Antioxidant,antimicrobial, cytotoxic and analgesic activities of ethanolic extract of Mentha arvensis L.

ObjectiveTo investigate potential antioxidant, antimicrobial, cytotoxic and analgesic activities of ethanolic extract of Mentha arvensis L. in different in vivo and in vitro experimental models.MethodsIn vitro DPPH radical scavenging assay was used to evaluate the antioxidant activity of the plant extract. In vivo analgesic activity was carried out by acetic acid-induced writhing test in Swiss albino mice. All studies in mice were undertaken at the doses of 250 and 500 mg/kg body weight. Antibacterial activity was studied by disk diffusion assay against some Gram-positive and Gram-negative bacterial strains. Brine shrimp lethality assay was used to investigate cytotoxicity effects of the plant extract.ResultsThe extract showed free radical scavenging activity in the DPPH assay (IC₅₀∼41 μg/mL) compared to the standard antioxidant ascorbic acid (IC₅₀∼19 μg/mL). The extract also produced prominent antimicrobial activity against Salmonella typhi, Salmonella paratyphi, Shigella boydii, Streptococcus pyogenes and Streptococcus aureus compared to standard drug kanamycin at the dose of 30 μg/disc. The extract exhibited lethality against the brine shrimp nauplii with the LC₅₀ values of 40 μg/mL, and also 90% mortality (LC₉₀) value was found to be 160 μg/mL. In analgesic test, the extract demonstrated statistically significant (P<0.01) analgesic effect in acetic acid induced writhing in white albino mice at both dose levels.ConclusionsThese results suggest that the ethanolic extract of Mentha arvensis L. has potential antioxidant, antibacterial, cytotoxic and analgesic activities that support the ethnopharmacological uses of this plant.     

Antimicrobial activity against periodontopathogenic bacteria,antioxidant and cytotoxic effects of various extracts from endemic Thermopsis turcica

ObjectiveTo investigate the in vitro antimicrobial potential of Thermopsis turcica Kit Tan, Vural & Küçüködük against periodontopathogenic bacteria, its antioxidant activity and cytotoxic effect on various cancer cell lines.MethodsIn vitro antimicrobial activities of ethanol, methanol, ethyl acetate (EtAc), n-hexane and water extracts of Thermopsis turcica herb against periodontopathogenic bacteria, Aggregatibacter actinomycetemcomitans ATCC 29523 and Porphyromonas gingivalis ATCC 33277 were tested by agar well diffusion, minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). Antioxidant properties of the extracts were evaluated by 1,1-diphenyl-2-picryl-hydrazyl radical scavenging activity and β-carotene bleaching methods. Amounts of phenolic contents of the extracts were also analysed by using the Folin-Ciocalteu reagent. Additionally, cytotoxic activity of the extracts on androgen-insensitive prostate cancer, androgen-sensitive prostate cancer, chronic myelogenous leukemia and acute promyelocytic leukemia human cancer cell lines were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Human gingival fibroblast cells were used as a control.ResultsOur data showed that EtAc extract had the highest antimicrobial effect on Aggregatibacter actinomycetemcomitans (MIC: 1.562 mg/mL, MBC: 3.124 mg/mL) and Porphyromonas gingivalis (MIC: 0.781 mg/mL, MBC: 1.562 mg/mL). In antioxidant assays, EtAc extract exhibited also the highest radical scavenging activity [IC₅₀=(30.0±0.3) μg/mL] and the highest inhibition [(74.35±0.30)%] against lineloic acide oxidation. The amount of phenolic content of it was also the highest [(162.5±1.2) μg/mg gallic acid]. In cytotoxic assay, only ethanol [IC₅₀=(80.00±1.21) μg/mL] and EtAc extract [IC₅₀=(70.0±0.9) μg/mL] were toxic on acute promyelocytic leukemia cells at 20-100 μg/mL (P<0.05). However, no toxic effect was observed on human gingival fibroblast cells.ConclusionsAccording to our findings, owing to its antioxidant and cytotoxic potential, EtAc extract might include anticancer agents for acute promyelocytic leukemia.     

