Journal of Applied Biotechnology Reports
Volume:8 Issue: 4, Autumn 2021

Recently, the consumption of probiotics to decrease Oxidative Stress (OS) has been recommended. The present study aimed to assess the effect of probiotics on OS in various diseases as well as in different models in a systematic review study.

Articles were searched through scientific sources such as PubMed, MEDLINE, Wiley, EMBASE, ISI Web of Knowledge, and Scopus by two review authors independently. The keywords that applied to search these articles included: Probiotics, OS, Stresses, Oxidative, and Stress. Results were then combined and reviewed regarding the type of study, type of disease/participants, and outcomes.

In order to conduct this study, 19 eligible studies were investigated. The results showed that various probiotics supplements could improve OS parameters in pregnant women, patients with type 2 diabetics, Diabetic Kidney Disease (DKD) type 2, gestational diabetes mellitus, and the aging process, inflammatory factors in petrochemical workers, acute necrotizing pancreatitis, and polycystic ovary syndrome. However, no significant effect was reported on the oxidative status in patients with Rheumatoid Arthritis.

Probiotics supplements could improve OS biomarkers in various diseases. There are still some controversies about these methods and types of probiotics supplementations. It is recommended that more studies should be conducted for a better decision.

Listeria monocytogenes is a Gram-positive, small rod-shaped bacterium that causes listeriosis in animals and humans from eating contaminated food. It can mostly affect susceptible individuals with defective immune systems. Also, the mortality rates, as a result of listeriosis, can be varied between 30 to 75%. Listeria had been reported to be more allergic to antibiotics than Gram-positive bacteria. However, according to reports, Listeria has recently been allergic to the resistance to these antibiotics. Such an increase in antibiotic resistance in Listeria is in line with the worldwide pattern of the increasing prevalence of antibiotic resistance, including multiple antibiotic resistance in many bacterial groups.Therefore, one of the ways to reduce the incidence of this disease in animals and humans is the biological control of this bacterium by bacteriophage. Bacteriophages have been shown to be effective in controlling L. monocytogenes in food. In 2006, the US Food and Drug Administration approved the preparation of two bacteriophages (Listex™ P100 and LMP-102) for use in certain foods to control L. monocytogenes. The prevalence of foodborne pathogens is the use of phages as biocontrol agents in food. Also, the activation of Phage Listex™ P100 against multiple L. monocytogenes serovars allows it to kill L. monocytogenes and its immunogenicity in food and clinical products. The prevalence of foodborne pathogens is the use of phages as biocontrol agents in food. Also, the activation of Phage Listex™ P100 against multiple L. monocytogenes serovars allows it to kill L. monocytogenes and its immunogenicity in food and clinical products.

Imperialine (Imp) is a steroidal alkaloid present as the main active constituent of medicinal herb, Fritillaria imperialis with many biological and therapeutic effects. However, it has not been investigated in vitro for hypoglycemic effects. Herein, the effects of Imp on cell survival, carbohydrate-hydrolyzing enzymes (alpha-amylase and alpha-glucosidase), glucose uptake ability, insulin secretion levels, Advanced Glycation End products (AGEs) including pentosidine, methylglyoxal, and 3-deoxyglucosone levels and the activity of glyoxalase I as the main factor for degradation of AGEs were examined. C2C12 skeletal muscle and beta-TC6 pancreatic cells were incubated with Imp at concentrations of 0, 25, 50, 75, and 10 μg/ml and the cells were evaluated separately. The biological assays were based on ultraviolet-visible (UV/VIS) spectrophotometric and/or high-performance liquid chromatography (HPLC) methods. Imp had considerable and dose-dependent effects on glucose uptake and insulin secretion (P<0.05). The highest levels of glucose uptake were achieved at a concentration of 100 μg/ml of Imp. Increased glycation index, cytotoxicity, and decreased glyoxalase I activity appeared mostly at concentrations of 75 μg/ml and higher. The studied alkaloid demonstrated remarkable hypoglycemic effect by inhibition of alpha-amylase and alpha-glucosidase. Consequently, the results of the present study revealed possible hypoglycemic effects of Imp and it could be suggested for future studies in the treatment of diabetes mellitus.

