جستجوی مقالات مرتبط با کلیدواژه "antibacterial activity" در نشریات گروه "شیلات"

Recently, the use of nanoliposome and coated systems has received much attention due to their unique properties for more effective delivery of antibacterial agents. The phenolic extract was co-encapsulated into nanoliposomes and a polyelectrolyte delivery system was obtained by the sequential deposition of positive chitosan (CH) and negative sodium alginate (AL) onto the surface of anionic nanoliposomes (NLs). Phlorotannin compounds were identified by HPLC and the properties of nanoliposomes were evaluated. Minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) of NLs/extracts against acne-related bacteria were determined. The identified compounds of the extract were phloroglucinol, bieckol, dieckol, phlorofucofuroeckol A, and eckol. The mean particle size, zeta potential, and polydispersity index of NLs were 19.77 nm, -13.3 mV, and 0.212, respectively. NLs efficiency on days 0 and 60, at 4°C, was 91.22 and 67.16%, respectively. Release of NLs at pH 3 was higher than at pH 5 and 7. The MIC and MBC values of NLs, AL-CH-NLs, and CH-NLs against all studied bacteria are lower than the extracts. The MIC and MBC activity of the nanoliposomes and coated nanoliposomes decreased over time. The results suggested that NLs, especially CH-NLs and AL-CH-NLs, can be considered an effective carrier system for phenolic compounds.

It is believed that the marine animals contain many compounds that could be beneficial for the treatment of many diseases. In this study, the acetone extract of Stichopus hermanni was fractionated by a liquid chromatography and then fractions were assayed for terpenoids. The fraction C18 that received a positive response for terpenoids was purified further and characterized by the liquid chromatography, mass spectral, and Thin-layer chromatography analysis. A terpenoid compound, squalene, was identified as the constituent of the bioactive extract fraction. Antimicrobial activity of C18-3 was tested against Bacillus subtilis, Bacillus cereus, Pseudomonas aeruginosa, Salmonella typhi, Proteus vulgaris, Escherichia coli, Klebsiella pneumonia, Staphylococcus aureus, and Nocardia brasiliensis pathogens. The lowest MIC and MBC values were observed in the Bacillus cereus (50 µg/mL) and Staphylococcus aureus (500 µg/mL), MIC and MFC the fungal pathogen Candida albicans (400 and 2000 μg/mL) and was cytotoxic against KB/ C152 and HUT-78/C185 cells (IC50 6.1 μg/mL and 6.29 μg/mL). This research suggests S. hermanni can be used as an alternative source for the separation and purification of squalene compound as a medicinal supplement.

Marines are unique resource that provides a diverse array of natural products, primarily from invertebrates such as sponge. As infectious diseases evolve and develop resistance to existing pharmaceuticals, these ecosystems provide novel leads against microbial, cancer, and viral diseases. The purpose of this study is to investigate antimicrobial and antifungal activities of derivatives of phthalates extracted from Haliclona (Soestella) caerulea on some pathogenic organisms. Sponge samples from Larak Island were collected by divers at a depth of 10 meters. After that, marine sponge extract collection was done by chloroform-methanol extraction as a solvent and through chromatography column and nuclear magnetic resonance (NMR) spectroscopy on the sponge sample, components of dioctyl phthalate (DOTP) and dibutyl phthalate (DBP) were purified and identified. Anti-microbial and antifungal activity of extracted components were investigated by means of bacterial broth dilution method and microdilution broth method and minimum inhibitor concentration (MIC), minimum bactericide concentration (MBC), and minimum fungal concentration (MFC) were determined. The results indicated that DOTP of H. (Soestella) caerulea was active on Bacillus subtilis, Bacillus cereus bacteria. MBC values of DOTP were determined as 2000 μg/m. DBP of H. (Soestella) caerulea was active on gram positive bacteria. MBC values of DOTP were determined as 1000 μg/m for B. cereus and Staphylococcus aureus and 500 μg/mL for B. subtilis. MFC values of DOTP and DBP were determined as 1000 μg/m and 2000 for Candida albicans. Hence it is assumed that the sponge Haliclona (Soestella) caerulea exhibited high antimicrobial activity.

