Electronic Journal of Biotechnology最新文献

Background

The interest in ultraviolet (UV) radiation from the sun and artificial sources has been recently increasing due to its toxic effects, including sunburn, erythema, photodamage, and photocarcinogenesis. In this study, we aimed to develop a valuable nanomaterial that can block total UV rays using an undervalued, yet profitable marine organism. We successfully developed carbon nanodots (CNDs) and a CNDs-polyvinyl alcohol (PVA) composite film that effectively protect against UV-A, UV-B, and UV-C radiation based on a common brown algae, sea cauliflower (Leathesia difformis), through simple hydrothermal synthesis in aqueous solution.

Results

CNDs-PVA film protected rhodamine B from photobleaching and polydiacetylene vesicles with 10,12-tricosadiynoic acid from polymerization. As-fabricated CNDs in aqueous solution blocked >99% of UV-A light, which causes photoaging and skin cancer. The CNDs-PVA film showed excellent transparency, with >84% transmittance of visible light, and effectively blocked >60% of UV-A/B and >30% of UV-C rays under direct and strong irradiation.

Conclusions

This preliminary work indicates that CNDs based on underutilized marine brown algae have strong potential for application in technologies for wide UV protection.

How to cite: Kim KW, Kwon YM, Kim SY, et al. One-pot synthesis of UV-protective carbon nanodots from sea cauliflower (Leathesia difformis). Electron J Biotechnol 2022;56. https://doi.org/10.1016/j.ejbt.2021.12.004

Background

Exons are an important part of genes. However, there has been no molecular marker technique based on single primer amplification developed for exons region.

Results

A novel molecular marker technique called exon based amplified polymorphism (EBAP) which used single primer to perform the PCR was developed. Single primers were designed based on the rich GC bases in the exon region of genes. The single primer consists of filling sequence, intermediate core region sequence and selective bases sequence. The filling sequence has a total of six bases, which can be 2A and 2T or 3A and 3T. The intermediate core region sequence consists of eight bases, all of which are G and C, but at least 2G or 2C are required. The first of the three selective bases must be either A or T, and the second and third are arbitrary bases. Due to the principle of primer design, these single primers should be universal. We applied it to the DNA polymorphisms detection of maize, sugarcane, potato, cassava, cabbage, and peanut. The results showed that it detected more abundant DNA polymorphisms in the first five crops, but not in the cultivated peanut. In addition, different band patterns were obtained by amplifying peanut cDNA with different single primers.

Conclusions

We have developed a novel and universal molecular marker technique. It is simple, fast and efficient. It does not require genomic sequence information. It can be widely used in germplasm identification, genetic diversity analysis, and molecular fingerprinting. How to cite: Xiong F, Liu J, Tang R, et al. Exon based amplified polymorphism (EBAP): A novel and universal molecular marker for plants. Electron J Biotechnol 2022;56. https://doi.org/10.1016/j.ejbt.2022.01.001.

Background

Spodoptera frugiperda (Sf-9) cells are often used to produce recombinant proteins by transient expression. The culture medium contributes to the efficiency of protein production, but the effect of modern insect cell culture media on Sf-9 cells has not been evaluated for different transient expression systems. Accordingly, we compared the baculovirus expression vector system (BEVS) and lipopolyfection (LP) for the production of schistosomal ALDH and the antimicrobial peptide BR033, respectively. We used Sf-9 cells adapted to four commercially available media: TriEx ICM, ExpiSf CDM, Sf-900 II SFM and IS Sf Insect ACF.

Results

During cell maintenance, the highest viable cell density was achieved using IS Sf Insect ACF, but the shortest doubling time was observed in TriEx ICM. All four media supported transient expression with standard protocols for LP and BEVS. We confirmed the typical switch in metabolic rates (glucose, lactate and amino acids) after transfection or infection, comparable to previous reports. The maximum protein production rates were 0.26 ± 0.04 amol/(cell h) for LP and 4.63 ± 1.85 amol/(cell h) for BEVS, both achieved using Sf-900 II SFM.

