Gas chromatography-mass spectrometry analysis of different organic crude extracts from the local medicinal plant of Thymus vulgaris L

Objective

To isolate and analyze the chemical composition in different crude extracts of from the leaves of locally grown of Thymus vulgaris L (T. vulgaris) by gas chromatography-mass spectrometry (GC-MS).

Methods

The shade dried leaves powder was extracted with methanol by using Soxhlet extractor. Methanol crude extracts of T. vulgaris and the derived fractions of hexane, chloroform, ethyl acetate and butanol were obtained.

Results

Qualitative analyses of various organic crude extracts of T. vulgaris by using GC-MS showed that there were different types of high and low molecular weight compounds. Most of the isolated and identified compounds by GC-MS in the crude extracts are basically biologically important. Further, the T. vulgaris leaf possessed certain characteristics that can be ascribed to cultivation on a domestic plantation. The crude extracts were prepared from the powder leaves of T. vulgaris for respective compounds can be chosen on the basis of above GC-MS analysis.

Conclusions

All the major compounds were identified and characterized by spectroscopic method in different organic crude extracts of T. vulgaris are biologically active molecules. Thus the identification of a good number of compounds in various crude extracts of T. vulgaris might have some ecological role.     

GC-MS analysis,determination of total phenolics,flavonoid content and free radical scavenging activities of various crude extracts of Moringa peregrina (Forssk.) Fiori leaves

ObjectiveTo perform phytochemical screening, estimate total phenolics, flavonoids and to evaluate antioxidant potential of Moringa peregrina (M. peregrina) leaves.MethodsThe dried powdered leaves of M. peregrina (150 g) were extracted exhaustively by Soxhlet with ethanol and then fractionated into hexane, chloroform, ethy alacetate and methanol. All the prepared extracts were also analyzed by gas chromatography-mass spectrometry to identify and characterize the chemical compounds present in the crude extracts. Folin- Ciocalteu reagent and aluminium chloride colorimetric methods were used to estimate total phenolic and flavonoid content of extracts. Hydrogen peroxide and 1,1 diphenyl -2-picrylhydrazyl were used to determine in vitro antioxidant activity.ResultsPhytochemical analysis of ethanol extract showed presence of major classes of phytochemicals. Gas chromatography-mass spectrometry results revealed presence of 19 phytoconstituents in hexane extract, 6 in ethyl acetate and 7 compounds in methanolic extract. Methanol extract was found to contain the highest phenolic content and flavonoids. In vitro antioxidant activities of all crude extracts were significant and comparable with the standard ascorbic acid.ConclusionsResults of this study show that the leaves of M. peregrina are the rich source of phenolic compounds that can play an important role in preventing the progression of many diseases.     

In vitro antibacterial activity of leaf extracts of Zehneria scabra and Ricinus communis against Escherichia coli and methicillin resistance Staphylococcus aureus

ObjectiveTo evaluate the antibacterial activities of the crude leaves extracts of Zehneria scabra (Z. scabra) and Ricinus communis (R. communis) against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and methicillin resistance S. aureus.MethodsThe crude powdered leaves of Z. scabra and R. communis were extracted successively by organic solvents in increasing polarity [benzene, chloroform:acetone (1:1), 70% alcohol and distilled water]. The antibacterial susceptibility of the crude leaves extracts of were tested against standard strains of E. coli (ATCC 25922) and S. aureus (ATCC 2923) and clinical isolates of E. coli, S. aureus and methicillin resistance S. aureus using agar well diffusion method.ResultsIn Z. scabra and R. communis leaf extracts, the most sensitive standard strain was S. aureus with an inhibition zone of (14.00±1.20) mm and (15.90±2.13) mm, respectively. The minimum inhibitory concentration (MIC) values of Z. scabra extracts against test organisms ranged from 1.95 mg/mL for extract 3 in clinical and standard strains of S. aureus to 250 mg/mL for extract 1 and 4 in clinical and standard strains of E. coli. The MIC values of R. communis extracts against test organisms ranged from 1.95 mg/mL for extract 2 and 3 standard strains of S. aureus to 250 mg/mL for extract 1 in clinical isolate of E. coli. Most of the minimum bactericidal concentration and MIC values of plant extracts were almost similar particularly in R. communis, or minimum bactericidal concentration equal to one dilution factor less than MIC value of the extracts mainly in Z. scabra.ConclusionsThe potency of plant extracts against test organisms were depend on different organic solvents used. Clinical isolate of bacterial pathogens showed less zones of diameter compared to the standard strains. Gram-positive had wide inhibition zones than Gram-negative bacteria. Further studies should be carried out to isolate the pure compounds and standardization of the methods of plant extracts for an in vitro testing.     

