Journal of Applied Biotechnology Reports
Volume:8 Issue: 3, Summer 2021

One of the main reasons for the high prevalence of SARS-CoV2 is the high speed of its replication and reproduction. The replication inhibitors are under investigation due to the importance of prevention of the spread of coronavirus disease 2019 (COVID-19). In coronavirus replication, the virus enters the cell by endocytosis. After uncoating, the positive-strand RNA is translated to produce the non-structural protein (NCP) precursors. These precursors are cleaved and form mature, functional helicase and RNA polymerase. A replication-transcription complex (RTC) is then formed. Targeting the various stages of this process may be useful in preventing the spread of this epidemic. According to the similarity of the COVID-19 replication to the other single-stranded RNA viruses such as HCV, Ebola Virus, and Marburg, the best way to prevent the spread of infection is the viral genome replication targeting with specific drugs after exposure to the virus. For COVID-19 medications, compounds that target SARS-CoV2 replication are being tested in silico, in vitro, or in vivo. According to other clinical trials that have been applied for SARS-CoV and MERS-CoV inhibitor drugs in the attachment, protease, and replication stages can prevent the virus from multiplying.  By reviewing previous related articles in this field, in this review article, we have tried to focus on all the information related to genome replication and categorize known drugs that have been applied as clinical trial treatments. The use of these drugs and other medications seems to be effective in reducing the prevalence of COVID-19.

Antimicrobial resistance (AMR) has become a menace for humanity. Several antibiotics have become ineffective, and there is a need for a novel route or approach to find solutions. Antimicrobial peptides (AMPs) have already generated a lot of noise for over four decades. However, insect-based AMPs offer not only novel sources but also provide effective measures, as the insects are known to be exposed to extreme environments. Plenty of insect-based AMPs have been identified from different orders of insect taxonomy. This review concentrates on the world of insect-based AMPs, their known targets and their applications in agriculture and medical fields. Transgenic induction of AMPs in different hosts has been successfully studied in plant systems. By identifying new AMPs, it will also help in the field of agriculture to increase the production rate of the crops by eliminating the disease-causing pathogens, microbes, and pests. In the present review, we have discussed recent knowledge, and several essential medical and agricultural importance of AMPs identified from insects.

With the advent and development of the science of immunology, molecular biology, microbiology, genetic and biochemistry, human beings embarked on vaccines and deployed them. Since the birth of vaccine by Edward Jenner, there has been great progress in the production of various vaccines against different pathogens and antigens. Due to increased infectious diseases and multi-drug resistant strains, one of the best ways to encounter them is through vaccination. There are various vaccines with some problems which are the result of various mechanisms for the escape of pathogenic microbes from the immune system. Therefore, there is a need for comprehensive vaccines that can provide extensive immune responses. Chimeric vaccines and recombinant chimeric vaccines are developing nowadays and can protect against different serovars. The first recombinant vaccine was introduced in the mid‑1970s against the hepatitis B virus (HBV). Recombinant chimeric proteins are developing nowadays that have the advantage of both recombinant and chimeric properties.

Bioplastics are biodegradable polymers of biological origin. The exhausting fossil resources and ever-increasing environmental pollution caused by plastics derived from these resources are driving the growth of the bio plastic industry. There is increasing focus on developing low-cost and durable bio-based plastics, with a wide range of applicability. Currently, a majority of raw material for bioplastics production comes from agricultural crops, which indirectly poses threat to food security. Hence using organic wastes from biological origins, will not only limit our dependency on agricultural crops, but may also assist in solid waste management, in an effective manner. Industries, particularly food and agriculture sector, produce significant amounts of organic wastes, which can be harnessed for this purpose. It will also reduce the cost of production to a remarkable extent. Hence, this review focuses on the types of bio-based plastics and gives an insight on biological wastes that can be utilized to produce such plastics. It is indeed, the need of time to intensify innovations and research in this field to overcome the hindrances and developing viable processes for manufacturing bio-based plastics. This environmentally friendly approach can remove our dependency from fossil-based conventional polymers and will lead us to a much more sustainable future.

