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Piper betle leaf powder is increasingly utilised as a health supplement. In this study, P. betle leaves were subjected to four different drying methods: convective air-drying, oven-drying, sun-drying, and no drying, with fresh leaves as control. Their antioxidant properties were then evaluated using colourimetric assays and GC-MS. Results showed that the sun-dried leaves had the highest ( p < 0.05) total antioxidant capacity (66.23 ± 0.10 mg AAE/g), total polyphenol content (133.93 ± 3.76 mg GAE/g), total flavonoid content (81.25 ± 3.26 mg CE/g) and DPPH radical scavenging activity (56.48 ± 0.11%), and the lowest alkaloid content (45.684 ± 0.265 mg/gm). GC-MS analysis revealed that major constituents of aqueous extracts of fresh and sun-dried P. betle leaves were hydrazine 1,2-dimethyl-; ethyl aminomethylformimidate; glycerin; propanoic acid, 2-hydroxy-, methyl ester, (+/-)-; and 1,2-Cyclopentanedione. In conclusion, sun-dried leaves exhibited overall better antioxidant properties, and their aqueous extracts contained biologically active phytoconstituents that have uses in various fields.

Honeysuckle (Lonicera japonica flos) is a well-known agent of edible and medicinal value in China and its antioxidative activity makes a major contribution to its dual use. However, the compounds responsible for its antioxidative activity are still unknown. In this study, 10 batches of honeysuckle were collected from different origins in China. The fingerprints were established by HPLC technique to investigate the compounds and a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity assay was carried out to evaluate their antioxidant activity. partial least squares regression analysis was applied to set up the regression equation between DPPH radical scavenging activity and average peak area of common peaks of fingerprints. The results showed that peaks 10 (isochlorogenic acid B), 12 (isochlorogenic acid C), 11 (isochlorogenic acid A) and 9 (cynaroside) in the fingerprints were closely related to the antioxidant activity of 50% methanol extracts of honeysuckle. This study successfully established the spectrum-effect relationship between HPLC fingerprints and DPPH radical scavenging activity and provided a general model for exploring active components with a combination of chromatography and efficacy., (© 2019 John Wiley & Sons, Ltd.)

In this study, the extraction conditions for the maximum recovery of polyphenols with high antioxidant activity were optimised by response surface methodology (RSM) in Feronia limonia fruit. The independent variables were viz. concentration of ethanol (X1: 30-70%), incubation temperature (X2: 37-60%) and solvent-to-solid ratio (X3: 20-40%). ANOVA results showed that concentration of ethanol and temperature affected the total polyphenol content (TPC, Y1), DPPH (Y2) and ABTS (Y3) radical scavenging activities significantly (p<0.05) whereas solvent-to-solid ratio was found to be insignificant. A second-order polynomial model satisfactorily fitted the experimental data with the R(2) values of 0.966, 0.946 and 0.955, respectively for the responses Y1, Y2 and Y3 (p<0.0001), implying a good agreement between the predicted and experimental values. The optimal conditions for the highest yield of TPC (7.21±1.4 g GAE/g) with >80% radical scavenging activities were derived at X1=62.7%, X1=49.7 °C and X3=39.4 mL/g., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Eight new caffeoyl derivatives, elephantomentosides A–H (1 − 8), together with ten known ones (9 − 18), were isolated from the whole plant of Elephantopos tomentosus L. Their structures were elucidated using detailed spectroscopic analysis. Structurally, compounds 1 − 8 are composed of β-D-glucopyranose, and almost all of the substituent positions are at the C-1′ and C-4′ of glucopyranose. The anti-inflammatory and antioxidant activities of all isolated compounds were evaluated in vitro. Compounds 9–10, 13–15, and 17–18 exhibited significant DPPH scavenging capacity with IC50 values in the range of 10.01–25.07 μM, in comparison with Vc (IC50, 17.98 μM). [ABSTRACT FROM AUTHOR]

