Antioxidant Properties Of Methanolic Extracts Research Articles

The Antibacterial and Antioxidant properties of Methanolic extracts of Selected Medicinal Plants in Jordanian Folk Medicine in Relation to their Phenolic content

The Antibacterial and Antioxidant properties of Methanolic extracts of Selected Medicinal Plants in Jordanian Folk Medicine in Relation to their Phenolic content

Investigation of Antimicrobial and Antioxidant Activities of some Lichens

This study investigated the antimicrobial and antioxidant properties of methanol extracts from five lichen species: Polycauliona candelaria (Syn. Xanthoria candelaria), Nephromopsis chlorophylla (Syn. Cetraria chlorophylla), Circinaria calcarea (Syn. Aspicilia calcarea), Bryoria capillaris (Syn. Alectoria cana), and Peltigera canina (Syn. Dermatodea canina). Antimicrobial activities were determined using the agar disc diffusion method, while minimal inhibitory concentration (MIC) values were determined using the micro-well dilution method. Among the lichen species, methanol extract of Circinaria calcarea exhibited the highest antimicrobial activity, with a 15 mm zone of inhibition against Escherichia coli and Bacillus cereus. It also demonstrated the lowest MIC value (31.25 μg/mL) against Bacillus cereus, Bacillus subtilis, Clostridium perfringens and Escherichia coli were the most sensitive microorganisms to lichens. Various antioxidant determination methods were employed to assess the antioxidant activities of the lichens, including ferric ion (Fe+3) reduction capacity, cupric ion (Cu+2) reduction capacity, ferric ion reducing antioxidant power (FRAP), DPPH radical scavenging activity, DMPD radical scavenging activity and metal chelating activity using the bipyridyl reagent. All lichens exhibited excellent antioxidant activity, particularly in metal chelating activity using the bipyridyl reagent. Peltigera canina demonstrated the highest antioxidant activity among the studied lichen species across most of the applied method.

Effect of Oil Pollution on the Antioxidant Activity of the Methanolic Extracts of Polluted and Unpolluted Leaves of Hyptis suaveolens (L)

Hyptis suaveolens (L.) Poit, an aromatic weed known as pignut or daddoya-ta-daji in the Hausa language, has a longstanding history of usage as food and medicine in Kaduna state. This plant is interestingly found thriving in environments with or without oil pollution. In our modern industrial society, it's practically inevitable that these medicinal plants come in contact with oil contamination. This is largely because oil pipelines, often aged and susceptible to corrosion or illicit activities leading to leakages, are scattered across urban and rural settlements, influencing the plants' phytochemical composition. This study is focused on examining if oil pollution alters the antioxidant activity of this plant. An evaluation of the antioxidant properties of methanol extracts from Hyptis suaveolens (L.) leaves, both from polluted and unpolluted areas, was carried out using the 2,2-Diphenyl-1-Picrylhydrazyl-hydrate (DPPH) free radical scavenging assay. The outcomes showed that the extracts have significant (p < 0.05) concentration-dependent antioxidant activity. Yet, the unpolluted H. suaveolens leaves' methanol extract exhibited superior DPPH radical scavenging action compared to the extract from the polluted leaves. The median inhibitory concentrations (IC50) for the polluted and unpolluted leaves' methanol extracts were 35 µg/ml and 20 µg/ml respectively. Therefore, the contamination had a detrimental impact on the plant extract's antioxidant capacity.

Antioxidant and antimicrobial activities and GC/MS-based phytochemical analysis of two traditional Lichen species Trypethellium virens and Phaeographis dendritica