Conclusions

The experiments demonstrate that the most suitable medium for transient production in Sf-9 cells depends on the experimental objectives or production framework. We therefore recommend implementing the screening of different media during process development.

How to cite: Käßer L, Harnischfeger J, Salzig D, et al. The effect of different insect cell culture media on the efficiency of protein production by Spodoptera frugiperda cells. Electron J Biotechnol 2022;56. https://doi.org/10.1016/j.ejbt.2022.01.004.

Background

The emergence of multidrug-resistant (MDR) microorganisms is one of the biggest and most challenging public health issues drawing considerable attention of the scientific community. Here, we present an easy, one-step, inexpensive and ecofriendly/biologically mediated synthesis of Aloe vera-conjugated silver nanoparticles (Av-AgNPs) where the aqueous plant extract acts as a reducing and stabilizing agent and the resultant conjugate exhibits remarkable potential to limit/inhibit the growth of MDR pathogens.

Results

The nanosynthesis concluded in 4–6 h at 65°C and was followed by detailed characterization of the bioconjugated Av-AgNPs (with and without fabrication on cellulosic materials i.e., cotton fabric and filter paper) using a combination of UV–visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), x-ray diffraction (XRD) and inductively coupled plasma optical emission spectroscopy (ICP-OES). The so-characterized NPs showed growth inhibitory effects on multiple strains including the Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli (E. coli), Acinetobacter baumannii (A. baumannii), Pseudomonas aeruginosa (P. pseudomonas) and, more importantly, the fungus Candida albicans (C. albicans), when analyzed using the Kirby-Bauer method. A notable reduction in the colony-forming unit (CFU) counts of the E. coli (present in contaminated drinking water) was also observed when the filter paper encrusted with Av-AgNPs was applied as a filtration material.

Conclusions

In conclusion, the biofabricated Av-AgNPs are easy to synthesize and are a cost-effective alternative to inorganic AgNPs, with considerable antimicrobial activity, deserving further investigations for biomedical applications.

How to cite: Arshad H, Saleem M, Pasha U, et al. Synthesis of Aloe vera-conjugated silver nanoparticles for use against multidrug-resistant microorganisms. Electron J Biotechnol 2022;55. https://doi.org/10.1016/j.ejbt.2021.11.003

Background

Antimicrobial substances from medicinal plants have been widely applied in many industries, without the concern of side effects. Nonwoven fabric products such as face masks, paper wipes, and wound dressings contain antibacterial substances for reduction of bacterial accumulation. Therefore, the use of bioactive compounds from medicinal plants improves the properties of fabrics. This study used a crude extract from Caesalpinia sappan to perform phytochemical screening and investigate its antibacterial activity, stability, hemolytic activity, and preliminary application in nonwoven fabric products.

Results

The alcoholic crude extracts of C. sappan heartwood consisted of alkaloids, anthraquinones, coumarins, flavonoids, saponins, tannins, terpenoids, and cardiac glycosides. The C. sappan extract (CSE) had the highest inhibitory activity against Staphylococcus aureus with inhibition zone of 13.67 ± 1.56 mm in the agar well diffusion assay. The MIC value of CSE was at 1.95, 1.95, and 0.98 mg/ml, while the MBC value was 62.5, 3.91, and 31.25 mg/ml for S. aureus, Bacillus cereus, and Vibrio parahaemolyticus, respectively. The phenolic content was stable at 28 ± 2°C and at pH 4.0 for 12 h (∼95%) and 10 d (>90%), and it had low hemolytic activity on human erythrocytes at 5.04–18.95%. The major chemical component was flavonoids, and brazilein was 1.88% area sum. For the application to antibacterial fabrics, the highest inhibitory activity against S. aureus was found in 2MIC of CSE-coated fabric with 99% for 3 h.

Conclusions

The CSE had high inhibitory toward 3 bacterial strains and stability in a wide range of pH and temperature. The CSE-coated nonwoven fabric had efficient inhibition to S. aureus and a possibility to application in a nonwoven product in the future.

