In vitro antiplasmodial activity of marine sponge Stylissa carteri associated bacteria against Plasmodium falciparum

ObjectiveTo identify the possible antiplasmodial drugs from bacteria associated with marine sponge Stylissa carteri (S. carteri).MethodsThe S. carteri samples were collected from Thondi coast and subjected for enumeration and isolation of associated bacteria. Filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125 μ g/mL) from isolated bacterial strains were screened for antiplasmodial activity against Plasmodium falciparum (P. falciparum) and potential extracts were also screened for biochemical constituents.ResultsTwelve samples of S. carteri were collected and subjected for enumeration and isolation of associated bacteria. The count of bacterial strains were maximum in November 2007 (34 × 10⁴ CFU/g) and the average count was maximum during the monsoon season (203 × 10³ CFU/g). Thirty two morphologically different bacterial strains were isolated from S. carteri and the ethyl acetate bacterial extracts were screened for antiplasmodial activity against P. falciparum. The antiplasmodial activity of a strain THB17 (IC₅₀ 20.56 μ g/mL) extract is highly comparable with the positive control chloroquine (IC₅₀ 19.59 μ g/mL) and 13 bacterial extracts which showed IC₅₀ value of more than 100 μ g/mL. Statistical analysis reveals that, significant in vitro antiplasmodial activity (P<0.05) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes showed no morphological changes in erythrocytes by the ethyl acetate extract of bacterial strains after 48 h of incubation. The in vitro antiplasmodial activity might be due to the presence of reducing sugars and alkaloids in the ethyl acetate extracts of bacterial strains.ConclusionsThe ethyl acetate extract of THB17 possesses lead compounds for the development of antiplasmodial drugs.     

In vitro antiplasmodial activity of marine sponge Clathria vulpina extract against chloroquine sensitive Plasmodium falciparum

ObjectiveTo explore the antiplasmodial potential of marine sponge Clathria vulpina (C. vulpina) against chloroquine sensitive Plasmodium falciparum (P. falciparum).MethodsThe marine sponge C. vulpina was collected from Thondi coast, authenticated and subjected for extraction by soaking in ethanol:water mixture (3:1 ratio). The percentage of extract was calculated. Filter sterilized extracts (100, 50, 25, 12.5, 6.25, 3.125 μg/mL) were screened for antiplasmodial activity against chloroquine sensitive P. falciparum. The extract was also tested for its hemolytic activity.ResultsThe percentage yield of extract of C. vulpina was found to be 4.8%. The crude extract of C. vulpina showed excellent antiplasmodial activity (IC₅₀=14.75 μg/mL) which was highly comparable to the positive control chloroquine (IC₅₀=7 μg/mL). Statistical analysis reveals that the significant antiplasmodial activity (P<0.05) was observed between the concentrations and the time of exposure. The chemical injury to erythrocytes was also carried out, which showed that there were no morphological changes in erythrocytes by the ethanolic extracts of sponges after 48 h of incubation. The extract showed slight hemolytic activity which almost equal to chloroquine at 100 μg/mL concentration (1.023%).ConclusionsThe marine sponge C. vulpina can be used as a putative antiplasmodial drug after completing successful clinical trials.     

Antimicrobial, antiplasmodial, haemolytic and antioxidant activities of crude extracts from three selected Togolese medicinal plants

