Regarding the significance of SARS-CoV-2, scientists have shown considerable interest in developing effective drugs. Inhibitors for PLpro are the primary strategies for locating suitable COVID-19 ...drugs. Natural compounds comprise the majority of COVID-19 drugs. Due to limitations on the safety of clinical trials in cases of COVID, computational methods are typically utilized for inhibition studies. Whereas papain is highly similar to PLpro and is entirely safe, the current study aimed to examine several plant secondary metabolites to identify the most effective papain inhibitor and validate the results using molecular dynamics and docking. This simulation was conducted identically for PLpro and the optimal inhibitor. The results indicated that the experimental results are comparable to those obtained In-Silico, and the inhibition effects of Chlorogenic acid (CGA) on papain attained in the experiment were validated (IC
50
=0.54 mM). CGA as an inhibitor was located in the active site of PLpro and papain (total energy −2009410 and −456069 kJ/mol, respectively) at the desired location and distance. The study revealed that CGA and its derivatives are effective PLpro inhibitors against SARS-CoV-2.
Communicated by Ramaswamy H. Sarma
In this study, four conventional and a newly proposed method of wavelet-exponential smoothing (WES) - with two presented scenarios (WES
1
and WES
2
) – are employed to estimate daily and monthly ...suspended sediment load (SSL) in two rivers (Lighvanchai river in Iran and Upper Rio Grande in the USA), which have different hydro-geomorphological characteristics of the related watersheds. In the proposed WES method, first, wavelet transform (WT) is applied to the original observed time series to decompose them into approximation and detailed subseries to separate different components of time series. For the first scenario (WES
1
), only two time series, i.e., an approximation and a detail time series are utilized as inputs of model, whereas for the second scenario (WES
2
), all subseries are separately fed into different exponential smoothing (ES) models. The results revealed that for both rivers, the proposed WES
2
and wavelet based artificial neural network (WANN) models could lead to superior performance in comparison to the autoregressive integrated moving average (ARIMA), seasonal ARIMA (SARIMA), ES ad-hoc and artificial neural network (ANN). The WES
2
method could enhance the overall performance of SSL forecasting both in daily and monthly modeling of the case studies regarding Nash-Sutcliffe (E) efficiency criteria, respectively up to 13%, 42% and 87%, 116% in daily and monthly scales for SSL modeling of the Lighvanchai and Upper Rio Grande Rivers. As a result, combining WT with ES method and ANN led to more accurate modeling.
Demands for peroxidases (POX)s with diverse physicochemical properties have steadily grown as more applications of POXs are demonstrated. Plants are among the best sources of versatile POXs, and ...plant biotechnology, as an agricultural hassle-free technology, promises to circumvent the limitations of natural resource exploitation and to address the demands. Following this trend, it was shown that POX production steadily increased during the 31-day subculture of Alkanna frigida (from Boraginaceae) callus on Murashige-Skoog medium containing 2,4-dichlorophenoxyacetic acid (10−6 M) and kinetin (10−5 M). The purified cationic enzyme (POXalf) maintained its optimal activity over pH 4–7 for 2 years. It was resistant to H2O2 high concentrations (IC50 = 543.7 mM) and showed high specific activity in the reaction with phenol (4320.5 AU mg−1 > 20-fold of HRP AU). Furthermore, the specificity constant ratio of guaiacol to phenol indicated a 100 times faster reaction of POXalf with guaiacol. However, in contrast to HRP, it had little effect on diazo derivatives of aniline and meta-diaminobenzene. Based on the resulting primary structure from the tandem mass analysis, the POXalf 3D structure was constructed via homology modelling. Despite the high topological similarity between the HRP and POXalf structures, there were important differences between the active site pockets that could explain the observed differences in the corresponding substrate spectra and the specific activities. Considering the dynamics of POXalf production, its inactivity towards IAA and its high affinity for guaiacol, POXalf may have associated roles with A. frigida cell wall construction and monolignol metabolism.
A novel cationic peroxidase was obtained from the cell culture of Alkanna figida. Despite the high similary between the 3-D structures of HRP-C and this peroxidase, there are important structural differences between the active site pockets that can explain their different physicochemical features. Display omitted
•Production of a novel peroxidase (POXalf) by cell culture of Alkanna frigida.•Purified POXalf had wide optimal pH, high H2O2 tolerance & functional stability.•POXalf specific activities with phenol & guaiacol were much higher than HRP.•POXalf 3D structure obtained via mass analysis, cDNA synthesis & homology modelling.•Active site pockets differences were shown to explain observed differences with HRP.
