Microbiological Quality of Blended Garlic Sold in Ado Ekiti

ABSTRACT
The microbiological quality of blended garlic obtained in Ado-Ekiti was assessed by analyzing
bacterial counts, morphological characteristics, and antimicrobial susceptibility patterns of
isolated strains. Bacterial enumeration revealed significant variations, with colony-forming units
per milliliter (CFU/mL) ranging from 2.0 × 10² to 2.5 × 10 , while some isolates exhibited an
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extremely high bacterial load (TNTC), preventing accurate counting. Certain isolates remained
below the countable limit (TFTC), suggesting the presence of both highly proliferative and less
dominant microbial populations. Morphological characterization of bacterial isolates
demonstrated diverse cultural and structural traits, with colony shapes varying from circular to
irregular, and coloration including creamy, yellow, blue-green, pink, and greyish-white. Bacterial
colonies displayed elevations ranging from flat to convex, with edges classified as entire,
undulated, or curled. Bacteria isolates include Bacillus substilis (14%), Staphylococcus aureus
(44%), Pseudomonas aeruginosa (12%), Salmonella spp (10%), Escherichia coli (18%), Listeria
monocytogene (2%). These findings indicate a heterogeneous microbial composition within
blended garlic. Antimicrobial susceptibility testing revealed a high prevalence of resistance to β-
lactam antibiotics, including Amoxicillin-Clavulanate (44%), Cefotaxime (52%) and Cefuroxime
(36%) indicating the widespread presence of cephalosporin-resistant strains. Resistance to
Cefoxime was also notable, reinforcing the potential for multidrug resistance among the isolates.
Variability in susceptibility patterns was observed for Ceftriaxone and Nalidixic Acid, with
isolates demonstrating complete resistance, intermediate susceptibility, or full susceptibility.
Resistance trends among carbapenems and fluoroquinolones were mixed, with Imipenem and
Ofloxacin exhibiting differing effectiveness across isolates. Nitrofurantoin and Gentamicin also
displayed inconsistent susceptibility profiles, suggesting varying resistance mechanisms among
the bacterial populations. Conclusively, this current study showed the microbial diversity in
blended garlic and the alarming resistance trends among isolates, raising concerns about
potential health risks associated with contaminated garlic products.
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