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This study reports results of an entire green methodology combining bioreduction by baker’s yeast supported cells and a medium formed by glycerol and scCO2 to a β-ketoester biotransformation. Fermented cells of Saccharomyces cerevisiae, immobilized in calcium alginate beads, were chosen to catalyze ethyl acetoacetate reduction in a biphasic system of scCO2 and glycerol 20% (vol/vol) (T = 45 °C and P = 100 bar). The bioreduction was also carried out at normal conditions (T = 45°C and P = 0.92 bar) in n-heptane and glycerol 20% (vol/vol). Using scCO2/glycerol the reaction reached 77% of conversion in 6 h, and the enantiopure (S)-ethyl-3-hydroxybutyrate (enantiomeric excess > 99%) was observed as the unique product. The same reaction under normal conditions led to only 12% conversion in 6 h. The approach evaluated in this study showed a great potential to be employed as a greener alternative to conventional bioreduction process.

A new series of 3,6-disubstituted 2-(methylthio)-4-(trifluoromethyl)-3,4-dihydropyrimidin-4-ols displaying methyl, phenyl, aryl, and heteroaryl groups at the 6-position; and methyl, ethyl, allyl, and phenyl groups at the 3-position of the dihydropyrimidine ring, were synthesized and evaluated in vitro for acetylcholinesterase (AChE) inhibitory activity. Seven compounds showed activity with IC50 values in the lower micromolar range. The compound 4-trifluoromethyl-6-(4-fluorophenyl)-3-methyl-2-methylthio-3,4-dihydropyrimidin-4-ol (6e) had the best inhibitory activity (IC50 2.2±0.9 μM) and this inhibition was characterized as competitive. The molecular docking study showed that the AChE enzyme accommodates compound 6e in its catalytic site. The enantiomers of compound 6e, present similar interactions: π–π stacking interactions between the aromatic ring of the ligand's 4-fluorophenyl moiety and the aromatic rings of the electron-rich Trp84; and H-bonds between the hydroxyl group of Tyr121 and the hydroxyl moiety from 6e. The antioxidant effect of the dihydropyrimidin-4-ols was also investigated. This article is protected by copyright. All rights reserved.

A low-cost enzymatic catalyst for biodiesel production can be produced by growing a lipase-producing organism in solid-state fermentation and then drying the solids after the fermentation. Recently, we cultivated Burkholderia cepacia on a mixture of sugar cane bagasse and sunflower seed meal and used the dried fermented solid to catalyze the esterification of fatty acids with ethanol in a solvent-free system (Soares et al., Fuel (2015) 159, 364–372). During the reaction, up to 30% of the reaction medium sorbed onto the dried fermented solid, with the sorbed medium having a composition different from that of the bulk phase. In the current work, we develop a combined sorption-kinetic model to describe the reaction kinetics in this system. The sorption of the medium components onto the fermented solid follows a multicomponent Langmuir isotherm, while the kinetic equation is expressed in terms of the composition of the sorbed phase. With a single set of parameters, the model adjusted well to the experimental results obtained by Soares et al. for three different ethanol to fatty acid molar ratios (1:1, 1.5:1 and 3:1), not only for the overall conversion profile, but also for the compositions of the bulk phase and the sorbed phase. The model has potential to be used to guide the scale-up of our system.

A fermented solid containing lipases was produced by growing Burkholderia cepacia LTEB11 on a 1:1 mixture, by mass, of sugarcane bagasse and sunflower seed meal. This fermented solid was dried and then used in a packed-bed bioreactor to catalyze the esterification of fatty acids from soybean soapstock acid oil with ethanol in a solvent-free system. The bioreactor was operated in batch mode, with the medium being recirculated from the reservoir through the bed in a closed-loop system. During the reaction, the bulk reaction medium separated into organic and aqueous phases. Additionally, up to 30% of the reaction medium was held as a sorbed phase on the fermented solids. The composition of this sorbed phase, which represents the microenvironment of the lipases, was significantly different from the compositions of the bulk organic and aqueous phases. It was predominantly polar, with water or ethanol as the major component, but also contained significant amounts of ester. Importantly, the molar ratios of ethanol to fatty acid in the sorbed phase were significantly higher than those in the bulk reaction medium; this has implications for the reaction, since ethanol is known to cause inhibition and denaturation of lipases.