Objectives: The present work was aimed to determine the effect on the Phospholipase A2 (PLA2) enzyme and conduct its antioxidant nature, phytochemical analyses of the Triphala compound's extract, an Ayurvedic Rasayana made from Terminalia chebula, Emblica officinalis and Terminalia bellirica and also, the molecular docking study. Methods: Twelve Triphala compounds are extracted from Gas chromatography-mass spectrometry, Phytochemical study, the Triphala's inhibitory effect on antioxidant property and PLA2 assay. To study each compound's degree by docking software like iGEMDOCK, Auto dock Vina, and overlapping on the PLA2 enzymes like Naja naja, Human sPLA2, Bee and Scorpion venoms phospholipase. Results: Phytochemical screening revealed the presence of phenolics, alkaloids, saponins, flavonoids and tannins. Methanolic extract of Triphala fruit powder also showed good scavenging ability compared to the superoxide. IC50 value of seed powder extract is 23.12 µg/ml whereas standard, i.e. superoxide is at 32.66 µg/ml, respectively. IC50 scavenging activity was 31.18. µg/ml and 32.66 µg/ml standard, respectively. Moreover, it shows a better interaction of bioactive compounds with the PLA2 enzyme. Morin (3,5,7,2',5'-Pentahydroxyflavone) 9,10 anthraquinone was found to be a better inhibitor among the compounds, with a binding energy -82.6534K. cal/mol, -73.9662K.cal/mol respectively and hydrogen bonding with PRO-61 and ARG-59, the primary amino acid residues at the active site of PLA2. Conclusion: The study will allow the Triphala compounds that contain lead in oncological therapy and other inflammatory diseases to be improved. [ABSTRACT FROM AUTHOR]

Objectives: The present work was aimed to determine the effect on the Phospholipase A2 (PLA2) enzyme and conduct its antioxidant nature, phytochemical analyses of the Triphala compound's extract, an Ayurvedic Rasayana made from Terminalia chebula, Emblica officinalis and Terminalia bellirica and also, the molecular docking study. Methods: Twelve Triphala compounds are extracted from Gas chromatography-mass spectrometry, Phytochemical study, the Triphala's inhibitory effect on antioxidant property and PLA2 assay. To study each compound's degree by docking software like iGEMDOCK, Auto dock Vina, and overlapping on the PLA2 enzymes like Naja naja, Human sPLA2, Bee and Scorpion venoms phospholipase. Results: Phytochemical screening revealed the presence of phenolics, alkaloids, saponins, flavonoids and tannins. Methanolic extract of Triphala fruit powder also showed good scavenging ability compared to the superoxide. IC50 value of seed powder extract is 23.12 µg/ml whereas standard, i.e. superoxide is at 32.66 µg/ml, respectively. IC50 scavenging activity was 31.18. µg/ml and 32.66 µg/ml standard, respectively. Moreover, it shows a better interaction of bioactive compounds with the PLA2 enzyme. Morin (3,5,7,2',5'-Pentahydroxyflavone) 9,10 anthraquinone was found to be a better inhibitor among the compounds, with a binding energy -82.6534K. cal/mol, -73.9662K.cal/mol respectively and hydrogen bonding with PRO-61 and ARG-59, the primary amino acid residues at the active site of PLA2. Conclusion: The study will allow the Triphala compounds that contain lead in oncological therapy and other inflammatory diseases to be improved. [ABSTRACT FROM AUTHOR]

Japanese mint (Mentha arvensis) is a widely used herb for culinary, fragrant, and medicinal applications. In this study, useful substances were obtained from Japanese mint leaves by extraction using subcritical water (180 to 260 °C). The characteristics of the mint extracts, including carbohydrates, proteins, and phenolic content, as well as 2',2'-diphenyl-1-picryhydrazyl (DPPH) radical scavenging activity were investigated. The highest carbohydrate content was obtained at 180 °C, while the highest amount of protein was obtained at 200 °C. A linear relationship was observed between the phenolic content and DPPH radical scavenging activity. Oligosaccharide was the most abundant sugar in the extracts, as determined by high performance liquid chromatography analysis. The presence of apocynin, a potent non-steroidal anti-inflammatory drug, was identified by gas chromatography-mass spectrometry and its content showed an exponential increase as the temperature was increased from 180 to 260 °C. This study provides practical information for applications of Japanese mint. [ABSTRACT FROM AUTHOR]

