Research on the antioxidant activity of metabolites from a sponge-derived fungus Alternaria sp. F49 / 药学学报

To study the chemical constituents from the the deep-sea fungus Alternaria sp. F49. Seven compounds were isolated from the EtOAc extract by using silica gel, Sephadex LH-20, ODS and HPLC methods. Based on the spectroscopic analysis, their structures were identified as (8R)-5-O-methyl-orcinotriol (1), orcinotriol (2), α-acetylorcinol (3), 3'-hydroxyalternariol 5-O-methyl ether (4), altenusiol (5), altenusin (6), and 5'-methoxy-6-methyl-biphenyl-3,4,3'-triol (7). (8R)-5-O-Methyl-orcinotriol (1) is a new phenolic compound which has never been reported in the literature. Compounds 4-7 showed strong DPPH free radical scavenging activity; whereas compounds 1-7 showed strong ABTS free radical scavenging activity.

Quality Evaluation of Brown Rice Sulgidduk Containing Acorn Powder

This study examined the quality characteristics of brown rice Sulgidduk containing acorn powder and the optimal mixing rate (0%, 5%, 10%, and 15%). The moisture contents of brown rice Sulgidduk increased with increasing amount of acorn powder. The DPPH free radical scavenging activities (16.15%~28.06%) and ABTS free radical scavenging activities (22.98%~42.81%) of the brown rice Sulgidduk increased with increasing acorn powder content. The L value of the Hunter's color value decreased with increasing amount of acorn powder. The hardness and chewiness of brown rice Sulgidduk increased with increasing amount of acorn powder. The brown rice Sulgidduk containing 10% acorn powder showed the highest score with regard to the sensory characteristics. These results suggest that the most desirable amount of acorn powder is 10% and the addition of acorn powder could contribute positively toward the quality characteristics of brown rice Sulgidduk.

Spectrum-effect relationship between HPLC fingerprint and free radicals scavenging in Guizhi Shaoyao Zhimu Decoction / 中国中药杂志

To establish the spectrum-effect relationship between HPLC fingerprint and free radicals activity scavenging in Guizhi Shaoyao Zhimu Decoction( GSZD),and provide a basis for the quality evaluation and modernization of classical prescriptions. Shimadsu GL-science C18 column( 4. 6 mm×250 mm,5 μm) was used with acetonitrile-0. 1% formic acid solution as the mobile phase for gradient elution. The detective wave length was 254 nm; the column temperature was set at 32 ℃; the injection volume was 20 μL; and the flow rate was 1. 0 m L·min-1.10 batches of primary standard samples of GSZD were detected,and their HPLC fingerprint was established by using the similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine( TCM). The activity of scavenging free radicals was studied by 1,1-diphenyl-2-trinitrophenylhydrazine( DPPH) method,and the spectrum-effect relationship was studied by Pearson bivariate correlation analysis. The common mode of GSZD fingerprints was established,and 26 common peaks were marked,with similarities ranging from 0. 929 to 0. 998. Eight of the chromatographic peaks were identified by using the control comparison method: gallic acid,mangiferin,paeoniflorin,glycyrrhizin,asparagus,5-O-methylvisamicin,cinnamic acid,and ammonium glycyrrhetate. Among them,the content changes of No. 14( paeoniside),20,12( mangiferin),13 and 23( cinnamic acid) common peaks were negatively correlated with free radical scavenging activity. The fingerprint showed high precision,repeatability and stability,and the common peaks were well separated,so it can be used for the quality evaluation of GSZD,and could provide reference for further studies on the material basis of GSZD.