The last four decades have recognized the critical environmental issues pertaining to the use of non-degradable synthetic plastics. Currently, the synthesis of biodegradable polymers, like polyhydroxyalkaonoates (PHA) has been gaining considerable interest as a sustainable approach to overcome these issues. The current study was carried out with an objective to optimize the PHA production from Bacillus megaterium JHA. Various nutritional and physico-chemical parameters were optimized using the ‘one factor at a time’ approach. The findings were analysed statistically by one-way ANNOVA and linear regression using the open-source R software. The optimum physico-chemical parameters for maximum PHA production were attained when 5% inoculum size of B. megaterium JHA was added to the JHA medium (pH 8) and incubated at 28 °C for 96 h under shaker conditions (120 rpm). The nutritional parameters were further optimized by addition of 0.6 g% K2HPO4, 0.4 g% KH2PO4, 21 g% glucose, 12.5 mM microcosmic salt, 0.04 g% KNO3, 1 mM MgSO4, and 2 ml trace elements to the JHA medium. The C:N and C:P ratio was adjusted to 70:1 and 20:1 respectively. The growth of bacteria under these optimized parameters allowed 13.71 g/L accumulation of PHA leading to a yield of 54.51%. This resulted in 66.88% increase in yield as compared to the original medium. The scale-up study using a 2 L fermenter further increased PHA accumulation by 4.39% under optimized conditions. The above results clearly indicate that B. megaterium JHA is a promising isolate that can be exploited for the industrial production of PHA.

A Synthetic biomaterial, such as Poly Lactic-co-Glycolic Acid (PLGA) with superior mechanical properties, along with a natural polymer such as fibrin, which facilitates cell attachment and enhances biocompatibility, can be used in the production of novel composite tissue engineering scaffolds. To carry out this study, 10% polymer solutions with different ratios of PLGA: Fibrin, including 10:0, 9:1, 8:2, and 7:3, were prepared and used in the production of aligned and unaligned electrospun nanofiber scaffolds. Human Adipose-Derived Stem Cells (h-ADSCs) were cultured on the scaffolds, and they were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Energy-dispersive X-ray spectroscopy (EDX), Scanning Electron Microscopy (SEM), mechanical, hydrophilic, degradation, water absorption, and biocompatibility tests. The obtained scaffolds consisted of homogeneous fibers, without any beads and water droplets. The percentage of porosities and internal correlation of the cavities were not significantly different between aligned and unaligned electrospun scaffolds (P>0.05) and by adding fibrin, these properties improved, while tensile strength and elasticity decreased. All the scaffolds were hydrophobic and the highest and lowest swelling rates belonged to PLGA/30% Fibrin scaffolds and pure PLGA scaffolds (more than 90% and less than 45%, respectively). There is a significant difference in degradation rates between fibrin-contained scaffolds and pure PLGA scaffolds. Moreover, compared to the aligned electrospun scaffolds, the highest degradation rate of unaligned ones was observed. Considering the results of SEM and bio-compatibility experiments, the aligned electrospun PLGA/10% Fibrin scaffold with numerous spindle shape h-ADSCs and unaligned electrospun PLGA/20% Fibrin scaffold with many spindle shape cells together with round shape cells are introduced as optimal options.

The Luteinizing Hormone (LH) regulates Leydig cell activities through LHR occupation, promoting Gs protein and/or β-arrestin activation. The activated GsαGTP subunit stimulates Adenylyl Cyclase (ACs) and, therefore, intracellular cyclic Adenosine Monophosphate (cAMP) accumulation from the AC substrate Adenosine Triphosphate (ATP). The divalent cations, magnesium (Mg2+) or manganese (Mn2+) associate with ATP to form the real substrates of ACs. In addition, ACs are sensitive to calcium (Ca2+) but in a different way than Mg2+ or Mn2+. Indeed, LH increases the cytoplasmic calcium ion concentration ([Ca2+]cyt) but only when Ca2+ is present in the extracellular medium. In the present study, the effects of intracytoplasmic Ca2+, Mg2+, and Mn2+ on the cyclic AMP response to human LH in mLTC-1 Leydig tumor cells were investigated. The mLTC-1 cells were incubated at 37 °C in media supplemented with and without 5 µM Ca2+, 5 µM Mg2+, or 5 µM Mn2+. The intracellular cyclic AMP accumulation was then monitored under LH stimulation. Our findings revealed that only Mg2+ and Mn2+ in the extracellular medium potentiate the cAMP response to hLH, in contrast to Ca2+. In addition, we also showed that HCO3- increased the stimulation of the adenylyl cyclase enzyme by Ca2+, Mg2+ or Mn2+. In mLTC-1 cells, extracellular Mg2+ and Mn2+ might potentiate LH-stimulated ACs activity by favoring LH interaction with its receptor, whereas Ca2+ from internal stores might be mobilized towards the cytoplasm to increase ACs activity, possibly through the soluble isoform.

