Abstract

Arikpo Ikpi Okoi, Nsor Odo Alobi, Magdalene Obi-Abang, Mike Omini Eko and Essien Archibong Okon

The bioactive and efficacy of ethanolic extracts of Zingiber officinale Rosc. and Gongronema latifolium Benth. were investigated in vitro on causative agents of post harvest decay of cassava. The phytochemical screening of the two plants were obtained by analysis of their extracts using established procedures. Results revealed high presence of saponins, cyanogenetic glycosides and polyphenols in Zingiber officinale, as well as anthraquinones in Gongronema latifolium, with moderate presence of flavonoids, alkaloids and cyanogenetic glycosides in the two plants, indicating their antifungal potentials. The pathogens isolated were Rhizopus stolonifer, Penicillium expansum, Fusarium moniliforme and Aspergillus niger. The fungi were cultured with the two plant extracts at concentrations of 100%, 80%, 60%, 40%, 20% and 10%, using potato dextrose agar (PDA). The antifungal activity increased with increase in concentration of the plant extracts. At 100% concentration, extract of Zingiber officinale showed the highest inhibition of mycelia growth in Aspergillus niger (97.37±1.56%) while that of Gongronema latifolium was 88.60±0.85%. Specifically, extracts of Zingiber officinale was more effective in inhibiting growth of the fungal isolates; and Aspergillus niger was found to be most sensitive to the extracts.