In vitro antiproliferative and antioxidant activities and total phenolic contents of the extracts of Melastoma malabathricum leaves

The present study aims to determine the in vitro antiproliferative and antioxidant activities of various extracts from the leaves of Melastoma malabathricum using various established in vitro assays. The aqueous extract inhibited the proliferation of Caov-3 and HL-60 cell lines, while the chloroform extract exhibited antiproliferative activity against the Caov-3, HL-60, and CEM-SS cell lines. The methanol extract demonstrated antiproliferative activity against more cell lines, including the MCF-7, HeLa, Caov-3, HL-60, CEM-SS, and MDA-MB-231 cancer cell lines. Interestingly, all extracts did not inhibit the proliferation of 3T3 cells, thus indicating their noncytotoxic properties. Unlike the chloroform extracts, the aqueous and methanol extracts of M malabathricum (20, 100, and 500 μg/ml) produced high antioxidant activity for the superoxide scavenging assay with only the 500 μg/ml aqueous and methanol extracts exhibited high activity for the 2,2-diphenyl -1-picrylhydrazyl radical scavenging assay. The total phenolic content recorded for the aqueous, methanol, and chloroform extracts were 3344.2 ± 19.1, 3055.1 ± 8.7, and 92.5 ± 7.3 mg/100 g of gallic acid, respectively. The M malabathricum leaves possessed potential antiproliferative and antioxidant activities that could be attributed to its high content of phenolic compounds.     

In vitro antioxidant and antiproliferative activity of the stem extracts from Graptopetalum paraguayense

This study was aimed to evaluate the antioxidant abilities of water (SGWE), 50% ethanolic (SGE50) and 95% ethanolic (SGE95) extracts from the stem of Graptopetalum paraguayense, and the extract with the highest antioxidant activity was assayed for its inhibitory effect on proliferation of human hepatoma (Hep G2) cell line. Antioxidant abilities of extracts were assessed their radical-scavenging abilities and effects on Fe/ascorbate-induced lipid peroxidation in a liposome model system. The results of this study showed that antioxidant activities were increased with the increase of the extracts concentrations, and the activities correlated with both the total phenol and anthocyanin contents. A comparison of the 50% inhibition concentration (IC(50)) values of different antioxidant reactions revealed that SGWE was the more effective at scavenging superoxide anion radical and preventing lipid peroxidation than SGE50 and SGE95 (p<0.05). The flow cytometry results indicated that SGWE lowered cell viability, and induced G1 phase arrest and apoptosis in Hep G2 cells. These results demonstrated the antioxidant and anti-hepatoma potential of stem of Graptopetalum paraguayense.     

In vivo topical anti-inflammatory and in vitro antioxidant activities of two extracts of Thymus satureioides leaves

Four extracts at increasing polarity were prepared from the leaves of Thymus satureioides Coss. (Labiatae) and assayed for the in vivo topical anti-inflammatory effect using the croton oil ear test in mice, and for in vitro both antioxidant (DPPH degrees test) and anti-bacterial (broth microdilution method) activities. The chloroform extract showed a topical anti-inflammatory activity (ID50=282 microg cm(-2)), only three times lower than that of the reference drug indomethacin (ID50=93 microg cm(-2)) and its active components were identified as ursolic and oleanolic acids. The methanol extract, showing a significant radical-scavenging effect (SC50=14.54 microg), was characterized by the isolation and identification of some flavonoids. On the contrary, the extracts did not show any anti-bacterial effect against four standard aerobial bacteria strains.     

In vitro assessment of antioxidant,neuroprotective, anti-urease and anti-tyrosinase capacities of Tamarix africana leaves extracts

OBJECTIVE: To characterize the chemical profile of methanolic crude extract and its fractions(Ethyl acetate, n-butanol and aqueous) using liquid chromatographymass spectrometry(LC-MS) analysis, to evaluate their biological and pharmacological properties: antioxidant(1, 1-diphenyl-2-pycrylhydrazyl(DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic)(ABTS·+), galvinoxyle free radical scavenging, reducing power, phenanthroline and β carotene-linoleic acid bleaching assays), enzymes inhibitory ...     