Chemical composition and antioxidant activity of a Lebanese plant Euphorbia macroclada schyzoceras

Objective

To determine the chemical composition, total phenolic and total flavonoid contents of the crude extracts from leaves and stems of a Lebanese plant Euphorbia macroclada schyzoceras (E. macroclada), and to evaluate their antioxidant potential using DPPH, H₂O₂, and chelating of ferrous ions tests.

Methods

Quantification of the total phenolic and total flavonoid contents of the crude extracts from leaves and stems and the antioxidant activities were evaluated using spectrophotometric analyses. The chemical composition has been estimated using different techniques such as IR, LC/MS and NMR.

Results

Ethanolic extract from leaves of E. macroclada was better than aqueous extract and showed higher content in total phenolic and total flavonoid than found in the stems. On the other hand, using DPPH and H₂O₂ tests, this extract from leaves showed higher antioxidant capacity than aqueous extract. However, using the chelating of ferrous ions test, the antioxidant activity of the aqueous extract of both stems and leaves was stronger than that of ethanolic once. The chemical composition of the whole plant showed the presence of some aromatic compounds and fatty acids.

Conclusions

Both ethanolic and water extracts from both parts of this plant are effective and have good antioxidant power. So, this plant can be used in the prevention of a number of diseases related to oxidative stress.     

GC/GCMS analysis of the petroleum ether and dichloromethane extracts of M oringa oleifera roots

ObjectiveTo explore the phytochemical constituents from petroleum ether and dichloromethane extracts of Moringa oleifera (M. oleifera) roots using GC/GC-MS.MethodsA total of 5.11 kg fresh and undried crushed root of M. oleifera were cut into small pieces and extracted with petroleum ether and dichloromethane (20 L each) at room temperature for 2 d. The concentrated extracts were subjected to their GC-MS analysis.ResultsThe GC-MS analysis of the petroleum ether and dichloromethane extracts of M. oleifera roots, which showed promising biological activities, has resulted in the identification 102 compounds. These constituents belong to 15 classes of compounds including hydrocarbons, fatty acids, esters, alcohols, isothiocyanate, thiocyanate, pyrazine, aromatics, alkamides, cyanides, steroids, halocompounds, urea and N-hydroxyimine derivatives, unsaturated alkenamides, alkyne and indole. GC/GC-MS studies on petroleum ether extract of the roots revealed that it contained 39 compounds, belonging to nine classes. Cyclooctasulfur S8 has been isolated as a pure compound from the extract. The major compounds identified from petroleum ether extract were trans-13-docosene (37.9%), nonacosane (32.6%), cycloartenol (28.6%) nonadecanoic acid (13.9%) and cyclooctasulfur S8 (13.9%). Dichloromethane extract of the roots was composed of 63 compounds of which nasimizinol (58.8%) along with oleic acid (46.5%), N-benzyl-N-(7-cyanato heptanamide (38.3%), N-benzyl-N-(1-chlorononyl) amide (30.3%), bis [3-benzyl prop-2-ene]-1-one (19.5%) and N, N-dibenzyl-2-ene pent 1, 5-diamide (11.6%) were the main constituents.ConclusionsThis study helps to predict the formula and structure of active molecules which can be used as drugs. This result also enhances the traditional usage of M. oleifera which possesses a number of bioactive compounds.     

The presence of eucalyptol in Artemisia australis validates its use in traditional Hawaiian medicine

ObjectiveTo identify the major organic compounds of Artemisia australis (A. australis), a plant used in traditional Hawaiian medicine for the treatment of asthma.MethodsThe dichloromethane extract of A. australis was analyzed by gas chromatography-mass spectroscopy and major compounds were identified by a National Institute of Standards and Technology library search and confirmed by peak enhancement.ResultsThe major chemical components of A. australis include eucalyptol, borneol, and caryophyllene.ConclusionsThe presence and biological activity of eucalyptol correlate very well with the usage of this plant in traditional Hawaiian medicine.     