Optimization of subcritical aqueous extraction for polysaccharides from Punica granatum leaves and the in vitro antioxidant activity / 中成药

AIM To optimize the subcritical aqueous extraction for polysaccharides from the leaves of Punica granatum L.and to evaluate the in vitro antioxidant activity.METHODS With reaction pressure,solid-liquid ratio,extraction time and extraction temperature as influencing factors,yield of polysaccharides as an evalution index,the extraction was optimized by Box-Behnken method on the basis of single factor test.Then the scavenging effects of polysaccharides on hydroxyl free radical,superoxide anion and DPPH free radical were detected.RESULTS The optimal conditions were determined to be 5 MPa for reaction pressure,1 ∶ 27 for solid-liquid ratio,11 min for extraction time,and 155 ℃ for extraction temperature,the yield of polysaccharides was 1.809％.There was a dose-effect relationship between scavenging rate and polysaccharides' concentration.0.1 mg/mL Polysaccharides displayed the strongest scavenging effects on hydroxyl free radical,superoxide anion and DPPH free radical with the clearance rates of 57.36％,70.51％ and 58.02％,respectively.CONCLUSION This stable and reliable method can be used for the subcritical aqueous extraction for polysaccharides from P.granatum leaves with obvious in vitro antioxidant activity.

Optimization of subcritical aqueous extraction for polysaccharides from Punica granatum leaves and the in vitro antioxidant activity / 中成药

AIM To optimize the subcritical aqueous extraction for polysaccharides from the leaves of Punica granatum L.and to evaluate the in vitro antioxidant activity.METHODS With reaction pressure,solid-liquid ratio,extraction time and extraction temperature as influencing factors,yield of polysaccharides as an evalution index,the extraction was optimized by Box-Behnken method on the basis of single factor test.Then the scavenging effects of polysaccharides on hydroxyl free radical,superoxide anion and DPPH free radical were detected.RESULTS The optimal conditions were determined to be 5 MPa for reaction pressure,1 ∶ 27 for solid-liquid ratio,11 min for extraction time,and 155 ℃ for extraction temperature,the yield of polysaccharides was 1.809％.There was a dose-effect relationship between scavenging rate and polysaccharides' concentration.0.1 mg/mL Polysaccharides displayed the strongest scavenging effects on hydroxyl free radical,superoxide anion and DPPH free radical with the clearance rates of 57.36％,70.51％ and 58.02％,respectively.CONCLUSION This stable and reliable method can be used for the subcritical aqueous extraction for polysaccharides from P.granatum leaves with obvious in vitro antioxidant activity.

Sulfated modification and DPPH free radical scavenging ability of polysaccharide from Rhodiola sachalinensis / 中草药

Objective: To optimize the sulfated modification conditions of Rhodiola sachalinensis polysaccharide (RSP) and improve the anti-oxidant activity of RSP. Methods: RSP were sulfated by chlorosulfonic acid-pyridine method, and the optimal conditions for the sulfated modification were determined by single factor experiments. The physical and chemical properties of RSP and sulfated RSP (S-RSP) were analyzed by infrared spectroscopy (IR) and scanning electron microscopy (SEM). The relation between substituting degree (DS) of S-RSP and anti-oxidative activity of polysaccharide was investigated by testing the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging ability of RSP and S-RSP. Results: When the volume ratio of chlorosulfonic acid to pyridine was 1∶4, the reaction time was 2 h and the reaction temperature was 60 ℃, the maximum sulfur content of S-RSP was 18.83% and the DS was the highest for 2.38. Moreover, the anti-oxidant activity of RSP was enhanced by the sulfated modification, and there was a certain positive proportional relationship between DS and DPPH free radical scavenging ability of S-RSP. Conclusion: The volume ratio of chlorosulfonic acid to pyridine affects the DS of S-RSP, and the sulfated modification can increase the anti-oxidant capacity of RSP by changing its polarity.