Stem cells are unique biological cells that can differentiate into specialized adipocytes. In mammals, there are two broad types of stem cells: embryonic stem cells that break away from the blastocyst cell proliferation, and adult stem cells that are found in different tissues. Mesenchymal Stem Cells (MSCs) are multipotent cells that are one of the most important adult stem cells. Due to their high proliferative capacity and the proper self-renewal ability, they have provided a powerful and promising source to use in the field of repair plaque. Also, MSCs can differentiate into several cell types, such as: osteoblasts (adipocytes), chondrocytes (chondrocytes), adipocytes (adipocytes) and myocytes (muscle cells). Because of the importance of MSCs as a source of autologous transplantation in the field of regenerative medicine, in depth studies of involved cell and molecular signaling cycles are needed. These cycles are the reason in which these cells are able to differentiate into other cell types. Also, the molecular changes that occur during these cells differentiation are needed to be closely examined. The role of cytokines, chemokines, and transcription factors on the process of differentiation of these cells is considered significant. The differentiation of MSCs into other cell lines is manipulated and stimulated by specific transcription factors associated with specific cell lines, thus, the important role of non-coding small mRNAs (miRNAs) is increased as a result. In the following study, the process of differentiation of MSCs into the chondrogenic lineage and the effect of several miRNAs on the regulation of the process of differentiation into adipose-derived stem cell cartilage have been scrutinized.

Coronaviruses are significant pathogens of both human and animals and are globally distributed. Out of seven CoVs strains, the most lethal coronavirus strains being portrayed is SARS-CoV-2. It can cause bronchial asthma, and severe pneumonia and acute respiratory disease. Due to its contagion in infants, adults, and immunocompromised patients which further results in making this a deadly disease, thus there is an urgent need to develop effective and safe therapeutics against it. Meta-analysis of publicly available gene expression datasets belonging to SARS-CoV-2, SARS-CoV, MERS-CoV, and HCoV-229E were carried out to identify the potential differentially expressed genes exclusively associated with SARS-CoV-2, and then a network model was developed to decipher significant drug targets, associated pathways and drug candidates which can be repurposed for this infection. The COVID-19 infection mainly targets immune responses and regulatory processes. A novel role of Relaxin signaling pathway was identified in SARS-CoV-2 infection. Anti-inflammatory, anti-tumor, nutraceutical and anthelmintic agents were found to be good prospective candidates for repurposing against COVID-19. This theoretical study resulted in the identification of approved drug targets that may have the potential to be repurposed for COVID 19 treatment.

All sulfur organic odorants used in the Iranian gas industry enter the country in 200-liter barrels. There are ways to clean up the empty barrels contaminated with these materials. In the Gas Company, the currently used method is chemical oxidation (using sodium hypochlorite and caustic). In this study, the biological desulfurization and degradation method of mercaptan was studied. Desulfurizing bacteria in the university microbial collection, together with bacteria isolated from gas odorant barrels, were examined, among which one of the species had the highest and fastest decomposition rate. This bacterium belongs to the Bacillus cereus family. The most important factors affecting biological desulfurization including initial bacterial concentration, the concentration of odorant, and the Oil Fraction Phase (OFP) were optimized. These three factors were studied using an experimental design. Initial bacterial concentrations were evaluated at five levels from 10 to 50 ml with an optimum concentration of 30 ml. The OFP was also evaluated at five levels from 10 to 90%, with 50% being optimized. Concentrations of odorant were also evaluated from 2500 to12500 ppm, with an optimum concentration of 7500 ppm. Operational testing was carried out in one of the barrels in the optimized conditions for 48 h. The results showed 79.8% efficiency in removing odorant.

Methomyl (MET) is a monomethyl carbamate insecticide that is widely used around the world. MET is highly toxic to humans via oral exposure and mainly affects the liver tissue. It actually induces toxicity through overproduction of Reactive Oxygen Species (ROS) leading to oxidative stress with subsequent destruction of lipids, proteins, and nucleic acids.

Various plant extracts have been primarily screened for their antioxidant activities by measuring the free radical scavenging ability. Later, the plant extract with the highest antioxidant efficacy has been further formulated into a nanosuspension and the antioxidative effect has also been investigated against MET. Additionally, liver, kidney, and heart function biomarkers, liver tissue oxidative stress parameters, and total antioxidant capacity were assessed. Moreover, RT-PCR was applied to measure the Nrf2 expression.

The antioxidant screening data showed that balanites extract (BLT, Balanites aegyptiaca) had the most potent antioxidant activity. Besides, BLT showed dose-dependent improvement in liver, heart, and kidney functions in experimental mice treated with MET. The antioxidant biomarkers in liver tissue and total antioxidant capacity were elevated as compared to the MET-treated group. Furthermore, BLT significantly ameliorated MET-induced toxicity via the induction of Nrf2 and MET hepatic clearance. This study suggests the potential use of BLT extract as a natural antioxidant for the safe management of MET-induced hepatotoxicity and oxidative stress.