In vitro cytotoxicity of Indonesian stingless bee products against human cancer cell lines

ObjectiveTo screen crude extracts of propolis, bee pollen and honey from four stingless bee species [Trigona incisa (T. incisa)], Timia apicalis, Trigona fusco-balteata and Trigona fuscibasis) native to East Kalimantan, Indonesia for cytotoxic activity against five human cancer cell lines (HepG2, SW620, ChaGo-I, KATO-III and BT474).MethodsAll samples were extracted with methanol, and then subpartitioned with n-hexane and ethyl acetate. Each crude extract was screened at 20 μg/mL for in vitro cytotoxicity against the cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. In addition, four previously shown bioactive components from propolis (apigenin, caffeic acid phenyl ester, kaempferol and naringenin) and two chemotherapeutic drugs (doxorubicin and 5-fluorouracil) were used to evaluate the sensitivity of the cell lines.ResultsOverall, crude extracts from propolis and honey had higher cytotoxic activities than bee pollen, but the activity was dependent upon the extraction solvent, bee species and cell line. Propolis extracts from T. incisa and Timia apicalis showed the highest and lowest cytotoxic activity, respectively. Only the HepG2 cell line was broadly sensitive to the honey extracts. For pure compounds, doxorubicin was the most cytotoxic, the four propolis compounds the least, but the ChaGo-I cell line was sensitive to kaempferol at 10 μg/mL and KATO-III was sensitive to kaempferol and apigenin at 10 μg/mL. All pure compounds were effective against the BT474 cell line.ConclusionsPropolis from T. incisa and Trigona fusco-balteata contain an in vitro cytotoxic activity against human cancer cell lines. Further study is required, including the isolation and characterization of the active antiproliferative agent(s).     

Study of total phenol,flavonoids contents and phytochemical screening of various leaves crude extracts of locally grown Thymus vulgaris

Objective

To prepare various crude extracts using different polarities of solvent and to quantitatively evaluate their total phenol, flavonoids contents and phytochemical screening of Thymus vulgaris collected from Al Jabal Al Akhdar, Nizwa, Sultanate of Oman.

Methods

The leave sample was extracted with methanol and evaporated. Then it was defatted with water and extracted with different polarities organic solvents with increasing polarities. The prepare hexane, chloroform, ethyl acetate, butanol and methanol crude extracts were used for their evaluation of total phenol, flavonoids contents and phytochemical screening study. The established conventional methods were used for quantitative determination of total phenol, flavonoids contents and phytochemical screening.

Results

Phytochemical screening for various crude extracts were tested and shown positive result for flavonoids, saponins and steroids compounds. The result for total phenol content was the highest in butanol and the lowest in methanol crude extract whereas the total flavonoids contents was the highest in methanol and the lowest hexane crude extract.

Conclusions

The crude extracts from locally grown Thymus vulgaris showed high concentration of flavonoids and it could be used as antibiotics for different curable and uncurable diseases.     

Phytochemical screening and antioxidant activity of ethanol extract of Tithonia diversifolia (Hemsl) A. Gray dry flowers

ObjectiveTo evaluate the antioxidant activity of extracts of dried flowers of Tithonia diversifolia (Hemsl) A. Gray (T. diversifolia) dry flower-a shrubby plant belonging to the Asteraceae family and very common in Brazil, providing data to help prevent premature aging skin.MethodsThe tests of phytochemical screening included total phenols, tannins, flavonoids, alkaloids and saponins. The active antioxidant was determined by 2,2-diphenyl-1-picryl-hydrazyl method.ResultsThe phytochemical screening of T. diversifolia dry flowers revealed the presence of phenolic compounds (tannins, flavonoids and total phenols), while alkaloids and saponins were not detected. The IC₅₀ values showed a strong antioxidant activity of the plant extracts.ConclusionsTherefore, this study suggests the possibility of using dry flowers extracts of T. diversifolia for the prevention of cell aging, as was shown to have significant antioxidant activity.     

