Sustainable sorbitol dehydration to isosorbide using solid acid catalysts: transition from batch reactor to continuous flow system

Isosorbide is one of the most interesting cellulosic-derived molecules with great potential to be implemented in wide range of products that shaping our daily life. This minireview describes the recent developments in the production of isosorbide from sorbitol in batch and continuous flow systems under hydrothermal conditions using solid acid catalysts. Moreover, we are summarizing the current hurdles and challenges that facing the synthesis of isosorbide from cellulosic biomass in continuous flow process using solid acid catalysts, as well as the scaling up of this process into pilot level, which will lead to an established industrial process with high sustainability metrics

Controlled lignosulfonate depolymerization via solvothermal fragmentation coupled with catalytic hydrogenolysis/hydrogenation in continuous flow reactor

Sodium lignosulfonate (LS) was valorized to low molecular weight (Mw) fractions by combining solvothermal (SF) and catalytic hydrogenolysis/hydrogenation fragmentation (SHF) in continuous flow system. This achieved in either alcohol/water (EtOH2O or MeOH/H2O) as a solvent and Ni on nitrogen-doped carbon as a catalyst. The tunability according to temperature of both SF and catalytic SHF of LS has been separately investigated at 150°C, 200°C and 250°C. In SF, the minimal Mw was 2994 g mol-1 at 250°C with a dispersity (Đ) of 5.3 using MeOH/H2O. In catalytic SHF using MeOH/water, extremely low Mw was found (433 mg gLS-1) with Đ of 1.2 combined with 34 mg gLS-1. The monomer yield was improved to 42 mg gLS-1 using dual catalytic beds. These results is a direct evident that lignin is an unstable polymer at elevated temperature and could be efficiently deconstructed in hydrothermal conditions with and without catalyst

Comparison Between Deterministic and Stochastic Model for Interaction (COVID-19) With Host Cells in Humans

في هذا البحث ,تم اقتراح النموذج الحتمي والعشوائي لدراسة تفاعل فيروس كورونا (كوفيد -19) مع الخلايا المضيفة داخل جسم الانسان  .في النموذج الحتمي تحدد قيمة رقم الاستنساخ الأساسي  استمرار أو انقراض كوفيد-19.اذا كان رقم الاستنساخ الأساسي أقل من واحد   فأن خلية واحدة مصابة ستصيب أقل من خلية واحدة ,وهذا يعني ان الشخص الذي يحمل فيروس كورونا قد تم شفاؤه. اذا كان رقم الاستنساخ الاساسي اكبر من واحد  ستكون الخلية المصابة قادرة على القضاء على مجموعة الخلايا المستهدفة .في النموذج التصادفي , نثبت أنه اذا كانت المعلمات التصادفية  كبيرة بدرجة كافية فأن هذه المعلمات التصادفية تعطينا  الانقراض النهائي للمرض على الرغم من رقم الاستنساخ الاساسي اكبر من واحد . وقد تم أثبات هذه الحقائق أيضا من خلال المحاكاة الحاسوبية.In this paper, the deterministic and the stochastic models are proposed to study the interaction of the Coronavirus (COVID-19) with host cells inside the human body. In the deterministic model, the value of the basic reproduction number   determines the persistence or extinction of the COVID-19. If   , one infected cell will transmit the virus to less than one cell, as a result,  the person carrying the Coronavirus will get rid of the disease .If   the infected cell  will be able to infect  all  cells that contain ACE receptors. The stochastic model proves that if  are sufficiently large then maybe  give  us ultimate disease extinction although ,  and this  facts also proved by computer simulation

INVESTIGATION OF Helicobacter pylori VIRULENCE GENOTYPE IN GASTRIC BIOPSIES BY PCR

