Diabetes mellitus is a multifactorial global health disorder that is rising at an alarming rate. Cardiovascular diseases, kidney damage and neuropathy are the main cause of high mortality rates among ...individuals with diabetes. One effective therapeutic approach for controlling hyperglycemia associated with type-2 diabetes is to target alpha-amylase and alpha-glucosidase, enzymes that catalyzes starch hydrolysis in the intestine. At present, approved inhibitors for these enzymes are restricted to acarbose, miglitol and voglibose. Although these inhibitors retard glucose absorption, undesirable gastrointestinal side effects impede their application. Therefore, research efforts continue to seek novel inhibitors with improved efficacy and minimal side effects. Natural products of plant origin have been a valuable source of therapeutic agents with lesser toxicity and side effects. The anti-diabetic potential through alpha-glucosidase inhibition of plant-derived molecules are summarized in this review. Eight molecules (Taxumariene F, Akebonoic acid, Morusin, Rhaponticin, Procyanidin A2, Alaternin, Mulberrofuran K and Psoralidin) were selected as promising drug candidates and their pharmacokinetic properties and toxicity were discussed where available.
Species that are currently listed under the genus
Brevibacillus
(formerly,
Bacillus brevis
cluster) have been a rich source of antimicrobial peptides for many decades. The first known peptide ...antibiotic, gramicidin, is presumed to be produced by a
Brevibacillus
sp. Members of the genus are widely spread in nature. They can be found in a variety of environments including intestinal tracts of animals, seawater, and soil. Some
Brevibacillus
strains have been used commercially as probiotics. Bioactive peptides produced by
Brevibacillus
spp. include antibacterial, antifungal and anti-invertebrate agents.
Brevibacillus
antimicrobial peptides are synthesized through ribosomal or nonribosomal pathway; these two groups can be further categorized based on specific structural features such as cyclization and presence of lipid chain. Some of the antimicrobial compounds produced by this genus share structural similarities that were overlooked previously. For example, the structural similarity between BT peptide, brevibacillin, and bogorol was revealed only recently. Here we review and classify
Brevibacillus
antimicrobial peptides and summarize their bioactivities and potential applications.
Testing SARS-CoV-2 viral loads in wastewater has recently emerged as a method of tracking the prevalence of the virus and an early-warning tool for predicting outbreaks in the future. This study ...reports SARS-CoV-2 viral load in wastewater influents and treated effluents of 11 wastewater treatment plants (WWTPs), as well as untreated wastewater from 38 various locations, in the United Arab Emirates (UAE) in May and June 2020. Composite samples collected over twenty-four hours were thermally deactivated for safety, followed by viral concentration using ultrafiltration, RNA extraction using commercially available kits, and viral quantification using RT-qPCR. Furthermore, estimates of the prevalence of SARS-CoV-2 infection in different regions were simulated using Monte Carlo. Results showed that the viral load in wastewater influents from these WWTPs ranged from 7.50E+02 to over 3.40E+04 viral gene copies/L with some plants having no detectable viral RNA by RT-qPCR. The virus was also detected in 85% of untreated wastewater samples taken from different locations across the country, with viral loads in positive samples ranging between 2.86E+02 and over 2.90E+04 gene copies/L. It was also observed that the precautionary measures implemented by the UAE government correlated with a drop in the measured viral load in wastewater samples, which were in line with the reduction of COVID-19 cases reported in the population. Importantly, none of the 11 WWTPs' effluents tested positive during the entire sampling period, indicating that the treatment technologies used in the UAE are efficient in degrading SARS-CoV-2, and confirming the safety of treated re-used water in the country. SARS-CoV-2 wastewater testing has the potential to aid in monitoring or predicting an outbreak location and can shed light on the extent viral spread at the community level.
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•First study to detect and quantify SARS-CoV-2 in wastewater in the UAE.•36 WWTP influents and 38 sewer/pumping station locations were monitored and tested.•Monte Carlo simulation estimates in 4 locations range between 2.21E+03 to 1.21E+04.•Wastewater monitoring could be used as an early tool for future outbreak detection.
