Pharmacology and Therapeutics

Permanent URI for this community

http://41.93.62.172:4000/handle/123456789/151

Browse

Browsing Pharmacology and Therapeutics by Subject "Antibacterial"

Now showing 1 - 5 of 5
  • Thumbnail Image
    Item
    (4-methoxy-benzo [1, 3] dioxol-5-yl)-phenylmethanone: An antibacterial benzophenone from Securidaca longepedunculata
    (African Journal of Traditional, Complementary and Alternative Medicines, 2006-03-27) Moshi, Mainen J.
    The dichloromethane extract of Securidaca longepedunculata Fresen yielded a benzophenone, (4-methoxy-benzo[1,3]dioxol-5-yl)-phenylmethanone (1), together with other three known compounds, 1,7-dihydroxy-4-methoxyxanthone (2), benzyl 2-hydroxy-6-methoxybenzoate (3), and methyl 2-hydroxy-6-methoxybenzoate (4). Compound (1) exhibited antibacterial activity against Pseudomonous aeruginosa, and antifungal activity against Aspergillus fumigatus. Compound 2 exhibited antibacterial activity against Staphylococus aureus, and antifungal activity against Aspergillus niger, Aspergillus fumigatus and a Penicillum species. Compounds 3 and 4 were inactive against all the tested bacteria and fungi. These results provide proof of efficacy of the extracts of S.longepedunculata in treating bacterial infections, but further studies should be carried out to ascertain these results with respect to the widely reported traditional use.
  • Thumbnail Image
    Item
    Antibacterial and cytotoxic triterpenoids from Lantana viburnoides ssp. viburnoides var. kisi
    (Spatula DD-Peer Reviewed Journal on Complementary Medicine and Drug Discovery, 2011-12-07) Moshi, Mainen J.
    Lantana viburnoides ssp. var. is used in traditional medicine as a mosquito repellent and sometimes chewed for treatment of gastrointestinal problems. Gastrointestinal problems are varied and may include microbial infections, parasitic infestation; inflammatory bowel disease, malignancies, peptic ulcers, or simply colic pains. This work seeks to establish proof of the concept on safety and efficacy for treatment of bacterial infections. METHODS Root and stem bark ethanol extracts, extract fractions and two isolated compounds were tested for antibacterial activity against five standard Gram positive and two Gram negative bacteria using the broth micro-dilution method. The extracts and isolated compounds were also tested for cytotoxic activity against brine shrimp larvae ( ). RESULTS The stem and root bark ethanol extracts exhibited strong antibacterial activity against (195.3 μg/ml) and (390.6 μg/ml). Camaric acid (1), isolated from the dichloromethane fraction of root bark extract, exhibited antimicrobial activity against (MIC = 19.5 μg/ml) (MIC = 19.5 μg/ml) (MIC = 9.76 μg/ml), (MIC = 4.88 μg/ml), and (MIC = 19.5 μg/ml), and was toxic to the shrimps (LC50 = 4.1 μg/ml). Betulinic acid (2) also from the same fraction exhibited poor anti-bacterial activity against all bacteria tested but showed high cytotoxic activity against brine shrimp larvae (LC50 = 2.4 μg/ml). Conclusion Detection of antibacterial activity and isolation of an antibacterial compound, camaric acid, from extracts of ssp. var. supports the traditional use of extracts of the plant for treatment of gastrointestinal problems. Betulinic acid and camaric acid are already established to have anticancer activity.
  • Thumbnail Image
    Item
    In Vitro Antibacterial and Antifungal Activities of Extracts and Compounds from Uvaria scheffleri
    (Pharmaceutical biology, 2004-09-29) Moshi, Mainen J.
    Petroleum ether, dichloromethane, and ethanolic extracts of the stem bark and leaves of Uvaria scheffleri Diels (Annonaceae) exhibited antifungal activity against Aspergillus niger (wild strain), Aspergillus fumigatus (wild strain), and a Penicillium species (wild strain). The ethanol extract of the stem bark was also active against Candida albicans (Strain H6392). The dichloromethane extract of the leaves showed the highest antifungal activity and in addition it showed antibacterial activity against Staphylococcus aureus (NCTC 6571). Fractionation of the dichloromethane extract of the leaves yielded nine known compounds. They included a 1 : 1 mixture of stigmasterol (1) and β-sitosterol (2), which showed antifungal activity against Candida albicans. Others were 3-farnesylindole (3), 2′,6′-dihydroxy-3′,4′-dimethoxy-chalcone (4), 2′-hydroxy-3′,4′,6′-trimethoxychalcone (5), 5-hydroxy-7,8-dimethoxyflavanone (6), 5,7,8-trimethoxyflavanone (7), and a 3 : 2 mixture of 2′,6′-dihydroxy-4′-methoxychalcone (8) and 5,7-dihydroxyflavone (9). Compound 7 and the mixture of compounds 8 and 9 showed antibacterial activity against Escherichia coli (NCTC 10418, MIC 125 µg/ml) and Staphylococcus aureus (MIC 125 µg/ml), respectively. The mixture of compounds 8 and 9 was also active against Candida albicans (MIC 31.25 µg/ml), Aspergillus niger, Aspergillus fumigatus, and the Penicillium species (MIC 1000 µg/ml). We conclude that Uvaria scheffleri extracts contain compounds with antifungal and antibacterial activity. The activities observed in this study are weak. Based on previous studies, it is being speculated that, possibly, the most active compounds were lost during fractionation. Further work to isolate more antifungal and antibacterial compounds is suggested. Keywords: AntibacterialAntifungalChalconesExtractsFlavanonesFlavonesSterolsUvaria Scheffleri
