Pycnoporus cinnabarinus glyoxal oxidases display differential catalytic efficiencies on 5‑hydroxymethylfurfural and its oxidized derivatives

Background: 5-Hydroxymethylfurfural (HMF), a major residual component of a lignocellulosic bio-refinery process, can be transformed into fundamental building blocks for green chemistry via oxidation. While chemical methods are well established, interest is also being directed into the enzymatic oxidation of HMF into the bio-plastic precursor 2,5-furandicarboxylic acid (FDCA). Results: We demonstrate that three glyoxal oxidases (PciGLOX) isoenzymes from the Basidiomycete fungus Pycnoporus cinnabarinus were able to oxidize HMF, with PciGLOX2 and PciGLOX3 being the most efficient. The major reaction product obtained with the three isoenzymes was 5-hydroxymethyl-2-furancarboxylic (HMFCA), a precursor in polyesters and pharmaceuticals production, and very little subsequent conversion of this compound was observed. However, small concentrations of FDCA, a substitute for terephthalic acid in the production of polyesters, were also obtained. The oxidation of HMF was significantly boosted in the presence of catalase for PciGLOX2, leading to 70% HMFCA yield. The highest conversion percentages were observed on 2,5-furandicarboxaldehyde (DFF), a minor product from the reaction of PciGLOX on HMF. To bypass HMFCA accumulation and exploit the efficiency of PciGLOX in oxidizing DFF and 5-formyl-2-furan carboxylic acid (FFCA) towards FDCA production, HMF was oxidized in a cascade reaction with an aryl alcohol oxidase (UmaAAO). After 2 h of reaction, UmaAAO completely oxidized HMF to DFF and further to FFCA, with FDCA only being detected when PciGLOX3 was added to the reaction. The maximum yield of 16% FDCA was obtained 24 h after the addition of PciGLOX3 in the presence of catalase. Conclusions: At least two conversion pathways for HMF oxidation can be considered for PciGLOX; however, the highest selectivity was seen towards the production of the valuable polyester precursor HMFCA. The three isoenzymes showed differences in their catalytic efficiencies and substrate specificities when reacted with HMF derivatives

Diplotaxis simplex suppresses postprandial hyperglycemia in mice by inhibiting key-enzymes linked to type 2 diabetes

Abstract Nutritional properties of Diplotaxis simplex Spreng., Brassicaceae, an edible wild cruciferous largely distributed in North Africa, were investigated. Potassium (3690–3780 mg/100 g) and calcium (900–1170 mg/100 g) were the most concentrated minerals. Linoleinic acid was found to be the main fatty acid (25.4–27.7%), followed by palmitic acid (13.2–15.3%). Moreover, lipidic fraction of leaves was characterized by a relatively high rate of ethyl linoleate (14.4%) and phytol (17.6%). Ethyl acetate extract of D. simplex flowers showed concentration-dependent α-amylase (IC50 3.46 mg/ml) and α-glucosidase (IC50 0.046 mg/ml) inhibitory activities. The positive in vitro enzymes inhibition was confirmed by a maltose tolerance test, which showed that treatment with flowers extract significantly inhibited the rise in blood glucose levels of maltose-loaded mice comparable to the standard antihyperglycemic agent acarbose. From these results, it may be concluded that D. simplex flowers can be used effectively as a safer alternative therapy to control postprandial hyperglycemia

Pycnoporus cinnabarinus glyoxal oxidases display differential catalytic efficiencies on 5‑hydroxymethylfurfural and its oxidized derivatives

International audienceBackground: 5-Hydroxymethylfurfural (HMF), a major residual component of a lignocellulosic bio-refinery process, can be transformed into fundamental building blocks for green chemistry via oxidation. While chemical methods are well established, interest is also being directed into the enzymatic oxidation of HMF into the bio-plastic precursor 2,5-furandicarboxylic acid (FDCA). Results: We demonstrate that three glyoxal oxidases (PciGLOX) isoenzymes from the Basidiomycete fungus Pycnoporus cinnabarinus were able to oxidize HMF, with PciGLOX2 and PciGLOX3 being the most efficient. The major reaction product obtained with the three isoenzymes was 5-hydroxymethyl-2-furancarboxylic (HMFCA), a precursor in polyesters and pharmaceuticals production, and very little subsequent conversion of this compound was observed. However, small concentrations of FDCA, a substitute for terephthalic acid in the production of polyesters, were also obtained. The oxidation of HMF was significantly boosted in the presence of catalase for PciGLOX2, leading to 70% HMFCA yield. The highest conversion percentages were observed on 2,5-furandicarboxaldehyde (DFF), a minor product from the reaction of PciGLOX on HMF. To bypass HMFCA accumulation and exploit the efficiency of PciGLOX in oxidizing DFF and 5-formyl-2-furan carboxylic acid (FFCA) towards FDCA production, HMF was oxidized in a cascade reaction with an aryl alcohol oxidase (UmaAAO). After 2 h of reaction, UmaAAO completely oxidized HMF to DFF and further to FFCA, with FDCA only being detected when PciGLOX3 was added to the reaction. The maximum yield of 16% FDCA was obtained 24 h after the addition of PciGLOX3 in the presence of catalase. Conclusions: At least two conversion pathways for HMF oxidation can be considered for PciGLOX; however, the highest selectivity was seen towards the production of the valuable polyester precursor HMFCA. The three isoenzymes showed differences in their catalytic efficiencies and substrate specificities when reacted with HMF derivatives