How to cite: Hemthanon T, Ungcharoenwiwat P. Antibacterial activity, stability, and hemolytic activity of heartwood extract from Caesalpinia sappan for application on nonwoven fabric. Electron J Biotechnol 2022;55. https://doi.org/10.1016/j.ejbt.2021.10.002

Background

Governments around the world have developed a variety of strategies to address the long-standing food crisis. Food contaminated by genetically modified organisms (GMOs) and meat residues from hormonally treated animals, has recently received increased attention, posing serious health risks to consumers. The aims of this study are to detect recombinant DNA in genetically modified maize, soybeans, and fruits. Furthermore, meat adulteration by mixing meat from different animal species and ractopamine residues (RAC) in imported and local food products were detected using qualitative and quantitative methods.

Results

Sixty local and imported food samples were collected from different supermarkets, local markets, street vendors, and slum areas in Egypt. The results revealed that the recombinant DNA targeted sequences were detected in 25 samples, with the common regulatory genes (CaMV35s) found in 16 of them. The Bt-11 and RRS genes were both detected in maize and soybean samples. However, 35 were used for a screening of meat adulteration with meat from different animal species using qualitative real-time PCR and RAC residue detection using ELISA. The results revealed that 11 samples of pork were positively adulterated, and six samples of meat were positively adulterated (dog, donkey, pork, horse, sheep, chicken, and soybean). Finally, lard was detected in three positively adulterated porcine meats.

Conclusions

It is concluded that, as per the international regulations, in order to protect consumers from the harm caused by food adulteration, countries must recognize and implement highly restricted labelling systems, as well as qualitative and/or quantitative methods in routine analyses in internationally accredited laboratories.

How to cite: Mostafa AA, Abu-Hussein AE-HG, ElRouby MT, et al. Food adulteration with genetically modified soybeans and maize, meat of animal species and ractopamine residues in different food products. Electron J Biotechnol 2022;55. https://doi.org/10.1016/j.ejbt.2021.11.005

Background

As a kind of rare sugar alcohol, allitol has important application values in food and medication. In addition, it can be used as a key substrate to produce other d/l-rare sugars. Allitol can be effectively produced by the resting-cell biotransformation method.

Results

Two recombinant Escherichia coli strains, one simultaneously expressing ribitol dehydrogenase (RDH) and formate dehydrogenase (FDH) in fusion (fusion expression strain for short) and the other expressing the above two enzymes individually (individual expression strain for short), were respectively constructed and used for allitol bioproduction. The produced allitol was confirmed by HPLC, mass spectrometry, and polarimetry. The individual expression strain had higher activity, which produced 58.5 g/L allitol from 90 g/L d-allulose (also named d-psicose) in 1 h with an allitol productivity of 58.5 g/L/h under optimized conditions.

Conclusions

The constructed individual expression strain had the highest allitol productivity among the reports. The production process developed in this study was simple, highly efficient, and had the potential for mass production of allitol.

How to cite: Wen X, Lin H, Ren Y, et al. Allitol bioproduction by recombinant Escherichia coli with NADH regeneration system co-expressing Ribitol Dehydrogenase (RDH) and Formate Dehydrogenase (FDH) in individual or in fusion. Electron J Biotechnol 2022;55. https://doi.org/10.1016/j.ejbt.2021.11.007

Background

Marine fungi are considered as a promising source of pharmacologically important extracts and compounds owing to the new chemical structures that they can synthesize due to the environmental conditions of their habitat. The aim of this work is to evaluate the free radical scavenging capacity of methanolic extracts from marine fungi and their relationship to their total phenolic content. For this, the radical tests ABTS, DPPH, and Galvinoxyl were used, comparing these results with the antioxidant Trolox as reference. The total phenol content was quantified using the Folin-Ciocalteu method. All data were analyzed by ANOVA followed by Tukey's post hoc tests (p < 0.001).