Based on the presented data in this study, it can be concluded that BLT or BLT-NS can be used as a safe drug for methomyl toxicity.

The large amount of production and use of pomegranate in Iran has made the waste of this important product a suitable source for the production of bioethanol. This research examined the ability of Zymomonas mobilis for producing bioethanol from Pomegranate peel. The hydrothermal treatment method and enzymatic hydrolysis were used to release the fermentable sugars from PP particles. Cellulase loading of 30 U/g solid was used for enzymatic hydrolysis. Zymomonas mobilis PTCC 1718 was used as the ethanol-producing strain. The Response Surface Methodology experimental design was performed to optimize the fermentation process conditions for maximum ethanol production and minimum fermentation time. The amount of sugar released after hydrolysis was about 18.37% of the fresh PP weight. The amount of meat peptone and yeast extract (as nitrogen sources added to the medium), bacterial dry weight (as inoculum) and fermentation time were considered as the effective factors in the RSM experimental design. The maximum amount of 0.218 g ethanol was produced at 0.37 g meat peptone, 0.28 g yeast extract, 0.021 g bacterial dry weight and 30 h fermentation time (in 50 ml of culture medium). The maximum ethanol production yield of 45.5% (which is 89.2% of the theoretical yield) was achieved in this process. Z. mobilis has good ability for producing bioethanol from PP. However, more research should be conducted in order to industrialize the process.

The repair process of severed peripheral nerves is conducted by the bridging of the regenerating neural fibers across a gap in the case of the existence of an appropriate route (space) between the proximal and distal severed stumps. The current study aimed to improve the transected sciatic nerve of rats with a 10 mm gap by means of applying electrospun conduits composed of polymer nanocomposites of polyglycolic acid (PGA), collagen, and nanobioglass (NBG). Then, the efficacy of the designed conduits (PGA/collagen/NBG, PGA/collagen, and PGA alone) was histologically and electrophysiologically compared with autograft nerves to determine whether these conduits have superiority over the autograft procedures in the process of nerve regeneration.

In this experiment, 50 healthy adult male Wistar rats underwent sciatic nerve transection. After four, eight, and 12 weeks of the surgical procedures, the therapeutic effects of conduits on sensory and motor recovery of transected nerves were evaluated.

The analysis of the functions of motor and sensory nerves showed marked improvement in rats treated with PGA/collagen/NBG conduit. Also, histological staining and immunohistochemical assessment of the expression of NF200, S100, and CD31 proteins revealed newly-formed nerve fibers with micro blood vessels at the proximity of regenerated nerve fibers.

It seems that due to the high surface area of electrospun nerve conduits to adhere the cells, the application of these compounds would be beneficial in clinical practice in the future. The results suggest that PGA/Collagen/NBG nanofibrous conduit possesses the highest capability in increasing nerve regeneration following nerve transection in murine models.

Bioremediation and biodegradation are considered as environmental friendly techniques for contaminants’ removal in polluted environment. In this study, the removal and kinetics of Tetrachloroethene (PCE) and Trichloroethene (TCE) microbial degradation, their inhibitory effects and the rate of dehalogenation capacity at high concentration of PCE were investigated.

Dechlorinating culture was provided by Bioclear B.V. from a PCE-contaminated site (Evenblij in Hoogeveen -The Netherlands). The batch apparatuses were placed in an orbital shaker at 150 rpm at room temperature. In all the 18 batches, 6 different concentrations of PCE were measured from 0.1 mM to 0.6 mM. The degradation rate of PCE, Trichloroethene (TCE), and cis-1,2-dichloroethene (cDCE) were determined by the PHREEQC model.

The results revealed that the final product was ethene and the rate of dechlorinating of PCE increased gradually. The degradation process started after 3 days in batch modes (0.1 mM). After 10 days, the dechlorination of PCE to TCE was obtained in a low concentration of PCE (0.1 mM). Also, the TCE concentration became close to zero after 10 days. However, the start point was longer than PCE and the rate of biodegradation of TCE was faster than PCE. PCE did not show any progress in the dechlorinating procedure at 13th and 14th batch series and none of the daughter products were observed.