ObjectiveTo investigate the antioxidant, antimicrobial, antiplasmodial, acute toxicity and haemolytic activities of methanolic extracts of three plants. Phytochemical analysis to determine the phenolic contents was also carried out.MethodsThe 2,2-diphenyl-1-picryl-hydrazyl (DPPH) free radical scavenging, NCCLS broth microdilution and Plasmodium Lactate Dehydrogenase (pLDH) assays were used to determine antioxidant, antimicrobial and antiplasmodial activities, respectively. Haemolysis assay was conducted on A⁺ human red blood cells and acute toxicity on male Swiss albino mice. Phenolics were quantitatively determined using spectrophotometric methods.ResultsThe DPPH assay yielded interesting antioxidant activities of methanolic extract of Parinari curatellifolia (P. curatellifolia) and Entada africana (E. africana) (IC₅₀ were 0.20±0.01 μg/mL and 0.47±0.01 μg/mL, respectively). This activity was highly correlated with phenolic contents of extracts. The antimicrobial tests displayed minimal inhibitory concentrations (MICs) values ranging from 0.90 to 1.80 mg/mL for Serratia marcescens (S. marcescens) the most susceptible bacterial strain. MIC value was 1.20 mg/mL for susceptible fungal strains including Mucor rouxi (M. rouxi), Fusarium oxyporum (F. oxyporum) and Rhizopus nigricans (R. nigricans). pLDH assay showed moderate antiplasmodial activity of Balanites aegyptiaca (B. aegyptiaca) (IC₅₀ = 24.56±3.45 μg/mL), however this extract was highly haemolytic and toxic in mice (LD₅₀ = 625±128 mg/kg).ConclusionsOur results support in part the use of the selected plants in the treatment of microbial infections. In addition the plant showed interesting antioxidant activity that could be useful in the management of oxidative stress.     

In vitro antiplasmodial activity of ethanolic extracts of South Indian medicinal plants against Plasmodium falciparum

ObjectiveTo explore the antiplasmodial potential ofCatharanthus roseus L (C. roseus), Coccinea grandis (C. grandis), Thevetia peruviana (T. peruviana), Prosopis juliflora (P. juliflora), Acacia nilotica (A. nilotica), Azadirachta indica (A. indica) (Abr. Juss) and Morinda pubescens (M. pubescens).MethodsThe C. roseus L, C. grandis, T. peruviana, P. juliflora, A. nilotica, A. indica (Abr. Juss) and M. pubescens were collected from Ramanathapuram District, Tamil Nadu, India and the extraction was carried out in ethanol. The filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125 μg/mL) were tested for antiplasmodial activity against Plasmodium falciparum. The phytochemical constituents in the potential extracts were also detected.ResultsOf the selected plants species, the bark extract of A. indica (Abr. Juss) showed excellent antiplasmodial activity (IC₅₀ 29.77 μg/mL) followed by leaf extract of A. indica (Abr. Juss) (IC₅₀47.20 μg/mL) and leaf extract of C. roseus L (IC₅₀49.63 μg/mL). The leaf, bark and flower extracts of P. juliflora showed IC₅₀values of more than 100 μg/mL. Statistical analysis reveals significant antiplasmodial activity (P<0.01) between the concentrations and time of exposure. Additionally, no chemical injury was found in the erythrocytes incubated with the ethanolic extract of all the tested plants. The in vitro antiplasmodial activity might be due to the presence of alkaloids, glycosides, carbohydrates, flavonoids, phenols, saponins, triterpenoids, proteins and tannins in the ethanolic extracts of the tested plants.ConclusionsThe ethanolic bark extracts of A. indica (Abr. Juss) possess lead compounds for the development of antiplasmodial drugs.     

In vitro antiplasmodial effect of ethanolic extracts of traditional medicinal plant Ocimum species against Plasmodium falciparum

ObjectiveTo identify the possible antiplasmodial compounds from leaf, stem, root and flower extracts of Ocimum canum (O. canum), Ocimum sanctum (O. sanctum) and Ocimum basilicum (O. basilicum).MethodsThe O. canum, O. sanctum and O. basilicum were collected from Ramanathapuram District, Tamil Nadu and the extraction was carried out in ethanol. The filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125 μg/mL) of leaf, stem, root and flower extracts of O. canum, O. sanctum and O. basilicum were tested for antiplasmodial activity against Plasmodium falciparum (P. falciparum). The potential extracts were also tested for their phytochemical constituents.ResultsThe leaf extract of O. sanctum showed excellent antiplasmodial activity (IC₅₀ 35.58 μg/mL) followed by leaf extract of O. basilicum (IC₅₀ 43.81 μg/mL). The leaf extract of O. canum, root extracts of O. sanctum and O. basilicum, the stem and flower extracts of all the three tested Ocimum species showed IC₅₀ values between 50 and 100 μg/mL. Statistical analysis reveals that, significant antiplasmodial activity (P <0.01) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes was also carried out and it shows that, there were no morphological changes in erythrocytes by the ethanolic extract of O. canum, O. sanctum and O. basilicum. The in vitro antiplasmodial activity might be due to the presence of alkaloids, glycosides, flavonoids, phenols, saponins, triterpenoids, proteins, resins, steroids and tannins in the ethanolic extracts of tested plants.ConclusionsThe ethanolic leaf extracts of O. sanctum possess lead compounds for the development of antiplasmodial drugs.     