当归根际土壤水浸液的自毒作用研究及化感物质的鉴定

目的 通过对当归根际土壤提取液的生物学试验和有机化合物的分离鉴定,探讨当归连作障碍与自毒作用的关系。方法 设置水 (CK)、当归根际土水提液 100、125、250、500 mg/mL 共 5 个处理,用于当归自毒作用的生物学实验;气相色谱-质谱联用技术 (GC-MS) 鉴定当归根际土壤有机化合物。结果 125 mg/mL 当归根际土壤水提液能显著抑制当归自身种子发芽率、发芽指数及胚根和胚芽的伸长,且随水提液浓度的升高,这种抑制作用增强。在当归根际土壤水提液中鉴定到17个化合物,包括有机酸、酮、醛、酯和烃类等化感物质,其中很多被报道是化感物质。结论 当归根际土壤水提液对自身种子萌发和幼苗生长具有明显的自毒作用,且自毒效应具有一定的浓度依赖性,推断自毒作用可能是造成当归连作障碍的原因之一。     

Phenolic composition and inhibitory activity of Mangifera indica and Mucuna urens seeds extracts against key enzymes linked to the pathology and complications of type 2 diabetes

ObjectiveTo investigate the phenolic compounds composition and the inhibitory activity of Mangifera indica (M. indica) and Mucuna urens (M. urens) seeds extracts against some key enzymes (α-amylase, α-glucosidase and aldose reductase) implicated in the pathology and complications of type 2 diabetes in vitro.MethodsReverse phase chromatographic quantification of the major flavonoids and phenolic acids in the seeds extracts was carried out using high performance liquid chromatography coupled with diode array detection. The inhibitory activities of the seeds extracts against α-amylase and α-glucosidase were estimated using soluble starch and ρ-nitrophenylglucopyranoside as their respective substrates. Inhibition of aldose reductase activity by the extracts was assayed using partially purified lens homogenate of normal male rat as source of enzyme; inhibition of Fe²⁺-induced lipid peroxidation by extracts was tested in rat pancreas homogenate.ResultsThe chromatography result revealed that extracts of both seeds had appreciable levels of some major flavonoids and phenolic acids of pharmacological importance, including gallic acid, chlorogenic acid, caffeic acid, ellagic acid, catechin, rutin, quercitrin, quercetin and kaempferol. Extracts of both seeds effectively inhibited α-amylase, α-glucosidase and aldose reductase activities in a dose-dependent manner, having inhibitory preference for these enzymes in the order of aldose reductase>α-glucosidase>α-amylase. With lower half-maximal inhibitory concentrations (IC₅₀) against α-amylase, α-glucosidase, and aldose reductase, M. indica had stronger inhibitory potency against these enzymes than M. urens. Extracts of both seeds also inhibited Fe²⁺-induced lipid peroxidation in a dose-dependent pattern, with M. indica being more potent than M. urens.ConclusionsThe results obtained provide support for a possible use of M. indica and M. urens seeds in managing hyperglycemia and preventing the complications associated with it in type 2 diabetes.     

Phytochemical and in vitro biological investigations of methanolic extracts of Enhydra fluctuans Lour.

ObjectiveTo study the phytochemical and biological properties (antioxidant, anthelmintic and thrombolytic) of methanolic extracts of Enhydra fluctuans Lour., a plant belonging to the Asteraceae family.MethodsThe phytochemical evaluation was carried out by qualitative analysis. In vitro antioxidant activity of extract was studied using free radical scavenging assay, ability of reduction, total phenol and total flavonoid contents determination assays. The anthelmintic activity was determined using paralysis and death time of Pheretima posthuma (earthworm) and thrombolytic activity by clot disruption assay.ResultsThe phytochemical evaluation showed significant presence of flavonoids, triterpenes, carbohydrate, reducing sugars, saponins, phenols, diterpenes, protein and tannin. The antioxidant activity was found significant [IC₅₀=(135.20±0.56) μg/mL] as compared to ascorbic acid [(130.00±0.76) µg/mL]. The reducing power was increased with concentration. Total phenol and total flavonoid contents were (153.08±0.38) mg/mL and (172.04±0.56) mg/mL respectively. The paralysis and death time of earthworms for different concentrations of extract were determined and compared with albendazole. The results showed that 10 mg/mL of the crude extract had similar effect with albendazole. Additionally, the crude extract showed a concentration depended relationship with its anthelmintic property. The clot lysis activity of crude extract was compared to the standard streptokinase's clot lysis (40.13%) activity and found significant (31%).ConclusionsThe study proves that the crude methanolic extract of Enhydra fluctuans Lour. has significant antioxidant, anthelmintic and thrombolytic activity containing wide range of phytochemicals.     

