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Abstractβ-Glucanase has received great attention in recent years regarding their potential biotechnological applications and antifungal activities. Herein, the specific objectives of the present study were to purify, characterize and immobilize β-glucanase from Aspergillus niger using covalent binding and cross linking techniques. The evaluation of β-glucanase in hydrolysis of different lignocellulosic wastes with subsequent bioethanol production and its capability in biocontrol of pathogenic fungi was investigated. Upon nutritional bioprocessing, β-glucanase production from A. niger EG-RE (MW390925.1) preferred ammonium nitrate and CMC as the best nitrogen and carbon sources, respectively. The soluble enzyme was purified by (NH4)2SO4, DEAE-Cellulose and Sephadex G200 with 10.33-fold and specific activity of 379.1 U/mg protein. Tyrosyl, sulfhydryl, tryptophanyl and arginyl were essential residues for enzyme catalysis. The purified β-glucanase was immobilized on carrageenan and chitosan with appreciable yield. However, the cross-linked enzyme exhibited superior activity along with remarkable improved thermostability and operational stability. Remarkably, the application of the above biocatalyst proved to be a promising candidate in liberating the associate lignocellulosic reducing sugars, which was utilized for ethanol production by Saccharomyces cerevisiae. The purified β-glucanase revealed an inhibitory effect on the growth of two tested phytopathogens Fusarium oxysporum and Penicillium digitatum.

AbstractThe present paper experimentally explores the influence of the fiber hybridization and layering sequence on crashworthiness behavior and deformation history of polymer/metal thin-walled pipes. Jute (J)/glass (G) reinforced epoxy over wrapped aluminum (Al) pipes were prepared via hand wet wrapping then subjected to axial quasi-static compressive loads. The load versus displacement plots and crashing indicators, i.e. peak crushing load ($${\mathrm{F}}_{\mathrm{ip}}$$ F ip ), mean crushing load ($${\mathrm{F}}_{\mathrm{m}}$$ F m ), total energy absorption ($$\mathrm{U})$$ U ) , specific energy absorption $$\left(\mathrm{SEA}\right)$$ SEA , and crush force efficiency $$\left(\mathrm{CFE}\right)$$ CFE were determined. Experimental results revealed that the maximum $$\left(\mathrm{SEA}\right)$$ SEA was recorded for Al/2J/4G/2J pipe with a value of about 42.92 kJ/g, with an enhancement of 20.56% in $$\left(\mathrm{SEA}\right)$$ SEA compared with pure Al-pipes. Al/2J/4G/2J specimens display the maximum ($$\mathrm{U})$$ U ) , $$\left(\mathrm{SEA}\right)$$ SEA , and $$\left(\mathrm{CFE}\right)$$ CFE and could be employed as energy absorbing members in automobiles.

AbstractThe Fram Strait is the only deep gateway between the Arctic Ocean and the Nordic Seas and thus is a key area to study past changes in ocean circulation and the marine carbon cycle. Here, we study deep ocean temperature, δ18O, carbonate chemistry (i.e., carbonate ion concentration [CO32−]), and nutrient content in the Fram Strait during the late glacial (35,000–19,000 years BP) and the Holocene based on benthic foraminiferal geochemistry and carbon cycle modeling. Our results indicate a thickening of Atlantic water penetrating into the northern Nordic Seas, forming a subsurface Atlantic intermediate water layer reaching to at least ∼2,600 m water depth during most of the late glacial period. The recirculating Atlantic layer was characterized by relatively high [CO32−] and low δ13C during the late glacial, and provides evidence for a Nordic Seas source to the glacial North Atlantic intermediate water flowing at 2,000–3,000 m water depth, most likely via the Denmark Strait. In addition, we discuss evidence for enhanced terrestrial carbon input to the Nordic Seas at ∼23.5 ka. Comparing our δ13C and qualitative [CO32−] records with results of carbon cycle box modeling suggests that the total terrestrial CO2 release during this carbon input event was low, slow, or directly to the atmosphere.