Estimation of total phenolic content,cytotoxicity and in–vitro antioxidant activity of stem bark of Moringa oleifera

ObjectiveTo assess the phytochemical constituents, total phenolic content, cytotoxicity and in-vitro antioxidant activity of stem bark extracts of Moringa oleifera (M. oleifera) (Moringaceae).MethodsBrine shrimp lethality (BSL) bioassay was used to investigate the cytotoxic effects. DPPH and nitric oxide radical scavenging activity was used to demonstrate antioxidant activity.ResultsPhytochemical analysis revealed the presence of tannins, flavonoids, steroids and alkaloids. The LC₅₀ values were obtained for extracts as 850 μg/mL for petroleum ether extract, 800 μg/mL for chloroform extract and 900 μg/mL for methanol extract. The total phenolic content of the methanolic extract was 50.72% w/w, equivalent to gallic acid. Petroleum ether, chloroform and methanolic extracts of M. oleifera and standard ascorbic acid were found to be scavenger of DPPH radical with an IC₅₀ of 124.75, 112.08, 54.34 and 13.86 μg/mL, respectively. Methanolic extract was found to be good scavenger of DPPH radical. Petroleum ether, chloroform, ethyl acetate soluble fraction of methanolic extracts of M. oleifera and ascorbic acid were found to be scavenger of nitric oxide radical with an IC₅₀ of 93.32, 65.12, 54.83 and 12.59 μg/mL, respectively. Ethyl acetate soluble fraction was found to be good scavenger of nitric oxide radical.ConclusionsIt can be concluded that the crude extracts of M. oleifera is a potential source of natural antioxidants, and this justifies its uses in folkloric medicines.     

Antioxidant activity and free radical scavenging activities of Streptomyces sp.strain MJM 10778

Objective:To investigate the antioxidant activity of soil-borne aetinobacteria.Methods:The total phenolic contents,the level of antioxidant potential by DPPH radical scavenging activity,MO scavenging activity,and ABTS radical scavenging activity in ethyl acelale extract were determined.Results:The 16 S rDNA sequencing analysis revealed that Streptomyces sp.strain MJM 10778.which was isolated from Hambak Mountain.Korea,has 99.9% similarity to Streptomyces misionensis(S.misionenis) NBRC 13063.The physiological and the morphological test revealed that the strain MJM 10778 has different characteristics from the strain NBRC.13063.The entire antioxidant assay with the ethyl acelale extract displayed good radical scavenging activity.The IC_(50) values of the strain MJM 10778 extract on DPPH,.NO.and ABTS radicals were identified to he 92.8 μg/mL,0.02 μg/ml,and 134.9 μg/mL,respectively.The ethyl acetate extract of the strain MJM 10778 showed an 81.500% of cell viability at 100 μg/mL in Raw264.7cell viability assay.Conclusions:The results obtained suggesl that the ethyl acetate extract of Streptomyces sp.strain MJM 10778 could be considered as a potential source of drug for the diseases that is caused by free radicals with its anti-oxidant activities and low cytotoxicity.     