Inhibitory effect of polyphenolic–rich extract from Cola nitida (Kolanut) seed on key enzyme linked to type 2 diabetes and Fe2+ induced lipid peroxidation in rat pancreas in vitro

ObjectiveTo investigate the inhibitory effect of phenolic-rich extracts from Cola nitida (C. nitida) seeds on key enzymes linked with type-2 diabetes and Fe²⁺ induced oxidative stress in rat pancreas.MethodsThe phenolic extract was prepared with 80% acetone (v/v). Subsequently, the antioxidant properties and inhibitory effect of the extract on α – amylase and α – glucosidase as well as on Fe²⁺ induced lipid peroxidation in rat pancreas were determined in vitro.ResultsThe result revealed that C. nitida extract inhibited α-amylase (EC₅₀=0.34 mg/mL) and α-glucosidase (EC₅₀=0.32 mg/mL) activities as well as Fe²⁺ induced lipid peroxidation in rat pancreas in a dose dependent manner. In addition, the extract had high DPPH radical scavenging ability (EC₅₀=2.2 mg/mL) and reducing power (8.2 mg AAE/g). Characterization of the main phenolic compounds of the extract using gas chromatography analysis revealed catechin (6.6 mg/100 g), epicatechin (3.6 mg/100 g), apigenin (5.1 mg/100 g) and naringenin (3.6 mg/100 g) were the main compounds in the extract.ConclusionsThis antioxidant and enzyme inhibition could be some of the possible mechanism by which C. nitida is use in folklore for the management/treatment of type-2 diabetes. However, the enzyme inhibitory properties of the extract could be attributed to the presence of catechin, epicatechin, apigenin and naringenin.     

Antioxidant and anti–acetylcholinesterase activities of extracts and secondary metabolites from Acacia cyanophylla

ObjectiveTo investigate the antioxidant potential and anti-acetycholinesterase activity of compounds and extracts from Acacia cyanophylla (A. cyanophylla).MethodsThree polyphenolic compounds were isolated from ethyl acetate extract of A. cyanophylla flowers. They have been identified as isosalipurposide 1, quercetin 2 and naringenin 3. Their structures were elucidated by extensive spectroscopic methods including 1D and 2D NMR experiments as well as ES-MS. The prepared extracts and the isolated compounds 1–3 were tested for their antioxidant activity using 1′-1′-diphenylpicrylhydrazyl (DPPH) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) scavenging assays and reducing power. They have been also investigated for inhibitory effect against acetylcholinesterase using the microplate assay.ResultsIn the DPPH test, the EtOAc extract of flowers exhibited the highest antioxidant effect (67.26 μg/mL). Isosalipurposide 1 showed a significant antiradical power against DPPH (81.9 μg/mL). All extracts showed a dose-dependent acetylcholinesterase inhibition. In terms of the IC50 value, the butanolic extract (16.03 μg/mL) was the most potent sample. Isosalipurposide 1 was found to be active against AChE with an IC50 value of 52.04 μg/mL.ConclusionsThe results demonstrated the important antioxidant and anti-acetylcholinesterase activity of pure compounds and extracts from A. cyanophylla.     

Phytochemical investigation and in vitro antioxidant activity of an indigenous medicinal plant Alpinia nigra B.L. Burtt

Objective

To investigate antioxidant potential of methanol extract of Alpinia nigra leaves.

Methods

The study was done by using various in vitro methods such as 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), nitric oxide and hydrogen peroxide radical scavenging assays. Phytochemical constituents, total phenolic content and total flavonoid content of the extract at different concentrations (10-500 µg/mL) were determined.

Results

Alpinia nigra leaves showed high free radical scavenging activity as evidenced by the low IC₅₀ values in DPPH (64.51 µg/mL), in ABTS (28.32 µg/mL), in nitric oxide (80.02 µg/mL) and in H₂O₂ (77.45 µg/mL) scavenging assays. Furthermore the TPC and TFC of the extract were found to be 69.25 mg gallic acid equivalent per gram of extract and 78.84 mg quercetin equivalent per gram of extract respectively.