It should be concluded that there was no single organism that could dechlorinate PCE to ethene, directly. Therefore, the best consortium of microorganisms to dechlorinate PCE to ethene faster, with less production of VC as the most hazardous compound, should be studied.

The present study was focused on the statistical optimization of growth parameters for enhancing the Microbially Induced Calcite Precipitation (MICP) using ureolytic yeast strain. Thirteen yeast strains were tested for the synthesis of urease enzyme by phenol-hypochlorite assay and were further evaluated for calcite precipitation test. The growth parameters were optimized using the best ureolytic strain by Box-Behnken Design (BBD) and the extracted MICP was characterized through instrumental analysis. Among thirteen yeast strains, Candida tropicalis NN4, Spathospora sp. NN04, Wickerhamomyces anomalus VIT-NN01 and Candida dubliniensis NN03 showed positive results for the synthesis of urease enzyme. Spathospora sp. was found to be the most potent strain for MICP. A significant enhancement in MICP by Spathospora sp. was observed under optimized conditions viz. A-urea concentration (80.0 g/L), B-calcium chloride (45.0 g/L), C-pH (9.0) and D-inoculum dosage (8%, v/v). The actual value (34.4±0.12 g/L) was in agreement with predicted value (34.7±0.01 g/L) with the R2 value (0.9900), confirming the validity of the model. The FTIR of MICP confirmed the fundamental bands of CO3 stretching and bending vibrations, observed at 1394.23 and 874.85 cm-1. The Scanning Electron Microscope (SEM) images of biomotar revealed aggregated polymorphs of MICP interconnected with yeast mycelium and spores. The Energy Dispersive X-Ray Spectrometer (EDX) analysis indicated the presence of calcite in the biomotar. A remarkable improvement in the compressive strength (28 to 44 MPa) and morphological changes were observed in biocement mortar as compared to cement mortar. This result is the first report on the implementation of ureolytic Spathospora towards the application of biocementation through MICP using BBD.

The present study has introduced a simple and rapid tissue culture system aimed at in vitro regeneration of Artemisia diffusa and in vitro artemisinin production in its genetically transformed culture. An in vitro regeneration of A. diffusa was developed using different combinations of plant growth regulators including Naphthalene Acetic Acid (NAA), Indole-3-Acetic Acid (IAA), Thidiazuron (TDZ) and Benzyl Adenine (BA). Also, an efficient genetically transformed root induction system for A. diffusa was developed through Agrobacterium rhizogenes- mediated transformation using four bacterial strains, A4, ATCC15834, MSU440, and MAFF-02-10266. The stem and leaf of one month old sterile plants of A. diffusa were used as explants. Molecular analysis of transformed root lines was confirmed by PCR using primers specific for the rolB gene. The highest regeneration occurrence was obtained using MS medium containing 0.5 mg/L TDZ and 0.1 mg/L IAA (75%). Root induction was obtained on MS medium supplemented with 0.5 mg/L IBA. The results showed a significant increase in transformation frequency when the strain MSU440 was used (80.7%). Approximately 0.05 % artemisinin was detected by High-performance liquid chromatography (HPLC) analysis in root cultures. To the best of our knowledge, this is the first report of A. diffusa in vitro organogenesis and transformation. This study describes an efficient protocol for hairy roots culture of A. diffusa which can be used for scaling up the plant active phytochemicals or for genetic manipulations of the plant.

Toxic metal ion contamination is one of the most important environmental issues in the world. Wastewater of mines and certain industries are known sources of environmental heavy metal contaminations. Also, Copper (Cu) contamination is a common issue. Using biological tools particularly bacterial-derived compounds could be appropriate for bioremediation. 

In this study, the Cu2+ uptake from Chah Musa mine wastewater by three different Bacillus species was assessed using the batch equilibrium isotherm. The impact of pH, exposure time, temperature, and the bioabsorbent dose on the adsorption of Cu2+ ions was assessed. Also, the kinetics and isotherm models of Cu2+ ions adsorption were studied for three different Bacillus species.    

The results showed that the maximum removal Cu2+ ions (99%) was obtained for Bacillus thuringiensis biomas. The correlation coefficient value (R2) of Freundlich isotherm was higher than Langmuir isotherm indicating better metal uptake based on the Freundlich model. The rates of adsorption for all bioadsorbant were attained to be conforming to the pseudo-second-order.

According to the current study, all three dead Gram-positive Bacillus spp. are favorable and effective candidates for the removal of Cu2+ from aqueous solutions and industrial wastewaters.