Antioxidant activity and identification of bioactive compounds from leaves of Anthocephalus cadamba by ultra–performance liquid chromatography/electrospray ionization quadrupole time of flight mass spectrometry

ObjectiveTo evaluate the antioxidant potential of different extract/fractions of Anthocephalus cadamba (A. cadamba) (Roxb.) Miq. (Rubiaceae) and study the tentative identification of their active constituents.MethodsThe extract/fractions were screened for antioxidant activity using various in vitro assays viz. DPPH assay, ABTS assay, superoxide anion radical scavenging assay, reducing power assay and plasmid DNA nicking assay. Total phenolic content of extract/fractions was determined by colorimetric method. An ultra–performance LC-electrospray-quadrupole-time of flight mass spectrometry method was used to analyse the active constituents of extract/fractions of A. cadamba.ResultsThe ethyl acetate fraction was found to be most active fraction in all the assays as compared to other extract/fractions. The IC₅₀ value of ethyl acetate fraction (ETAC fraction) was 21.24 μg/mL, 1.12 μg/mL, 9.68 μg/mL and 57.81 μg/mL in DPPH assay, ABTS assay, reducing power assay and superoxide scavenging assay respectively. All the extract/fractions also showed the potential to protect the plasmid DNA (pBR322) against the attack of hydroxyl radicals generated by Fentońs reagent. The bioactive compounds were identified by UPLC-ESI-QTOF-MS, by comparing the mass and λ_max with literature values.ConclusionsThe potential of the extract/fractions to scavenge different free radicals in different systems indicated that they may be useful therapeutic agents for treating radical-related pathologic damage.     

Anti-oxidant and anti-inflammatory activity of leaf extracts and fractions of Mangifera indica

ObjectiveTo evaluate the anti-oxidant and anti-inflammatory activity of leaf extracts and fractions of Mangifera indica in in vitro conditions.MethodsIn vitro DPPH radical scavenging activity and lipoxygenase (LOX) inhibition assays were used to evaluate the anti-oxidant and anti-inflammatory activities respectively. Methanolic extract (MEMI), successive water extract (SWMI) and ethyl acetate fraction (EMEMI), n-butanol fraction (BMEMI) and water soluble fraction (WMEMI) of methanolic extract were evaluated along with respective reference standards.ResultsIn in vitro DPPH radical scavenging activity, the MEMI, EMEMI and BMEMI have offered significant antioxidant activity with IC₅₀ values of 13.37, 3.55 and 14.19 μg/mL respectively. Gallic acid, a reference standard showed significant antioxidant activity with IC₅₀ value of 1.88 and found to be more potent compared to all the extracts and fractions. In in vitro LOX inhibition assay, the MEMI, EMEMI and BMEMI have showed significant inhibition of LOX enzyme activity with IC₅₀ values of 96.71, 63.21 and 107.44 μg/mL respectively. While, reference drug Indomethacin also offered significant inhibition against LOX enzyme activity with IC₅₀ of 57.75. Furthermore, MEMI was found to more potent than SWMI and among the fractions EMEMI was found to possess more potent antioxidant and anti-inflammatory activity.ConclusionsThese findings suggest that the MEMI and EMEMI possess potent anti-oxidant and anti-inflammatory activities in in vitro conditions.     

Evaluation of larvicidal activity of medicinal plant extracts against three mosquito vectors

ObjectiveTo evaluate the mosquito larvicidal activity of plant extracts.MethodsThe hexane, chloroform, ethyl acetate, acetone, and methanol leaf, flower and seed extracts of Abrus precatorius (A. precatorius), Croton bonplandianum (C. bonplandianum), Cynodon dactylon (C. dactylon), Musa paradisiaca (M. paradisiaca) and Syzygium aromaticum (S. aromaticum) were tested against fourth instar larvae of Anopheles vagus (An. vagus), Armigeres subalbatus (Ar. subalbatus) and Culex vishnui (Cx. vishnui).ResultsThe highest larval mortality was found in seed ethyl acetate extracts of A. precatorius and leaf extracts of C. bonplandianum, flower chloroform and methanol extracts of M. paradisiaca, and flower bud hexane extract of S. aromaticum against An. vagus with LC₅₀ values of 19.31, 39.96, 35.18, 79.90 and 85.90 μg/mL; leaf ethyl acetate and methanol extracts of C. dactylon, flower methanol extract of M. paradisiaca, flower bud methanol extract of S. aromaticum against Ar. subalbatus with LC₅₀ values of 21.67, 32.62, 48.90 and 78.28 μg/mL, and seed methanol of A. precatorius, flower methanol extract of M. paradisiaca, flower bud hexane extract of S. aromaticum against Cx. vishnui with LC₅₀ values of 136.84, 103.36 and 149.56 μg/mL, respectively.ConclusionsThese results suggest that the effective plant crude extracts have the potential to be used as an ideal ecofriendly approach for the control of disease vectors. This study provides the first report on the larvicidal activity of crude solvent extracts of different mosquitoes.     