Conclusions

The results of present comprehensive analysis demonstrated that Alpinia nigra leaves possess high phenolic, flavonoid contents and potential antioxidant activity, and could be used as a viable source of natural antioxidants and might be exploited for functional foods and neutraceutical applications.     

Evaluation of phenolic contents and antioxidant activities of brown seaweeds belonging to Turbinaria spp. (Phaeophyta,Sargassaceae) collected from Gulf of Mannar

Objective

To evaluate the antioxidant activities and total phenolic contents of brown seaweeds belonging to Turbinaria spp. [Turbinaria conoides (T. conoides) and Turbinaria ornata (T. ornata) collected from Gulf of Mannar of southeastern coast of India in various in vitro systems.

Methods

The antioxidant activity was evaluated using different in vitro systems, viz., 1, 1-diphenyl-2-picrylhydrazyl (DPPH), 2, 2′-azino-bis-3 ethylbenzothiozoline-6-sulfonic acid diammonium salt (ABTS), H₂O₂/HO radical scavenging, Fe²⁺ ion chelating ability, and reducing potential. Folin-Ciocalteu method was used to determine the total phenolic content of the extracts, and the results were expressed as mg of gallic acid equivalents (GE)/g of the seaweed extracts. Thiobarbituric acid-reactive substances assay was employed to assess the ability of the seaweed extracts to inhibit lipid oxidation.

Results

Ethyl acetate (EtOAc) fraction of T. conoides registered significantly higher phenolic content (105.97 mg GE/g) than that of T. ornata (69.63 mg GE/g). Significantly higher antioxidant potential as determined by DPPH (64.14%) radical scavenging activity was registered in EtOAc fraction of T. ornata. A higher ABTS^•+ radical scavenging (IC₅₀ 3.16 µg/mL), Fe²⁺ chelating (IC₅₀ 0.46 mg/mL), H₂O₂ scavenging (IC₅₀ 4.25 mg/mL), lipid peroxidation inhibitory (TBARS, IC₅₀ 0.21 mg/mL), and reducing abilities (IC₅₀ 52.67 mg/mL) (P<0.05) were realized in EtOAc fraction of T. ornata than other fractions.

Conclusions

This study indicated the potential use of T. conoides and T. ornata as candidate species to be used as food supplements/functional foods to increase shelf-life of food items for human consumption, and nutraceuticals to deter deleterious free radical-induced life-threatening diseases.     

A comparative study of the antioxidant,antimicrobial, cytotoxic and thrombolytic potential of the fruits and leaves of Spondias dulcis

Objective

To investigate the antioxidant, antimicrobial, cytotoxic and thrombolytic property of the fruits and leaves of Spondias dulcis (S. dulcis).

Methods

Methanolic extracts of fruits and leaves of S. dulcis were partitioned with chloroform and dichloromethane. The antioxidant potential of the crude extract and partitioned fractions were evaluated in terms of total phenolic content, total flavonoid content, DPPH radical scavenging potential, reducing potential and total antioxidant capacity by specific standard procedures. The antimicrobial activity was evaluated using disc diffusion method. The cytotoxicity was evaluated by using brine shrimp lethality bioassay and compared with vincristine sulfate. The thrombolytic activity was compared with streptokinase.

Results

The methanolic fruit extract exhibited the highest phenolic content, flavonoid content and antioxidant capacity, among the other extracts, with the highest DPPH radical scavenging activity at a concentration of 10 µg/mL (IC₅₀: 1.91 µg/mL) and maximum reducing power at a concentration of 100 µg/mL (EC₅₀: 3.58 µg/mL). Though all extract showed moderate antimicrobial activity against the bacterial strains, weak or no activity against fungus. The range of LC₅₀ value of all extracts was 1.335-14.057 µg/mL which was far lower than the cut off index for cytotoxicity. All extracts exhibited statistically significant (P<0.001) thrombolytic activity.

Conclusions

Our study suggested that S. dulcis exhibits antimicrobial activities against a wide variety of strains while it possesses significant antioxidant, cytotoxic and thrombolytic activity.     