BackgroundLichens are complex plants living in symbiotic relationship between fungi and algae. They are used for human and animal nutrition and are used in folk medicine in many countries over a considerable period of time. In the present study, various solvent extracts of Trypethelslium virens and Phaeographis dendritica were tested for their antioxidant and antimicrobial activity. ResultsThe phytochemical analysis by GC/MS revealed phenolics (1.273%), terpene (0.963%), hydrocarbons (2.081%), benzofurans (2.081%), quinone (1.273%), alkanes (0.963%), and aliphatic aldehydes (0.963%) as the predominant compounds in Trypethellium virens SPTV02, whereas secondary alcohol (1.184%), alkaloids (1.184%), and fatty acids (4.466) were the major constituents in Phaeographis dendritica. The antioxidant property of methanolic extract of T. virens and P. dendritica revealed the presence of total phenolic and terpenoids. The methanolic extracts of both the lichens exhibited encouraging DPPH antiradical activity, with the IC50 of 62.4 ± 0.76 µg/ml for T. virens and 68.48 ± 0.45 µg/ml for P. dendritica. Similarly, ferric reducing power assay result exhibited higher reducing activity. Further, the lichen extracts (methanolic) indicated promising antimicrobial activities against pathogens showing MIC from 62.5 to 500 µg/ml. ConclusionThe study results concludes that both the lichens could be used as new natural source of antioxidants and antimicrobial agents which can be exploited for pharmaceutical applications.

The influence of fermentation using marine yeast Hortaea werneckii SUCCY001 on antibacterial and antioxidant activity of Gracilaria verrucosa

Abstract. Fatmawati F, Sibero T, Trianto A, Wiyanti DP, Sabdono A, Pronggenies D, Radjasa OK. 2022. The influence of fermentation using marine yeast Hortaea werneckii SUCCY001 on antibacterial and antioxidant activity of Gracilaria verrucosa. Biodiversitas 23: 5258-5266. Gracilaria verrrucosa is producer of agar, a polysaccharide, that widely used in pharmaceutical and food industries. However, several studies have shown that the secondary metabolite of this seaweed is not potential as an antimicrobial and antioxidant agents. This study aimed to determine the antibacterial and antioxidant properties of methanolic extract of G. verrucosa after fermentation using marine yeast Hortaea werneckii SUCCY001. The samples were fermented based on different optimization times, specially in three, six and nine days. Samples were extracted using methanol by maceration method. Then the extracts were tested for antimicrobial potential against the several human clinical pathogens namely Bacillus cereus, Bacillus subtilis, Escherichia coli, Micrococcus luteus and Pseudomonas aeruginosa. The antioxidant potential was analyzed using the 1,1-diphenyl-2-picrylhydracyl (DPPH) and 2,2-Azinobis 3-ethyl benzothiazoline 6- sulfonic acid (ABTS) method while total phenolic content (TPC) was measured using Folin-Ciocalteu. Secondary metabolites were characterized using thin layer chromatography (TLC) and GC-MS. TLC plate visualization using UV light, DPPH, FeCl3 and vanillin-sulfuric acid reagents. The results showed that the extract fermented for nine days was able to inhibit the growth of P. aeruginosa and M. luteus at a concentration of 2 mg/mL. The highest antioxidant activity was found in the nine days fermented extract with an RSA value of 21.9% ± 0,0001 for DPPH and 12.53 % ± 0.002 for ABTS. Furthermore, the highest total phenolic content was found in the nine days fermented extract of 7.57 GAE/mg. The results of characterization using TLC showed the presence of phenolic compounds, terpenoids and antioxidants in fresh seaweed extracts, autoclaved fresh seaweed, three days of fermentation, six days and nine days. Based on this research, it can be seen that the addition of marine yeast starter H. werneckii SUCCY001 was able to increase the antibacterial and antioxidant activity of G. verrucosa.

The influence of fermentation using marine yeast Hortaea werneckii SUCCY001 on antibacterial and antioxidant activity of Gracilaria verrucosa