It is already known that the process of photosynthesis depends on the quality and intensity of light. However, the influence of the new light sources recently used in horticulture, known as Light ...Emitting Diodes (LEDs), on this process is not yet fully understood. Chlorophyll a fluorescence measurement has been widely used as a rapid, reliable, and noninvasive tool to study the efficiency of the photosystem II (PSII) and to evaluate plant responses to various environmental factors, including light intensity and quality. In this work, we tested the responses of the tomato photosynthetic apparatus to different light spectral qualities. Our results showed that the best performance of the photosynthetic apparatus was observed under a mixture of red and blue light (R7:B3) or a mixture of red, green and blue light (R3:G2:B5). This was demonstrated by the increase in the effective photochemical quantum yield of PSII (YII), photochemical quenching (qP) and electron transport rate (ETR). On the other hand, the mixture of red and blue light with a high proportion of blue light led to an increase in non-photochemical quenching (NPQ). Our results can be used to improve the production of tomato plants under artificial light conditions. However, since we found that the responses of the photosynthetic apparatus of tomato plants to a particular light regime were cultivar-dependent and there was a weak correlation between the growth and photosynthetic parameters tested in this work, special attention should be paid in future research.
α-glucosidase inhibitors represent an important class of type 2 antidiabetic drugs and they act by lowering postprandial hyperglycemia. Today, only three synthetic inhibitors exist on the market, and ...there is a need for novel, natural and more efficient molecules exhibiting this activity. In this study, we investigated the ability of Tamarix nilotica ethanolic and aqueous shoot extracts, as well as methanolic fractions prepared from aqueous crude extracts to inhibit α-glucosidase. Both, 50% ethanol and aqueous extracts inhibited α-glucosidase in a concentration-dependent manner, with IC50 values of 12.5 μg/mL and 24.8 μg/mL, respectively. Importantly, α-glucosidase inhibitory activity observed in the T. nilotica crude extracts was considerably higher than pure acarbose (IC50 = 151.1 μg/mL), the most highly prescribed α-glucosidase inhibitor on the market. When T. nilotica crude extracts were fractionated using methanol, enhanced α-glucosidase inhibitory activity was observed in general, with the highest observed α-glucosidase inhibitory activity in the 30% methanol fraction (IC50 = 5.21 μg/mL). Kinetic studies further revealed a competitive reversible mechanism of inhibition by the plant extract. The phytochemical profiles of 50% ethanol extracts, aqueous extracts, and the methanolic fractions were investigated and compared using a metabolomics approach. Statistical analysis revealed significant differences in the contents of the crude extracts and fractions and potentially identified the molecules that were most responsible for these observed variations. Higher α-glucosidase inhibitory activity was associated with an enrichment of terpenoids, fatty acids, and flavonoids. Among the identified molecules, active compounds with known α-glucosidase inhibitory activity were detected, including unsaturated fatty acids, triterpenoids, and flavonoid glycosides. These results put forward T. nilotica as a therapeutic plant for type 2 diabetes and a source of α-glucosidase inhibitors.
Biogas – a renewable energy source encompassing primarily CO2/CH4 mixture, can fuel vehicles if it is properly purified. Recently, cryogenic biogas upgrading (CO2 Liquefaction) witnesses a ...significant progress as a promising purification technique; however, the obstacle hinders its implementation is CO2 freeze-out causing crucial issues as blockage pipes. Therefore, in-depth analysis for tackling this barrier is performed in this work through optimizing operating conditions of a typical low-temperature CO2/CH4 distillation process. Optimization is conducted towards avoiding frosting and lowering energy consumption via varying distillation pressure, temperature, reflux ratio and number of trays, biogas feed composition, and CH4 purity generated. We found that, without CO2 freeze-out, obtaining CH4 purity of 97.12% (mol) – besides a valuable by-product (liquid CO2, 99.92% purity) – is achievable using two columns through adjusting some key parameters. The results divulge that raising distillation pressure and reflux ratio significantly mitigates frosting danger. Moreover, for energy-efficient process, using one column is the most efficient way to produce methane purity below 96% whereas two columns for higher purities. Also, feeding cryogenic process with high-concentration CO2 biogas alleviates energy penalty, ameliorating its competitiveness against traditional technologies. With these new findings, cryogenic platforms can be applicable, competitive biogas upgrading approach.
•Cryogenic distillation model is introduced for upgrading biogas (CO2/CH4 separation).•Main question is addressed: under which conditions the process can avoid CO2 frost.•Increasing distillation operating pressure and reflux ratio mitigates frosting risk.•Using one column is more efficient below 96% purity while two columns for higher one.•Cryogenic upgrading is more energy-efficient for biogas with high-concentration CO2.