The macerated methanolic extract of P. vera L., A. strigosa and I. paraguariensis A. St.-Hil. were used for evaluating their antioxidant activity. The results of present study showed that the IC50 value for Pistacia vera L., Anchusa strigosa and Llex paraguariensis A. St.-Hil. extracts were 5.85 ± 0.11, 43.75 ± 1.05 and 8.98 ± 0.65μg/ml respectively compared to 1.48 ± 0.05 μg/ml of ascorbic acid against DPPH radical. The IC50 values for β-carotene bleaching (BCB) assay for P. vera L., A. strigosa and I. paraguariensis A. St.-Hil. extracts were 390.1 ± 7.5, 425.8 ± 6.5 and 410.2 ± 9.0 μg/ml respectively compared to 9.5 ± 0.4 μg/ml of rutin. The results of β-carotene bleaching (BCB) assay showed that the plant extract exhibits weak activity compared to rutin. In conclusion, the present study indicates that these plants and their phytochemical constituents can be exploited in future extensively for controlling oxidative stress and ailments. [ABSTRACT FROM AUTHOR]

Background: Lantana camara L. leaves have been traditionally claimed to be used in treatment of different illnesses. Leaves are rich in lower terpenes in the form of essential oil, however they also contain lipids like waxes. Both classes, lipids and terpenes are soluble in petroleum ether, but only lipids can be saponified, not terpenes. Aim: The present study was aimed towards preparation of unsaponified terpene-rich extract of L. camara L. leaves; its assessment for anti-oxidant activity and capacity to impart oxidative stability. Methods: In order to remove lipids and retain terpenes, in present study, petroleum ether extract of Lantana camara L. leaves was saponified using aqueous potassium hydroxide and unsaponified matter was standardized using β-caryophyllene as marker; screened for anti-oxidant activity, using DPPH radical scavenging model and estimated for its capacity to impart oxidative stability using Rancimat test. Results: Tested extract showed considerable antioxidant activity (IC50 value:13 µg/ml) and imparts 74.83% protection against oxidation as compared to standards used. Conclusion: Lipids can be removed by saponification and thereby, petroleum ether extract can be made rich in terpenes. This unsaponified petroleum ether extract of L. camara L. leaves shows better antioxidant results as compared to petroleum ether extract and comparable with standards used. [ABSTRACT FROM AUTHOR]

A new triterpenoid, namely myricarin C (compound 1), together with three known compounds myricarin A (compound 2) and myricarin B (compound 3), 3α-hydroxy-D-friedoolean-14-en-28-oic acid (compound 4), was isolated from the overground part of Myricaria squamosa. Compound 2 and compound 3 existed in the solution by the form of cis-trans isomers. Their structures were elucidated by means of extensive spectroscopic methods, including 1D-NMR, 2D-NMR, and HR-ESI-MS. The antioxidant properties of all compounds were calculated based on the DPPH radical scavenging activities. Results showed that myricarin A and myricarin C had general antioxidant activities with EC50 values of 40.90 μg/ml, 42.22 μg/ml, respectively, compared to the control, rutin (5.17 μg/ml). The EC50 values of myricarin B was 195.81 μg/ml. Compound 4 had no antioxidant activities. [ABSTRACT FROM AUTHOR]

Background: Lantana camara L. leaves have been traditionally claimed to be used in treatment of different illnesses. Leaves are rich in lower terpenes in the form of essential oil, however they also contain lipids like waxes. Both classes, lipids and terpenes are soluble in petroleum ether, but only lipids can be saponified, not terpenes. Aim: The present study was aimed towards preparation of unsaponified terpene-rich extract of L. camara L. leaves; its assessment for anti-oxidant activity and capacity to impart oxidative stability. Methods: In order to remove lipids and retain terpenes, in present study, petroleum ether extract of Lantana camara L. leaves was saponified using aqueous potassium hydroxide and unsaponified matter was standardized using β-caryophyllene as marker; screened for anti-oxidant activity, using DPPH radical scavenging model and estimated for its capacity to impart oxidative stability using Rancimat test. Results: Tested extract showed considerable antioxidant activity (IC50 value:13 µg/ml) and imparts 74.83% protection against oxidation as compared to standards used. Conclusion: Lipids can be removed by saponification and thereby, petroleum ether extract can be made rich in terpenes. This unsaponified petroleum ether extract of L. camara L. leaves shows better antioxidant results as compared to petroleum ether extract and comparable with standards used. [ABSTRACT FROM AUTHOR]