Abstract. Fatmawati F, Sibero T, Trianto A, Wiyanti DP, Sabdono A, Pronggenies D, Radjasa OK. 2022. The influence of fermentation using marine yeast Hortaea werneckii SUCCY001 on antibacterial and antioxidant activity of Gracilaria verrucosa. Biodiversitas 23: 5258-5266. Gracilaria verrrucosa is producer of agar, a polysaccharide, that widely used in pharmaceutical and food industries. However, several studies have shown that the secondary metabolite of this seaweed is not potential as an antimicrobial and antioxidant agents. This study aimed to determine the antibacterial and antioxidant properties of methanolic extract of G. verrucosa after fermentation using marine yeast Hortaea werneckii SUCCY001. The samples were fermented based on different optimization times, specially in three, six and nine days. Samples were extracted using methanol by maceration method. Then the extracts were tested for antimicrobial potential against the several human clinical pathogens namely Bacillus cereus, Bacillus subtilis, Escherichia coli, Micrococcus luteus and Pseudomonas aeruginosa. The antioxidant potential was analyzed using the 1,1-diphenyl-2-picrylhydracyl (DPPH) and 2,2-Azinobis 3-ethyl benzothiazoline 6- sulfonic acid (ABTS) method while total phenolic content (TPC) was measured using Folin-Ciocalteu. Secondary metabolites were characterized using thin layer chromatography (TLC) and GC-MS. TLC plate visualization using UV light, DPPH, FeCl3 and vanillin-sulfuric acid reagents. The results showed that the extract fermented for nine days was able to inhibit the growth of P. aeruginosa and M. luteus at a concentration of 2 mg/mL. The highest antioxidant activity was found in the nine days fermented extract with an RSA value of 21.9% ± 0,0001 for DPPH and 12.53 % ± 0.002 for ABTS. Furthermore, the highest total phenolic content was found in the nine days fermented extract of 7.57 GAE/mg. The results of characterization using TLC showed the presence of phenolic compounds, terpenoids and antioxidants in fresh seaweed extracts, autoclaved fresh seaweed, three days of fermentation, six days and nine days. Based on this research, it can be seen that the addition of marine yeast starter H. werneckii SUCCY001 was able to increase the antibacterial and antioxidant activity of G. verrucosa.

Proximate composition and physicochemical properties of Red seaweed Hypnea valentiae (Turnur) and their potential of antioxidant activities

The present study focused on proximate composition, moisture, ash, lipid, protein, carbohydrate, dietary fiber and physicochemical properties to determine the water holding capacity, oil holding capacity, and water swelling capacity of H. valentiae red seaweed. The antioxidant properties of methanol extract were performed by superoxide and nitric oxide radical scavenging activity. The superoxide scavenging radical (50-250 μg/mL) was an inhibition of 89.06 ± 0.44μg/mL which is significantly higher than the standard ascorbic acid 75.67 ± 0.20μg/mL. Nitric oxide assay observed that (15-100 μg/mL) exhibited the maximum nitric oxide scavenging was 87.22 ± 0.80μg/mL which is significantly higher than the standard ascorbic acid 74.35 ± 0.67μg/mL. The results were establishing the potential of the seaweed was exploited the nutritional value and pharmaceutical applications.

Chromatographic Profile and Redox-Modulating Capacity of Methanol Extract from Seeds of Ginkgo biloba L. Originating from Plovdiv Region in Bulgaria.

Oxidative stress underlies the pathogenesis of many diseases, which determines the interest in natural substances with antioxidant properties. Ginkgo biloba L. leaves are well known and widely used in the pharmaceutical industry, but the therapeutic properties of the seeds are less studied. This study aimed to identify the chromatographic profile and to evaluate the antioxidant properties of methanol extract from seeds of G. biloba (GBSE). In the GBSE, flavonoids and terpenes were found as terpenes predominated. The GBSE antioxidant capacity determined by 2,2 azino-bis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) and 1-diphenyl-2-picrylhydrazyl (DPPH) methods were equal to 1.34% and 0.58% of the activity of reference substance Trolox, respectively. The results of the ferric reducing antioxidant power method showed that the effect of concentration 1 mg/mL (w/v) GBSE was equal to 7.418 mM FeSO4 used as a standard. The cupric reducing antioxidant capacity activity of the GBSE was found to be 215.39 µmol Trolox/g GBSE and is presented as Trolox equivalent. The metal chelation effect of 1 mg/mL (w/v) GBSE was equal to that obtained for 0.018 mM EDTA. In conclusion, GBSE showed a good ability to neutralize ABTS and DPPH radicals and could have a beneficial effect in pathological conditions with oxidative stress etiology.