Zataria multiflora is an important medicinal plant of the Lamiaceae family in Central and Southern Iran. This plant is at the risk of extinction as a result of wasteful harvesting due to growing demand and high economic value. In this study, the genetic diversity of 25 different accessions of Z. multiflora, collected from provinces including Hormozgan, Fars, Sistan and Balouchestan, Bushehr, Yazd, Kerman, and Isfahan were examined using Inter Simple Sequence Repeat (ISSR) markers. To extract the DNA, five samples taken from the leaves of each accession were transformed into bulks; then, their concentrations were homogenized and 15 primers were used for the remainder of the experiment. The primers produced 83 polymorphic strands altogether, with an average polymorphism percentage of 77.30%; meanwhile, the highest polymorphism percentage (100%) was achieved via primers including 816D, 824H, 836P, and 844S. The lowest polymorphism percentage was obtained from 811C and 834N primers. The results obtained from the Jaccard similarity coefficient in the NTYSIS software showed that the genetic similarity of Z. multiflora accessions varies between 0.32-0.82. The lowest similarities were observed in accessions taken from Fanuj and Ashar, Mehriz, and NasrAbad, and two accessions of Mehriz and Khafr. However, the highest similarities were seen among accessions of NalShah GhandAab and Kerman. In principal component analysis, three of the first components explained 40.44% of changes in the entire data. Following a cluster analysis based on the UPGMA algorithm, accessions were classified into six groups. It can be concluded that the ISSR markers are suitable for examining the genetic diversity of Z. multiflora accessions.

The production of healthy food along with environmental sustenance is an everlasting mission for the coming ages. The utilization of chemical fertilizers may fulfil the requirement but it could also compromise the environment. The present study aimed to tap beneficial microbes that could not only harbour plant growth-promoting traits but could also remove environmental pollutants, nitrate and phosphate. The culture-dependent approach was taken into account to isolate and characterize the bacterial population from dumping ground and mangrove soil. The selected isolates were further tested for remediating nitrate and phosphate by standard biochemical tests. Three isolates from dumping ground and four bacterial strains were proved to contain three out of four Plant Growth-Promoting (PGP) traits (HCN, IAA, Phosphate-solubilisation, and Nitrogen fixation). Two out of three selected bacterial strains were found to have the ability to remove nitrate and phosphate up to 74% and 62% (p< 0.05) respectively. This is while all the other selected bacterial strains from mangrove soil could effectively remove nitrate and phosphate in the range of 62% to 79% and 24% to 100% (p<0.05) respectively. Two novel strains of Streanomonas sp., Alkaligens sp and one each Bacillus sp., Corynebacterium, Pseudomonas, and Citrobacter species isolates were found in the present case. The study represents the dual ability of the novel bacterial strains in plant growth promotion as well as remediation of environmental pollutants. Thus, the study might aid in designing a microbe-based bio-fertilizer for plant growth promotion along with maintenance of soil and environmental health.