Density functional theory (DFT) calculations were employed to investigate the effects of adsorption of toxic carbon monoxide (CO) and nitrogen monoxide (NO) molecules on heterogeneous C
16
Zn
8
O
8
...nanocage. A detailed analysis of the energetic, geometry, and electronic structure of various CO and NO adsorptions on the cluster surface was performed. It has been shown that CO molecule was adsorbed on the surface of the cluster resulting in more stable complex system, while NO molecule adsorption led to less stable system. These processes also changed the electronic properties of the cluster by reducing the HOMO/LUMO energy gap after adsorption process. Since this phenomenon led to an increment in the electrical conductivity of the cluster at a definite temperature, the C
16
Zn
8
O
8
was transformed to a stronger semiconductor substance upon the CO and NO adsorption. We believe that this research may be helpful in the several fields study such as sensor and catalyst investigation.
Extensive applications of peroxidase (POX) have raised the global market demand at a considerable rate during the forecast period of 2020–2025. Nonetheless, the large-scale POX preparation still ...relies on the extraction from agricultural products, while there is an accumulative driving force toward employing biotechnological processes with agricultural hassle free identity. Consequently, a novel heme peroxidase was purified to homogeneity (MW of 40 kD) from the callus culture of basil in darkness on Murashige-Skoog medium supplemented by 2,4-dichlorophenoxyacetic acid (10
–6
M) and kinetin (10
–5
M). The highest activity of the purified peroxidase (ObPOX) was observed in Tris-base buffer at pH 7.5 and 80 °C. ObPOX showed high stability over pH(s) 5 to 7.5 and temperatures of 15 to 60 °C. ObPOX specific activity was 1245.142 AU mg
−1
in the presence of phenol, 4 times higher than that of HRP. ObPOX showed moderate affinity for guaiacol (K
m
= 21.5 mM), but obtained an exceptionally high specificity constant (k
cat
/K
m
= 66,743.7 s
−1
M
−1
) for GASA (4-(4-Hydroxy-3-methoxyphenyl) azo-benzenesulfonic acid), the introduced substrate for determination of blood sugar. Applying ObPOX instead of HRP in glucose measurements of the real samples improved the regression constant of the correlation diagram between the tests and the lab results from 0.958 to 0.981. Physicochemical properties of ObPOX as well as the growth rate of basil callus (5.04 g L
−1
per day) and the yield of ObPOX production (35 mg per 100 g dry biomass per subculture) designates
O. basilicum
cell culture for large-scale production of a robust peroxidase.
Key message
In this paper, the solid cell culture of basil, a palatable herb with proven antioxidant capacity, was introduced for production of a novel peroxidase with a performance much better than HRP. The enzymatic capacity of this peroxidase can be exploited for bioassay purposes.
Iranian copper coins of the Qaj ar era-all described by the word falus-have a great variety of designs, weights, and sizes. These coins sometimes also include letters and phrases that are ...undeciphered to date. This article uses siyāq script to read some of these mystery notations for the first time. The multiple fascinating examples of siyāq numbers found thereby on Qajar coins and countermarks show that, contrary to former belief, some copper coins of this era had specific face values written on them in the siyāq script. This research uses these copper coins to take a small step toward a better understanding of the monetary system of the Qajar era by introducing several denominations never reported before. Finally, as siyāq script had never been discovered on coins, this new possibility now allows numismatists and scholars to revisit and correct former interpretations or to introduce and decipher new coins in the future.
There is an increasing need for accurate and inexpensive glucometers as the world moves toward personalized medicine. Among the existing technologies, photometric based devices are more desired due ...to the cost-effectiveness, ease-of-use and the potential to be adopted in the smart-phone technology for remote sensing and self-monitoring purposes. However, the accuracy, precision, and reproducibility of the results of these devices are heavily dependent on the details of the chosen glucose measuring method. Considering the delicate problems with the current spectrophotometric methods, a new method was developed for more precise, accurate, and fast measurement of blood glucose via the coupled reactions of glucose oxidase and peroxidase using 4-(4-Hydroxy-3-methoxyphenyl) azo-benzenesulfonic acid (GASA) as the substrate. Stability of GASA and its oxidized products along with its direct and fast consumption by peroxidase, made it possible to determine blood glucose concentration in <20 s with high reproducibility. The low detection limit of GASA method (0.36 mg dL−1) with a linear range from 0.36 to 399.6 mg.dL−1 also allowed determination of salivary glucose concentration (SGC). As compared with the blood samples, the SGC results were more dispersed, especially for the diabetic participants, assumingly due to the diverse nature of salivary samples. However, a good correlation coefficient of 0.81 for non-diabetic individuals showed that it is accurate enough to recognize non-diabetic from diabetic condition. Results of this study disclose the potential application of GASA method as a reliable alternative for the current spectrophotometric methods with the ability to be adopted in miniaturized glucometers.