The objective of the present research work was to evaluate the antioxidant, antimicrobial and antimalarial activities of essential oil and various extracts fromO. sanctum. Gas chromatography-mass spectrometry analysis identified the following major compounds with their quantification as: eugenol (22.0%), β-elemene (19.2%), β-caryophyllene (19.1%), and Germacrene D (5.03%). HPLC analysis ofO. sanctumextracts revealed that gallic acid, chlorogenic acid,p-hydroxy benzoic acid, caffeic acid, vanillic acid,p-coumeric acid, sinapic acid, and ferulic acid were the important phenolic acids. The methanol extract exhibited highest level of total phenolic (1.36 g/100 g dry plant material) and total flavonoid (0.67 g/100 g dry plant material) followed by ethanol andn-hexane extracts. The oil and extracts exhibited excellent free radical scavenging potential as measured by 2,2-diphenyl-1-picrylhydrazyl radical free radical-scavenging ability, and antioxidant activity as measured by inhibition of linoleic acid oxidation. Essential oil,n-hexane, methanol, and ethanol extracts exhibited moderate antimalarial potential in term of anti-haem biocrystallization activity. In the resazurin microtitre plate and disc diffusion assays, the essential oil ofO. sanctumshowed better antibacterial activity than various extracts. The results of the present investigation demonstrated significant (p< 0.05) variations in the antioxidant, antimicrobial, and antimalarial activities of essential oil and extracts fromO. sanctum. [ABSTRACT FROM AUTHOR]

Five new ursane-type triterpenoidal saponins ( 1 – 5 ), together with five known ones ( 6 – 10 ), were isolated from the EtOH extract of the roots of Ilex cornuta . The structures of saponins 1 – 5 were elucidated as 19 α -hydroxyurs-12-en-28-oic acid 3 β -O- β -D-glucuronopyranoside ( 1 ), 19 α -hydroxyurs-12-en-28-oic acid 3 β -O- β -D-glucuronopyranoside-6-O-ethyl ester ( 2 ), 19 α -hydroxyurs-12-en-28-oic acid 3 β -O- α -L-arabinopyranosyl-(1 → 2)- β -D-glucuronopyranoside ( 3 ), 3 β -O-[ α -L-arabinopyranosyl-(1 → 2)- β -D-glucuronopyranosyl]-19 α -hydroxyurs-12-en-28-oic acid 28-O- β -D-glucopyranosyl ester ( 4 ) and 3 β -O-[ α -L-arabinopyranosyl-(1 → 2)- β -D-glucuronopyranoside-6-O-methyl ester]-19 α -hydroxyurs-12-en-28-oic acid 28-O- β -D-glucopyranosyl ester ( 5 ), on the basis of spectroscopic analyses (IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR) and chemical reactions. Protective effects of compounds 1 – 10 against H 2 O 2 -induced H9c2 cardiomyocyte injury were tested. Compounds 1 – 5 , 7 , and 10 showed cell-protective effects. Among them compound 5 exhibited the highest activity. No significant DPPH radical scavenging activity was observed for compounds 1 – 10 . [ABSTRACT FROM AUTHOR]

A phytochemical investigation on the ethyl acetate soluble fraction of Zanthoxylum armatum led in the isolation of two new prenylated alkaloids 2,6,7-trimethoxy-8-(3-methyl-2-butenyl)carbazole-3-carbaldehyde (1) and methyl-2,6,7-trimethoxy-8-(3-methyl-2-butenyl)carbazole-3-carboxylate (2), along with three known lignans cisamin (3), methyl pirpirtol (4), and fargesin (5) and one known alkaloid dictamine (6). Their structures were established on the basis of spectroscopic and crystallographic analysis and by comparison of the data with those in the literature. All the isolated compounds were screened for the DPPH free radical scavenging activity. Compounds 1, 2, and 6 showed profound activity while compounds 3–5 showed moderate activity. [ABSTRACT FROM AUTHOR]

In this study, antioxidant potentials of persimmon peel extracted with different levels of ethanol (0 [DW], 50, 70, and 99%) were screened for their antioxidant activity at various concentrations. The persimmon peel extracted by 70% ethanol inhibited 89.82% of 1,1-diphenyl-2-picrylhydrazyl radical at 0.5 mg/mL and had β-carotene bleaching inhibition activity at values of 91.26%. superoxide dismutase-like activity and reducing power had the highest in persimmon peel extracted by 70% ethanol each at 0.5 mg/mL and 1 mg/mL and the lowest persimmon peel extracted by distilled water. These results provided that persimmon peel extracted by 70% ethanol could be the most effective as a natural antioxidant in food industry. [ABSTRACT FROM PUBLISHER]