In vitro antioxidant and antimicrobial activity of extracts from Morus alba L. leaves, stems and fruits

In this study, the aqueous and ethanolic extracts (leaves, stems and fruits) from Morus alba L., a traditional Chinese medicine, were evaluated for their antioxidant and antimicrobial properties. Ethanolic extracts showed higher contents of both total phenolics and flavonoids than aqueous extracts. The total phenolic content was in the order of: leaf extracts > fruit extracts > stem extracts, whereas the total flavonoids was: leaf extracts > stem extracts > fruit extracts. Using DPPH assays, the concentrations providing 50% inhibition (IC(50)) values of aqueous extracts from leaves, stems and fruits were 7.11 ± 1.45 mg/ml, 86.78 ± 3.21 mg/ml and 14.38 ± 2.83 mg/ml, respectively, whereas the IC(50) values of ethanolic extracts were 3.11 ± 0.86 mg/ml, 14.62 ± 2.45 mg/ml and 12.42 ± 2.76 mg/ml, respectively. In sum, the antioxidant activities of ethanolic extracts from M. alba L. were stronger than the aqueous extracts, and in the order of: leaf extracts > fruit extracts > stem extracts. The ethanolic extracts exhibited moderate antimicrobial activities, whereas the aqueous extracts showed poor antimicrobial properties in our test system. This study validated the medicinal potential of M. alba L.     

苍耳七提取物的体外抗氧化活性研究(英文)

目的:了解苍耳七不同提取物中总黄酮含量、抗氧化活性及黄酮含量与抗氧化活性之间的相关性。方法:用三种不同有机溶剂依次对苍耳七 50 %乙醇提取物进行萃取,分别得到氯仿提取物(CE)、乙酸乙酯提取物(EAE)、正丁醇提取物(BE)和水相提取物(WE)。总黄酮含量采用 NaNO2- Al (NO3)3-NaOH 显色法测定。抗氧化活性采用羟基自由基清除试验、超氧自由基清除试验、DPPH 自由基清除试验、还原力测定和金属离子螯合试验进行综合评价,以 BHT(2, 6-二叔丁基对甲酚)为参考物质。结果:EAE 的黄酮含量最高,其次分别为 BE, WE 和 CE。WE 和 BE 的抗氧化活性强于 CE 和 EAE. 每种提取物的抗氧化活性都显示出浓度依赖性和黄酮含量的相关性。结论:苍耳七提取物可以被用作天然抗氧剂。     

In vitro antioxidant and in vivo anti-inflammatory activities of Ophioglossum thermale

Antioxidant fractions from Ophioglossum thermale were extracted with five different polar solvents using a Soxhlet type extractor. The total phenolic content of the extracts was determined by the Folin-Ciocalteu method. The ethyl acetate fraction of O. thermale was found to contain maximum phenolics. The dried fractions were screened for their antioxidant activity potential using in vitro model systems such as 1,1-diphenyl-2-picryl hydrazyl (DPPH), nitroblue tetrazolium (NBT) and lipid-peroxidation reduction at different concentrations. Results revealed that the EtOAc fraction exhibited the best performance in the DPPH assay, NBT assay and lipid peroxidation. All fractions showed more potent antioxidant capacity than green tea extract, a well-known antioxidant. Furthermore, the EtOAc fraction has the highest total phenolic content (475.65 mg of EGCG/g). In addition, the EtOAc fraction at 0.005% and 0.01% (g/100 ml) also significantly inhibited UVB irradiation-induced ROS generation in human dermal fibroblasts (HDFs). In a carrageenan-induced edema model, the EtOAc fraction showed an inhibitory effect (21.5%, p < 0.05) at 200 mg/kg (p.o.) after 300 min administration. Consequently, 3-O-methylquercetin (3MQ) was also isolated from the antioxidative EtOAc fraction. The data obtained using the above in vitro and in vivo tests suggest that the antioxidant activity of O. thermale and its anti-inflammatory effect on carrageenan-induced acute inflammation can be attributed to its ameliorating effect on oxidative damage, and thus it has great potential as a source for natural health products. To the best of our knowledge, this is the first report on the antioxidant activity of different polar extracts from O. thermale.     