Display omitted
•A guaiacol diazo derivative (GASA) was used as substrate in joint-enzymatic assay of glucose•Stability and spectrophotometric properties of GASA and its oxidation products allowed accurate blood sugar determination•Sensitive, fast and linear spectrophotometric responses of GASA also allowed accurate salivary glucose measurement•Direct tracking of GASA oxidation, free of spectral interferences, gives precise glucose concentration•GASA method advantages give it the merit to be used in photometric-based personal glucometers
This study describes the synthesis of molecularly imprinted polymers (MIPs) using bovine albumin as a template, 2-VP as a functional monomer, EGDMA as a cross-linker and AIBN as an initiator by ...radical polymerization. Non-imprinted polymers (NIPs) were prepared and treated with the same method, but in the absence of bovine albumin. The synthesized MIPs and NIPs were characterized on the basis of FTIR, TGA and DTA. An adsorption process (solid phase extraction, SPE) for the removal of bovine albumin using the fabricated MIPs and NIPs was evaluated under various conditions. Effective parameters on bovine albumin retention for example, pH, flow rate, nature of the eluent, the ionic strength, selectivity coefficient, and retention capacity were studied. Competition test implicates that the MIP adsorbents have the strongest specific retention and enrichment for bovine albumin respect to NIPs. The maximum adsorption of bovine albumin by the fabricated MIPs was 24mg/g. The calibration curves were linear in the range of 20–200mg/L of bovine albumin. The limit of detection (LOD), the calibration sensitivity, the relative standard deviation (RSD) and preconcentration factor under optimal experimental conditions were 2.44 and 25, respectively. The extraction of bovine albumin from blood serum, urine, whey and milk samples had a selectivity and enrichment property. In the actual experiment for real samples, recovery of ~80% was achieved.
With respect to the different hydrological responses of catchments, even the adjacent ones, in mountainous regions, there are a great number of motivations for classifying them into homogeneous ...clusters. These motivations include prediction in ungauged basins (PUB), model parameterization, understanding the potential impact of environmental changes, transferring information from gauged catchments to the ungauged ones. The present study investigated the similarity of catchments through the hydro-climatological pure time-series of a 14-year period from 2001 to 2015. Data sets encompass more than 13,000 month-station streamflow, rainfall, and temperature data obtained from 27 catchments in Utah State as one of the eight mountainous states of the USA. The identification, analysis, and interpretation of homogeneous catchments were investigated by applying the four approaches of clustering, K-means, Ward, and SOM (Self-Organized Map) and a newly proposed Wavelet-Entropy-based (WE-SOM) clustering method. By using two clustering evaluation criteria, 3, 5, and 6 clusters were determined as the best numbers of clusters, depending on the method employed, where each cluster represents different hydro-climatological behaviors. Despite the absence of geographic characteristics in input data matrix, the results indicated a regionalization in agreement with topographic characteristics. Considering the dependency of the hydrological behavior of catchments on the physiographic field aspects and characteristics, WE-SOM method demonstrated a more acceptable performance, compared to the other three conventional clustering methods, by providing more clusters. WE-SOM appears to be a promising approach in catchment clustering. It preserves the topological structure of data which can, as a result, be proofed in a greater number of clusters by dividing data into higher numbers of distinct clusters with similar altitudes of catchments in each cluster. The results showed the aptitude of wavelets to quantify the time-based variability of temperature, rainfall and streamflow, in the way contributing to the regionalization of diverse catchments.
The cellulase component ratio affects the bioethanol yield in the bioethanol process. A method to increase the enzymatic degradation efficiency of cellulose is by preparing a cocktail of involved ...enzymes. The aim of this study is cocktail preparation and optimization which will reduce the cost of bioethanol process hydrolysis. Moreover, best enzyme composition and ratio depends on the substrate and type of the performed pretreatment. In the present study, response surface methodology (RSM) was used to optimize the ratio of three cellulase involved enzymes, including Exo-1,4-β-D-glucanases II (CBHII), Endo-1,4-β-D-glucanases II (EGII) and 1,4-β-D-glucosidases I (BGI), for degradation of pretreated bagasse. A cellulase activity based on the glycan residue formation was monitored using high performance Liquid Chromatography-Mass Spectrometry (LC-ESI/MS). In addition to cocktail production, the influential parameters affecting the process were studied and the best rate of enzymatic cocktail was adjusted to 1:5:1 (mg/g bagasse) EGII, CBHII and BGLI, respectively. Results revealed that the highest rates of glucose production were 20.5 and 41.4 mg/g within 24 and 48 h, respectively.
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