Advanced Research in Microbial Metabolite and Technology
Volume:5 Issue: 1, Winter-Spring 2022

In recent decades, effective herbal and natural compounds have been formulated with topical application, reduced side effects, and more economic benefits for Cutaneous Leishmaniasis (CL) treatment. Some of these include Propolis, Royal jelly, Ostrich oil, and Aloe Vera, which have widespread use in health products. The study aimed to evaluate the potential therapeutic effects of a prepared topical combination, including Propolis, Royal jelly, Ostrich oil, and Aloe Vera, on Leishmania major lesions under an in vivo model in BALB/c (concatenation of Bagg and Albino) mice. Fifty BALB/c mice were randomly divided into five groups of ten. CL lesions were induced by inoculation of metacyclic promastigotes at the base of the BALB/c mice's tails. The resulting lesions were treated topically with prepared natural combinations of Propolis, Royal jelly, Ostrich oil, and Aloe Vera. The lesion sizes were determined as the mean ± standard deviation. One-way analysis of variance (ANOVA) with the Bonferroni correction method was used for statistical analysis, with p < 0.05 considered statistically significant. Based on the data of this research, comparative ulcer size reductions were 63.4% (3.25 mm ± 0.24), 68.4% (3.55 mm ± 0.22), and 8.5% (0.44 mm ± 0.98) for the natural combination treatment 1, treatment 2, and Glucantime, respectively. Based on the results, the proposed natural combinations were significantly more effective at reducing ulcer size than Glucantime, the standard drug (p<0.05). Collectively, we conclude that a combination consisting of Propolis, Royal jelly, Aloe Vera, and ostrich oil is effective in treating CL in mice and may provide a new agent in the treatment of Leishmaniasis.

Enzymes, such as protease, occupy a pivotal position in the world of enzymes with respect to their applications in both physiological and commercial applications. Bacillus, like Bacillus licheniformis, produce protease and was used throughout the present study. The Bacillus licheniformis is a potential microorganism for producing proteins with various functions, including protease with substantial activity, effective pH, and temperature tolerance, at laboratory and industrial scales. This study investigated the effect of several temperatures ranging from 25-50 οC, pH ranging from 7-10.5, shaker speeds of 100-200, and inoculum concentrations of 3-12 %V/V on enzyme production. Results showed that cultivating the medium at about pH (8.5), a temperature of 35 οC, and a shaker gyratory speed of 180 rpm influenced protease production. Firstly, it was found that using yeast extract, soybean meal corn, and steep liquor (powder) as nitrogen sources also enhanced protease production. Furthermore, cornstarch and glucose of 3 %W/V were found to be effective as a carbon source for protease production. The protease stability was retained for almost 35 minutes, heating at 60 οC and pH 8.5, and as heating continued at the same temperature and pH, the enzyme had 40% of its activity. Secondly, the effect of different metal ions types on the stability of the partially purified protease is reported. It was found that the protease activity at 60 ± 0.5 οC, pH 9.5, and the presence of 15 mM CaCl2 and 10 mM NaCl during an hour of treatment retained approximately 40 percent of its activity. Since a batch period of 24 protease production showed similar proteases activity as a  48 h operation,  the following fermentation was conducted within 24 h. The partially purified protease had sound stability in the alkaline pH of 9-9.5 and temperature range of 60 ±0.5 οC in the presence of certain ions like calcium and sodium salt.

L-Asparaginase converts L-asparagine to L-aspartic acid and causes cancer cells to starve. The main idea of the current study was to improve the biochemical properties of this enzyme using immobilization onto modified magnetic nano-particles (NPs). To this end, Fe3O4 NPs were synthesized, coated with an Au shell, and conjugated with cysteine. The formation of NPs and core-shell structures and their morphology were confirmed using Fourier Transform Infrared spectroscopy (FTIR), Energy Dispersive X-Ray (EDX), VU-Vis, Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). Also, Circular Dichroism (CD) and fluorescence spectroscopy were employed for the analysis of the secondary and tertiary structures of the immobilized L-ASNase. The alterations in the kinetic parameters of the immobilized enzyme were analyzed using a Lineweaver-Burk plot. The results of instrumental chemistry analysis confirmed the formation of NPs and core-shell structure, and cysteine binding with the core-shell. Based on CD and fluorescence results, no significant changes were observed in the secondary and tertiary structures of the immobilized enzyme compared to the free one. Kinetic parameters of the immobilized enzyme improved compared to the free enzyme so that Km decreased from 4.43±0.05 to 3.75±0.12 mM and Vmax increased from 187.23±11 to 224.78±16 μM min-1mg-1. Also, the stability of the immobilized enzyme improved with acidic and alkaline pH values compared to the free one at temperatures higher than 50 0C. In addition, the reusability of the immobilized enzyme was superior to the free enzyme, with the immobilized enzyme maintaining 72% of its activity after 15 cycles of catalytic reaction. The immobilized enzyme showed an 86% residual activity after 120 min incubation with trypsin, which was higher than the free enzyme (37%). According to the results of this study, immobilization of L-ASNase onto magnetic NPs can be an efficient strategy to enhance the biochemical properties of this enzyme.