In vivo anti-inflammatory and in vitro antioxidant activities of Mediterranean dietary plants

Five hydroalcoholic extracts of edible plants from Calabria region (Italy) used in local traditional medicine for the treatment of inflammatory diseases were evaluated for their in vivo topical anti-inflammatory activity (inhibition of croton oil-induced ear oedema in mice) and in vitro antioxidant and antiradical properties (inhibition of linoleic acid oxidation and bovine brain liposomes peroxidation, DPPH radical scavenging). All the extracts showed an anti-inflammatory effect: 300 microg/cm(2) provoked oedema reductions ranging from 21 to 27%. All the extracts exerted also radical scavenging and/or antioxidant properties, the most active plant being Mentha aquatica L. (Lamiaceae) which contained the highest amount of phenolics (337 mg/g) and of flavonoids (15.75 mg/g). Moreover, the content and the composition of sterols were assessed by GC-MS in the examined plants Borago officinalis L. (Boraginaceae) contained the highest number of sterols.     

In vivo and in vitro immunomodulatory activities of Trichilia glabra aqueous leaf extracts

The effects of Trichilia glabra (Meliaceae) aqueous leaf extract on mouse lymphocytes were studied. The in vitro proliferation of T and B lymphocytes was completely impaired. Besides, the extract significantly diminished both antibody and delayed hypersensitivity responses in treated mice. These results suggest that the extract exerts a marked immunomodulatory effect on the murine immune system.     

In vitro antioxidant activity of Anthriscus cerefolium L. (Hoffm.) extracts

Standardised aqueous extracts of chervil (Anthriscus cerefolium L. Hoffm.) (Apiacae) were investigated for antioxidant effect. Numerous in vitro test methods were used to determine whether the extracts, from different vegetative parts (root, herb) had H-donor, metal binding, reductive, free radical scavenging and membrane protective activity. Apiin was used as a reference material. The herb extract showed better activity in all experiments than the root extract. The present results underline that the wateric chervil extracts have antioxidant and anti-lipoperoxidant activity.     

Screening of Zingiberaceae extracts for antimicrobial and antioxidant activities

Dichloromethane and methanol extracts of 13 Zingiberaceae species from the Alpinia, Costus and Zingiber genera were screened for antimicrobial and antioxidant activities. The antimicrobial activity of most of the extracts was antibacterial with only the methanol extract of Costus discolor showing very potent antifungal activity against only Aspergillus ochraceous (MID, 15.6 microg per disc). All the extracts showed strong antioxidant activity comparable with or higher that of alpha-tocopherol.     

荔枝核与龙眼核水提取物的体外抗氧化活性的比较与评估

目的:分析比较荔枝核与龙眼核水提物体外抗氧化能力.方法:测定两种水提取物的主要化学成分,则定并比较二者的总抗氧化能力,清除羟自由基、超氧阴离子自由基以及DPPH能力.结果:龙眼核与荔枝核水提取物中多酚含量前者高于后者,总黄酮含量后者高于前者,二者均表现出较强的抗氧化能力.在一定浓度范围内龙眼核水提取物清除羟自由基、DPPH能力均高于荔枝核水提取物.荔枝核水提取物对超氧阴离子自由基有清除作用,而龙眼核水提取物在低浓度范围(0～1mg/mL)对超氧阴离子自由基有激发作用 结论:龙眼核水提取物在一定低浓度范围内的抗氧化活性优于荔枝核水提取物荔枝核与龙眼核水提取物抗氧化机制有所不同.     