Screening of Antioxidant Active Components of Schisandra chinensis / 中国药房

OBJECTIVE:To screen antioxidant active components of Schisandra chinensis. METHODS:The orthogonal test was adopted to optimize extraction technology using DPPH free radical scavenging activity(IC50)as index and ethanol volume frac-tion,material-liquid ratio and extraction time as factors,and the verification test were made. The fractions(SC-0,SC-10,SC-30, SC-50,SC-70,SC-95) were made by extracting and purifying S. chinensis with macroporous resin with water and 10%,30%, 50%,70%and 95%ethanol. With IC50 and total antioxidant capacity(determined by ABTS method)as indexes(vitamin C as pos-itive control),the antioxidant active components of S. chinensis were optimized. The contents of 5 kinds of lignan in different posi-tions of S. chinensis were determined by HPLC. RESULTS:The optimal extraction condition of S. chinensis was as follows as 60% ethanol,material-liquid ratio of 1∶14,extracting for 2.0 h. The average IC50 of DPPH free radical scavenging activity was 23.81 mg/ml(RSD=0.52%,n=3)in verification test. SC-0 did not have antioxidant abilities. DPPH free radical scavenging activi-ty of those components (ie. the IC50 value from low to high) were in the following order of positive control>SC-50>SC-30>SC-95>SC-70>SC-10;total antioxidant ability of them were in the following order of SC-50>positive control>SC-30>SC-70>SC-95>SC-10;the contents of 5 types of lignan in different components were in the following order of SC-70>SC-50>SC-95>SC-30. CONCLUSIONS:The antioxidant active component of S. chinensis is 50%ethanol eluate.

Evaluation of cytotoxic and antioxidant activity of different fractions of methanolic extract of Baccaurea ramiflora (Lour.) fruits.

Chloroform and petroleum ether soluble fractions of the crude methanolic extract of the fruits of Baccaurea ramiflora (Lour.) have been investigated for the evaluation of cytotoxic and antioxidant activity. Brine shrimp lethality bioassay was used to evaluate the cytotoxic activity and free radical scavenging activity method was used to evaluate antioxidant activity. In brine shrimp lethality bioassay, the chloroform soluble fraction showed greater cytotoxic activity (LC50 value 74.2 μg/ml) than petroleum ether soluble fraction (LC50 value 129 μg/ml) compared to the standard drug vincristine sulfate (LC50 value 0.54 μg/ml). In free radical scavenging activity method (DPPH assay method), the chloroform soluble fraction showed greater antioxidant activity (IC50 value 49.78 μg/ml) than petroleum ether soluble fraction (IC50 value 75.31 μg/ml) compared to the standard antioxidant butylated hydroxytoluene (IC50 value 24.51μg/ml). This study reveals that Baccaurea ramiflora fruit possesses cytotoxic and antioxidant activity hence can be a potential source for the isolation of active principle(s) for different therapies.

Evaluation of cytotoxic and antioxidant activity of different fractions of methanolic extract of Baccaurea ramiflora (Lour.) fruits.

Chloroform and petroleum ether soluble fractions of the crude methanolic extract of the fruits of Baccaurea ramiflora (Lour.) have been investigated for the evaluation of cytotoxic and antioxidant activity. Brine shrimp lethality bioassay was used to evaluate the cytotoxic activity and free radical scavenging activity method was used to evaluate antioxidant activity. In brine shrimp lethality bioassay, the chloroform soluble fraction showed greater cytotoxic activity (LC50 value 74.2 μg/ml) than petroleum ether soluble fraction (LC50 value 129 μg/ml) compared to the standard drug vincristine sulfate (LC50 value 0.54 μg/ml). In free radical scavenging activity method (DPPH assay method), the chloroform soluble fraction showed greater antioxidant activity (IC50 value 49.78 μg/ml) than petroleum ether soluble fraction (IC50 value 75.31 μg/ml) compared to the standard antioxidant butylated hydroxytoluene (IC50 value 24.51μg/ml). This study reveals that Baccaurea ramiflora fruit possesses cytotoxic and antioxidant activity hence can be a potential source for the isolation of active principle(s) for different therapies.

Study on Anti-oxidant Activity Parts of Ferula sinkiangensis K. M. Shen / 中国中医药信息杂志

Objective To establish a high-throughput detection of medicine on DPPH free radical scavenging activity;To analyze and preliminarily screen the anti-oxidant activity part of Ferula sinkiangensis. Methods Taking DPPH free radical scavenging rate of ascorbic acid as positive control, and IC50 as the evaluating criterion of DPPH free radical scavenging capability, oxidation resistance of different polar parts (petroleum ether part, ethyl acetate part, methyl alcohol part, and water part) of Ferula sinkiangensis was evaluated and screened. Results Different polarity parts of Ferula sinkiangensis DPPH radical scavenging of IC50 were:petroleum ether part 3252.22 μg/mL, ethyl acetate part 36.22 μg/mL, methyl alcohol part 32.22 μg/mL, water part 2643.38 μg/mL, and positive control group ascorbic acid 27.16 μg/mL. Conclusion The ethyl acetate and methyl alcohol parts of Ferula sinkiangensis were effective anti-oxidant activity site to eliminate DPPH free radicals. In this study, a simple, sensitive, and high-throughput detection method of DPPH radical scavenging assay was established to provide reference for the anti-oxidation medicine detection screening.