Larvicidal and adulticidal potential of medicinal plant extracts from south India against vectors

ObjectiveTo determine the larvicidal and adulticidal activities of hexane, ethyl acetate and methanol extracts of Momordica charantia (M.charantia), Moringa oleifera(M. oleifera), Ocimum gratissimum (O. gratissimum), Ocimum tenuiflorum (O. tenuiflorum), Punica granatum(P. granatum) and Tribulus terrestris (T. terrestris) against Culex gelidus (Cx. gelidus) and Culex quinquefasciatus (Cx. quinquefasciatus).MethodsBioassay test was carried out by WHO method for determination of larvicidal and adulticidal activity against mosquitoes.ResultsAll plant extracts showed moderate larvicidal and adulticidal activities, however the effective larval mortality was found in the leaf ethyl acetate and methanol extract of O. gratissimum and bark methanol extract of M. oleifera against Cx.gelidus with LC₅₀ values of 39.31, 66.28, and 21.83 μg/mL respectively, and methanol extract of O. gratissimum, O. tenuiflorum and P. granatum against Cx. quinquefasciatus with LC₅₀ values of 38.47, 24.90 and 67.20 μg/mL, respectively. The adult exposed for 1 h and mortality was recorded at 24 h recovery period. Above 90% mortality was found in the ethyl acetate and methanol extract of all experimental plants at the concentrations of 500 μg/mL.ConclusionsThe present results suggest that the medicinal plant extracts provided an excellent potential for controlling Cx. gelidus and Cx. quinquefasciatus.     

Phenolic and flavonoid contents and anti-oxidative potential of epicarp and mesocarp of Lagenaria siceraria fruit: a comparative study

ObjectiveTo conduct a comparative analysis of the phenolic and flavonoid contents and anti-oxidative potential of epicarp and mesocarp of Lagenaria siceraria fruit.MethodsThe dried methanolic extracts of mesocarp and epicarp of the fruit and their hexane, chloroform, ethyl acetate, n-butanolic and aqueous fractions were subjected to antioxidant assays including ferric reducing antioxidant potential, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid, reducing power capacity, 2,2-diphenyl-1-picrylhydrazyl, lipid peroxidation inhibitory and phosphomolybdate assays. Total phenolic and flavonoid contents were also determined.ResultsEthyl acetate fractions of epicarp and mesocarp had considerable amounts of phenolics (243.50 and 109.50 μg/mL of gallic acid equivalents, respectively). 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity of ethyl acetate fractions of both the plant parts showed higher activity than vitamin C with IC₅₀ (0.75 and 3.91 mg, respectively). In phosphormolybdate assay, the hexane fractions of both the parts showed highest activity [1.16 and 2.99 μg/mL of ascorbic acid equivalents (AAE) for epicarp and mesocarp, respectively], mesocarp being much potent than epicarp. The n-butanolic fraction of mesocarp also showed much higher activity (1.13 μg/mL AAE) than that of epicarp (0.74 μg/mL AAE), while the chloroform and ethyl acetate fractions of epicarp were also considerably potent. In ferric reducing antioxidant potential assay, the chloroform fractions of both the fruit parts were most active. The hexane fractions of both the parts showed highest activity in reducing power assay, epicarp being more potent than mesocarp. In 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid assay, the antioxidant activities of ethyl acetate and chloroform fractions of both the parts were comparable to gallic acid and vitamin C. In lipid peroxidation inhibitory assay, all the samples were moderate to good activity sustainable over the period of 72 h, indicating the presence of both slow and fast releasing antioxidants.ConclusionsThe findings of the study suggest that epicarp is a better source of antioxidants than the mesocarp, and the ethyl acetate fractions of both the parts contain higher contents of antioxidants.     

