Assessment of the Bacteriological Quality of Some Fish Products

Abstract

F ISH products are considered a nutritionally significant component of the human diet because they contain macronutrients (proteins, fats, and ash) and micronutrients (vitamins and minerals). Accordingly, 200 different commercial fish product samples (25 each of canned solid tuna, canned chunks tuna, canned crumbled tuna, canned anchovy, canned mackerel, canned sardine, herring, and tilapia fillets) of different brands were collected from various local and high supermarkets in Aswan City during 2020-2021. The samples were subjected to microbial quality assessment, and PCR was carried out to detect some virulence genes of fish-borne pathogens to evaluate the control measures for food safety. The results presented that the highest bacterial loads (cfu/g) in the examined fish products were proven in fillets tilapia (1.3×104±0.32) and herring (1.0×104±1.2) while anchovy, mackerel, and crumbled tuna were the highest anaerobic count with means of 7.3×103±1.2, 7×103±1.6 and 6.7×103±1.4, respectively. The prevalence of P. aeruginosa occurs with an incidence of 29%. The lasB gene (50%) has been the most detected virulence gene, followed by exoS (40%). V. parahaemolyticus was present in 7.5%, and the regulator toxin genes (toxR and L.tdh) were found in 33.3% and 22.2%. Additionally, 20% of the samples had A. hydrophila, and the aerA and act genes were found in 60% of the isolates. In addition, C. perfringens was detected in 33% of examined products, and the virulence genes cpa and etx were present and discovered to be a proportion of 20% and 50%, respectively. The current study concluded that the examined fish products possess one or more food poisoning virulence genes indicating unsanitary handling, transport, processing, storage practices, and inappropriate environmental conditions.

Bacterial Quality and Molecular Detection of Food Poisoning Virulence Genes Isolated from Nasser Lake Fish, Aswan, Egypt

“…On the other hand, A. hydrophila virulence-associated genes ( aerA and Act ) were found in 60% and 40% of the inspected A. hydrophila isolates ( Figure 3 ). These results matched Emeish et al [ 58 ] and Elbarbary et al [ 59 ], who recorded 64.3% and 60% of the inspected A. hydrophila isolates. The results were lower than those of Ahangarzadeh et al [ 60 ], who detected aerA and act genes in 51.61% and 74.19%, respectively.…”

“…The findings of this study revealed lower incidence rates of rpoB and lasB genes in P. aeruginosa isolates compared to the analysis shown by Benie et al [ 64 ], who detected rpoB and lasB I with incidences of 91.1% and 89.2%, respectively. Meanwhile, the current results were higher than those reported by Elbarbary et al [ 59 ] and Shahrokhi et al [ 70 ], who confirmed that the lasB gene (50%) had been the primary detected virulence gene in inspected P. aeruginosa isolates. These results indicate that some virulence factors assist bacterial establishment and colonisation on the surface of the host, while others expedite the invasion of numerous tissues.…”

“…These recordings corresponded with the data from Abd El-Maogoud et al [ 66 ], who noted similar frequencies (47.3%). A previous study by Mamdouh et al et al [ 39 ] confirmed higher occurrences (65.0%) of P. aeruginosa in the examined samples, while Ali et al [ 38 ], Elbarbary et al [ 59 ], and Abd El-Maogoud et al [ 66 ] recorded lower incidences of 13.8%, 5.0%, and 29%. Pseudomonas is a part of the usual fish microflora and can be opportunistic and developed into virulent and disseminated in distressed fish [ 67 ].…”

“…Similar outcomes obtained by Ahmed et al [ 73 ] recorded 15.1%. High outcomes were achieved by Asran et al [ 31 ] and Morshdy et al [ 74 ], who identified V. parahaemolyticus in 50% and 42.3% of inspected fish; meanwhile, Elbarbary et al [ 59 ], Suresh et al [ 75 ], and Yen et al [ 76 ] reported low percentages of 2.3%, 3.89%, and 7.5%. A statistically significant difference was found between fish samples and the incidence of V. parahaemolyticus ( p < 0.05).…”