Anti-inflammatory and antioxidant activities of ethanolic extract of aerial parts of Vernonia patula (Dryand.) Merr

Objective:To investigate the inflammatory and antioxidant activities of ethanolic extract of aerial part of Vernonia patula (Dryand.) Merr (EAV). Methods:The anti-inflammatory activity of EAV was studied using carrageenan and histamine-induced rat paw edema test at different doses (100, 200 and 400 mg/kg body weight). DPPH free radical scavenging, nitric oxide scavenging, reducing power and Fe2+ion chelating ability were used for determining antioxidant activities. Results: The EAV, at the dose of 400 mg/kg, showed a significant anti-inflammatory activity (P Conclusions: Therefore, the obtained results suggest the acute anti-inflammatory and antioxidant activities of the EAV and thus provide the scientific basis for the traditional uses of this plant part as a remedy for inflammations.

Antioxidant capacity of extracts and isolated compounds from Stryphnodendron obovatum Benth / Capacidade antioxidante de extratos e compostos isolados de Stryphnodendron obovatum Benth

The extract from stem bark of Stryphnodendron obovatum Benth. was chromatographed on a Sephadex® LH-20 column, and yielded nine compounds: gallic acid (GA), p-hydroxybenzoic acid (PHB), gallocatechin (GC), epigallocatechin (EPG), 4'-O-methylgallocatechin (MGC), epigallocatechin-(4β→8)-epigallocatechin (EPEP), epigallocatechin-(4β→8)-gallocatechin (EPGC), robinetinidol-(4α→8)-gallocatechin (ROGC) and robinetinidol-(4β→8)-epigallocatechin (ROEP). Evaluation of the antioxidant capacity in vitro by the methods of DPPH free radical (IC50; μg/mL) and reduction of the phosphomolybdenum complex (RAC) gave the following results, respectively: crude extract 4.52 and 0.8242; ethyl-acetate fraction 4.04 and 0.9537; aqueous fraction 5.58 and 0.9275. The crude extract and ethyl-acetate fraction were shown to possess an antioxidant capacity comparable to that of vitamin C (4.93 and 1.0). The values obtained by the DPPH free-radical method for the isolated compounds were IC50 (μM): GA=8.89; PHB=10.12; GC=16.46; EPG=13.20; MGC=21.00; EPEP=6.89; EPGC=4.91; ROGC=7.78 and ROEP=6.20. Vitamin C and trolox showed 30.11 and 30.10, respectively. Dimers showed greater activity in scavenging free radicals, possibly related to the number of hydroxyls. However, compounds without a hydroxyl at position 5 of the A-ring (5-deoxy-proanthocyanidins) did not change the antioxidant activity of the DPPH free radical, as evaluated here for the first time. Among the monomers, there appeared to be a direct relationship in scavenging of free radicals because of the stereochemistry of the compounds. The presence of a methyl radical on the B-ring significantly reduced the scavenging of free radicals of gallocatechin. All compounds showed greater scavenging of radicals than vitamin C and trolox, and these two compounds showed no significant difference from each other.