UJI AKTIVITAS ANTIOKSIDAN EKSTRAK METANOL DAUN BELIMBING WULUH (Averrhoa bilimbi)

Belimbing wuluh leaves contain active substances such as flavonoids, saponins, tannins, sulfur, formic acid, peroxidase, calcium oxalate and potassium citrate. Tannins, flavonoids and saponins which have antibacterial activity. Many plants contain antioxidants, one of which is starfruit leaves (Averrhoa bilimbi). Antioxidants are substances that can neutralize free radicals so that atoms with unpaired electrons gain electron pairs. This study aims to determine the antioxidant activity of the methanol extract of star fruit (Averrhoa Blimbi) leaves. The maceration process was carried out on samples of star fruit leaves (Averrhoa Blimbi) and then extracted using methanol as a solvent to analyze the antioxidant activity contained in the leaves of star fruit (Averrhoa Blimbi) using methanol. UV-vis spectrophotometry method. The results of the research that has been carried out on UV-vis spectrophotometry with a wavelength of 517 and has been incubated for 30 minutes shows the IC50 value of the methanol extract of starfruit leaves (Averrhoa Blimbi) of 288.82 mg/mL. The conclusion of this study is the antioxidant properties of methanol extract. Belimbing wuluh leaves contain compounds that act as antioxidants.

Phytochemical composition and antioxidant properties of methanolic extracts of whole and dehulled Bambara groundnut (Vigna subterranea) seeds

The distribution of phytochemicals and their contribution to antioxidant potentials in whole and dehulled Bambara groundnut (BGN) seeds was evaluated. Whole BGN seeds were sorted using the testa and hilium colour and further grouped into whole and dehulled BGN seeds. Extractions of both whole and dehulled BGN seeds was done using methanol and the extracts assayed for total phenolics (TPC), flavanol, flavonol, anthocyanin content, oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP). Methanolic extract of whole BGN seed exhibited higher flavanol and flavonol content as well as significantly higher in-vitro antioxidant activities than dehulled BGN seeds. The TPC of whole BGN seed extract ranged from 3.6 to 11.0 GAE/g, while that of dehulled BGN ranged from 2.7 to 3.2 GAE/g. Identification of phenolics in whole and dehulled BGN seed extract using UPLC-qTOF-MS, revealed the presence of monoterpenoids (iridoids), phenolic acids, flavonoids and lignans. Bivariate correlations showed anthocyanin demonstrated weak positive correlation between flavanol, flavonol and ORAC for whole BGN seed extract; and negative correlation between flavanol, TPC, FRAP and ORAC for dehulled BGN. Aside the effect of dehulling, whole BGN seeds exhibited the presence of phytochemicals with beneficial properties for food and industrial application.

DETERMINATION OF PHYSICOCHEMICAL PARAMETERS AND ANTIOXIDANT PROPERTIES OF RHUS JAVANICA LINN.

Objective: The present work presents determination of physicochemical parameters of the leaves and the antioxidant properties of methanolic extract of leaves, fruits and bark of Rhus javanica L.
 Methods: The leaves of Rhus javanica L. was used for the determination of physicochemical parameters using standard protocol. The leaves, fruits and bark of the plant were extracted successively with petroleum ether, chloroform and methanol. The methanolic extracts were used to determine the antioxidant properties. The radical scavenging activity was determined with different methods like DPPH, hydrogen peroxide and hydroxyl radical scavenging assay. The reducing power was determined by reduction of ferric cyanide complex (Fe3+) to the ferrous cyanide form (Fe2+). Total phenols and flavonoids concentrations were analysed using Folin-Ciocalteu’s and aluminium chloride methods.
 Results: The moisture content, extractive value (alcohol and water), total ash, acid insoluble ash and water-soluble ash were 0.29%, 24.502%, 19.314%, 8.2%, 0.45% and 4.75% respectively. The fruit extract exhibits the highest scavenging activity presented as percentage inhibition, 75.00±0.89% (100 μg/ml) for DPPH free radical and 74.7±0.68% (100 μg/ml) for hydrogen peroxide radical. The standard BHT (100 μg/ml) shows 78.5±0.43% inhibition for DPPH free radical and 82.5±0.50% inhibition for hydrogen peroxide free radical. The leaves show the highest hydroxyl radical scavenging activity, 65.00±0.40% (100 μg/ml) while the standard Ascorbic acid exhibit 73.81±0.61% (100 μg/ml) inhibition. The highest reducing power was shown by the bark extract but lower than the standard Ascorbic acid. The bark extract shows the highest phenolic and flavonoid content 49.86 mg GAE/g and 19.38 mg QE/g respectively of the dry weight of the extract.
 Conclusion: The results of quantitative pharmacognostic parameters in this study is expected to be useful for setting standards for correct identification of the plant. The radical scavenging properties, total phenolic and flavonoid content also suggest that the extracts provide substantial antioxidant activities.