  Background: Helicobacter pylori infections has been associated with the genetic diversity of their virulence factors, the virulence genotypes are valuable as molecular marker in the diagnosis of patients with bacterial infections . Our main objective was to analyze the frequency and allelic genotype of vacA , cagA also investigate another virulence genes of H. pylori. Methods: 75 biopsies of  patients with gastritis and peptic ulcer diseases were selected to investigate the presences of H. pylori and collected from them antrum biopsies, then  genomic DNA was extracted from  antrum biopsies using genomic DNA kit .Subsequently, the virulence genes of H. pylori   were amplified using specific primers including vacA , cagA, cagE and oipA and iceA by PCR in 49 cases that positive to 16SrRNA which previously investigated. Results: A high prevalence of genes cagA  (28.6%), vacAs1bm2 (56.8%), iceA2 (30.6%)  and oipA  (42.9%) was found, while  vacA s2m1  and iceA1 genotypes  was not found in our study.  There was significant correlation between the presence of cagA and cagE genotypes (p = 0.02), suggesting that these two genes almost used together as cag PAI integrity marker. The  presence of cagA gene was significantly associated with peptic ulceration (p ≤ 0.001), whereas different vacA genotypes or iceA2 genotype were no statistically significant  with clinical outcome.  Patients with peptic ulcer disease more likely to have oipA gene (61.9% ) than those with gastritis (38.1%), P = 0.037, also the presence oipA gene was statistically significant with presence iceA2. Conclusion : Most H. pylori genotypes which associated with peptic ulcer and gastritis were moderate virulent strains. Â

Continuous-flow production of isosorbide from aqueous-cellulosic derivable feed over sustainable heterogeneous catalysts

Continuous-flow sorbitol dehydration in liquid water was performed on β zeolite (Si/Al molar ratio = 75) with conversion of 94 and 83 mol % isosorbide yield. This efficiency is due to the three-dimension pore architecture, high specific surface area (520 m2 g–1), and Brønsted acid sites of 69 μmol g–1. The pore size of β zeolite (6.6 × 6.7 Å2) is slightly larger than the cross section of sorbitol and isosorbide and enables an efficient diffusion of the reactant and product to/from the pores. Operation in continuous flow allows rapid dehydration of sorbitol to 1,4-sorbitan, after which the latter got converted to isosorbide. The high yield of isosorbide is attributed to the continuous removal of the formed products from the catalyst surface. Finally, direct isosorbide production from aqueous glucose solution via hydrogenation on Ni catalyst supported on nitrogen-doped carbon, followed by dehydration of the formed sorbitol to isosorbide, was pioneered

Effect of consumption supplemented strained yoghurt with vegetables on reducing weight of obese women samples

Obesity during adulthood is a public health problem in modern society, and increasingly universal disease that is turning into an epidemic one. The main cause of the excessive deposition of fat is the destruction of the systems controlling the expenditure of energy. Pathological increase of mass fat leads to disorders of the body, and lipid-carbohydrate parameters, raise the development of vascular diseases and increases the risk of morbidity and mortality. A substantial body of data has elicited over the last five years to show  that dairy foods especially low-fat yogurt modulate weight loss and has some unique properties that may enhance its role in maintenance of healthy weight. Regular physical activity is an important as what we eat for losing, maintains weight and keeping our heart healthy. Being active helps burn calories, tone our muscles and control our appetite.  The aim of this study is to demonstrate the impact of diet which was restricted in its energy by consuming concentrated yogurt daily and physical activity changes in the body weight, body mass index, and in the parameters lipid- cholesterol of women's adulthood.  Low-fat yogurt, restricted energy consumption with at least three times exercises weekly inversely associated with body weight, BMI, and WC (all p< 0.05). Also, consumption of low-fat yogurt and exercising daily was associated inversely with blood glucose, cholesterol and lipid parameter (all p< 0.05). Within a sample of obese adults women, consumption of low-fat dairy product and increases the physical activity with restricted energy ingestion  was associated with more favorable body composition. Keywords: Obesity, diet-yogurt, physical activity,  BMI-blood lipid, parameter

FEBUXOSTAT MODULATES OXIDATIVE AND APOPTOTIC PATHWAYS IN ACUTE DOXORUBICIN‑INDUCED CARDIOTOXICITY: AN EXPERIMENTAL ANIMAL MODEL STUDY