Soluble ACE2 and angiotensin II levels are modulated in hypertensive COVID-19 patients treated with different antihypertension drugs.

This study examines the effect of antihypertensive drugs on ACE2 and Angiotensin II levels in hypertensive COVID-19 patients. Hypertension is a common comorbidity among severe COVID-19 patients. ACE2 expression can be modulated by antihypertensive drugs such as ACEis and ARBs, which may affect COVID-19's prognosis. BB and CCB reduce mortality, according to some evidence. Their effect on circulating levels of ACE2 and angiotensin II, as well as the severity of COVID-19, is less well studied. The clinical data were collected from 200 patients in four different antihypertensive medication classes (ACEi, ARB, BB, and CCB). Angiotensin II and ACE2 levels were determined using standard ELISA kits. ACE2, angiotensin II, and other clinical indices were evaluated by linear regression models. Patients on ACEi ( = 57), ARB ( = 68), BB ( = 15), or CCB ( = 30) in this study had mild ( = 76), moderate ( = 76), or severe ( = 52) COVID-19. ACE2 levels were higher in COVID-19 patients with severe disease ( = 0.04) than mild ( = 0.07) and moderate ( = 0.007). The length of hospital stay is correlated with ACE2 levels ( = 0.3,  = 0.003). Angiotensin II levels decreased with severity ( = 0.04). Higher ACE2 levels are associated with higher CRP and D-dimer levels. Elevated Angiotensin II was associated with low levels of CRP, D-dimer, and troponin. ACE2 levels increase with disease severity in patients taking an ARB ( = 0.01), patients taking ACEi, the degree of disease severity was associated with a decrease in angiotensin II. BB patients had the lowest disease severity. We found different levels of soluble ACE2, and angiotensin II are observed among COVID-19 patients taking different antihypertensive medications and exhibiting varying levels of disease severity. COVID-19 severity increases with elevated ACE2 levels and lower angiotensin II levels indicating that BB treatment reduces severity regardless of levels of ACE2 and angiotensin II.Open Access funding is provided by the Qatar National Library. This report was made possible by an RRC award [RRC-2-076] from the Qatar National Research Fund (a member of The Qatar Foundation). The statements made herein are solely the responsibility of the authors. We would like to acknowledge Qatar BioBank for helping with the logistics of the collected samples, Prof. Nahla Afifi, Dr. Marwa A. El Deeb, and Ms. Sidra Abdulshakoor. The publication of this paper is covered by Qatar National Library

Impact of the first wave of COVID-19 epidemy on the surgical management of sigmoid diverticular disease in France: National French retrospective study

International audienceObjective: To analyze the surgical management of sigmoid diverticular disease (SDD) before, during, and after the first containment rules (CR) for the first wave of COVID-19.Methods: From the French Surgical Association multicenter series, this study included all patients operated on between January 2018 and September 2021. Three groups were compared: A (before CR period: 01/01/18-03/16/20), B (CR period: 03/17/20-05/03/20), and C (post CR period: 05/04/20-09/30/21).Results: A total of 1965 patients (A n = 1517, B n = 52, C n = 396) were included. The A group had significantly more previous SDD compared to the two other groups (p = 0.007), especially complicated (p = 0.0004). The rate of peritonitis was significantly higher in the B (46.1%) and C (38.4%) groups compared to the A group (31.7%) (p = 0.034 and p = 0.014). As regards surgical treatment, Hartmann's procedure was more often performed in the B group (44.2%, vs A 25.5% and C 26.8%, p = 0.01). Mortality at 90 days was significantly higher in the B group (9.6%, vs A 4% and C 6.3%, p = 0.034). This difference was also significant between the A and B groups (p = 0.048), as well as between the A and C groups (p = 0.05). There was no significant difference between the three groups in terms of postoperative morbidity.Conclusion: This study shows that the management of SDD was impacted by COVID-19 at CR, but also after and until September 2021, both on the initial clinical presentation and on postoperative mortality