Evaluation of Antioxidant, Immunomodulatory and Anticancer Properties of Methanolic Extract of Neolamarckia cadamba Linn. Fruits

Abstract: Background: The immune system plays an important role in various diseased conditions. Patients with compromised immune function are at increased risk of exposure. Thus, the evaluation of immunomodulatory activity of plant extracts may be helpful for prophylactic treatment approach. Objectives: The aim of present study is to evaluate the effect of methanolic extract of Neolamarckia cadamba Linn. fruits for antioxidant, immunomodulatory and anticancer properties using in-vitro and in-vitro models. Methods: In the present investigation, antioxidant property of methanolic extract of Neolamarckia cadamba fruits (NCM) was evaluated by superoxide radical and DPPH scavenging activity. The immunomodulatory property of NCM extract was analysed by determining cytokines release (IL-2 and TNFα) in murine primary thymocytes. The effects of NCM extract on humoral and cellular immunity was analysed under in vivo conditions. The anticancer activity of the extract was evaluated on Jurkat J6 cell line by MTT assay. Results: The methanolic extract of Neolamarckia cadamba fruits showed superoxide and DPPH free radical scavenging antioxidant activity and significantly increased the cytokines release (IL-2 and TNFα) in murine primary thymocytes. The increased hemagglutination antibody titre and neutrophil adhesion as well as the restoration of cyclophosphamideinduced myelosuppression and DTH response confirm the stimulatory effect of NCM on T cells. In-vitro results on Jurkat J6 cell line showed the significant increase in cell death confirming its anticancer activity. Conclusion: Thus, it can be concluded that the methanolic extract of the fruits of Neolamarckia cadamba possesses antioxidant activity, immunomodulatory property as well as anticancer potential, suggesting its therapeutic efficiency in the treatment of immune disorders as well as cancer. Key words: Neolamarckia cadamba, Immunomodulatory, Antioxidative, Anticancer, Cytokines, Neutrophil adhesion.

Determination of Antimicrobial and Antioxidant Activity of Some Spices Widely Consumed in Turkey

In the present study, antimicrobial and antioxidant properties of methanol extracts of some packaged and unpackaged spices including cinnamon (Cinnamomum zeylanicum), cumin (Cuminum cyminum L.), thyme (Thymus vulgaris L.) and mint (Mentha spicata L.) were determined. The antimicrobial effect of different concentrations of these spice extracts was examined by agar diffusion method against Escherichia coli, Enterococcus faecalis, Bacillus cereus, Pseudomonas aeruginosa and Salmonella typhimurium. While the antioxidant properties of spice extracts were examined using 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) and 2,2-diphenyl-1-picryl-hydrazyl (DPPH) methods, the total phenolic components were examined using Folin–Ciocalteu method. Methanol extracts of spices showed antimicrobial activity at different rates against tested microorganisms. The methanol extract of unpackaged mint showed highest inhibiton zones (22.50 mm) against Salmonella typhimurium. When the total phenolic concentrations of spice extracts ranged from 6239.58 to 27197.92 mg GAE/kg, the ABTS values ranged from 40.75 to 667.57 mmol Trolox/g dried spice and the percentage of DPPH inhibitions ranged from 88.98 to 96.26%.

Total Phenolic, Flavonoid Contents, and Antioxidant Activities of Fruit, Seed, and Bark Extracts of Zanthoxylum armatum DC.