Enterokinase (EK) is an enzyme of the serine protease family which is widely used in protein purification. EK acts at the C terminus of the DDDDK site in a protein chain. The enzyme has gained commercial importance in recent times owing to its specificity in biosimilar processing and also while removing the fusion tags in the course of protein purification. The commercial production of EK has faced several challenges and demands the usage of novel strategies. This research shows the construction of a vector using TrpLE1413 (TrpE) as a fusion tag that pushes the produced EK inside the cell towards the inclusion body fraction and produced more of the desired protein in the BL21 (DE3) strain of Escherichia coli. The inclusion bodies produced by fed-batch fermentation were solubilized, refolded, activated, and purified by a single step of anion exchange chromatography. We purified 241 mg/L of recombinant EK, and its purity confirmed by RP-HPLC was greater than 97%. However, the maximum EK yield reported by other researchers is only 106 mg/L. Overall, our results demonstrate the potential of the TrpE fusion tag along with novel expression and purification strategies to increase the enzyme yield by 2-2.5 times when compared to the yield achieved using traditional methods. Hence, this study has paved the way for the industrial production of EK in an economically viable manner. The same strategy could possibly be implemented on the expression of other industrially important recombinant enzymes depending on the protein characteristics.

Rice is one of the most important crops to more than half the world's population. The reduction of rice yield has been severely influenced by drought and salt stress. The main purpose of this survey was to detect Transcription Factors (TFs) involved in drought and salt stress in rice. In this study, microarray data in PlnTFDB and DRTF were taken to evaluate the expression of responsive TFs to drought and salt stress in the growth stages. A comprehensive analysis of responsive TFs were performed containing gene network, expression analysis in different tissues, and detection of Transcription Factor Binding (TFBs) sites. A total of 80 TFs were found differentially expressed (DEGs) under drought and salt stress in rice. Gene Ontology (GO) revealed that biological processes included transcription, regulation of transcription, regulation of RNA metabolic, and RNA metabolic. In addition, some molecular functions such as organic cyclic compound binding, heterocyclic compound binding, DNA binding, and cellular component are enriched in intracellular and nucleus. To survey selection pressure in responsive TFs under drought and salt conditions, Tajima’s and Fu test analysis revealed balancing selection. Analysis of TFBs illustrated that several TFBs namely AP2, bZIP, and MYB/SANT act as basic TFBs linked to abiotic stress responses as well as different growth stages in rice. The current study revealed that most TFs related to histone modification were up-regulated whereas, TFs associated with the regulation of repression/ activation transcription were down-regulated. Our results can provide an insight into the regulatory mechanisms involved in response to drought and salt stress which can aid to improve rice varieties.

Rodent pests are unique threats to agriculture and food security in many developing countries. Hence, this study investigated some physicochemical properties of partially purified arginase from the stomach of cane rats (Thryonomys swinderianus). This was with a view to understanding the significance of the enzyme in nitrogen metabolism, which could be exploited in the control of rodent pests. Arginase was isolated and subjected to 70% ammonium sulfate (NH4)2SO4 precipitation and dialyzed. The dialysate was further purified using ion-exchange chromatography on CM-Sephadex C-50 matrix. Apparent Km of the enzyme for L-arginine and Vmax were 54 ± 0.7 mM and 0.057 ± 0.1 μmol/minute/ml, while the optimum pH and temperature obtained for the enzyme were 7 and 70 °C, respectively. NaCl, MnCl2, and HgCl2 activated the enzyme activity, while FeCl3 totally inactivated the enzyme at tested concentrations. β-mercaptoethanol, urea, and EDTA profoundly potentiated the activity of the enzyme. Enzyme activity (81%) was retained when arginine was substituted with cysteine, while histidine, proline, alanine, tyrosine, and tryptophan had potent inhibitory effects on the enzyme activity. The study established the presence of arginase in the stomach of cane rat and illuminated some physicochemical properties of the enzyme, which could be exploited in its deployment as a viable strategy to control T. swinderianus. However, further studies including structure-function investigations of the enzyme are recommended to fully exploit its potential in the control of rodent pests.

Cholera is a lethal diarrheal disease caused by Vibrio cholerae. Cholera toxin (CTX) is one of the major virulence factors in V. cholerae pathogenesis. One of the major strategies in dealing with the poisoning of the bacteria is their rapid detection. The aim of this study was to design and set up a double-sandwich ELISA diagnostic method for the direct detection of cholera toxin B (CtxB) based on chicken immunoglobulin Y (IgY) and rabbit immunoglobulin G (IgG).