A new 9,10-dihydrophenanthrene derivative, monbarbatain E ( 1), together with 10 known bibenzyl or phenanthrene derivatives, were isolated from the acetone extract of the rhizomes of Monomeria barbata Lindl. The new compound was identified as 4-O-[4″-(5′-hydroxy-3′,3″-dimethoxybibenzyl)]-1,7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene on the basis of extensive spectroscopic investigations (HR-ESI-MS, 1D and 2D NMR). Compounds 1 and 2 were evaluated for their cytotoxic effects, and compounds 2-5 were tested for their antioxidant activities. Compounds 1 and 2 exhibited medium cytotoxic activity against HL-60 and Skov-3 cell lines. Compounds 2-5 showed significant DPPH radical scavenging activities. [ABSTRACT FROM AUTHOR]

The medicinal herbs, a valuable source of biologically active compounds, have been used in folk medicine for various diseases, but phytochemical exploration is still incomplete. This study presents the extractive technological processes and spectrophotometric characterization of threeindigenous plants in order to obtain anantifungal formula with applications inhorticulture.Therefore, it was evaluated the antioxidant activity, total phenolic (TPC) and flavonoid contents (TFC) and the correlation between them for individual extracts obtained by two different methods: Soxhlet (S) and percolation (P).The obtained data showed a significant difference both between the plant material used, as well as the extraction method applied. Most of the extracts prepared by Soxhlet method had higher antioxidant properties and phenolic contents than the ones obtained by percolation. Based on the results, were elaborated five association formulas, of which Rosmarinus officinalisL. combination 1:1 (S: P) showed the best results:TPC - 236.38 mg GAE / g DW, TFC - 247.11 mg rutin / g DW, EC50 - 0.030 mg/mL. [ABSTRACT FROM AUTHOR]

The effects of conventional (CV) and microwave (MW) heating on total soluble solid (TSS) content, total anthocyanin content (TAC), total phenolic content (TPC) and antioxidant activity of raspberry juice obtained from two cultivars of Amol (AM) and Siyahkal (SK) were scrutinised. Antioxidant activity of the juices was measured by 2,2 diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity and expressed as EC50 value. In the both methods, the concentration rate constant for the juices was significantly decreased by increasing operational pressure from 12 to 100 kPa ( P < 0.05). A first-order reaction kinetic model was successfully fitted for the degradation of monomeric anthocyanins at all operating pressures. The results also showed that thermal treatment of MW compared CV in both SK and AM cultivars caused a lower decrease in the TAC, TPC and antioxidant activity. Moreover, the changes in trend of the antioxidant activities due to the thermal treatment were positively correlated with the TPC ( r = 0.74, P < 0.05) and TAC ( r = 0.61, P < 0.05). [ABSTRACT FROM AUTHOR]

Abstract: An alkaloid with novel skeleton, sinoscrewtine (1), has been isolated from the roots of Sinomenium acutum. Its structure was established by spectral analysis and X-ray crystallographic study, and its possible biosynthetic pathway was delivered. In vitro experiments, 1 showed weak injurious effects against H2O2/Aβ25–35 induced oxidative injury in PC-12 cells and DPPH radical scavenging activity with IC50 of 32.6μM. [Copyright &y& Elsevier]

Abstract: Ethnopharmacological relevance: There is an increase in antimicrobial resistance and complexities arising from verotoxic related bacterial infections as well as rise in demand for application of natural antioxidants to combat oxidative damage by free radicals in many oxidative stress-mediated disease conditions such as cancer. Thus the potential of Curtisia dentata as antimicrobial, antioxidant and antiverotoxin against environmental isolates of Escherichia coli and Acinetobacter spp. as well as the presence of phytochemicals and some organic compounds, was determined. Materials and methods: Phytochemical analysis was carried out using standard methods and antioxidant activity was determined using the DPPH radical scavenging activity. Effect of extracts on bacterial cell wall was also determined. Results: Extracts contained anthraquinones, alkaloids, essential oils, glycosides, phenols, steroids, saponins, tannins, quinones, anthocyanins, amines and carboxylic acids as phytochemicals. Extracts demonstrated high antimicrobial activity and low minimum inhibitory concentrations as well as inhibitory action against the expression of both Vtx1 and Vtx2 genes in Escherichia coli, Acinetobacter haemolyticus and Acinetobacter lwoffii. Ethanol root bark extracts consistently showed the highest DPPH radical scavenging activity (62.43%), total phenol content (TPH) (57.62 26mg GAE/g) and reducing power (RP) (41.32%), followed by those of the stem bark and leaf extracts with the respective values of 54.68%, 37.77mg GAE/g and 21.83%. The extracts induced the leakage of Na+ and K+ ions from both test bacteria. Conclusion: Curtisia dentata is a very effective source of antioxidant and a possible alternative to sourcing antiverotoxic antibiotics with novel mechanism of action. [Copyright &y& Elsevier]