  • Thumbnail Image
    Item
    Larvicidal, antimicrobial and brine shrimp activities of extracts from Cissampelos mucronata and Tephrosia villosa from coast region, Tanzania
    (BMC Complementary and Alternative Medicine, 2011-04-23) Moshi, Mainen J.
    Background The leaves and roots of Cissampelos mucronata A. Rich (Menispermaceae) are widely used in the tropics and subtropics to manage various ailments such as gastro-intestinal complaints, menstrual problems, venereal diseases and malaria. In the Coast region, Tanzania, roots are used to treat wounds due to extraction of jigger. Leaves of Tephrosia villosa (L) Pers (Leguminosae) are reported to be used in the treatment of diabetes mellitus in India. In this study, extracts from the roots and aerial parts of C. mucronata and extracts from leaves, fruits, twigs and roots of T. villosa were evaluated for larvicidal activity, brine shrimps toxicity and antimicrobial activity. Methods Powdered materials from C. mucronata were extracted sequentially by dichloromethane followed by ethanol while materials from T.villosa were extracted by ethanol only. The extracts obtained were evaluated for larvicidal activity using Culex quinquefasciatus Say larvae, cytotoxicity using brine shrimp larvae and antimicrobial activity using bacteria and fungi. Results Extracts from aerial parts of C. Mucronata exhibited antibacterial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Vibrio cholera, Bacillus anthracis, Streptococcus faecalis and antifungal activity against Candida albicans and Cryptococcus neoformans. They exhibited very low toxicity to brine shrimps and had no larvicidal activity. The root extracts exhibited good larvicidal activity but weak antimicrobial activity. The root dichloromethane extracts from C. mucronata was found to be more toxic with an LC50 value of 59.608 μg/mL while ethanolic extracts from root were not toxic with LC50>100 μg/mL). Ethanol extracts from fruits and roots of T. villosa were found to be very toxic with LC50 values of 9.690 μg/mL and 4.511 μg/mL, respectively, while, ethanol extracts from leaves and twigs of T. villosa were found to be non toxic (LC50>100 μg/mL). Conclusion These results support the use of C. mucronata in traditional medicine for treatment of wounds. Extracts of C. mucronata have potential to yield active antimicrobial and larvicidal compounds. The high brine shrimp toxicity of T. villosa corroborates with literature reports that the plant is toxic to both livestock and fish. The results further suggest that T. villosa extracts have potential to yield larvicidal and possibly cytotoxic compounds. Further studies to investigate the bioactive compounds responsible for the observed biological effects are suggested.
  • Thumbnail Image
    Item
    Some pharmacological properties of extracts of Terminalia sericea roots
    (Journal of Ethnopharmacology, 2005-02-10) Moshi, Mainen J.
    Terminalia sericea Burch. Ex. DC (Combretaceae) extracts are used to treat bacterial infections, diarrhea, and diabetes. Intermediate and polar extracts of the roots exhibited antibacterial activity against Staphylococcus aureus, Escherichia coli, Bacillus anthracis, and Pseudomonas aeruginosa, while the petroleum ether extract was inactive. The extracts were mildly active against Bacillus anthracis and Pseudomonas aeruginosa but exhibited the highest activity against Staphylococcus aureus. They also exhibited antifungal activity against Candida albicans and Aspergillus niger. An 80% aqueous ethanol extract of the roots did not have any effect on blood glucose levels during an oral glucose tolerance test (OGTT), in mice (P > 0.05). With the exception of the dichloromethane and petroleum ether extracts, all the intermediate and polar extracts were toxic to brine shrimps giving LC50 (95% confidence intervals) values ranging from 5.4 (3.5–8.4) to 17.4 (11.4–26.5) μg/ml, while that of cyclophosphamide, a standard anticancer drug, was 16.3 (10.6–25.2) μg/ml. Further work is in progress to isolate and identify active compounds in the extracts.