Hepatoprotective and antioxidant activity of a mangrove plant Lumnitzera racemosa

Objective

To identify the hepatoprotective and in vitro antioxidant activity of Lumnitzera racemosa (L. racemosa) leaf extract.

Methods

Animals in Group 1 served as vehicle control, Group 2 served as hepatotoxin (CCL₄ treated) group, Group 3 served as positive control (Silymarin) group, and Group 4, 5 and 6 served as (75, 150 and 300 mg/kg bw p.o.) L. racemosa leaf extract treated groups. Moreover, in vitro antioxidant DPPH, hydroxyl radical scavenging activity (HRSA), NO, ferric reducing antioxidant power (FRAP), lipid hydroperoxide (LPO) and super oxide dismutase (SOD) were also analyzed for the leaf extract.

Results

The levels of the serum parameters such as serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), alkaline phosphatase (ALP), bilirubin, cholesterol (CHL), sugar and lactate dehydrogenase (LDH) were significantly increased in CCL₄ treated rats when compared with the control group (P<0.05). But the L. racemosa leaf extract treated rats showed maximum reduction of SGOT [(210.36±19.63) IU/L], SGPT [(82.37±13.87) IU/L], ALP [(197.63±23.43) IU/L], bilurubin [(2.15±0.84) mg/dL], cholesterol [(163.83±15.63) mg/dL], sugar [(93.00±7.65) mg/dL] and LDH [(1134.00±285.00) IU/L] were observed with the high dose (300 mg/kg bw) of leaf extract treated rats. Histopathological scores showed that, no visible changes were observed with high dose (300 mg/kg bw) of leaf extract treated rats except few mild necrosis. The IC₅₀ values were observed as (56.37±4.87) µg/mL, (57.68±1.98) µg/mL, (64.15±2.90) µg/mL, (61.94±3.98) µg/mL, (94.53±1.68) µg/mL and (69.7±2.65) µg/mL for DPPH, HRSA, NO, FRAP, LPO and SOD radical scavenging activities, respectively.

Conclusions

In conclusion, the hepatoprotective effect of the L. racemosa leaf extract might be due to the presence of phenolic groups, terpenoids and alkaloids and in vitro antioxidant properties.     

Antiglycation,antioxidant and toxicological potential of polyphenol extracts of alligator pepper,ginger and nutmeg from Nigeria

Objective

To evaluate the antioxidant and antiglycation potential of polyphenols from three spices; alligator pepper, ginger and nutmeg.

Methods

Polyphenol extracts of these spices were subjected to brine-shrimp lethality assay, phytotoxicity test, DPPH and superoxide anion radical scavenging as well as BSA-glucose antiglycation assay.

Results

Results obtained showed that polyphenol extract of ginger has the highest antioxidant potential with IC₅₀ 0.075 and 0.070 mg/mL for DPPH and superoxide anion radical scavenging assay while alligator pepper displayed highest antiglycation activity with IC₅₀ 0.125 mg/mL. However, nutmeg extract exhibited weakest cytotoxic and phytotoxic potential with LD₅₀ 4359.70 and 1490 µg/mL respectively.

Conclusions

It can be concluded that the polyphenol extracts of alligator pepper, ginger and nutmeg displayed good antioxidant as well as antiglycation potential and are safe for consumption.     

Hepatoprotective and Antioxidant Activity of Rhizome of Podophyllum hexandrum against Carbon Tetra Chloride Induced Hepatotoxicity in Rats

