Mineral Composition and Presence of Escherichia coli in Selected Vended Sachet Yoghurts in Obio/ Akpor, Rivers State, Nigeria

Aims: Sachet yoghurts as one of the ready-to-eat foods commonly available in the market mainly for pupils need to be microbiologically safe for consumption. The study was aimed at ascertaining the safety of retailed sachet yoghurt vended in Obio/Akpor in Rivers State, Nigeria.

Study Design: This work is based on completely randomized design with two replications and the average values calculated.

Place and Duration of Study: Emmadavistic Laboratory, Osak’s house, East-West Road, Port Harcourt, between June and November 2022.

Methodology: A total fifty (50) samples from 10 brands (A-J) were examined for the presence of Escherichia coli (E. coli), their sensitivity to common antibiotics and possession of virulence genes [E. coli attaching and effucing (eaeA), aggregative adherence fimbriae (aggR) and antimicrobial sensitivity testing (astA)] using Eosin methylene blue agar. Mueller Hinton agar and virulent gene primer.

Results: The results of the total heterotrophic plate count revealed range of 4.8×105 to 1.47 × 106 cfu/ml. The count of E. coli ranged from 4.4 to 7.5 × 102 cfu/ml from D and I products, respectively. The results of mineral content revealed the presence of magnesium (202.1 – 314 mg/100 g), calcium (117.81 to 176.31 mg/100g), potassium (30.14 to 48.62 mg/100g), phosphorus (8.62 to 12.91 mg/100g). The confirmed E. coli showed varying resistance to augmentin (70%), gentamicin (0%), cefuroxime (100%), cefixime (100%), ofloxacin (0%), nitrofurantoin (20%), ciprofloxacin (0%) and ceftazidime (100%). None of the confirmed Escherichia coli produced the expected bands of 106,248 and 254 base pair against eaeA, astA and aggR, respectively.

Conclusion: The presence of antibiotics resistant Escherichia coli in two samples portends danger for the consumers and is indicative of poor water treatment.