Phytochemical screening and in vitro antilisterial attributes of different aqueous and ethanolic leaf extracts
Keywords:
Antilisterial, Agar well diffusion, Aqueous extract, Ethanolic extract, Phytochemicals, RTE borne L. monocytogenesAbstract
Introduction. Listeria monocytogenes represents the Listeria species most commonly associated with disease in humans. The majority (99%) of the infections caused by L. monocytogenes are food-borne being ingestion of contaminated food especially contaminated ready-to-eat food products that do not undergo subsequent reheating. This organism has great economical implications in the food industry due to recalls of contaminated food products and temporary shutdown of many food processing plants. There has been lots of interest recently in the role of complementary and alternative medicines for the treatment of various acute and chronic diseases. The revival of interest in the use of African medicinal plants by many developing countries and the World Health Organization (WHO) has led to intensified efforts to explore the numerous plants with medicinal importance. A large number of phytochemicals belonging to several chemical classes have been shown to have inhibitory effects on all types of microorganisms in vitro. Knowledge of the chemical constituents of plants and their anti-Listeria ability is desirable because such information will be value for synthesis of complex chemical substances. The aim of this work was to study the phytochemical qualitative profiles and in vitro antilisterial attributes of aqueous and ethanolic leaf extracts from several plants against earlier documented Ready To Eat (RTE) associated multi antibiotic resistant L. monocytogenes strains. Materials and Methods. The examined aqueous and ethanolic leaf extracts were derived from Psidium guajava (guava), Zingiber officinale (Ginger), Dacryodes edulis (African pear), Citrus aurantifolia (Lime), Funtumia elastica (silkrubber), Vernonia amygdalina (Bitter leaf), Cassia alata and Moringa oleifera (horseradish tree). The respective L. monocytogenes strains utilized were; LMSN 70, LMEW 94 and LMMP 104. Invitro assay of aqeous and ethanol estracts of plants was assayed by agar well diffusion assay. Results and discussion. Alkaloids, saponins, steroids, terpenoids, cardiac glycoside, reducing sugar, phenolics, resins, flavonoids, and tannins were detected in Z. officinale ethanolic leaf extract whilst cardiac glycoside was absent in ethanolic leaf extracts of D. edulis, C. aurantifolia and F. elastica. Alkaloids, saponins, steroids, terpenoids, cardiac glycoside, reducing sugar, phenolics, resins, flavonoids, and tannins were detected in crude aqueous leaf extracts of Z. officinale and M. oleifera.F. elastica ethanolic leaf extract displayed the highest antilisterial potential at the least concentration; 100mg/ml whilst amongst the aqueous extracts, V. amygdalina leaf extract exhibited maximal antilisterial activities comparable with antilisterial inhibitory growth zones elicited by the respective ethanolic extracts with the exception of M. oleifera extracts.
Conclusion. Further studies aimed at the fractionation of the respective crude extracts especially F. elastica and exposing the respective multi antibiotic resistant food borne L. monocytogenes strains to these fractionated leaf extracts should be conducted.
References
Sharma AK, Gangwar M, Tilak R [et al]. Comaparative in vitro antimalarial and phytochemical evaluation of methanolic extract of root, stem and leaf of Jatropha curcas Linn. Intern. J. Pharm. Sci. Res 2012. Vol. 3. N0 6. P. 154-1553
Cowan MM. Plant products as antimicrobial agents. Clin. Mic. Rev 1999. Vol. 12. No 4. P. 564-582
Hao YY, Brackett RE, Doyle MP. Inhibition of Listeria monocytogenes and Aeromonas hydrophila by plant extracts in refrigerated cooked beef. J. Food Pro1998. Vol 61. No.3. P 307–312.
Ward T J, Gorski L, Borucki MK. [et al]. Intraspecific phylogeny and lineage group identification based on the prfA virulence gene cluster of Listeria monocytogenes. J. Bac 2004. Vol 186. P 4994–5002.
Lis-Balchin M, Deans SG. Bioactivity of selected plant essential oils against Listeria monocytogenes. Mic1997. V 82 No 6. P. 759–762.
Kim JM, Marshall MR, Wei C. Antibacterial activity of some essential oil components against five foodborne pathogens. J.of Agr F. Chem1995. V 43. No11. P.2839–2845.
Bakr RO, Omer EA, EL-Razik KAA. [et al]. Antioxidant and anti-listerial activities of selected Egyptian medicinal plants. Afr. J. Mic. Res 2013 V 7. No.37. P 4590-4595.
Blanco MM, Costa CARA, Freire AO. [et al]. Neurobehavioral effect of essential oil of Cymbopogon citratus in mice. Phyto. 2009. V 16. P 265–270.
Larson AE, Yu, RRY, Lee OA. [et al]. Antimicrobial activity of hop extracts against Listeria monocytogenes in media and in food. Intern. J. Mic1996. V 33 No. 3. P 195–207
Daniel OE, Onilude AA, Obayagbona O N. Prevalence of antibiotic resistant Listeria monocytogenes strains in Nigerian Ready-to eat foods. FS 2018. V. 6 No.3. P.118–125.
Harborne JB. Phytochemical methods. London Chapman and Hall, Ltd. 1973 P. 49-188.
Trease G, Evans C. A Textbook of Pharmacognosy. Twelfth edit. London: ELBS. 1985. P. 121
Obadoni BO, Ochuko PO. Phytochemical studies and comparative efficacy of the crude extracts of some homostaticplants in Edo and Delta states of Nigeria. Glo. J. P. App. Sci. 2018. V. 5. P 203-208.
Azu N, Onyeagba R. Antimicrobial Properties of extracts of Allium cepa (Onions)and Zingiber officinale (Ginger)on Escherichia coli, Salmonella typhi and Bacillus subtilis. Intern. J.Tro.Med.2006 V. 3 No. 2 P. 1-7
Asowata I, Erhabor OJ, Idu M. [et al]. Preliminary antimicrobial and phytochemical study of theaqueous,alcoholic and chloroform extracts of the leaves of Napoleonaea vogelli hook. and planch. (Lecythidiaceae). J.M.B.F.S 2013 V. 2 No. 4. P. 2279- 2292.
Adeshina GO, Jibo SD, Agu VE. Antibacterial susceptibility pattern of pathogenic bacteria isolates from vegetable salad sold in restaurants in Zaria, Nigeria. J. Mic. Res. 2012 V. 2 P. 5-11.
Gull IM, Saeed M, Shaukat H. [et al]. Inhibitory effect of Allium sativum and Zingiber oficinale extracts on clinically important drug resistant pathogenic bacteria. Ann.Clin. Mic. Antimic 2012 V. 11. P. 8-10.
Omoya FO, Akharaiyi FC. Mixture of honey and ginger extract for antibacterial assessment on some clinical isolates. Intern. Res. J. Pharma 2012 V. 2 P. 127-132.
Omoregie EH, Ibrahim I, Ibekwe N. [et al]. Broad spectrum antimicrobial activity of Psidium guajava linn leaf. Nat. Sci2010. V. 8. No. 12. P. 43-50
Nwokonkwo DC. The phytochemical study and antibacterial activities of the seed extract of Dacryodes edulis (African Native Pear). Amer. J. Sci. Ind. Res 2014 V.5. No.1. P.7-12
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