O extrato das cascas de Stryphnodendron obovatum submetido à cromatografia em coluna, Sephadex® LH-20, forneceu nove substâncias: ácido gálico (GA), ácido p-hidróxibenzóico (PHB), galocatequina (GC), epigalocatequina (EPG), 4'-O-metilgalocatequina (MGC), epigalocatequina-(4β→8)-epigalocatequina (EPEP), epigalocatequina-(4β→8)-galocatequina (EPGC), robinetinidol-(4α→8)-galocatequina (ROGC) e robinetinidol-(4β→8)-epigalocatequina (ROEP). A capacidade antioxidante in vitro pelos métodos do radical livre DPPH (IC50; μg/mL) e do complexo fosfomolibdênio (CAR) apresentou os seguintes resultados, respectivamente: extrato bruto 4,52 e 0,8242; fração acetato de etila 4,04 e 0,9537 e fração aquosa 5,58 e 0,9275 demonstrando possuírem capacidade antioxidante quando comparados com vitamina C 4,93 e 1,0. Os valores obtidos pelo método do radical livre DPPH com as substâncias isoladas foram: IC50 (μM): GA=8,89; PHB=10,12; GC=16,46; EPG=13,20; MGC=21,00; EPEP=6,89; EPGC=4,91; ROGC=7,78 e ROEP=6,20. Vitamina C e trolox mostraram valores de 30,11 e 30,10, respectivamente. Os dímeros mostraram maior atividade no sequestro de radicais livres, possivelmente relacionada com o número de hidroxilas. No entanto, substâncias com ausência de hidroxila na posição 5 do anel A (5-desoxi-proantocianidinas) não alteraram o poder antioxidante frente ao radical livre DPPH, tendo sido avaliadas aqui pela primeira vez. Entre os monômeros, parece haver uma relação direta com a estereoquímica. A presença de um radical metila no anel B reduziu significativamente a atividade da galocatequina. Todas as substâncias isoladas mostraram maior atividade do que a vitamina C e trolox, e estes não mostraram diferença significativa entre si.

Capacidade antioxidante de frutas / Antioxidant capacity of the fruits

Extratos aquoso e acetônico de 15 frutas foram submetidos a ensaios para investigar a habilidade de seqüestrar o radical estável 1,1-difenil-2-picrilhidrazil (DPPH) e a capacidade de inibir a oxidação em sistema modelo β-caroteno/ácido linoléico. Todas as frutas exibiram propriedade antioxidante, entretanto a ação foi diferenciada entre elas. O extrato aquoso da acerola, caju, mamão "Formosa", mamão Havaí, laranja pêra e goiaba foram os mais eficazes (superior a 70 por cento), enquanto que o do abacaxi, laranja cravo, manga rosa, melão espanhol, melão japonês, melão orange flesh e pinha apresentaram ação moderada (60-70 por cento) e o da manga espada e melancia exibiram a mais fraca capacidade de seqüestrar o radical DPPH. Os extratos acetônico da acerola, caju, pinha e goiaba exibiram uma forte capacidade de seqüestrar o radical DPPH (superior a 70 por cento). Em sistema modelo β-caroteno/ácido linoléico, o extrato aquoso da pinha e o acetônico da goiaba exibiram moderada capacidade antioxidante (60-70 por cento) enquanto que a acerola (extrato aquoso) e o mamão formosa (extrato acetônico) os menores percentuais. Frente à capacidade antioxidante exibida, as frutas podem ser apontadas como fontes de antioxidantes naturais, destacando-se a acerola, caju, mamão Formosa, mamão Havaí, goiaba, laranja pêra, e a pinha por terem apresentado uma potente capacidade antioxidante.

Aqueous and acetone extracts from 15 fruits have been screened for antioxidant activity using DPPH method and ß-carotene/linoleic acid model. All fruits studied showed antioxidant activity, but in different extent. Acerola, cashew-apple, papaya "formosa", papaya "solo", orange and guava showed the higher antioxidant activity (>70 percent) in DPPH method, followed by pineapple, bergamont, mango "rosa", melon "reticulares", melon "inodorus", melon "orange flesh" and sugar-apple aqueous extract (moderate, 60-70 percent) and mango "espada" and watermelon aqueous extract, the lowest activity. Acerola, cashew-apple, sugar-apple and guava acetone extracts exhibited higher scavenging activity toward DPPH radicals (>70 percent).β-carotene/linoleic acid model index of sugar-apple aqueous extract and guava acetone extract demonstrated moderate antioxidant activity (60-70 percent), meanwhile acerola aqueous extract and papaya "formosa" acetone extract the lower. According to antioxidant activity, fruits can be indicated as natural antioxidants sources, pointing out acerola, cashew-apple, papaya "solo", papaya "formosa", guava, orange and sugar-apple as the highest in antioxidant capacity.