Objective To test possible antioxidant activity of n-hexane extract of Podophyllum hexandrum under in vitro and in vivo conditions. Methods The in vitro antioxidant activity was evaluated by the ability of the extract to interact with the stable free radical DPPH, Superoxide (O2-), Hydroxyl (OH-), Hydrogen peroxide (H2O2) radicals, and reducing power ability of the extract was also evaluated. Under in vivo conditions the extract was evaluated for its hepatoprotective activity by measuring different biochemical parameters, such as serum alanine aminotransaminase, serum aspartate aminotransaminase and serum lactate dehydrogenase and antioxidant enzymes. Antioxidant status was estimated by determining the activities of antioxidative enzymes, glutathione reductase (GR), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and superoxide dismutase (SOD), and by determining the levels of reduced glutathione (GSH) and thiobarbituric acid reactive substances (TBARS). Results Hexane extract of P. hexandrum exhibited good radical scavenging capacity in neutralization of DPPH, O2-, OH -, and H2O2 radicals in a dose dependent manner. n-hexane extract of Podophyllum hexandrum at the doses of 20, 30, and 50 mg/kg-day produced hepatoprotective effect by decreasing the activity of serum marker enzymes, while it significantly increased the levels of glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), super oxide dismutase (SOD), and glutathione-S-transferase (GST) in a dose dependant manner. The effect of n-hexane extract was comparable to that of standard antioxidant vitamin E. Conclusion The extract of Podophyllum hexandrum possess free radical scavenging activity under in vitro conditions and could protect the liver tissue against CCl 4 induced oxidative stress probably by increasing antioxidant defense activities.     

Protective capacity of Artemisia annua as a potent antioxidant remedy against free radical damage

ObjectiveTo evaluate the antioxidant capacity of four leaf-derived solvent extracts of Artemisia annua (A. annua), a medicinal plant widely touted for its vast phyto-therapeutic potential.MethodsA. annua leaves were extracted with four solvents (absolute ethanol, absolute methanol, 70% ethanol and 70% methanol), and extracts obtained studied by five complementary in vitro antioxidant test systems using ascorbic acid (vitamin C) and rutin as standard references.ResultsThe extracts remarkably inhibited lipid peroxidation (79.81%-86.70%), and erythrocyte haemolysis (40.02%-49.91%). Their IC₅₀ values for hydroxyl, nitric oxide and hydrogen peroxide radical scavenging activities ranged from 2.39–3.81 mg/mL (superior to the standards), 107.24–144.49 μg/mL and 28.53–53.20 μg/mL, respectively. 70% alcohol extracts generally showed better antioxidant activity than absolute alcohol extracts.ConclusionsThe results indicate that A. annua leaf extracts have potent antioxidant activities that would have beneficial effect on human health, and aqueous organic solvents are superior to the absolute counterparts in yielding extracts with better antioxidant potential.     

Effect of an extraction solvent on the antioxidant quality of Pinus densiflora needle extract

Pinus densiflora needle extract (PDNE) is widely reported to have many pharmacological activities including antioxidant potential. However, the solvent system used for extraction greatly affects its antioxidant quality. Hence, in the present study, we investigated the effect of a different ratio (vol/vol) of ethanol to water (0–100%) in the extraction of PDNE with potent antioxidant capacity. The chemical assays, 2,2-diphenyl-1 picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), were conducted to assess the antioxidant potential of PDNE. Subsequently, the cytoprotective effect of PDNE was determined using tert-butyl hydroperoxide (TBHP)-challenged HepG2 cellular model. The needle extracts from 40% ethanol (PDNE-40) showed greater radical scavenging activity followed by 60%, 20%, 80%, 0% and 100% ethanol extracts. EC₅₀ value of the most active extract, PDNE-40, was 8.56 ± 0.51 μg/mL, relative to 1.34 ± 0.28 μg/mL of the standard trolox (for ABTS radical), and 75.96 ± 11.60 μg/mL, relative to 4.83 ± 0.26 μg/mL of the standard trolox (for DPPH radical). Either PDNE-20 or PDNE-40 pretreatment remarkably decreased the levels of reactive oxygen species (ROS), lipid peroxides and protein carbonyls in TBHP-challenged HepG2 cells. In addition, both PDNE-20 and PDNE-40 significantly reversed the decreased ratio of reduced (GSH) to oxidized (GSSG) glutathione. Moreover, these two extracts showed a significant inhibitory effect on TBHP-induced nuclear damage and loss of cell viability. In summary, the inclusion of 40% ethanol in water for extraction of Pinus densiflora needle greatly increases the antioxidant quality of the extract.     

Methanolic extract from Lespedeza bicolor: potential candidates for natural antioxidant and anticancer agent

Objective

To evaluate the anticancer, antioxidant and antimicrobial activities along with total phenolic and flavonoids contents extracted from Lespedeza bicolor indigenous to Khyber Pukhtoonkhwa, Pakistan.