Abstract: Extracts from aerial parts and roots of Tanacetum L. (emend. Briq.) chiliophyllum (Fisch. & Mey.) var. monocephalum Grierson from Turkey were investigated for their DPPH scavenging activity and contact toxicity against Sitophilus granarius. The ethyl acetate extract of aerial parts yielded a new sesquiterpene lactone 1-epi-chiliophyllin (1) which is a derivative of the compound chiliophyllin previously isolated from T. chiliophyllum var. heimerlei. Also known compounds; neolupenyl acetate (lup-12-ene-3β-acetate) (2), 4′,5,7-trihydroxy-3′,8-dimethoxyflavone (3), 4′,5,7-trihydroxy-8-methoxyflavone (4) were isolated together with (1). Structures of the compounds were determined by spectral methods including UV, IR, MS and 1D, 2D NMR. Highest contact toxicity against the stored granary products pest S. granarius was observed after 48h (68.49±0.67%). Highest DPPH scavenging activity observed for ethyl acetate extract of the roots at 10mg/mL concentration (87.8±0.84%). The DPPH scavenging activities of the pure flavonoids (3,4) at 1mg/mL concentration were unsignificant (3, 16.4±0.16%; 4, 17.6±0.82%) when compared with the positive controls α-tocopherol (91.7±1.07%) and BHT (91.7±0.37%) at the same concentration. [Copyright &y& Elsevier]

The present study determined some biological compounds (fatty acids, vitamins, sterols and flavonoids), radical scavenging capacity and antimicrobial activity of two Origanum L. species of Origanum vulgare L. subsp. gracile (C. Koch) Ietswaart and Origanum acutidens (Hand.-Mazz.). Ietswaart. Linolenic acid was found to be the main fatty acid in both species, which was followed by palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1 n9), linoleic acid (C18:2 n6) and stearidonic acid (C18:4). In addition, the two Origanum species were recorded as containing high levels of stigmasterol. It was also found that Origanum vulgare L. subsp. gracile (C. Koch) Ietswaart had a high β-sitosterol content (152.8 ± 2.6 µg/g); high amounts of D3 (33.1 ± 0.8 µg/g), K1 (29.4 ± 0.8 µg/g), K2 (26.0 ± 0.8 µg/g) vitamins; and low amounts of α-tocopherol (7.8 ± 0.2 µg/g) and D2 (1.8 ± 0.1 µg/g), while Origanum acutidens (Hand.-Mazz.) Ietswaart contained high amounts of D2 (42.9 ± 1.5 µg/g) vitamin; and low amounts of D3 (2.9 ± 0.1 µg/g), α-tocopherol (3.1 ± 0.1 µg/g), γ-tocopherol (3.5 ± 0.2 µg/g), K2 (1.3 ± 0.1 µg/g), retinol (1.3 ± 0.2 µg/g) and retinol acetate (1.2 ± 0.1 µg/g) vitamins. The present study showed that Origanum vulgare L. subsp. gracile (C. Koch) Ietswaart and Origanum acutidens (Hand.-Mazz.) Ietswaart contained the lowest amount of flavonoid. Furthermore, methanol extracts were recorded to be the most effective agent against the DPPH radical in both Origanum L. species examined. Experimental results showed that the vitamins, flavonoids and fatty acid extracts of both Origanum L. species were effective in the inhibition of the growth of the tested microorganisms at varying levels. [ABSTRACT FROM AUTHOR]