We obtained liquid–liquid equilibrium (LLE) data for the systems involved in biodiesel production from a low-value feedstock, namely fatty acids from soybean soapstock acid oil (FA-SSAO), at 303.2 and 323.2 K. The systems studied were water + ethanol + FA-SSAO and water + ethanol + fatty acid ethyl esters (EE-SSAO). The mass fractions of the compounds in equilibrium in the two phases were determined analytically, whereas the binodal curves were obtained by the cloud-point method. The increase in temperature from 303.2 and 323.2 K slightly increased the miscibility of the EE-SSAO system. We found that ethanol is more soluble in water than in either FA-SSAO or EE-SSAO, and that an increase in ethanol content in either the FA-SSAO-rich phase or the EE-SSAO-rich phase enhances water solubility in these phases. The experimental data were satisfactorily modeled by the NRTL and UNIQUAC approaches.

This study investigated the effect of quercetin on nucleoside triphosphate diphosphohydrolase (NTP-Dase), 50-nucleotidase, adenosine deaminase (ADA), and acetylcholinesterase (AChE) activities in synaptosomes from cerebral cortex of adult rats exposed to cadmium (Cd). Rats were exposed to Cd (2.5 mg/Kg) and quercetin (5, 25 or 50 mg/Kg) by gavage for 45 days. Rats were randomly divided into eight groups (n = 8-10): saline/ethanol, saline/Querc 5 mg/kg, saline/Querc 25 mg/kg, saline/Querc 50 mg/kg, Cd/ethanol, Cd/Querc 5 mg/kg, Cd/Querc 25 mg/kg, and Cd/Querc 50 mg/kg. Results demonstrated that AChE activity increased in the Cd/ethanol group when compared to saline/ethanol group. Treatment with quercetin prevented the increase in AChE activity when compared to Cd/ethanol group. Quercetin treatment prevented the cadmium-induced increase in NTPDase, 5-nucleotidase, and ADA activities in Cd/ethanol group when compared to saline/ethanol group. Our data showed that quercetin have a protector effect against Cd intoxication. This way, is a promising candidate among the flavonoids to be investigated as a therapeutic agent to attenuate neurological disorders associated with Cd intoxication.

The aim of this study is to evaluate the role of cholinesterases as an inflammatory marker in acute and chronic infection by Trypanosoma evansi in rabbits experimentally infected. Twelve adult female New Zealand rabbits were used and divided into two groups with 6 animals each: control group (rabbits 1-6) and infected group (rabbits 7-12). Infected group received intraperitoneally 0.5 mL of blood from a rat containing 108 parasites per animal. Blood samples used for cholinesterases evaluation were collected on days 0, 2, 7, 12, 27, 42, 57, 87, 102 and 118 days post-inoculation (PI). Increased activity (P0.05) was observed in the encephalic structures. The increased activities of AChE and BChE probably have a pro-inflammatory purpose, attempting to reduce the concentration of acetylcholine, a neurotransmitter which has an anti-inflammatory property. Therefore, cholinesterase may be inflammatory markers in infection with T. evansi in rabbits.O objetivo do presente estudo é avaliar o papel das colinesterases como marcadores inflamatórios nas fases aguda e crônica da infecção por T. evansi em coelhos infectados experimentalmente. Foram utilizados 12 coelhos adultos, fêmeas, da raça Nova Zelândia, divididos em dois grupos: um grupo controle, com seis animais (coelhos 1-6), e um grupo infectado, com seis animais (coelhos 7-12). Os animais pertencentes ao grupo infectados receberam, pela via intraperitoneal, 0,5 mL de sangue de rato contendo 108 tripanossomas por animal. Amostras do sangue utilizado para avaliação das colinesterases foram coletadas nos dias 0, 2, 7, 12, 27, 42, 57, 87, 102 e 118 pós-inoculação (PI). Aumento (P0,05) foi observada nas estruturas encefálicas. O aumento de atividade da AChE e BChE provavelmente tenha finalidade pró-inflamatória, a fim de reduzir as concentrações de acetilcolina, neurotransmissor que apresenta propriedade anti-inflamatória. Portanto, as colinesterases podem ser marcadores inflamatórios na infecção por T. evansi em coelhos.

