Phytochemical Screening, Mathematical Analysis and Antimicrobial Activity of Methanolic Seed Extract of Hunteria Umbellata

Aim: The study evaluates the in-vitro antimicrobial activity of Hunteria umbellata against Escherichia coli, Staphylococcus aureus and Streptococcus sp.

Place and Duration of Study: The study was carried out for three months in 2019 in Biochemistry Laboratory, Department of Chemical Sciences (Biochemistry unit), School of Pure and Applied Sciences, Lagos State Polytechnic, Ikorodu, Lagos- Nigeria.

Methodology: The qualitative and GC-MS analysis of Hunteria umbellata methanolic seed extract were determined using standard procedure. The antimicrobial activity was evaluated by the disc diffusion method and agar well diffusion method. The experimental data was resampled 1000 times to allow for higher degrees of freedom in carrying out t-test to test for the difference of the effect of in-vitro antimicrobial activity of H. umbellata against E. coli, S. aureus and Streptococcus sp using mathematical software R language (3.6.1 version). Line plots, histogram and t-test are used to explain the effect of antimicrobial activity of H. umbellate on the selected bacteria. MIC and MBC were determined using standard methods.

Results: The Phytochemical analysis of methanolic seed extract of Hunteria umbellata showed the presence of secondary metabolites like saponins, tannins, flavonoids, steroids, phenol among others. GC-MS assay of the H. umbellata seed extract revealed the presence of eight different compounds. Agar well diffusion method was characterized by inhibition zones of 18.36±0.87, 19.13±1.03 and 21.62±2.53 mm for E.coli, S. aureus and Streptococcus sp respectively at 300 mg/ml-1 and 21.70± 1.60, 23.83± 2.64 and 28.57± 1.52 for E.coli, S. aureus and Streptococcus sp respectively at 500 mg/ml. The results of the analysis show that there is a significant difference between the effects of in-vitro antimicrobial activity of H. umbellate on 3001 and 500 mg/ml on each bacteria tested at 5% level of significance. E.coli, S. aureus and Streptococcus sp were tested against 12 standard antimicrobial agents, of which six was sensitive and another six was resistance to E .coli, seven was sensitive, and five was resistance to S. aureus while four was resistance and eight sensitive to Streptococcus sp. The minimum inhibitory concentration (MIC) for E.coli, S. aureus, and Streptococcus sp were 250, 125 and 31.25 mgml-1 while their minimum bactericidal concentration (MBC) were 500, 250 and 125 respectively. MIC and MBC tests showed that H. umbellata methanolic seed extract had noticeable bactericidal effects with MBC/MIC values ranging between 2 to 4. The extract has strong potency against these microorganisms with Streptococcus sp being the most susceptible.

Conclusions: Hunteria umbellata has potential as natural therapeutic agents against E. coli, S. aureus and Streptococcus sp and they may prevent pathogenic diseases.