The geometrical efficiency of a source-to-detector configuration is considered to be necessary in the calculation of the full energy peak efficiency, especially for NaI(Tl) and HPGe gamma-ray spectroscopy detectors. The geometrical efficiency depends on the solid angle subtended by the radioactive sources and the detector surfaces. The present work is basically concerned to establish a new mathematical approach for calculating the solid angle and geometrical efficiency, based on conversion of the geometrical solid angle of a non-axial radioactive point source with respect to a circular surface of the detector to a new equivalent geometry. The equivalent geometry consists of an axial radioactive point source with respect to an arbitrary elliptical surface that lies between the radioactive point source and the circular surface of the detector. This expression was extended to include coaxial radioactive circular disk source. The results were compared with a number of published data to explain how significant this work is in the efficiency calibration procedure for the γ-ray detection systems, especially in case of using isotropic radiating γ-ray sources in the form of point and disk shapes.

Cyclophosphamide (CP) is an anticancer drug that causes infertility disorders. This study was designed to evaluate a nanoformulation of chitosan with an ethanolic extract from Spirulina platensis in terms of its protection against cyclophosphamide-induced ovarian toxicity. Nine groups of female Wistar rats were randomly assigned as follows: 1: control vehicle, 2: chitosan polymer, 3: telmisartan, 4: Spirulina platensis extract, 5: nanoformulation of the Spirulina platensis, and 6: single injection of CP; groups 7, 8, and 9 received the same treatments as those used in groups 3, 4, and 5, respectively, with a single dose of CP (200 mg/kg, I.P). The results displayed that the CP treatment decreased estradiol, progesterone, anti-mullerian hormone, and GSH content, and it downregulated PPAR-γ, Nrf-2, and HO-1 gene expression. In addition, the CP treatment caused an increase in the FSH, LH, and MDA levels. In the same manner, the protein expression of caspase-3, NF-kB, and TNF-α was upregulated in response to the CP treatment, while PPAR-γ was downregulated in comparison with the control. The rats treated with SPNPs exhibited a substantial reduction in the detrimental effects of oxidative stress and inflammation of the ovarian tissue. This study’s conclusions showed that SPNPs counteracted the effects of CP, preventing the death of ovarian follicles and restoring the gonadotropin hormone balance and normal ovarian histological appearance.

2,3-Butanediol (2,3-BDO) has gained much attention due to its bulk chemical uses in numerous applications such as the production of pharmaceuticals, cosmetics, synthetic rubber, inks, resins, perfumes, foodstuffs, fuel additives, and aviation fuel.

We have investigated in the current study the possible protective effects of two carnitine esters known to have powerful anti-oxidant potential namely, propionyl L-carnitine (PLC) and acetyl L-carnitine (AC) against alcohol-induced gastric lesions in rats. Both drugs were administered as a single oral dose of 200 mg kg(-1) body weight 1h before alcohol intake. Both carnitine esters could protect the gastric mucosa against the injurious effect of absolute alcohol and promote ulcer healing as evidenced from the ulcer index (UI) values. Propionyl L-carnitine prevented alcohol-induced increase in thiobarbituric acid-reactive substances (TBARS), an index of lipid peroxidation. The propionyl carnitine ester also increased the gastric content of reduced glutathione (GSH), besides it increased the enzymatic activities of gastric superoxide dismutase (SOD) and glutathione-S-transferase (GST). Likewise, AC did protect against the ulcerating effect of alcohol and mitigate most of the biochemical adverse effects induced by alcohol in gastric mucosa, but to a lesser extent than PLC. Neither PLC nor AC did affect catalase activity in gastric tissue. Based on these observations, one could conclude that carnitine esters, particularly PLC could partly protect gastric mucosa from alcohol-induced acute mucosal injury, and these gastroprotective effects might be probably induced, at least partly, through anti-oxidant mechanisms.