The present study investigated the effects of a 6-week swimming training on blood pressure, nitric oxide (NO) levels and oxidative stress parameters such as protein and lipid oxidation, antioxidant enzyme activity and endogenous non-enzymatic antioxidant content in kidney and circulating fluids, as well as on serum biochemical parameters (cholesterol, triglycerides, urea and creatinine) from Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME)-induced hypertension treated rats. Animals were divided into four groups (n = 10): Control, Exercise, L-NAME and Exercise L-NAME. Results showed that exercise prevented a decrease in NO levels in hypertensive rats (P

The present study investigated the effects of resveratrol (RV), a polyphenol with potent antioxidant properties, on oxidative stress parameters in liver and kidney, as well as on serum biochemical parameters of streptozotocin (STZ)-induced diabetic rats. Animals were divided into six groups (n = 8): control/saline; control/RV 10 mg/kg; control/RV 20 mg/kg; diabetic/saline; diabetic/RV10 mg/kg; diabetic/RV 20 mg/kg. After 30 days of treatment with resveratrol the animals were sacrificed and the liver, kidney and serum were used for experimental determinations. Results showed that TBARS levels were significantly increased in the diabetic/saline group and the administration of resveratrol prevented this increase in the diabetic/RV10 and diabetic/RV20 groups (P

Background Cholinergic enzyme activities are altered in hypertension, reflecting a low-grade inflammation. Regular physical exercise exerts anti-inflammatory effects and has been described as a coadjutant in the treatment of hypertension. In this study, we investigated the effect of 6 weeks of swimming training on cholinergic enzyme activities (acetylcholinesterase and butyrylcholinesterase) in Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME)–induced hypertensive rats. Methods The rats were divided into 4 groups: control (n = 10), exercise (n = 10), L-NAME (n = 10), and exercise L-NAME (n = 10). The animals were trained 5 times per week in an adapted swimming system for 60 minutes with a gradual increase of the workload up to 5% of animal’s body weight. Enzyme activities were measured spectrophotometrically in lymphocytes, whole blood, and serum. r esults A significant rise in acetylcholinesterase activity was observed in lymphocytes and whole blood as well as in serum butyrylcholinesterase activity in the L-NAME group when compared with the other groups (P < 0.05), and the increase in cholinesterase activities was positively correlated with the rise in blood pressure (r = 0.5721, r = 0.6121, and r = 0.5811, respectively). Swimming training was efficient in preventing these alterations in the exercise L-NAME group, which displayed values similar to those of the control group. Exercise training demonstrated a significant hypotensive effect in hypertensive rats. conclusions Exercise training was shown to prevent increased cholinesterase related to inflammatory processes in hypertensive rats, providing a new insight about protective exercise mechanisms to avoid hypertension-related inflammation.

The present study investigated the effects of a 6-week swimming training on blood pressure, nitric oxide (NO) levels and oxidative stress parameters such as protein and lipid oxidation, antioxidant enzyme activity and endogenous non-enzymatic antioxidant content in kidney and circulating fluids, as well as on serum biochemical parameters (cholesterol, triglycerides, urea and creatinine) from Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME)-induced hypertension treated rats. Animals were divided into four groups (n = 10): Control, Exercise, L-NAME and Exercise L-NAME. Results showed that exercise prevented a decrease in NO levels in hypertensive rats (P0·05). An increase in protein and lipid oxidation observed in the L-NAME-treated group was reverted by physical training in serum from the Exercise L-NAME group (P0·05). A decrease in the catalase (CAT) and superoxide dismutase (SOD) activities in the L-NAME group was observed when compared with normotensive groups (P0·05). In kidney, exercise significantly augmented the CAT and SOD activities in the Exercise L-NAME group when compared with the L-NAME group (P0·05). There was a decrease in the non-protein thiols (NPSH) levels in the L-NAME-treated group when compared with the normotensive groups (P0·05). In the Exercise L-NAME group, there was an increase in NPSH levels when compared with the L-NAME group (P0·05). The elevation in serum cholesterol, triglycerides, urea and creatinine levels observed in the L-NAME group were reverted to levels close to normal by exercise in the Exercise L-NAME group (P0·05). Exercise training had hypotensive effect, reducing blood pressure in the Exercise L-NAME group (P0·05). These findings suggest that physical training could have a protector effect against oxidative damage and renal injury caused by hypertension.