Microbiological and chemical analysis of neem (Azadirachta indica A. Juss) extracts: new data on antimicrobial activity

E. Coventry, Eunice Jessie Allan

    Research output: Contribution to journalArticle

    39 Citations (Scopus)

    Abstract

    The antimicrobial effects of extracts of neem seed (Azadirachta indica A. Juss.) were investigated using microbial growth inhibition assays. A laboratory-prepared neem. seed extract along with a commercially available formulated product, were characterized using HPLC, and shown to be effective against a range of bacteria in an agar diffusion assay. The active ingredient, i.e., the unformulated seed extract of the commercial product, also showed activity and this was further investigated in a biochromatogram, using the sensitive bacterium Bacillus mycoides. Results showed antibacterial activity as three discrete inhibition zones that did not correspond to the R-f of the major neem. metabolites, azadirachtin, nimbin and salannin. This suggests that these compounds were not antibacterial. The colony radial growth rates of the fungal pathogens that cause 'take-all' and 'snow mould' disease were both significantly affected when the commercial, unformulated, neem seed extract was incorporated into the growth medium. Experiments in liquid culture suggested that the effect was fungistatic. Conidial germination of the commercially important obligate pathogen Sphaerotheca fuliginea (powdery mildew) was reduced to 11%. The results show that neem. seed extracts possess antimicrobial activity with notable effects on some fungal phytopathogens. This work demonstrates that neem seed extracts have potential for controlling both microbial and insect pests.

    Original languageEnglish
    Pages (from-to)441-450
    Number of pages9
    JournalPhytoparasitica
    Volume29
    Issue number5
    Publication statusPublished - 2001

    Keywords

    • neem
    • antibacterial
    • antifungal
    • biochromatogram
    • phytopathogens
    • azadirachtin
    • PERFORMANCE LIQUID-CHROMATOGRAPHY
    • SEEDS
    • TREE
    • OIL

    Cite this

    Microbiological and chemical analysis of neem (Azadirachta indica A. Juss) extracts: new data on antimicrobial activity. / Coventry, E.; Allan, Eunice Jessie.

    In: Phytoparasitica, Vol. 29, No. 5, 2001, p. 441-450.

    Research output: Contribution to journalArticle

    @article{b1d59e4d7e9d42a782d5652b8a77f89b,
    title = "Microbiological and chemical analysis of neem (Azadirachta indica A. Juss) extracts: new data on antimicrobial activity",
    abstract = "The antimicrobial effects of extracts of neem seed (Azadirachta indica A. Juss.) were investigated using microbial growth inhibition assays. A laboratory-prepared neem. seed extract along with a commercially available formulated product, were characterized using HPLC, and shown to be effective against a range of bacteria in an agar diffusion assay. The active ingredient, i.e., the unformulated seed extract of the commercial product, also showed activity and this was further investigated in a biochromatogram, using the sensitive bacterium Bacillus mycoides. Results showed antibacterial activity as three discrete inhibition zones that did not correspond to the R-f of the major neem. metabolites, azadirachtin, nimbin and salannin. This suggests that these compounds were not antibacterial. The colony radial growth rates of the fungal pathogens that cause 'take-all' and 'snow mould' disease were both significantly affected when the commercial, unformulated, neem seed extract was incorporated into the growth medium. Experiments in liquid culture suggested that the effect was fungistatic. Conidial germination of the commercially important obligate pathogen Sphaerotheca fuliginea (powdery mildew) was reduced to 11{\%}. The results show that neem. seed extracts possess antimicrobial activity with notable effects on some fungal phytopathogens. This work demonstrates that neem seed extracts have potential for controlling both microbial and insect pests.",
    keywords = "neem, antibacterial, antifungal, biochromatogram, phytopathogens, azadirachtin, PERFORMANCE LIQUID-CHROMATOGRAPHY, SEEDS, TREE, OIL",
    author = "E. Coventry and Allan, {Eunice Jessie}",
    year = "2001",
    language = "English",
    volume = "29",
    pages = "441--450",
    journal = "Phytoparasitica",
    issn = "0334-2123",
    publisher = "Springer Netherlands",
    number = "5",

    }

    TY - JOUR

    T1 - Microbiological and chemical analysis of neem (Azadirachta indica A. Juss) extracts: new data on antimicrobial activity

    AU - Coventry, E.

    AU - Allan, Eunice Jessie

    PY - 2001

    Y1 - 2001

    N2 - The antimicrobial effects of extracts of neem seed (Azadirachta indica A. Juss.) were investigated using microbial growth inhibition assays. A laboratory-prepared neem. seed extract along with a commercially available formulated product, were characterized using HPLC, and shown to be effective against a range of bacteria in an agar diffusion assay. The active ingredient, i.e., the unformulated seed extract of the commercial product, also showed activity and this was further investigated in a biochromatogram, using the sensitive bacterium Bacillus mycoides. Results showed antibacterial activity as three discrete inhibition zones that did not correspond to the R-f of the major neem. metabolites, azadirachtin, nimbin and salannin. This suggests that these compounds were not antibacterial. The colony radial growth rates of the fungal pathogens that cause 'take-all' and 'snow mould' disease were both significantly affected when the commercial, unformulated, neem seed extract was incorporated into the growth medium. Experiments in liquid culture suggested that the effect was fungistatic. Conidial germination of the commercially important obligate pathogen Sphaerotheca fuliginea (powdery mildew) was reduced to 11%. The results show that neem. seed extracts possess antimicrobial activity with notable effects on some fungal phytopathogens. This work demonstrates that neem seed extracts have potential for controlling both microbial and insect pests.

    AB - The antimicrobial effects of extracts of neem seed (Azadirachta indica A. Juss.) were investigated using microbial growth inhibition assays. A laboratory-prepared neem. seed extract along with a commercially available formulated product, were characterized using HPLC, and shown to be effective against a range of bacteria in an agar diffusion assay. The active ingredient, i.e., the unformulated seed extract of the commercial product, also showed activity and this was further investigated in a biochromatogram, using the sensitive bacterium Bacillus mycoides. Results showed antibacterial activity as three discrete inhibition zones that did not correspond to the R-f of the major neem. metabolites, azadirachtin, nimbin and salannin. This suggests that these compounds were not antibacterial. The colony radial growth rates of the fungal pathogens that cause 'take-all' and 'snow mould' disease were both significantly affected when the commercial, unformulated, neem seed extract was incorporated into the growth medium. Experiments in liquid culture suggested that the effect was fungistatic. Conidial germination of the commercially important obligate pathogen Sphaerotheca fuliginea (powdery mildew) was reduced to 11%. The results show that neem. seed extracts possess antimicrobial activity with notable effects on some fungal phytopathogens. This work demonstrates that neem seed extracts have potential for controlling both microbial and insect pests.

    KW - neem

    KW - antibacterial

    KW - antifungal

    KW - biochromatogram

    KW - phytopathogens

    KW - azadirachtin

    KW - PERFORMANCE LIQUID-CHROMATOGRAPHY

    KW - SEEDS

    KW - TREE

    KW - OIL

    M3 - Article

    VL - 29

    SP - 441

    EP - 450

    JO - Phytoparasitica

    JF - Phytoparasitica

    SN - 0334-2123

    IS - 5

    ER -