جستجوی مقالات مرتبط با کلیدواژه « بیوسورفکتانت » در نشریات گروه « شیمی »

There is a lot of evidence about the beneficial biological effects of probiotics in food and dairy products. Antimicrobial properties, ability to produce biosurfactant and biosynthesis of nanoparticles are among the significant effects of these organisms. The aim of this research is the biosynthesis of magnesium oxide nanoparticles by Enterococcus hirai from traditional yogurt. MRS agar culture medium was used to isolate probiotics. Biosurfactant-producing isolates were examined in terms of hemolysis, crude Oil Spreading Assay, Drop Collapse Assay and emulsification index, the best isolate for the production of magnesium oxide nanoparticles, size, antioxidant activity, FTIR and antibacterial effects were evaluated and identified by PCR. 9 isolates had probiotic properties, isolate L11 was selected with higher biosurfactant production ability. The antibacterial property of the produced biosurfactant was shown against Gram-positive and Gram-negative bacteria. This strain was also able to produce magnesium oxide nanoparticles. The formed nanoparticles with a size of 135 nm showed significant antibacterial and antioxidant effects. The best strain was introduced as Enterococcus hirai. According to the findings, it seems that this probiotic strain producing biosurfactant and magnesium oxide nanoparticles can be used in food and industrial industries.

The use of chemical surfactants such as sodium lauryl sulfate in detergents can cause various problems such as skin and eye irritation, nervous system disorders and cancer. Therefore, the use of biosurfactants due to their low toxicity and biodegradability has received much attention. In this study, the production of a green shampoo sample using rhamnolipid biosurfactant was investigated. First rhamnolipid bio-surfactant was produced from Pseudomonas arginosa PTCC 1340 with using of soybean oil as a carbon source in a laboratory scale of about 1.4 g/L and proved by thin-layer chromatography (TLC) analysis and Fourier transform infrared spectroscopy (FTIR). The results of the retardation factors in TLC paper showed that a rhamnolipid mixture (type 1 and 3) was produced. The appearance, chemical and microbial properties of green shampoos were investigated by replacing produced rhamnolipids with sodium lauryl sulfate. By comparing the results with standard reference values, it was found that the properties of the green shampoo samples were in the standard range based on the formulation presented in this study. These results can be a step toward improving the quality of lifestyle of people's life in the community.

Surfactants have received much attention as amphipathic compounds due to their widespread use. The production of surfactants by microorganisms (biosurfactants) has advantages such as toxicity less than chemical methods. Due to its antimicrobial and anti-biofilm properties, the use of biosurfactants in food preservation can be very valuable. In this study, a review, as well as a bibliometric analysis of the use of biosurfactants in food storage, has been performed. Documents were collected from the Scopus database and then analyzed using VOSviewer software. Examining the documents, it was found that only 15 documents have been published in this regard. The share of immunology and microbiology is higher than other fields, and India has published the most documents in this database with 6 documents. The small number of documents and the lack of documents such as conference papers and book chapters can indicate the lack of research done despite the great importance of the subject matter.

In this study, the micellization behavior of the sodium cholate (SCH) and sodium dodecyl sulfate (SDS), in aqueous solution in pure state, and mixture of them (SCH + SDS) in different mole fractions were investigated by conductometric method at 298.15 K. The obtained data from experimental measurements were used to determination of the critical micelle concentration (CMC) of surfactants in pure and mixed state. Also according to Regular Solution Theory (RST), were calculated the following parameters: the interaction parameter between surfactants in the mixed system (), activity coefficient (،), mole fractions of the components in the mixed micelle (,) and thermodynamic parameters such as Gibbs free energy of micellization () and excess free energy (). The results obtained show that in the anionic-anionic mixture, the interaction parameter is low and the activity coefficients show a small deviation from the ideal state, the standard Gibbs free energy of micellization () are negative values, this shows that the micelle formation process take place spontaneously.

In this research, biosurfactant production (surfactin) by Bacillus subtilis NLIM 0110 has been investigated. This microorganism was isolated from agricultural area of Iran. For surfactin production, the best condition of biosurfactant in shake flask was obtained at 37°C and 250 rpm. In this condition, maximum production of biomass and biosurfactant are 4 and 1.8 g/L. The yield of biosurfactant on biomass (Yp/x), biosurfactant on sucrose (Yp/s), and the volumetric production rate (Y) for shake flask were obtained about 0.45 g/g, 0.18 g/g, and 0.03 g/L.h, respectively. For this microorganism, the production of biosurfactant was proportional to the cell growth representing biosurfactant as a growth-associated product. The produced surfactin showed good surface activity because it is able to reduce the surface tension from 72 mN/m to 25 mN/m. Therefore, the proposed biosurfactant is appropriate candidate for industrial applications.