Recombinant CtxB protein was expressed in E. coli BL21 (DE3) cells by addition of IPTG and was purified using an NiNTA column. Chickens and rabbits were immunized subcutaneously and the generated antibodies were purified from egg yolks by polyethyleneglycol (PEG) precipitation and from the rabbits' sera by protein G column. These antibodies were used to set up the ELISA method. The sensitivity of the designed ELISA method was evaluated using serial dilutions of the protein and the specificity of this method was evaluated.

Recombinant protein expression analysis showed an appropriate expression of the protein (300 µg/ml). ELISA assay results showed an increased serum antibody levels against the protein in rabbits’ and chickens’ sera after each injection. The yield of the purified IgY and IgG was 10 and 2.5 mg/ml, respectively. The sensitivity of the ELISA method was about 39 ng for recombinant CtxB. The results showed the high specificity of this technique.

Results suggest that IgY/IgG-based sandwich ELISA in this study provides a convenient preparation for the development of an immune-based method for the detection of CtxB.

The effluents produced as a result of the dyeing process, especially by textile industries are a major threat to sustainable environmental development. Several challenges are observed in the treatment and disposal of complex azo dyes like Reactive Red 120 (RR120). The aim of the present study was to optimize the dye decolorization/degradation process by bacterial consortium. The consortium consisted of three potential azo dye degraders i.e., Shewanella haliotis RDB_1, Shewanella putrefaciens RDB_2, and Aeromonas hydrophila RDB_3. It was prepared in 1:1:1 ratio and was named as RAR. This consortium was optimized under several nutritional and physicochemical parameters for effective decolorization of RR120. Complete decolorization of 50 ppm RR120 was achieved with 10% inoculum of 1.0 OD540 nm in 3% Yeast Extract (YE) medium under static conditions in 4 h. The optimum decolorization was observed between pH 7-8 and temperature 30°C-35°C. However, the consortium RAR showed significant activity between a pH range of 6-10, temperature 25°C-45°C and NaCl concentration up to 10%. The electron acceptors like nitrate and nitrite salts, and electron donors like urea and casamino acids negatively affected the decolorization rate of RR120. The sugars and organic acids failed to support decolorization in M9 medium. However, a varying effect was observed in the 3% YE medium. Soymeal peptone (prepared in distilled water) supported considerable decolorization but was not as effective as 3% YE medium. Considering the above features and tolerance of consortium RAR to varied range of pH, temperature and NaCl concentration, it may be a suitable candidate for biodecolorization of textile effluents.

The genus Exiguobacterium includes psychrotrophic, mesophilic, and moderate thermophilic strains and species that have been isolated from extreme environments, including very cold or hot environments. The genus Exiguobacterium has received much attention in biotechnology, and related industries due to secretory enzymes with high enzymatic activity and consequently stable enzymes capable of tolerating extreme conditions. The aim of the present study was to introduce and describe the phenotypic and the genotypic characterization of a novel species of genus Exiguobacterium isolated from the Ilam mountains, Iran.

Genotypic features were analyzed using universal genes (gyrB, hsp70, rpoB, and citC) belonging to the Exiguobacterium genus. Also, cspC1, nusA, and dnaJ genes were used to confirm the profile of new psychrotrophic strains. The distinctive phenotypic characteristics of the new strain with the most famous strains of the genus Exiguobacterium were investigated. All statistical analyses were conducted using R Packages for data visualization and exploratory data.

A motile, Gram-stain-positive, rod-shaped, non-sporing, tolerant up to 5% NaCl, grew at 0-25 °C and pH 6 and 9, designated Exiguobacterium sp. HA2 was isolated from the soil. The major isoprenoid quinone is MK-7 and in the smaller amount are MK-6 and MK-8. The major cellular fatty acids (>10 %) were isoC13:0, isoC15:0, and C16:0. To adapt to low temperatures, Exiguobacterium sp. HA2 upregulated expresses cold shock response including cold shock protein (CSP) and transcription elongation protein NusA. Also, downregulated expression of heat shock protein DnaJ domain protein.

In the current study we investigated the difference in the genotype, phenotypic, and functional characteristics of Exiguobacterium sp. HA2. It can be regarded as representing a novel psychrotrophic species within the genus Exiguobacterium.