巴戟天不同炮制品抗氧化作用比较研究

目的 比较巴戟天及其不同炮制品不同极性部位的抗氧化作用。方法 采用清除苯代苦味肼基（DPPH）自由基,清除[2,2''-连氨-（3-乙基苯并噻唑啉-6-磺酸）二氨盐]（ABTS）自由基及铁离子还原/抗氧化能力（FRAP）测定法,以Trolox、Vc等为阳性对照,对巴戟天生品、炮制品、不同的极性部位进行抗氧化活性评价。结果 巴戟天生品及炮制品均有一定的抗氧化活性,巴戟天及其不同炮制品的乙酸乙酯提取部位清除ABTS自由基能力和清除DPPH能力最强;总多糖部位清除ABTS自由基能力较强,巴戟天生品总多糖的IC₅₀值为0.197mg/ml;剩余水部位的还原铁离子能力最强。结论 不同炮制方法对巴戟天抗氧化活性具有不同程度的影响。     

Pedalium murex Linn (Pedaliaceae) fruits: a comparative antioxidant activity of its different fractions

Objective

To examine the antioxidant activity and total phenolic content of different solvent fractions of Pedalium murex (P. murex) Linn fruits (Family: Pedaliaceae) as well as the correlation between the total antioxidant capacity and total phenolic content.

Methods

In the present study, the antioxidant activities of P. murex were evaluated using six in-vitro assays, namely total antioxidant assay, DPPH assay, reducing power, nitric oxide scavenging, hydrogen peroxide scavenging and deoxyribose scavenging assays, and total phenol contents were also investigated.

Results

The ethyl acetate (EA) fraction was found to have high levels of phenolic content (298.72±2.09 mg GAE/g). The EA fraction exhibit higher total antioxidant capacity, higher percentage of DPPH radical scavenging activity (135.11±2.95µg/mL), nitric oxide (200.57±4.51µg/mL), hydrogen peroxide (217.91±6.12 µg/mL), deoxyribose (250.01±4.68µg/mL) and higher reducing power. Correlation coefficient (r²=0.914) was found to be significant between total phenolic content and total antioxidant activity.

Conclusions

In general, the results indicate that the EA fractions are rich in phenolic antioxidants with potent free radical scavenging activity implying their importance to human health.     

Inhibition of Platelet Aggregation and In Vitro Free Radical Scavenging Activity of Dried Fruiting Bodies of Pleurotus eous

Objective: To evaluate the ethyl acetate, methanol and aqueous extracts of dried fruiting bodies of Pleurotus eous for its anti-platelet activity on human volunteer''s blood. And also to analyze the free radical scavenging property of the extracts of P.eous by using various in vitro models. Methods: Anti-platelet activity of dried fruiting bodies of P.eous was evaluated by in vitro model using blood platelets. Inhibition of platelet aggregation was monitored after pre-incubation of platelets with the crude extracts of mushroom P.eous. Antioxidant activities of extracts of P.eous were evaluated by different in vitro experiments, namely, 1, 1-diphenyl- 2-picryl hydrazyl (DPPH), superoxide, hydroxyl radical and lipid peroxide radical models. Results: Crude extracts of mushroom P.eous inhibited platelet aggregation dose-dependently which was induced by adenosine diphosphate (ADP). At a maximum concentration of 10 mg/mL, methanol extract effected 64.02% inhibition of lipid per-oxidation and 50.12% scavenging effect on superoxide anion radical. Aqueous extract of P.eous have shown 69.43% chelating ability on ferrous ions, 24.27% scavenging effect on hydroxyl radical and 49.57% scavenging effect on DPPH radical at 10 mg/mL. Increasing concentrations of the extract were found to cause progressively decreasing of the intensity of absorbance. Conclusions: Anti-platelet effects could be related in part to the polyphenolic compounds present in the extracts. Antioxidant activity results indicated the free radical scavenging property of the extracts of P.eous which might be due to the high content of phenolic compounds and flavonoids.     