香茅叶挥发油的化学成分及其体外抗氧化活性

目的研究香茅Cymbopogen citratus(DC.)Stapf叶挥发油的化学成分及其体外抗氧化活性。方法水蒸气蒸馏法提取香茅叶挥发油,气相色谱-质谱(GC-MS)法分析其化学成分,Folin-Ciocalteau比色法测定总多酚含有量。通过铁还原抗氧化能力(FRAP)和1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除法研究其体外抗氧化活性。结果最佳提取时间为5 h,提取率为1.30%。挥发油中共鉴定出17种成分,以开链单萜类化合物为主,醇类占76.98%,总多酚含有量为70.72 mg/g(没食子酸当量)。而且,挥发油对DPPH自由基的清除活性明显优于其5种主要单体成分(香茅醇、香叶醇、香茅醛、芳樟醇和乙酸香叶酯)。结论香茅叶挥发油主要由开链单萜类化合物组成,并且具有较好的体外抗氧化活性。     

In vitro and in vivo antihypertensive and antioxidant activities of fermented roots of Allium hookeri

Objective: To evaluate antihypertensive and antioxidant activities of Allium hookeri root (AHR) fermented with Lactobacillus plantarum, Leuconostoc mesenteroides, and Weissella cibaria. Methods: The novel fermented AHR products using L. plantarum, L. mesenteroides, and W. cibaria were developed and ACE inhibitory activity, DPPH radical scavenging activity, hydroxyl radical scavenging activity, superoxide anion radical scavenging activity, total phenolic content, and total thiosulfinate content were determined. The antihypertensive and antioxidant effects of fermented AHR were further investigated in spontaneously hypertensive rats (SHRs). Results: Administration of fermented AHR to SHRs had an attenuating effect on both diastolic and systolic blood pressure. The SHRs treated with fermented AHR showed lower plasma ACE activity and higher plasma NO levels. Furthermore, fermented AHR administration led to parallel improvements in plasma oxidative stress biomarkers in SHRs. Conclusion: Our results highlight the potential usefulness of fermented AHR for the prevention of hypertension.     

In vitro antioxidant evaluation and total phenolics of methanolic leaf extracts of Nyctanthes arbor-tristis L.

AIM： To investigate the in vitro antioxidant activity and total phenolic content of the methanolic leaf extract of Nyctanthes arbor-tristis L. （NA）. METHODS： The sample was tested using five in vitro antioxidant methods （1, 1-diphenyl-2-picryl hydrazine radical scavenging activity （DPPH）, hydroxyl radical-scavenging activity （-OH）, nitric oxide scavenging activity （NO）, superoxide radical-scavenging activity, and total antioxidant activity） to evaluate the in vitro antioxidant potential of NA and the total phenolic content （Folin-Ciocalteu method）. The extract showed good free radical scavenging property which was calculated as an IC50 value. RESULTS： IC50 （Half maximal inhibitory concentration） of the methanolic extract was found to be 57.93 μg.mL-1 for DPPH, 98.61 μg.mL-1 for-OH, 91.74 μg.mL-1 for NO, and 196.07 μg.mL-1 for superoxide radical scavenging activity. Total antioxidant ca- pacity of the extract was found to be （1198± 24.05） mg ascorbic acid for the methanolic extract. Free radical scavenging activity ob- served in the extracts of NA showed a concentration-dependent reaction. The in vitro scavenging tested for free radicals was reported to be due to high phenolic content in the leaf extract. The leaf extract of NA showed the highest total phenolic content with a value of 78.48 ± 4.2 equivalent nag TAE/g （tannic acid equivalent）. CONCLUSIONS： N. arbor-tristis leaf extract exhibited potent free radical scavenging activity. The finding suggests that N. arbor-tristis leaves could be a potential source of natural antioxidant.     

