Some tissues of the body such as the amniotic membrane and cheap and available medicinal plants such as Arnebia euchroma can be effective in treating burn wounds, reducing its infection, and healing time. The aim of the present study was to investigate the antimicrobial effects of a combination of amniotic membrane, Arnebia Euchroma (AE) extract, sesame oil, and bee wax on the growth of gram-positive and gram-negative bacteria in second-degree burn wounds. After receiving amniotic membrane tissue from pregnant women, this tissue was mixed with sesame oil, bee wax, and Arnebia Euchroma extract and applied to the burn wounds of mice model infected with E. coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii. This combination was applied in case and control groups, and microbial counting was then performed. According to the findings of the present study, the number of pathogens in wound samples of mice treated with this combination was less than in control mice. The results of this study also showed that the use of a combination of amniotic membrane, AE plant extract, sesame oil, and bee wax had a therapeutic effect on second-degree burn wounds. The use of this compound after further research is recommended for the treatment of burn wounds.
Introduction: Tyrosine oxidizing enzymes or tyrosinases have various applications in medicine, nutritional, and environmental disciplines. By considering actinobacteria’s impacts as one of the most promising bacteria in producing bioactive compounds and valuable enzymes with medical, industrial, and environmental applications, the current study was performed to screen and identify tyrosinase-producing isolates soil samples of the Maranjab Desert, the Hampoeil cave, and the Hormoz Island. Materials and Methods: In this research, the soil samples collected from the Maranjab Desert (10 samples) and Hormuz Island (10 samples) were cultured in ISP2 agar, and the actinobacterial colonies were isolated. The isolates and the previously-isolated strains from the Hampoeil cave were qualitatively screened by culturing on tyrosine agar medium. The result of primary screening was confirmed by culturing in tyrosine broth. Then, the tyrosinase activity of the selected isolates was quantitatively evaluated. Finally, these isolates were identified by sequencing and analyzing the 16S rRNA gene. Results: Among the 89 screened actinobacteria, 17 colonies showed clear zone and brown-black pigmentation around their colonies on tyrosine agar and were subjected to secondary qualitative screening. The results of secondary screening confirmed that 11 isolates produced tyrosinase. Also, the quantitative test results revealed that the strains designated UTMC 3165 and UTMC 3233 had the most enzyme activity, as 33 and 35 unit/ml, respectively. In the molecular identification, the isolates showed 99.67% and 99.88% similarity to Streptomyces tendae and Streptomyces thermocarboxydus, respectively. Discussion and Conclusion: The results of the present study showed that the soils in Iran possess promising actinobacteria with the ability to produce tyrosinase enzymes. These strains were the members of the Streptomyces genus.
Introduction: Due to the increasing trend of industrial development and also the industrial production, the presence of heavy metals along with industrial wastewater is undeniable. Despite the various ways to remove heavy metals, choosing biological methods can be the best way to control them. Using bacteria in this field can be very useful and inexpensive with less harm. Materials and Methods: In the present study, various aquatic environments including rivers, ponds, industrial effluents, and activated sludge were sampled. Bacteria were identified based on the growth in iron-specific culture medium in terms of shape and 16S rRNA gene. These bacteria were cultured in specific culture media for iron-oxidizing bacteria, Luria-Bertoni (LB) and PHG II, containing 2 ppm of mercury chloride and cadmium chloride. The samples were then examined for the reduction or non-change of mercury and cadmium concentrations by atomic absorption spectrometry. Results: The results of the present study showed that the isolated bacteria were rod-shaped and chemoorganotrophic belonging to the genus Bacillus. The average percentages of mercury and cadmium removal by the isolated bacteria were about 95% and 40%, respectively. The highest percentage of the removal of both heavy metals was observed in the effluent sample of iron factory wastewater. Discussion and Conclusion: Iron oxidizing bacteria were identified as reducing agents of heavy metals in the laboratory environment. These bacteria grew in both LB medium and iron-specific culture medium. The highest percentage of the removal of both heavy metals was observed in the effluent sample of the iron processing plant. Based on the results, it can be said that the bacteria of each environment have adapted to the compounds of that place and are the best option to remove compounds such as heavy metals.
AbstractIntroduction: Tolerance to ethanol is a key characteristic of the yeast Saccharomyces cerevisiae. Any increase in ethanol tolerance in the industrial strains could lead to faster and more complete fermentations, and may also allow the production of more alcohol. Due to the complex nature of ethanol tolerance, it appears that a large increase in ethanol tolerance requires several changes in the yeast’s genome. Several approaches that rely on the effect of (random) variation generated by evolutionary engineering or mutagenesis have successfully yielded strains with increased ethanol tolerance.Materials and Methods: In the present study, to improve the ethanol tolerance phenotype in the industrial Ethanol Red strain, the parent strain was mutated physically and chemically. The mutants were screened using 1-butanol containing medium. The primary parent and the mutants were evolved within 144 days with evolutionary engineering strategy, while ethanol production of the selected strains was investigatedResults: According to the increase in the maximum growth rate, 8 strains were selected including parental strain and mutants, and the amounts of ethanol production of these strains were evaluated after evolutionary adaptation tests. Ethanol production of ER 103 and ER 106 which were mutated with EMS before the adaptive evolution test and then evolved at 11 and 9% v/v ethanol was improved from 103.44 ± 0.5 g/L to 112.45 ± 1 and 112.3 ± 0.9 g/L, respectively.Discussion and Conclusion: Due to the extensive capabilities of the evolutionary engineering method in creating capable strains in order to increase ethanol tolerance in industrial strains, the evolutionary engineering strategy was used. To increase the genetic diversity of the primary population, before starting the adaptive evolution experiments, mutation with ethyl methane sulfonate was used, which was more efficient than ultraviolet radiation in accelerating the evolution process to achieve the desired phenotype.
AbstractIntroduction: Hydrogen gas has great potential as a renewable energy source. Although hydrogen gas is obtained from fossil fuels, there is a demand for its production by chemical methods and electrolysis of water, and its extraction from oil sands is currently being studied. Its biological production is one of the cleanest types of hydrogen fuel production due to the consumption of greenhouse gases such as carbon dioxide and/or aerobic and anaerobic fermentation of agricultural wastes, and it can be considered as a solution for simultaneous production of the fuel and elimination of environmental pollutions.Materials and Methods: The present study briefly explains the hydrogen-producing microorganisms, the mechanisms, and the effective enzymes in their production. For this purpose, authoritative articles published between 2006 and 2021 and information in the Scopus database have been used to draw graphs and write this review article. In addition, some limitations and the ways to overcome them for increasing biohydrogen production are described in detail.Results: The results show that carbon dioxide fixation, fermentation, nitrogen fixation, aerobic and anaerobic photosynthesis are some ways of biological production of this fuel.Discussion and Conclusion: Important elements in biological production are the effective enzymes in these reactions and the possibility of using these enzymes in the continuous production of gas, and the purification of hydrogen from other gases. The stabilization of these enzymes under their conditions is of particular importance for the mass production of this gas. Purification of bio-produced hydrogen gas is essential for consumption as fuel, and some technologies, including nanomembranes such as polysulfonate, are very helpful in purifying this gas from other gases such as oxygen, nitrogen, ammonium, hydrogen sulfide, and oxygen.
