LOGARITHMIC AND PERCENTAGE REDUCTIONS OF BACTERIAL ISOLATES IN GALATEA PARADOXA TREATED WITH CITRUS AURANTIFOLIA AND NACL: PUBLIC HEALTH IMPLICATION AND NUTRITIONAL ASSESSMENT

Shell fishes constitute a vital source of food for humans due to its high nutritional values. Bacteriological and nutritional assessments of Galatea paradoxa treated with Citrus aurantifolia and NaCl were determined using bacteriological and analytical protocols. The results revealed a reduction from 4.845 to 2.301 Log CFU/g in Total Heterotrophic Bacterial Counts (THBC) in G. paradoxa treated with 10% NaCl for 5 mins. The G. paradoxa treated with 7.5 % NaCl for 5 min had a reduction in Total Coliform Counts (TCC) ranging from 3.903 to 2.398 Log CFU/g, while Total Faecal Coliform Counts (TFC) in G. paradoxa treated with 5 % and 10 % for 10 min reduced by 99.99 %. There was 53.46% THBC reduction in G. paradoxa treated with 10% C. aurantifolia for 5 min; THBC in G. paradoxa treated with 10% C. aurantifolia for 10 min reduced by 79.36 %; THBC in G. paradoxa treated with 10 % equal concentrations of NaCl and C. aurantifolia decreased by 99.99 % within 10 min, while TCC in G. paradoxa treated with 7.5 % equal concentrations of NaCl and C. aurantifolia within 10 min of exposure had 99.99 % decrease. The predominant survived bacterial genera in treated samples were Bacillus, Vibrio and Micrococcus. There was insignificant difference (p ≥ 0.05) between the nutritional compositions of treated and untreated samples. This study showed that G. paradoxa could be treated with C. aurantifolia and NaCl so as to avert possible foodborne diseases associated with consumption of this aquatic food.

Bacterial Isolates from Bivalve Clams (Galatea paradoxa, Born 1778): Occurence, Multi-drug Resistance, Location of Antibiotic Resistance Marker and Plasmid Profiles

The occurrence of bacterial isolates in Galatea paradoxa (Born 1778) was determined using standard bacteriological method. The multi-drug resistance, location of antibiotic markers, plasmid DNA extraction and electrophoresis was determined by disc diffusion, acridine orange, TENS alkaline lysis and 0.8% agarose gel electrophoresis, respectively. Of the 63 bacterial isolates from G. paradoxa, Staphylococcus aureus and Streptococcus pyogenes had the highest and lowest percentage of occurrence with 40.0% and 5.0%, respectively. Escherichia coli was 25.0%, Pseudomonas aeruginosa (17.5%), Enterococcus spp and Salmonella spp (15.0%) each, Bacillus subtilis (12.5%), Klebsiella pneumoniae and Enterococcus faecalis (10.0%) each while Vibrio cholerae was (7.5%). The results showed Streptomycin and Ciprofloxacin as the most effective antibiotics against bacterial isolates from G. paradoxa. Bacillus subtilis and P. aeruginosa displayed 100% sensitivity to Streptomycin; Salmonella spp and E. faecalis were 100% sensitive to Augmentin. V. cholerae and S. pyogenes showed 100% resistance to Penicillin and Rifampicin, respectively. Of the 63 bacterial isolates, 43 (68.3%) were multidrug resistant (MDR) isolates, of which S. aureus and E. coli had the widest multiple antibiotic resistance (MAR) indices ranging from 0.3 to 0.8, while S. pyogenes had the least MAR ≤ 0.5. Of the 43 MDR bacterial isolates, 16.3%, 23.3% and 60.5% had their entire antibiotic resistance encoded on plasmid, chromosome and both plasmid and chromosome, respectively. The agarose gel electrophoresis showed that MDR bacterial isolates from G. paradoxa had plasmid DNA with molecular weights ranging from 23.1 to 31.5kb. This study has showed that G. paradoxa harboured bacteria which could pose serious health risks and G. paradoxa should be adequately cooked before consumption.

Shell Growth Pattern and Percentage Flesh Yield of the West African Clam, Galatea paradoxa (Born, 1778) from Itu Creek, Niger Delta Nigeria

Shell Morphometry is a fundamental tool for the evaluation of phenotypic stocks. The shell growth pattern and percentage flesh yield of Galatea paradoxa from Itu Creek in Niger Delta were investigated using standard morphometric methods. The mean in centimeter (cm) of 9.71±0.09, 35.02±0.22, 23.21±0.12, 37.11±0.25, 29.31±0.16 and 7.32±0.04 were recorded for shell length, maximum width, maximum height, nacre length, nacre width and hinge length respectively. Mean live weight of 115.70±1.09 g, mean flesh weight of 37.91 ± 0.23g and mean shell weight of 66.82±0.97 g were recorded for this species. Galatea paradoxa showed negative allometric growth (b < 3) while the correlation coefficients (r) in all the shell variables were far below „1‟, indicating a week correlation between the parameters. About 19% of the live weight of the clam is made up of flesh by weight. Keywords: Bivalve, Clam, Shell dimension, Niger Delta.