In vitro antimicrobial and antioxidant activities of anthrone and chromone from the latex of Aloe harlana Reynolds

In the search for new antimicrobial and antioxidant compounds from plants, the latex of the medicinal plant Aloe harlana Reynolds from Ethiopia was subjected to bioassay‐guided fractionation, which led to the isolation of two known compounds, anthrone (aloin) and chromone (7‐O‐methylaloeresin A). The latex and its two constituents were assessed for their possible antimicrobial activities against 23 bacterial and four fungal strains using the disc diffusion method and their antioxidant activity by two complementary test systems, namely 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and 2‐deoxyribose degradation assay methods. The isolated compounds showed promising results against various pathogenic bacterial and fungal strains in comparison with standard drugs. Moreover, 7‐O‐methylaloeresin A exhibited good activity against multiple drug resistant Staphylococcus aureus (NCTC 11994) and Salmonella typhimurium (ATCC 1255) with MIC values of 0.72 and 0.18 mm , respectively. Among the fungal strains tested, Candida albicans (ATCC 10231) was the most susceptible organism to the latex and the two isolated compounds. The latex and isolated compounds also showed significant activities on both antioxidant assays with the highest activity being observed for 7‐O‐methylaloeresin A, which gave IC₅₀ values of 0.026 mm and 0.021 mm for DPPH and 2‐deoxyribose degradation assay, respectively. These findings support the traditional uses of the plant for the treatment of various infectious and inflammatory diseases. Copyright © 2011 John Wiley & Sons, Ltd.     

In vitro anti-mycobacterial activities of three species of Cola plant extracts (Sterculiaceae)

Extracts obtained from three Nigerian Sterculiaceae plants: Cola accuminata, C. nitida and C. milleni were screened for anti-mycobacterium properties using a slow growing Mycobacterium bovis ATCC 35738 (designated BCG Mexican and known to have some virulence in mouse and guinea pig) at 1000 microg/ml using the radiometric (BACTEC) method. The extracts were also tested against six fast growing ATCC strains of M. vaccae using the broth microdilution method.The methanol extracts from both leaves, stem bark and root bark of Cola accuminata and from the leaves and stem bark of C. nitida and C. milleni were not active at the highest concentration of 1000 microg/ml. Only the methanol extract of root bark for both C. nitida and C. milleni were found to be potent against both M. bovis and strains of M. vaccae. The minimum inhibitory concentration (MIC) of C. nitida against M. bovis is 125 microg/ml while the MIC of C. milleni against M. bovis is 62.5 microg/ml after at least 6 days of inhibition with growth index (GI) units lesser than or equal to the change in GI units inoculated with a 1/100 of the BACTEC inoculum for a control vial.The minimum inhibitory concentration of C. milleni against the six ATCC strain of M. vaccae ranged from 62.5 microg/ml to 250 microg/ml while for C. nitida ranged from 500 microg/ml to above 1000microg/ml. Evidently, C. milleni has the highest inhibitory activity against both M. bovis and strains of M. vaccae used. Rifampicin, the positive control used has strong activity against M. bovis at the tested concentration of 5 microg and 10 microg/ml and 4 to 8 microg/ml against the six strains of M. vaccae.     

直杆桉果实提取物体外抗单纯疱疹病毒和乙型肝炎病毒的实验研究

目的:研究3种不同溶剂的直杆桉果实提取物体外抗单纯疱疹病毒Ⅰ型(HSV-1)和乙型肝炎病毒(HBV)的活性。方法:采用MTT法检测药物毒性,CPE法与空斑减数实验检测药物抗HSV-1活性;采用ELISA法检测药物对HepG2.2.15细胞分泌的乙型肝炎表面抗原(HBsAg)和乙型肝炎E抗原(HBeAg)的抑制作用。结果:直杆桉叶果实的醋酸乙酯提取物(P18-E1)和甲醇提取物(P18-E2)无明显抗HSV-1的活性,水提物(P18-E3)能明显抑制HSV-1的致病变作用,其TC50为69.20 mg/mLI,C50为126.77μg/mL,治疗指数为545.87;3种不同溶剂的提取物对HepG2.2.15细胞分泌的HBsAg和HBeAg均无明显抑制作用。结论:直杆桉果实的水提物(P18-E3)具有显著的抗HSV-1活性,主要是对病毒有直接灭活作用,也能影响病毒对细胞的吸附。初步推测其抗HSV-1活性的机理是影响病毒的囊膜结构从而使之失活。     