HPLC analysis and cell surface receptor binding activities of the crude aqueous and methanolic extract of Sesamum indicum

ObjectiveTo identify the possible functional molecules for therapeutic uses by screening the crude aqueous and methanolic extracts derived from sesame seeds (Sesamum indicum) in vitro.MethodsHigh performance liquid chromatography was used to scan the functional molecules present in the extracts.ResultsThe crude aqueous extracts showed the possibilities to present caffeine and cetirizine or its derivatives like molecules. On the other hand, the crude methanolic extract may contain Loratadine or its derivatives like molecules. Both type of extracts showed hemagglutination inhibition activities in all types of human blood samples tested. However, they showed stronger binding with AB+ blood group than those of A+ and B+ blood.ConclusionsSesame seeds may be considered as a functional food.     

Bioefficacy of Mentha piperita essential oil against dengue fever mosquito Aedes aegypti L

Objective

To assess the larvicidal and repellent potential of the essential oil extracted from the leaves of peppermint plant, Mentha piperita (M. piperita) against the larval and adult stages of Aedes aegypti (Ae. Aegypti).

Methods

The larvicidal potential of peppermint oil was evaluated against early fourth instar larvae of Ae. aegypti using WHO protocol. The mortality counts were made after 24 and 48 h, and LC₅₀ and LC₉₀ values were calculated. The efficacy of peppermint oil as mosquito repellent was assessed using the human-bait technique. The measured area of one arm of a human volunteer was applied with the oil and the other arm was applied with ethanol. The mosquito bites on both the arms were recorded for 3 min after every 15 min. The experiment continued for 3 h and the percent protection was calculated.

Results

The essential oil extracted from M. piperita possessed excellent larvicidal efficiency against dengue vector. The bioassays showed an LC₅₀ and LC₉₀ value of 111.9 and 295.18 ppm, respectively after 24 h of exposure. The toxicity of the oil increased 11.8% when the larvae were exposed to the oil for 48 h. The remarkable repellent properties of M. piperita essential oil were established against adults Ae. aegypti. The application of oil resulted in 100% protection till 150 min. After next 30 min, only 1-2 bites were recorded as compared with 8-9 bites on the control arm.

Conclusions

The peppermint essential oil is proved to be efficient larvicide and repellent against dengue vector. Further studies are needed to identify the possible role of oil as adulticide, oviposition deterrent and ovicidal agent. The isolation of active ingredient from the oil could help in formulating strategies for mosquito control.     

Efficacy of seed extracts of Annona squamosa and Annona muricata (Annonaceae) for the control of Aedes albopictus and Culex quinquefasciatus (Culicidae)

ObjectiveTo evaluate the potential efficacy of seed extracts of Annona squamosa and Annona muricata used as natural insecticides to control adult and larvae of the vectors Aedes albopictus and Culex quinquefasciatus under laboratory conditions.MethodsAqueous and oil extracts of the two plants were prepared from dried seeds. Preliminary identifications of the chemical components of each seed extracts were performed using micro-reactional and GCP techniques. Larvae and adults of Aedes albopictus and Culex quinquefasciatus were collected from the breeding sites in coastal and highlands regions of Madagascar. WHO standardized tests of susceptibility for larvae and imaginal stage of mosquitoes were realized to determine mortality and LC₅₀ of mosquitoes.ResultsChemical identifications showed that these extracts contain alkaloids and flavonoids compounds that probably confer their biological insecticidal proprieties. CPG analysis showed also the presence of various fatty acids. On adult mosquitoes, significant insecticidal effects were observed with both aqueous and oil extracts of the two plant seeds compared to mortality induced by deltamethrin, an insecticide used as reference. Extracts of Annona muricata induced high mortality rate to both species of mosquito compared to extracts of Annona squamosa at all concentrations tested. The LC₅₀ of seed extracts ranged from 1% to 5% for adults and 0.5% to 1% for larvae.ConclusionsThe seed extracts of these two plants may be used as mosquito controlling agents and offer a new approach to a less costly, practical and environmentally friendly control of vector borne diseases.     