Natural antioxidants present in several medicinal plants are responsible for inhibiting the harmful effects of oxidative stress. These plants contain polyphenols and flavonoids that act as free radical scavengers and reduce oxidative stress and may be an alternative remedy to cure various harmful human diseases. This study aims to quantify the total phenolic and flavonoid contents (TPC and TFC) and antioxidant properties of methanol extracts of fruits, seeds, and bark of an important medicinal and aromatic plant, Zanthoxylum armatum collected from wild and cultivated populations in Nepal. TPC was determined by Folin–Ciocalteu colorimetric method using gallic acid as standard, and various concentrations of the extract solutions were measured at 760 nm. TFC was calculated by aluminum chloride colorimetric assay. Quercetin was used as standard, and the absorbance was measured at 510 nm. The antioxidant potential of the different extracts was estimated by DPPH free radical scavenging assay, and the absorbance was measured at 517 nm. The highest TPC value was 226.3 ± 1.14 mg GAE/g in wild fruits, and the lowest was 137.72 ± 4.21 mg GAE/g in cultivated seeds. Similarly, the highest TFC value was 135.17 ± 2.02 mg QE/g in cultivated fruits, and the lowest was 76.58 ± 4.18 mg QE/g in cultivated seeds. The extracts showed variable antioxidant properties. The fruits exhibited excellent antioxidant properties with IC50 values of 40.62 μg/mL and 45.62 μg/mL for cultivated and wild fruits, respectively. Similarly, the IC50 values of the bark were 63.39 μg/mL and 67.82 μg/mL, respectively, for cultivated and wild samples. And the least antioxidant capacity was shown by the seeds extract with IC50 values of 86.75 μg/mL and 94.49 μg/mL for wild and cultivated seeds, respectively. The IC50 value of the standard ascorbic acid was 36.22 μg/mL. Different extracts of Z. armatum contain considerable amount of phenols and flavonoids, including antioxidant properties, suggesting the potential use of this species in pharmacy and phytotherapy as a source of natural antioxidants.

The effect of different drying methods on chemical composition and antioxidant properties of methanolic extract of olive leaf

The effect of different drying methods on chemical composition and antioxidant properties of methanolic extract of olive leaf

Immunomodulatory and anticancer activity of Bombax ceiba Linn leaf extract

Objective: To evaluate the immunomodulatory and anticancer activity of the methanolic extract of Bombax ceiba leaves in vitro and in vivo. Methods: The antioxidant property of methanolic extract of Bombax ceiba leaves was determined by measuring hydrogen peroxide scavenging and DPPH scavenging activity. The effect on cellular immunity in vivo was determined by measuring neutrophil adhesion, carbon clearance, sheep red blood cell induced DTH response and cyclophosphamide-induced myelosuppression. In vitro anticancer activity was evaluated on human leukaemia cell line (HL-60) by MTT assay, caspase-3 activity, and cell cycle study. Results: The methanolic extract of Bombax ceiba leaves showed antioxidant activity and significantly increased neutrophil adhesion, carbon clearance from blood, DTH response and cyclophosphamide-induced myelosuppression. The MTT assay showed a significant increase in the death of HL-60 cell line. A rise in caspase-3 activity and sub-G1 population in the presence of methanolic extract of Bombax ceiba leaves was observed. Conclusions: The methanolic extract of leaves of Bombax ceiba L possesses anticancer activity, immunomodulatory activity, and antioxidant properties, proving its therapeutic usefulness in the treatment of immuno-compromised diseases and cancers.

Quantitative estimation of total phenols, total flavonoids, and antioxidant activity of methanolic extracts of Ephedra gerardiana Wall. ex Stapf across different habitats of cold desert biosphere reserve, trans Himalaya, India

The present study evaluated phenolic compounds and antioxidant properties of methanolic extracts of aerial part and root of a high altitude threatened species, Ephedra gerardiana Wall. ex Stapf (Fam: Ephedraceae). E. gerardiana was collected from five distantly located populations in Cold Desert Biosphere Reserve. The concentration of total phenolic contents was recorded in range between 110±3.5 to 132±2.52 (aerial part) and 135±0.6 to161±0.49 (root) mg GAE g−1 of extracts and flavonoid contents was recorded between 66±1.47 to 87±0.84 (aerial part) and 108±1 to 137±0.48 (root) mg QE g−1. Total phenolic contents were significantly higher in E. gerardiana population growing on river bed habitat. One way analysis of variance (ANOVA) revealed significant variation among populations. All extracts exhibited strong antioxidant activity. The percent inhibition was found to increase with every unit increase in concentration. The DPPH and ABTS radical scavenging reached up to 82.15% and 97.55% at a concentration of 400 μg mL−1, respectively. Reducing power was ranged from 0.198±0.001 to 0.597±0.005 at concentrations ranging from 50 to 400 μg mL−1. Therefore, present study results revealed that E. gerardiana is a natural source of antioxidant.