Evaluation of antioxidant,in vitro cytotoxicity of micropropagated and naturally grown plants of Leptadenia reticulata (Retz.) Wight & Arn.-an endangered medicinal plant

ObjectiveTo evaluate the antioxidant and anti proliferative potential of different solvent extract of micropropagated and naturally grown plants of Leptadenia reticulata against various cancer cell lines.MethodsIn this study different extract were tested for cytotoxicity against human breast adenocarcinoma cell line MCF-7, human colon adenocarcinoma grade II cell line HT-29 and non cancer skeletal muscle cell line L6 through 3-(4, 5–dimethyl thiazol–2–yl)–5–diphenyl tetrazolium bromide assay. The total antioxidant potential was estimated by three different antioxidant model diphenylpicrylhydrazyl free radical scavenging activity, H₂O₂ scavenging activity and FeCl₃ reducing activity.ResultsThe ethyl acetate extract of both naturally grown plant and tissue cultured plant exhibited significant cytotoxicity with IC₅₀ values of 21 µg/mL, 26 µg/mL and 22 µg/mL; 20 µg/mL, 30 µg/mL and 18 µg/mL respectively against three cell lines. The diphenylpicrylhydrazyl free radical scavenging activity was found to be highest with IC₅₀ value of 267.13 µg/mL in ethyl acetate extract. The methanolic extract exhibited moderate antioxidant activity with IC₅₀ value of 510.15 µg/mL. A highly positive correlation was observed between the antioxidant potential and cytotoxic activity of the plant.ConclusionsThe strong cytotoxicity of ethyl acetate extract revealed anti carcinogenic potential of the plant which supports its traditional use as medicine. The present investigation is new to literature till date and will provide better scientific basis for future pharmacological, in vivo studies and novel source of pure bioactive compounds having anti cancer properties in this plant.     

Phytochemical and biological activities of Bituminaria bituminosa L. (Fabaceae)

ObjectiveTo investigate the phytochemical composition, the antioxidant and antibacterial activities of Bituminaria bituminosa L. (Fabaceae) (B. bituminosa).MethodsThe aerial parts of B. bituminosa yielded two compounds. The structures of these compounds were determinated using UV, ¹H-NMR and ¹³C-NMR experiments and comparison of their spectroscopic properties with literature data. The antibacterial activity of the extracts (CH₂Cl₂, ethyl acetate and n-BuOH) was determinated using disk diffusion method against standard and clinical strains. Antioxidant potential of n-BuOH extract was evaluated through two methods: DPPH and cupric ion reducing antioxidant capacity assay.ResultsThe n-BuOH extract from B. bituminosa yielded the isolation of isoflavone and flavone. The extracts CH₂Cl₂, ethyl acetate and n-BuOH demonstrated significant antibacterial activities. CH₂Cl₂ extract showed the maximum antibacterial activity with high concentration of 2 mg/mL against Staphylococcus aureus ATCC 29213, Klebsiella pneumonia and Escherichia coli ATCC 25922 (20.45 mm, 16.41 mm and 15.74 mm inhibition zone, respectively). The value IC₅₀ was 0.26 μg/mL for n-BuOH extract using DPPH method. Whereas the E% value was 0.10 L/mg every centimeter for cupric ion reducing antioxidant capacity assay.ConclusionsThe phytochemical study of B. bituminosa revealed the presence of isoflavone (daidzin) and flavone (isoorientin) and identified for the first time in this specie. The antibacterial activity of the plant B. bituminosa is certainly related to its chemical content. The n-BuOH extract showed a significant antioxidant activity.     