Results

The results indicate that Fusarium oxysporum broth extract (Apl) showed a greater capacity for free radical scavenging when compared with the Trolox standard (128% ABTS) as well as the biomass extract of Cladosporium cladosporioides (A.c) with values of (107 % ABTS and 102% Galvinoxyl). In addition, the variation found in the total phenolic content for each bioactive extract suggests that their antioxidant activity is not exclusively related to phenolic compounds and hence might be attributed to other types of metabolites.

Conclusions

This work is the first to report the antioxidant capacity of marine fungi isolated from sponges and corals in Mexico. These results, we consider, support the selection, conservation, and use of marine fungi as an alternative source of phenolic and non-phenolic compounds that could be used in pathologies such as oxidative stress and cancer, among others.

How to cite: Couttolenc A, Medina ME, Trigos Á, et al. Antioxidant capacity of fungi associated with corals and sponges of the reef system of Veracruz, Mexico. Electron J Biotechnol 2022;55. https://doi.org/10.1016/j.ejbt.2021.11.002

Background

The use of single cell protein (SCP) has become a method for alleviating the shortage of protein feed that microorganisms propagate in a suitable culture medium. In this study, SCP was produced by yeast to use the nutrition contained in the biogas slurry of chicken manure.

Results

The results showed that Galactomyces candidum was the most efficient at producing SCP among the seven yeasts studied. The maximum cell dry weight (CDW) 6.79 g/L and protein content 39.39%, were obtained under the fermentation conditions of initial NH₄⁺-N concentration of 2000 mg/L and a C/N ratio of 6:1 with acetate as the pH regulator. The total CDW increased to 9.24 g/L after secondary fermentation. Metal elements had a little effect on the growth of G. candidum. The addition of sulfur not only promoted the synthesis of sulfur-containing amino acid cysteine but also increased protein content by promoting the synthesis of glutamic acid and glutamine.

Conclusions

Future experiments should focus more on achieving high-density cultivation and more efficient utilization of ammonia nitrogen in the biogas slurry.

How to cite: Zhou P, Zhang L, Ding H, et al. Optimization of culture conditions of screened Galactomyces candidum for the production of single cell protein from biogas slurry. Electron J Biotechnol 2022;55. https://doi.org/10.1016/j.ejbt.2021.11.006

Background

Gliomas are common malignant intracranial tumors. Efficacious targeted therapy against gliomas is lacking.

Results

GANT61 combined with the chemotherapy drug doxorubicin for treatment of glioma (LN-229) cells, and the effect of their combination, was tested. The molecular mechanism was explored by target prediction, along with functional analysis using the Gene Ontology (GO) database, enrichment analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, construction of protein–protein interaction (PPI) networks, and protein expression. Combination of GANT61 plus doxorubicin could inhibit the growth of LN-229 cells effectively. Wound-healing data and expression of migration proteins related to epithelial-to-mesenchymal transition showed that this combination could inhibit the migration of LN-229 cells. Sixty-one targets of drug and disease intersected. Functional analysis revealed negative regulation of apoptosis, positive regulation of cell proliferation, and other biological processes related to apoptosis and proliferation. Pathway-enrichment analysis showed drug combination to be related to the cyclic adenosine monophosphate signaling pathway, pathways in cancer, and Hedgehog signaling pathway. Measurement of expression of several proteins related to these pathways revealed expression of BIRC5, GLi1 and GLi2, MMP3 and MMP9 proteins to decrease, and expression of MDM2 and P53 proteins to decrease and increase, respectively.

Conclusions

This study provides a: (a) new direction for targeted therapy of gliomas; (b) theoretical basis for drug research and molecular-mechanism research on gliomas.

How to cite: Chen J, Zhang Q, Zhang G et al. Molecular mechanism of GANT61 combined with doxorubicin in the treatment of gliomas based on network pharmacology. Electron J Biotechnol 2022;55. https://doi.org/10.1016/j.ejbt.2021.11.001.