Fe2+/100 µg/ml. It exhibited better anti-inflammatory effects in LPS induced RAW 264.7 cell (50, 100 and 200 µg/ml of TFE) and ALI mice (100, 250, or 500 mg/kg•b•w of TFE), which was demonstrated by reducing cell phagocytic activity, decreasing the content of pro-inflammatory cytokine and inflammatory mediator, and improving lung tissue injury. Furthermore, the mechanism of anti-inflammatory action was further revealed to be related to the regulation of TLR4-TRIF-NF-κB signaling pathway. These studies revealed that total flavonoids extract could be used as a natural and green candidate for anti-inflammatory drugs and enrich the variety of clinical anti-inflammatory drugs.

Serum levels of vitamin A, selenium, and better dietary total antioxidant capacity are related to lower oxidative DNA damage: A cross-sectional study of individuals at cardiovascular risk

The risk for cardiovascular diseases (CVR) has been associated with oxidative DNA damage, but the genetic and environmental factors involved in the antioxidant and DNA repair system contributing to this damage are unknown. The aim was to evaluate the levels of oxidative DNA damage in CVR subjects and how it is related with some genetic and nutritional factors. The cross-sectional study evaluated 136 individuals of both sexes, aged 20–59 years, with at least one cardiovascular risk factor. The global risk score was used to classify individuals at low, intermediate, and high cardiovascular risk. The dietary total antioxidant capacity (DTAC) was calculated using table with FRAP values. The oxidative DNA damage was verified by the comet assay. The variants null of Glutathione-S-transferases Mu1 and Theta 1(GSTM1 and GSTT1) and rs25487 of X-Ray Repair Cross Complementing Protein 1 (XRCC1) were analyzed by real-time PCR and PCR-RFLP, respectively. The oxidative DNA damage was higher in patients with intermediate/high CVR than in patients with low CVR (P=.01). Individuals with GSTT1/GSTM1 null genotypes or arg/gln+gln/gln genotypes of the XRCC1 (rs25487) gene showed similar levels of oxidative DNA damage compared wild genotype. Multivariate regression analysis demonstrated that oxidative DNA damage in individuals with CVR depends on serum levels of vitamin A, selenium, and DTAC independently of the other factors [F(6.110)=8.213; P<.001; R2=0.330]. These findings suggest that nutritional factors such as DTAC, vitamin A and selenium may have a protective effect against oxidative DNA damage in these individuals.