Seaweed Gracilaria verrucosa is one of the potential marine natural resource commodities in Karawang Regency, Indonesia. Solid soap is one of the added value products that can be developed from seaweed since it has a potential antibacterial function for human skin. The solid soap with seaweed enrichment sale could increase the seaweed farmers and coastal community income. This study aims to produce solid soap with the addition of different seaweed G. verrucosa formulations and examine the sensory, physicochemical parameters, and antibacterial activity of the soap. This study applied five variants: solid soap with the addition of 0.025%, 0.050%, and 0.075% seaweed water extract (W250, W500, and W750), 0.075% seaweed ethanol extract (E750), and seaweed pulp (SWP). The variant W500 and SWP have the highest attributes according to the sensory (aroma, color, amount of foam, and power of detergency) and physicochemical (pH, foam stability, and unsaponifiable fat content) parameters, respectively. The variant SWP and W500 also have a strong antibacterial activity. From the results, the variant SWP and W500 can be the candidates for further product development.

Looking for effective alternatives, such as secondary microbial metabolites, is needed to restrict the use of antibiotics in farmed fish and their detrimental effects on public health and the environment. Thirty-three water and sediments samples were collected from coastal areas in the Basrah Governorate, southern Iraq, to assess their biological activity against bacterial pathogens isolated from Cyprinus carpio, with enteric red mouth disease. 20 spore-forming bacteria were isolated and identified by VITEK BCL cards and amplifying the gyrA gene. Furthermore, the secondary metabolites produced by the strains were extracted and analyzed by GC-MS. Four pathogenic bacteria were isolated from common carp infected with the enteric red mouth disease. The antibacterial activity of the extracts of the isolated marine strains was examined on bacteria causing enteric red mouth disease and Y. ruckeri and P. aeruginosa. Based on the results, the marine isolates were identified as B. spizizenii and GC-MS analysis revealed that these strains’ extract contained amino acids and their derivatives and esters and hydrocarbons. Also, biochemical identifications showed that the bacteria isolated from fish belonged to the species of Yersinia ruckeri, Aeromonas hydrophila, Streptococcus agalactiae, and Pseudomonas aeruginosa. According to the antibacterial activity assay, the extracts of B. spizizenii strains were considerably active against bacteria involved in enteric red mouth disease, especially Y. ruckeri. These findings indicate marine B. spizizenii can be replaced with antibiotics in the aquaculture industry to combat infections.

The antibacterial activity of oregano (Origanum vulgare) essential oil (OEO), carvacrol and thymol was tested against seven Gram-negative and nine Gram-positive fish pathogenic bacteria isolated from cultured olive flounder (Paralichthys olivaceus) in Korea. Disk diffusion assay, MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration) tests showed OEO, carvacrol and thymol inhibiting the growth of both Gram-negative and Gram-positive bacteria. Carvacrol and thymol showed lower MIC values than OEO against every isolate which ranged from 0.001 to 0.007 % (V/V) and 0.001 to 0.062 % (V/V), respectively. Carvacrol (MBC/MIC= 1-4) and thymol (MBC/MIC= 2-4) were bactericidal for all tested strains while OEO (MBC/MIC= 2-8) was being both bactericidal and bacteriostatic. In every fish pathogenic bacteria, the inhibition zone diameter (IZD) increased in proportion to the oil concentration and the maximum effect was found at 100 % (V/V) concentration of OEO, carvacrol and thymol. The antibiogram pattern indicated that all the bacterial strains excluding three strains of S. iniae (S186, S530, and S131) showed resistance to one or more antibiotics. The percentage of relative inhibition zone diameter (RIZD %) exhibited high values at higher concentration of all agents. Since antibacterial activities of OEO, carvacrol and thymol were considerably effective against fish pathogenic bacteria, their use could be alternatives to treat bacterial infections in aquaculture.

Fucoxanthin contents of four species of brown seaweeds (Dictyota indica, Padina tenuis, Colpomenia sinuosa and Iyengaria stellata) from intertidal zone of Qeshm Island, Persian Gulf were assessed in summer and winter of 2016. In addition, some physicochemical properties (pH, temperature, salinity and conductivity) of seawater were monitored on the same time. The antibacterial activity of algal extracts was determined by disc diffusion assay, minimum inhibitory and minimum bactericidal concentration tests; and the antioxidant activity through ferric reducing antioxidant power method. The fucoxanthin contents of the studied seaweeds were higher in winter. D. indica showed the highest amount of fucoxanthin (approximately 462.79 and 210.72 µg/g) in both seasons, which makes it commercially applicable e.g. in food and pharmaceutical industries. Furthermore, D. indica, I. stellata, P. tenuis and C. sinuosa showed a strong ferric reduction power in both seasons. Considerable inhibition zone against gram negative (Escherichia Coli: PTCC1330) and gram positive bacteria (Staphylococcus aureus: PTCC1112) were also observed.