Abstract: An efficient microwave-assisted extraction (MAE) technique was employed to extract total phenolics (TP) from sweetpotato [Ipomoea batatas (L.) Lam.] leaves (TPSL). The optimal conditions for microwave-assisted extraction of TPSL were determined by response surface methodology. A face-centered cubic design (FCD) was applied to evaluate the effects of three independent variables (microwave power, extraction time and ethanol proportion) on the recovery of TPSL. The correlation analysis of the mathematical-regression model indicated that quadratic polynomial model could be employed to optimize the microwave extraction of TPSL. From response surface plots, microwave power, extraction time and ethanol proportion exhibited independent and interactive effects on the extraction of TPSL. The optimal conditions to obtain the highest recovery of TPSL were as follows: microwave power, 302W; extraction time, 123s; ethanol proportion, 53% (v/v). Under these optimal conditions, the experimental values agreed with the predicted ones by analysis of variance. It indicated high fitness of the model used and the success of response surface methodology for optimizing TPSL extraction. After method development, the antioxidant activity of the MAE extract was preliminarily evaluated. MAE showed obvious advantages in terms of high extraction efficiency and antioxidant activity of extract with in shortest extraction time. Industrial Relevance: Sweet potato leaves have been neglected except for a partial use as livestock feed in China. This study describes the response surface optimization of microwave-assisted extraction (MAE) process for the enhanced recovery of total phenolics from sweetpotato leaves (TPSL). MAE showed obvious advantages in terms of high extraction efficiency and antioxidant activity of extract within shortest extraction time. TPSL obtained using MAE showed potential for use in health-care food and pharmaceutical industry. [Copyright &y& Elsevier]

This study determined some biological compounds (fatty acid compositions, lipid-soluble vitamins, sterols, flavonoids), radical scavenging capacities and antimicrobial activities in the seeds of Nepeta italica L. and Sideritis montana L. subsp. montana. It was found that palmitic acid (C16:0; 8.54±0.13-3.05±0.04%), oleic acid (C18:1 n9, 22.41±0.8-18.83±0.1%) and α-linolenic acid (C18:3 n3;39.56±0.67-77.04±2.07%) were the dominant fatty acids in both Nepeta italica L. and Sideritis montana L. subsp. montana. It was concluded that both Nepeta italica L. and Sideritis montana L. subsp. montana contained stigmasterol (630.07±1.81µg/g, 80.74±0.71µg/g, respectively) and ergosterol (1.11±0.14µg/g, 161.32±0.63µg/g respectively) as well as beta-sitosterol (2.93±0.03 µg/g). The present findings show that Nepeta italica L. contains morin (37.79±1.09µg/g), catechin (124.39±2.23µg/g), naringin (475.96±3.57µg/g) and Sideritis montana L. subsp. montana contains morin (188.41±2.53µg/g), catechin (64.14±1.86µg/g), naringenin (38.34±1.78µg/g) as major flavonoids. It was also determined that methanol extracts of Nepeta italica L. and Sideritis montana L. subsp. montana were most effective against DPPH radicals. The results of the present study show that the vitamins, flavonoids and fatty acid extracts in the seeds of N. italica L. and S. montana L. subsp. montana prevented the growth of the microorganisms used in the tests at different ratios. [ABSTRACT FROM AUTHOR]

The aim of this study is to determine the total phenolic content and primary antioxidant activity of methanolic and ethanolic extracts of four aromatic plants' leaves namely knotweed (Polygonum minus), curry (Murraya koenigii), kafir lime (Citrus hysrix) and fragrant screwpine (Pandanus odurus). Total phenolic content (TPC) assay using Folin-Ciocalteu method was used to assess the presence and level of phenolic compounds in each sample. The present study showed that both methanolic and ethanolic extracts of P. minus had the highest TPC and followed by M. koenigii, C. hystrix and P. odorus. Primary antioxidant activity in terms of free radical scavenging activities of both methanolic and ethanolic extracts was then measured by 2, 2, diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity assay. The lowest EC50 values based on the DPPH radical scavenging activity were shown by P. minus extracts as compared to the other samples. For both ethanolic and methanolic extracts, the correlations between TPC and EC50 based on the DPPH radical scavenging activity assay were negative and weak. Relatively, the present results suggest that of the four aromatic plants, P. minus and M. koenigii have shown potential as sources of natural antioxidants. [ABSTRACT FROM AUTHOR]