Antioxidant properties of methanolic extract of ‘Veronica multifida’ and DFT and HF analyses of its the major flavonoid component

The experimental part of this study, investigated the effects of a methanolic extract of Veronica multifida on total phenolic and flavonoid content, antioxidant capacities; and DPPH scavenging activity. The methanol extract of V. multifida showed an equivalent of phenolic content of 196.67 mg gallic acid per gram dry weight, flavonoid content of 206.17 mg quercetin per gram dry weight and total antioxidant capacities of 134.41 mM α-tocopherol acetate per gram dry weight. Additionally, the amount of extract supplying 50% inhibition of DPPH was assayed as 66.65 mg L−1. The V. multifida plant extract to be used in the study was reported to contain luteolin as its main flavonoid component. The luteolin content of 0.2–0.5 μg g−1 was reported to be within the normal concentration range. Additionally, the antioxidant properties of luteolin were theoretically examined and compared to butylated hydroxytoluene and curcumin, which are respectively synthetic and natural antioxidants. The density functional theory (DFT) and Hartree-Fock methods were used in all calculations. The most stable structures of molecules were determined by using the B3LYP functional with the 6-311G(d,p) basis set. The theoretical methods showed that the antioxidant properties of pure luteolin are similar to those of butylated hydroxytoluene.

Physicochemical and antioxidant properties of methanol extract from Maca (Lepidium meyenii Walp.) leaves and roots

Abstract In this study, we examined the phytochemical properties and antioxidant activities of the methanol extracts of maca (Lepidium meyenii Walp.) leaves and roots. A total of 25 chemical compounds were identified by LC-Q-TOF and classified as saponins, phenols, flavonoids, steroids, alkybenzenes, and amines. Among all the chemical compounds identified, three saponins (tanshinone I, panaxytriol, and rotundifolioside), one phenol (gingerol), and one steroid (ergosterol peroxide) were found in the both leaf and root extracts. Levels of saponins, phenols, and flavonoids in the methanol extract from maca leaves were significantly higher than in the extract of roots. Antioxidant activities (1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and ferric reducing ability of plasma) of the methanol extracts of maca leaves were higher than those of the roots. Antioxidant activities were highly correlated with total phenol content in the methanol extracts of maca leaves. Therefore, the methanol extract from maca leaves exhibited higher antioxidant activities than those of roots, and could be used as a nutritional material with potential health benefits.

Creosote Bush (Larrea tridentata) Extract Assessment as a Green Antioxidant for Biodiesel.

In this work, the antioxidant properties of methanolic extract of Larrea tridentata were assessed through the free radical scavenging method, ferric reducing antioxidant power and oxygen radical absorbance capacity. The phenolic acids content in the extract was quantified by high-performance liquid chromatography (HPLC) and the total phenol content by the Folin–Ciocalteu method. The extract was used as an antioxidant in biodiesel from canola oil composed mostly by fatty acid methyl esters identified and quantified by gas chromatography-mass spectrophotometry (GC-MS). The performance of the extract as an antioxidant was assessed by the oxidative stability index (OSI) with a Rancimat equipment at 100, 110, 120 and 130 °C. Additionally, the change of the peroxide value (PV) and the higher heating value under conditions of oxidative stress at 100 °C and air injection were measured. The antioxidant capacity of the extract reached 50,000 TAEC (micromole of Trolox antioxidant equivalent capacity per gram). The biodiesel was constituted by more than 70% of unsaturated fatty acid methyl esters (FAME), mainly methyl oleate. The time needed to reach a PV of 100 meqO2/kg was almost four times longer with an antioxidant concentration of 250 mg/L than the blank. The biodiesel showed an OSI time of 1.25 h at 110 °C, while it increased to 8.8, 15.89 and 32.27 h with the antioxidant at concentrations of 250, 500 and 1000 mg/L, respectively. The methanolic Larrea tridentata extract proved to have an antioxidant capacity and it is a green antioxidant in biodiesel to increase its oxidative stability. According to the results obtained, the L. tridentata methanolic extract is an alternative to the commercial synthetic antioxidants used in biodiesel nowadays.