In vitro antiplasmodial activity of spiro benzofuran compound from mangrove plant of Southern India

ObjectiveTo find out the in vitro antipalsmodial activities of mangrove leaf extracts.MethodsIn vitro antiplasmodial assay was carried out with 13 different mangrove plants. Column chromatography was performed with the most potent Agecerious corniculatum (A. corniculatum) by using various solvent extractions. GC-MS was also preformed with the most potent ethanolic fraction of the A. corniculatum extract.ResultsOf the 13 mangroves plants, A. corniculatum showed maximum percentage of parasitemia suppression (94.98 ± 1.16)%. Column chromatography was performed with A. corniculatum with different solvents and the methanolic extract showed maximum percentage (99.73±1.63)% of parasitemia inhibition at 150 μg/mL concentration with the IC₅₀ value of (29.28±3.23) μg/mL concentration. The results of the GC-MS analysis observed that, the most potent methanolic extract showed maximum retention time (30.687 RT) and the chemical class was identified as Spiro [benzofuran-2(3 H), 1′(3 cyclohexane)-2′,3-dione, 7-chloro-4′,6] which was responsible for the antiplasmodial activity.ConclusionsIt is concluded from the present study that, the chemical constituents of A. corniculatum collected from Pichavaram mangrove forest can be used as a putative antiplasmodial drugs in future.     

Phytochemical screening,anti-oxidant activity and in vitro anticancer potential of ethanolic and water leaves extracts of Annona muricata (Graviola)

ObjectiveTo determine the phytochemical composition, antioxidant and anticancer activities of ethanolic and water leaves extracts of Annona muricata (A. muricata) from the Eastern Uganda.MethodsPhytochemical screening was conducted using standard qualitative methods and a Chi-square goodness of fit test was used to assign the relative abundance of the different phytochemicals. The antioxidant activity was determined using the 2, 2-diphenyl-2-picrylhydrazyl and reducing power methods whereas the in vitro anticancer activity was determined using three different cell lines.ResultsPhytochemical screening of the extracts revealed that they were rich in secondary class metabolite compounds such as alkaloids, saponins, terpenoids, flavonoids, coumarins and lactones, anthraquinones, tannins, cardiac glycosides, phenols and phytosterols. Total phenolics in the water extract were (683.69±0.09) μg/mL gallic acid equivalents (GAE) while it was (372.92±0.15) μg/mL GAE in the ethanolic extract. The reducing power was 216.41 μg/mL in the water extract and 470.51 μg/mL GAE in the ethanolic extract. In vitro antioxidant activity IC₅₀ was 2.0456 mg/mL and 0.9077 mg/mL for ethanolic and water leaves extracts of A. muricata respectively. The ethanolic leaves extract was found to be selectively cytotoxic in vitro to tumor cell lines (EACC, MDA and SKBR3) with IC₅₀ values of 335.85 μg/mL, 248.77 μg/mL, 202.33 μg/mL respectively, while it had no cytotoxic effect on normal spleen cells. The data also showed that water leaves extract of A. muricata had no anticancer effect at all tested concentrations.ConclusionsThe results showed that A. muricata was a promising new antioxidant and anticancer agent.     

Adulticidal activity of Ageratum houstonianum Mill. (Asteraceae) leaf extracts against three vector mosquito species (Diptera: Culicidae)

ObjectiveTo determine the intrinsic toxicity of hexane, ethyl acetate and methanol crude extracts of Ageratum houstonianum leaves against adult Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus mosquitoes.MethodsBioassay was performed in 2-day-old laboratory reared unfed adult female mosquitoes by topical application at concentrations of 0.01, 0.05, 0.10, 0.25 and 0.50 μg/mg female adult mosquito.ResultsAedes aegypti was found to be more susceptible to ethyl acetate and hexane extracts with LD₅₀ value of 0.10 μg/mg, and both Anopheles stephensi and Culex quinquefasciatus were susceptible to methanol extract with LD₅₀ values of 0.12 μg/mg female adult mosquito.ConclusionsThe results show promising adulticidal activity on topical application and further studies followed by in-depth laboratory and field bioassays are needed to screen, isolate and purify bioactive phytochemical constituents or compounds.     