Objectives: Doxorubicin is one of the most important and powerful anticancer drugs, the most pronounced limitation for its use is toxicity on normal cells. Mechanism of doxorubicin-induced cardiotoxicity (DIC) is multifactorial and complex, including direct DNA damage, formation of free radicals, interference with DNA repair, and activation of immune reactions. Febuxostat is a non-purine-selective xanthine oxidase inhibitor decrease the production of uric acid. The aim of the present study was to evaluate the influence of febuxostat on doxorubicin-induced acute cardiotoxicity in rats regarding oxidative stress and antiapoptotic effects. Methods: A total of 30 Sprague Dawley male rats were used which subdivided into three groups: Group I (negative control group) received normal saline for 10 days, Group II (positive control group) received normal saline plus single dose of doxorubicin (15 mg/kg, IP), and Group III (treated group) received febuxostat (10 mg/kg, po), for 10 successive days plus single dose of doxorubicin (15 mg/kg, I.P.). Serum brain natriuretic peptide (BNP), cardiac troponin I (cTn-I), caspase-3, glutathione peroxidase (GSH-Px), lipid peroxidase (LPO), malondialdehyde (MDA), and tumor necrosis factor alpha were estimated by ELISA kit method. Results: Febuxostat administration before doxorubicin led to significant decrease on cardiac troponin, caspase-3, and elevation in GSH-Px levels significantly p<0.05. While the effects of febuxostat on BNP, LPO, MDA, tumor necrosis-alpha were insignificant p>0.05 compare to doxorubicin. Conclusion: Febuxostat attenuates DIC through modulation of antioxidant, anti-inflammatory, and antiapoptotic biomarkers

Quality analysis and effect of reused water on some biological characteristics of Phaseolus vulgaris and Pisum sativum

Seeds of Phaseolus vulgaris L. and Pisum sativum were planted in separated pots, then these pots divided into two groups, each group divided into four subgroups. Four different wastewater were used to irrigate the treatments. The results showed the effects induced by irrigated wastewater on P. vulgaris L. and P. sativum. The degree of water salinity induced increasing SOD, protein content and the area of xylem elements, but reduced chlorophyll-α in P. vulgaris. The CAT, protein and chlorophyll-α were increased in in P. sativum as a result to salinity which also reduces the area of xylem elements

Metal-free visible-light-induced dithiol–ene clicking via carbon nitride to valorize 4-pentenoic acid as a functional monomer

The necessity for more bio-based building blocks and processes have led to utilizing new polymerization approaches with a lower carbon footprint. Here, we demonstrate the synthesis of a visible-light-induced dithiol–ene clicking reaction between lignocellulosic biomass-derivable 4-pentenoic acid (4-PEA) and different dithiols, i.e., 1,2-ethanedithiol (EDT), 2,2-(ethylenedioxy)diethanethiol (EDDT), and 1,4-benzenedimethanethiol (BDT), using graphitic carbon nitride (g-CN) as a metal-free photocatalyst. The formation of dicarboxylic acid functional monomers were confirmed using 1H NMR and FT-IR. Furthermore, polyamides were synthesized from the dicarboxylic acid functional monomers to demonstrate the applicability of the monomers yielding new polyamide end polymers

Resin-supported iridium complex for low-temperature vanillin hydrogenation using formic acid in water

Biorefinery seeks to utilize biomass waste streams as a source of chemical precursors with which to feed the chemical industry. This goal seeks to replace petroleum as the main feedstock,} however this task requires the development of efficient catalysts capable of transforming substances derived from biomass into useful chemical products. In this study{,} we demonstrate that a highly-active iridium complex can be solid-supported and used as a low-temperature catalyst for both the decomposition of formic acid (FA) to produce hydrogen{,} and as a hydrogenation catalyst to produce vanillyl alcohol (VA) and 2-methoxy-4-methylphenol (MMP) from vanillin (V); a lignin-derived feedstock. These hydrogenation products are promising precursors for epoxy resins and thus demonstrate an approach for their production without the need for petroleum. In contrast to other catalysts that require temperatures exceeding 100 °C{,} here we accomplish this at a temperature of <50 °C in water under autogenous pressure. This approach provides an avenue towards biorefinery with lower energy demands{, which is central to the decentralization and broad implementation. We found that the high activity of the iridium complex transfers to the solid-support and is capable of accelerating the rate determining step; the decomposition of FA into hydrogen and carbon dioxide. The yield of both VA and MMP can be independently tuned depending on the temperature. The simplicity of this approach expands the utility of molecular metal complexes and provides new catalyst opportunities in biorefinery