The increase in the incidence of Staphylococcus aureus infections in nosocomial settings each year is a significant concern for the public health sector, as it is one of the most common nosocomial infections. Furthermore, it produces a variety of toxins that aggravate the disease that is being contracted by the host. It was our aim in this study to detect and identify Sccmec typing of MRSA strains isolated from one of the teaching hospitals in Isfahan, Iran, as part of a research project. The presence of different virulence factors was also investigated. To conduct this study, 50 strains were collected from different samples from a teaching hospital in Isfahan for 20 months. Different types of SCCmec were investigated by using multiplex PCR method. Conventional PCR was performed to identify genes of virulence factors including pvl, tst, hlb, sak, eta, and etb. MRSA strains were detected as Sccmec type III in 96% of the cases, and Sccmec type IV in 4% of the cases. The frequencies of hlb, sak , eta, tst, pvl and etb genes in clinical isolates of MRSA were 82%, 50%, 42%, 6%, 4% and 0%, respectively. 10 toxin patterns were observed in the studied MRSA strains. 6 MRSA strains did not have the studied toxins gene. Considering the production of different toxins in MRSA strains and the circulation of one type in the studied hospital it is imperative that an appropriate infection control policy be implemented in order to prevent the spread of MRSA types across a hospital.

The estimation of algal biomass requires monitoring the growth of microalgae. In contrast to time-consuming methods such as cell counting, spectrophotometry was developed as a straightforward, quick, and explicit method to measure biomass concentration. Non-linear models can appropriately describe the patterns of growth and product formation, which are necessary for any biotechnological process using microorganisms. This study investigated the relationship between algal concentration and absorbance in the 600-750 nm wavelength range. Four mathematical growth non-linear models were utilized to analyze and confirm growth curve-based absorbance data obtained from Chlorella sorokiniana and Chlorella sp. The calibration curve was then created by relating the absorbance value (680 nm) with the cell density and dry weight measurements and calculating the correlation coefficient. The absorbance derivative was estimated in order to improve the algal concentration detection limit. A prediction model was created that considered the application of spectrophotometry data to the growth of Chlorella sorokiniana and Chlorella sp. The Exponential Plateau model should be selected to describe the growth of both Chlorella sorokiniana and Chlorella sp. The significance criteria, such as high regression coefficients (R2) and low root-mean-square error (RMSE), indicated that the models used were well-fitted to experimental data and may be considered sufficient to characterize biomass concentration. In addition, percentile deviation revealed that the obtained equations in this study with an error of less than 5% and 10% could be used to estimate densities up to 107 cells mL-1 and dry weight of 0.02-1.24 and 0.03-1.18 g L-1 in Chlorella sorokiniana and Chlorella sp. cultures.

Mycotoxins are harmful toxic metabolites of fungi that are present as contaminants in many foods, dairy, and agricultural products and constitute a potential health hazard. Therefore, novel decontamination approaches for decreasing its bioavailability are of huge interest to improve human safety. In recent years, biological methods have been developed to control mycotoxin contamination. The degradation of mycotoxins (especially aflatoxins (AFs), which are created by the genus Aspergilla species, mainly A. parasiticus, A. flavus, and A. nomius) using microorganisms is an important bio-based method to reduce mycotoxin levels in foodstuffs without the production of harmful intermediates and by-products. Many studies have reported that detoxification occurs by binding the mycotoxin to the cell wall structure of microorganisms. Several factors, including the microorganism strain, the type of toxin, microorganism concentration, the viability of the microorganism, and the contact period, are involved in the detoxification processes. This review discusses the available literature on the biological decontamination of mycotoxins by probiotic microorganisms (mainly), describes the detoxification mechanisms involved in such processes, and the factors influencing the stability of interactions. Future perspectives on this area are also reported. Based on the current data, one should be able to select the most efficient microorganisms to degrade mycotoxins over a wide range of concentrations.