DPPH法评价伸筋草不同提取物清除自由基的能力

目的 研究伸筋草石油醚、氯仿及正丁醇提取物在DPPH法体外模型中的抗氧化作用及作用时间与清除率的关系。方法 建立DPPH体系,采用HPLC法测定反应体系中DPPH变化,观察伸筋草各提取物不同时间对DPPH自由基的清除率。结果 伸筋草各提取物对DPPH的清除均有抑制作用,且呈明显剂量–效应关系,其清除率随作用时间增长而增加。石油醚、氯仿及正丁醇提取物对DPPH的IC₅₀分别为0.56、0.31、0.13 g/mL;结论 伸筋草正丁醇提取物具有较强的清除自由基活性。     

In-vitro antioxidant and anti-inflammatory activities of ethanol stem-bark extract of Blighia sapida K.D. Koenig

Blighia sapida (B. sapida) K.D. Koenig (Family Sapindaceae) is a branchless straight bole approximately 15 m in length. The study evaluated the antioxidant and anti-inflammatory activities of ethanol extract and fractions of B. sapida stem-bark using in vitro methods. Ethanol extract and its fractions were investigated for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP), total antioxidant capacity (TAC), and quantitative phenolic and flavonoid contents. Anti-inflammatory activity was evaluated using albumin denaturation and membrane stabilization assays. The extract and its fractions exhibited radical scavenging and anti-inflammatory properties. The ethyl acetate fraction possessed maximum phenolic and flavonoid contents (136.67 ± 1.55 gallic acid equivalent mg/g and 75.76 ± 4.03 quercetin equivalent mg/g, respectively). Antioxidant studies revealed that the ethyl acetate fraction displayed superior activity with an IC₅₀ = 0.09 ± 0.03 mg/mL DPPH, and values of 146.96 ± 3.81 ascorbic acid equivalent (AAE) mg/g and 359.20 ± 4.98 AAE mg/g for FRAP and TAC, respectively. Furthermore, the anti-inflammatory activity was revealed by inhibition of heat-induced albumin denaturation and red blood cell membrane stabilization at concentrations of 200–1000 μg/mL and 50–250 μg/mL, respectively. The ethanol extract and fractions exhibited antioxidant and anti-inflammatory activities, with ethyl acetate fraction showing superior activity, which could be attributed to secondary metabolites, mainly phenolic compounds. Overall, the antioxidant and anti-inflammatory activities of B. sapida can be exploited by ethnomedicinal users.     

红参多糖抗氧化活性的研究

[目的]评价红参多糖的体外抗氧化能力。[方法]以热水回流提取法（料水比1：10,100℃下提取4h）从红参（RGR）根茎提取的多糖为材料,通过1,1-二苯基-2-苦肼基自由基（DPPH）自由基清除率、清除羟自由基活性和还原能力测定等体外抗氧化实验来评价红参多糖的体外抗氧化能力。[结果]红参多糖清除、羟基自由基能力和还原能力均随多糖浓度的增加而上升;1mg.mL-1的多糖对DPPH自由基的清除率高达67.61%,对羟基自由基的清除率为36.43%,在还原力的测定中,1 mg.mL-1多糖在700 nm下吸光值为0.447。[结论]红参多糖有较强的抗氧化能力,对体外自由基有较好的清除作用。     

新疆葡萄树伤流液蛋白含量测定及抗氧化活性研究

目的了解新疆葡萄树伤流液蛋白含量及其抗氧化能力。方法采用考马斯亮蓝法测定新疆葡萄树伤流液的蛋白含量;以抗坏血酸为阳性对照,应用ABTS法、羟A由基试剂盒法、DPPH法和亚硝酸盐法,研究其对自由基的清除能力。结果不同产地、品种的葡萄树伤流液蛋白含量不同,其中和田木纳格最高,为22．4±0．07μg／mL;不同产地、品种的葡萄树伤流液清除自由基的能力不同,但对·OH的清除能力明显高于对DPPH·和NO2^-·的清除能力。结论新疆葡萄树伤流液因产地和品种的不同,其蛋白含量及清除自由基能力也不同。