In recent years, much effort has been devoted to understanding the response of plants to various light sources, largely due to advances in industry light-emitting diodes (LEDs). In this study, the ...effect of different light modes on rocket (Eruca sativa. Mill.) photosynthetic performance and other physiological traits was evaluated using an orthogonal design based on a combination between light intensity, quality, and photoperiod factors. Some morphological and biochemical parameters and photosynthetic efficiency of the plants were analyzed. Plants grew in a closed chamber where three light intensities (160, 190, and 220 μmol m-2 s-1) provided by LEDs with a combination of different ratios of red, green, and blue (R:G:B- 7:0:3, 3:0:7, and 5:2:3) and three different photoperiods (light/dark -10/14 h, 12/12 h, and 14/10 h) were used and compared with white fluorescent light (control). This experimental setup allowed us to study the effect of 9 light modes (LM) compared to white light. The analyzes performed showed that the highest levels of chlorophyll a, chlorophyll b, and carotenoids occurred under LM4, LM3, and LM1, respectively. Chlorophyll a fluorescence measurement showed that the best effective quantum yield of PSII photochemistry Y(II), non-photochemical quenching (NPQ), photochemical quenching coefficient (qP), and electron transport ratio (ETR) were obtained under LM2. The data showed that the application of R7:G0:B3 light mode with a shorter photoperiod than 14/10 h (light/dark), regardless of the light intensity used, resulted in a significant increase in growth as well as higher photosynthetic capacity of rocket plants. Since, a clear correlation between the studied traits under the applied light modes was not found, more features should be studied in future experiments.
The coronavirus disease 2019 (COVID-19) pandemic is caused by a new coronavirus family member, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is linked with many disease ...manifestations in multiple organ systems on top of pulmonary manifestations. COVID-19 is also accompanied by several cardiovascular pathologies including myocarditis, acute myocardial infarction, stress cardiomyopathy, arterial and venous thromboembolism, pericarditis, and arrhythmias. The pathophysiological mechanisms explaining these clinical symptoms are multifactorial including systemic inflammation (cytokine storm), coagulopathy, direct viral invasion through angiotensin-converting enzyme 2, hypoxemia, electrolyte imbalance, and fever. Several case reports have shown the development of an unusual cardiovascular event after receiving SARS-CoV-2 vaccines. The current article aimed to review cardiovascular involvement in the COVID-19 pandemic with respect to clinical features, pathogenesis, long-term effects, and the adverse effects of treatments and vaccines based on the latest evidence.
Biofilms are intricate multicellular structures created by microorganisms on living (biotic) or nonliving (abiotic) surfaces. Medically, biofilms often lead to persistent infections, increased ...antibiotic resistance, and recurrence of infections. In this review, we highlighted the clinical problem associated with biofilm infections and focused on current and emerging antibiofilm strategies. These strategies are often directed at disrupting quorum sensing, which is crucial for biofilm formation, preventing bacterial adhesion to surfaces, impeding bacterial aggregation in viscous mucus layers, degrading the extracellular polymeric matrix, and developing nanoparticle-based antimicrobial drug complexes which target persistent cells within the biofilm core. It is important to acknowledge, however, that the use of antibiofilm agents faces obstacles, such as limited effectiveness in vivo, potential cytotoxicity to host cells, and propensity to elicit resistance in targeted biofilm-forming microbes. Emerging next generation antibiofilm strategies, which rely on multipronged approaches, were highlighted, and these benefit from current advances in nanotechnology, synthetic biology, and antimicrobial drug discovery. The assessment of current antibiofilm mitigation approaches, as presented here, could guide future initiatives toward innovative antibiofilm therapeutic strategies. Enhancing the efficacy and specificity of some emerging antibiofilm strategies via careful investigations, under conditions that closely mimic biofilm characteristics within the human body, could bridge the gap between laboratory research and practical application.
Brevibacillin is a newly-discovered antimicrobial lipopeptide produced by Brevibacillus laterosporus OSY-I1. It is active against Gram-positive bacteria, including antibiotic resistant strains. This ...research was initiated to investigate the mechanism of action of brevibacillin against an indicator strain, Staphylococcus aureus ATCC 6538. Results of the study proved that brevibacillin binds to lipoteichoic acid (LTA) on cell wall before interacting with cell membrane. Additionally, brevibacillin disrupts S. aureus cytoplasmic membrane by increasing its permeability, depolarization and potassium leakage. Therefore, cytoplasmic membrane serves as a major target for brevibacillin. Despite the presence of multiple sites on S. aureus cell envelope, scanning electron microscope observation didn’t reveal evidence of cell lysis or any morphological defects in cells treated with brevibacillin. Based on the results of this study, we propose that the electrostatic interaction between the cationic brevibacillin and the anionic LTA helped the accumulation of the antimicrobial agent at cell surface; this was followed by translocation of the lipopeptide to the cytoplasmic membrane and disrupting its vital functions.
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