Abstract: To investigate the antioxidant properties of commercial wild rice, identify and quantify soluble and insoluble phenolic acids in wild rice whole grain, the alkaline hydrolysates from crude methanol extracts (soluble fraction) and residues (insoluble fraction) were separately analysed by high performance liquid chromatography (HPLC) coupled with photodiode array detection (PAD) and quadrupole-time of flight (Q-TOF) mass spectrometry (LC–MS). The antioxidant activity of wild rice methanol extract was found to be up to 10 times greater than that of white rice (control sample) according to their 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and oxygen radical absorbance capacity (ORAC). Ferulic acid was found as the most abundant phenolic acid (up to 355mg/kg) followed by sinapic acid in wild rice. They both occurred mainly in the insoluble form. Other monomeric phenolic acids present in wild rice consisted of p-coumaric, vanillic, syringic, and p-hydroxybenzoic acids, along with two phenolic acid aldehydes (p-OH-benzaldehyde and vanillin). They were present in both soluble and insoluble forms. Phenolic acid dehydrodimers are cell wall bound and only appeared in the insoluble fractions featured by diferulic acids (DiFA) and disinapic acids (DiSA). The chemical structures of DiFA included 8-8′, 5-5′, 8-O-4′, and 8-5′ (benzofuran form) coupled dimers, with 8-O-4′ as the predominant form (up to 34mg/kg). DiSA only appeared as 8-8′-coupled products with the linear isomers in the most quantities (up to 19mg/kg). The DPPH free radical scavenging activities of soluble and insoluble fractions suggest that the antioxidant activity of wild rice is partially attributed to its phenolic acid profile. [Copyright &y& Elsevier]

The total polyphenol content and the antioxidant activities of curry leaf extracts (Hexane, Chloroform, Ethanol, Water and Aqueous(50%) ethanol) at ambient and hot conditions, were determined by DPPH, ABTS, and TRP assays. The total phenolic content was in the order EW1>W1>C1>EW2>H1>E2>W2>H2. It was observed that the EW1 had the maximum total phenolic content of 50.1% and 82% RSA at 10 μg/ml level (DPPH) and100% RSA (ABTS) at 10μg/ml and at hot conditions (EW2) had less TPC(28.7%),and 43% RSA by DPPH and 53.6% by ABTS assays. Other hot extracts had fewer activities than ambient extracts. The study showed that extracts at ambient temperature had higher antioxidant activity. [ABSTRACT FROM AUTHOR]

Abstract: In the current work, our target was to screen inhibitory potentials of 55 Turkish Salvia taxa, 28 of which are endemic, against acetylcholinesterase (AChE), which is a chief enzyme in pathogenesis of Alzheimer’s disease (AD). The dichloromethane, ethyl acetate, and methanol extracts prepared from 55 Salvia taxa were tested for their AChE inhibitory activity at 25, 50, and 100μg/ml using an ELISA microplate reader. The extracts were also screened for their scavenging effect against DPPH radical and iron-chelating capacity. Total phenol and total flavonoid contents of Salvia fruticosa were determined. Among the 165 Salvia extracts screened, only the dichloromethane extract of S. fruticosa showed inhibition towards AChE at 100μg/ml having 51.07% of inhibition, while only the dichloromethane and ethyl acetate extracts of Salvia cilicica had a notable iron-chelating capacity at 100μg/ml having 54.71% of chelating capacity. Most of the extracts showed remarkable scavenging effect against DPPH radical. [Copyright &y& Elsevier]

Abstract: Screening of potential antioxidant activities of water and 70% acetone extracts from ten species of Icelandic seaweeds was performed using three antioxidant assays. Significant differences were observed both in total phenolic contents (TPC) and antioxidant activities of extracts from the various species evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, oxygen radical absorbance capacity (ORAC) and ferrous ion-chelating ability assays. Acetone extracts from three Fucoid species had the highest TPC and consequently exhibited the strongest radical scavenging activities. High correlation was found between TPC of seaweed extracts and their scavenging capacity against DPPH and peroxyl radicals, indicating an important role of algal polyphenols as chain-breaking antioxidants. However, water extracts generally had higher ferrous ion-chelating activity than 70% acetone extracts and no correlation was found with their TPC, suggesting that other components such as polysaccharides, proteins or peptides in the extracts were more effective chelators of ferrous ions than phenolic compounds. [Copyright &y& Elsevier]