Ovicidal activity of Atalantia monophylla (L) Correa against Spodoptera litura Fab. (Lepidoptera: Noctuidae)

ObjectiveTo evaluate the efficacy of Atalantia monophylla (A. monophylla) leaf in different solvent crude extracts and fractions against eggs of Spodoptera litura (S. litura).MethodsHexane, ethyl acetate and chloroform solvent extracts of A. monophylla leaf and 12 fractions from hexane extract were screened at 5.0%, 2.5%, 1.0% and 0.5% for crude extracts and 1 000, 500, 250 and 125 mg/kg for fractions against the eggs of S. litura for the ovicidal activity. LC₅₀ and LC₉₀ were calculated using probit analysis.ResultsHexane crude extract showed maximum ovicidal activity of 61.94% at 5.0% concentration with a correlation value of r²=0.81, and least LC₅₀ value of 3.06%. Hexane extract was fractionated using silica gel column chromatography and 12 fractions were obtained. Fraction 9 was active which showed maximum ovicidal activity of 75.61% at 1 000 mg/kg with the LC₅₀ value of 318.65 mg/kg and LC₉₀ value of 1 473.31 mg/kg. In linear regression analysis, significant and high correlation (r²=0.81%) was seen between concentration and ovicidal activity of hexane crude extracts and its active fraction.ConclusionsAs per our knowledge, this is the first report for ovicidal activity of A. monophylla against S. litura, A. monophylla could be used for the management of S. litura and other insect pests.     

Phytochemical and biological studies of Butia capitata Becc. leaves cultivated in Egypt

ObjectiveTo study the antioxidant and anti-inflammatory activity of Butia capitata (B. capitata) leaf extracts along with phytochemical analysis of the proposed bioactive constituents.MethodsDifferent successive extracts of B. capitata Becc. leaves were prepared with selective organic solvents and screened for their anti-inflammatory activities in tested animals and in-vitro antioxidant effect. An extensive phytochemical investigation of the bioactive extracts through paper chromatography, thin layer chromatography, column chromatography, gas-liquid chromatography (GLC), high pressure liquid chromatography and spectral analysis. GC-Mass, ultraviolet, hydrogen and carbon nuclear magnetic resonance, electron ionization-mass spectrometry, heteronuclear multiple bond correlation and heteronuclear multiple quantum correlation were carried out.ResultsResults showed that different extracts possess promising antioxidant effect and significant anti-inflammatory activity with variable degrees. The results of the phytochemical investigation of the bioactive extracts revealed the presence of volatile substances, lipoidal matter, α-tocopherol, free sugars, polysaccharides and flavonoidal compounds.ConclusionsB. capitata leaf extracts were shown to possess variable antioxidant effect, the most promising was methanol extract. Both polar and non polar extracts were proved to have anti-inflammatory activity, the non polar extract was superior in this respect. The bioactivity of the extracts was ascribed to the presence of flavonoids, sterols and α-tocopherol.     

Phytochemical screening and in vitro bioactivities of the extracts of aerial part of Boerhavia diffusa Linn.

Objective

To investigate the bioactivities of crude n-hexane, ethyl acetate and methanol extracts of aerial part of Boerhavia diffusa Linn. (B. diffusa) and its phytochemical analysis.

Methods

The identification of phytoconstituents and assay of antioxidant, thrombolytic, cytotoxic, antimicrobial activities were conducted using specific standard in vitro procedures.

Results

The results showed that the plant extracts were a rich source of phytoconstituents. Methanol extract showed higher antioxidant, thrombolytic activity and less cytotoxic activity than those of n-hexane and ethyl acetate extracts of B. diffusa. Among the bioactivities, antioxidant activity was the most notable compared to the positive control and thus could be a potential rich source of natural antioxidant. In case of antimicrobial screening, crude extracts of the plant showed remarkable antibacterial activity against tested microorganisms. All the extracts showed significant inhibitory activity against Candida albicuns, at a concentration of 1000 µg/disc.

Conclusions

The present findings suggest that, the plant widely available in Bangladesh, could be a prominent source of medicinally important natural compounds.     

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.     

绶草内生真菌化学成分相关性的研究

目的 探讨绶草内生真菌与其宿主化学成分的相关性,为阐明药用植物真菌与宿主植物产生相同或相似化学成分的机制奠定基础。方法 采用HPLC法对绶草及其内生真菌各提取部位进行色谱分析,并利用SPSS16.0软件对色谱结果进行聚类,得到绶草内生真菌之间化学成分的相关性。结果 绶草内生真菌石油醚提取物的聚类规律不明显;醋酸乙酯提取物及水饱和正丁醇提取物均表现为分离自同一部位的真菌倾向于聚类在同一分支,相同种属的内生真菌同样倾向于聚类在同一分支,且以醋酸乙酯提取物表现最为明显。结论 绶草内生真菌石油醚提取物之间的相关性最小,醋酸乙酯提取物与真菌分离部位相关性最为明显,与真菌的种属同样存在较大的相关性。