Activation of nitric oxide signaling pathway mediates hypotensive effect of Muntingia calabura L. (Tiliaceae) leaf extract

The cardiovascular effect of the crude methanol extract from the leaf of Muntingia calabura L. (Tiliaceae) was investigated in the anesthetized rats. The crude methanol extract was sequentially fractionated to obtain the water-soluble extract (WSE). Intravenous administration of the WSE (10, 25, 50, 75 or 100 mg/kg) produced an initial followed by a delayed decrease in systemic arterial pressure (SAP) in a dose-dependent manner. The M. calabura-induced initial hypotension lasted for 10 min and the delayed depressor effect commenced after 90 min and lasted for at least 180 min post-injection. The same treatment, on the other hand, had no appreciable effect on heart rate (HR) or the blood gas/electrolytes concentrations. Both the initial and delayed hypotensive effects of WSE (50 mg/kg, i.v.) were significantly blocked by pre-treatment with a nonselective nitric oxide (NO) synthase (NOS) inhibitor, N(G)-nitro-L-arginine methyl ester ((L)-NAME, 0.325 mg/kg/min for 5 min) or a soluble guanylate cyclase (sGC) inhibitor, 1H-[1,2,4]oxadiazole[4,3-alpha]quinoxalin-1-one (ODQ, 0.2 mg/kg/min for 5 min). Moreover, whereas the initial depressor effect of WSE was inhibited by pre-treatment with a selective endothelial NOS (eNOS) inhibitor, N5-(1-Iminoethyl)-L-ornithine ((L)-NIO, 1 mg/kg/min for 5 min), the delayed hypotension was attenuated by a selective inducible NOS (iNOS) inhibitor, S-methylisothiourea (SMT, 0.5 mg/kg/min for 5 min). Administration of WSE also produced an elevation in plasma nitrate/nitrite concentration, as well as an increase in the expression of iNOS protein in the heart and thoracic aorta. These results indicate that WSE from the leaf of M. calabura elicited both a transient and delayed hypotensive effect via the production of NO. Furthermore, activation of NO/sGC/cGMP signaling pathway may mediate the M. calabura-induced hypotension.     

Analysis of the phytochemical contents and antioxidant activities of crude extracts from Tulbaghia species

OBJECTIVE: To assess the phytochemical contents and antioxidant activities of crude extracts from selected Tulbaghia species.METHODS: Standard methods were used for preliminary phytochemical analysis. The total phenolic acid contents of the plant extracts were determined using the Folin-Ciocalteu method, and the total flavonoid contents were determined using the aluminum chloride colorimetric method. 1,1-Diphenyl-2-picrylhydrazyl and 2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) assays were used to evaluate the antioxidant activities.RESULTS: Phytochemical screening showed flavonoids, glycosides, tannins, terpenoids, saponins,and steroids were present in the Tulbaghia species.The total phenolic acid and flavonoid contents varied in the different plant extracts, ranging from4.50 to 11.10 mg of gallic acid equivalents per gram of fresh material and 3.04 to 9.65 mg of quercetin equivalents per gram, respectively. The IC50 values determined for Tulbaghia alliacea and Tulbaghia violacea based on 1,1-diphenyl-2-picrylhydrazyl(0.06 and 0.08 mg/m L, respectively) and 2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)(0.06 and 0.03 mg/m L, respectively) were low and showed they had potential antioxidant activities.CONCLUSION: Our results suggest that individual compounds from Tulbaghia species should be isolated for analysis of their antioxidant activity because some compounds may work best when pure.