Vibrio harveyi

Antibacterial activity of the sea cucumber extracts were tested against five Gram-positive/negative bacterial strains: Staphylococcus aureus (ATCC 25923), Micrococcus luteus (ATCC 9341), Escherichia coli (ATCC 25922), Klebsiella pneumoniae (ATCC 10031) and Vibrio harveyi (ATCC 14126); which were obtained from the Pasteur Institute, Tehran, Iran.
Antibacterial screening was done by disc diffusion method (Vanden Berghe and Vlietinck 1991 ). For stock solutions, 10 mg of each extract of S.herrmanni were dissolved in 1 mL of DMSO. Mueller–Hinton Agar plates were inoculated with an overnight culture (12–16 h) of each bacterial strain. Whatman paper disks were placed on the agar surface and injected with 10 μL of each stock solution extract. Disks injected with DMSO were used as solvent control. Disks with standard antibacterial agent ampicillin (at 10 µg/disc) were used as positive control. After the 24 h-long incubation at 37 °C, The diameter of the inhibition zone (IZ) of bacterial growth was measured. No inhibitory effects due to the solvent were observed. The assays were repeated in triplicate.

The antimicrobial activity of the freeze-dried fruit tissue was tested on the following strains of microorganisms: (1) Gram positive bacteria Staphylococcus aureus (ATCC 9538), Bacillus subtilis (ATCC 6633), Enterococcus hirae (ATCC 10542), and Enterococcus faecalis (ATCC 29212); (2) Gram negative bacteria Escherichia coli (ATCC 10536), Pseudomonas aeruginosa (ATCC 15442), Vibrio harveyi (ATCC 12126), and Proteus mirabilis (ATCC 2011); and (3) yeast Candida albicans (ATCC 10231). All microorganisms were obtained from the culture collection of the Department of Biotechnology and Food Microbiology (Wrocław). The bacteria were grown in nutrient broth medium at 37 °C, except B. subtilis (ATCC 6633) which was grown at 30 °C. The yeast was grown in Yeast Extract Peptone Glucose (YPD) medium at 30 °C. The agar was added to the medium at a concentration of 2% when it was needed.

The antimicrobial activity of flours from oilseed cakes was determined for the following microorganism strains: (1) Gram-positive bacteria (G+) Staphylococcus aureus (ATCC 9538), Bacillus subtilis (ATCC 6633), Enterococcus faecalis (ATCC 29212) and Enterococcus hirae (ATCC 10542); (2) Gram-negative bacteria (G−) Escherichia coli (ATCC 10536), Vibrio harveyi (ATCC 12126) and Pseudomonas aeruginosa (ATCC 15442); and (3) the yeast Candida albicans (ATCC 10231). All microorganisms were obtained from the culture collection of the Department of Biotechnology and Food Microbiology (WUELS, Wrocław). Bacteria were grown in Luria broth (Sigma, Germany; containing 10 g/L tryptone, 5 g/L yeast extract and 5 g/L NaCl) at 37 °C; yeast was grown in YPD broth (Sigma, Germany; containing 20 g/L bacteriological peptone, 10 g/L yeast extract and 20 g/L glucose) at 30 °C. Agar was added to the medium at a concentration of 2% when necessary. To prepare an inoculation culture for the agar diffusion method, the cultures were grown in a 0.1 L flask containing 10 mL of proper medium, on a rotary shaker at 37 or 30 °C at 180 rpm for 48 h. Cells were washed in saline solution and adjusted to OD600 = 1.