Efficacy of larvicidal and pupicidal activity of Catharanthus roseus aqueous and solvent extracts against Anopheles stephensi Liston and Culex quinquefasciatus Say (Diptera: Culicidae)

ObjectiveTo investigate the larvicidal and pupicidal activities of aqueous, ethyl acetate and methanol extracts of Catharanthus roseus (C. roseus) against malaria and filariasis vectors.MethodsThe larvicidal and pupicidal activities of C. roseus leaf extracts were tested against the fourth instar larvae and pupae of Anopheles stephensi (An. stephensi) and Culex quinquefasciatus (Cx. quinquefasciatus). The mortality was observed after 24 and 48 h post the treatment. The data were subjected to probit analysis to determine the lethal concentrations (LC₅₀ and LC₉₀) at which 50% and 90% of the treated larvae or pupae of the tested species were killed.ResultsThe larval and pupal mortality were observed after 24 and 48 h of exposure of aqueous, ethyl acetate and methanol extracts of C. roseus; no mortality was observed in the control group. The LC₅₀ values against the fourth-instar larvae of An. stephensi were 68.62 and 72.04 mg/mL for the aqueous extract, 82.47 mg/mL for the ethyl acetate extract, and 78.80 and 86.64 mg/mL for the methanol extract, while the aqueous, ethyl acetate and methanol extracts had LC₅₀ values of 85.21, 76.84 and 94.20 mg/mL against the fourth-instar larvae of Cx. quinquefasciatus. The aqueous, ethyl acetate and methanol extracts had LC₅₀ values of 118.08, 182.47 and 143.80 mg/mL against the pupae of An. stephensi and 146.20, 226.84 and 156.62 mg/mL against the pupae of Cx. quinquefasciatus, respectively.ConclusionsThe aqueous and methanol extracts of C. roseus leaves had an excellent potential to control the malarial vector An. stephensi and filariasis vector Cx. quinquefasciatus.     

In vitro antiplasmodial activity of crude extracts from Togolese medicinal plants

ObjectiveTo investigate the antimalarial effect of a few plants in Togo folk medicine.MethodsAfter ethnobotanical survey, Opilia celtidifolia, Pavetta corymbosa (P. corymbosa) and Tamarindus indica (T. indica) were selected for screening. In vitro antimalarial tests were performed on crude extracts against fresh clinical isolates of Plasmodium falciparum using the semi microtest.ResultsDifferent IC₅₀ values of the extracts ranged from 2.042 to 100.000 μg/mL. According to the results, the methanol extract of aerial part of P. corymbosa followed by aqueous extract of fruit of T. indica were the most active (IC₅₀ of 2.042 and 4.786 μg/mL, respectively). Qualitative test revealed the presence of alkaloids in the leaves of P. corymbosa that may be responsible for the activity of the plant.ConclusionsOur study provides scientific evidence for usage of plant in the folk medicine, and further studies are needed for identification and purification of the active principles.     

In vitro screening for acetylcholinesterase inhibition and antioxidant activity of medicinal plants from southern Africa

ObjectiveTo determine the acetylcholinesterase inhibitory (AChEI) and antioxidant activity of the ethyl acetate and methanol extracts of 12 traditional medicinal plants used in the treatment of neurological disorders.MethodsAChEI activity was determined spectrophotometrically using the Ellman's colorimetric method. Antioxidant activity was carried out by determining the ability of the extracts to scavenge 2,2-diphenyl-1-picryl hydrazyl (DPPH) and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radicals. The levels of total phenols, flavonoids and flavonols were determined quantitatively using spectrophotometric methods.ResultsAChEI was observed to be dose-dependent. Lannea schweinfurthii (L. schweinfurthii) (Engl.) Engl. and Scadoxus puniceus (S. puniceus) (L.) Friis &; I. Nordal. root extracts showed the lowest IC₅₀ value of 0.000 3 mg/mL for the ethyl acetate extracts while Zanthoxylum davyi (Z. davyi) (I. Verd.) P.G. Watermann had the lowest IC₅₀ value of 0.01 mg/mL for the methanol extracts in the AChEI assay. The roots of Piper capense (P. capense) L.f., L. schweinfurthii, Ziziphus mucronata (Z. mucronata) Willd., Z. davyi and Crinum bulbispermum (C. bulbispermum) (Burm.f.) Milne-Redh. &; Schweick. showed noteworthy radical scavenging activity and good AChEI activity.ConclusionsFive plants show good antioxidant and AChEI activity. These findings support the traditional use of the plants for treating neurological disorders especially where a cholinesterase mechanism and reactive oxygen species (ROS) are involved.