Degradation of estriol (E3) and transformation pathways after applying photochemical removal processes in natural surface water.

Steroidal hormones such as estriol (E3), are resistant to biodegradation; hence their removal by conventional treatment systems (aerobic and anaerobic) facilities is limited. These substances are detected in surface water, and present risks to the aquatic ecosystem and humans via potential biological activity. Photochemical treatments can be used to remove E3; however, just a few studies have analyzed the kinetics, intermediates, and E3 degradation pathways in natural surface water. In this study, the behavior of E3 under ultraviolet irradiation associated with H2O2, O3 or TiO2 was investigated to determine the degradation potential and the transformation pathways in reactions performed with a natural surface water sample. E3 degradation kinetics (200 ppb) fitted well to the pseudo-first-order kinetics model, with kinetic constant k in the following order: kUV/O3 > kUV/TiO2 > kUV/H2O2 > kUV. The mechanism of degradation using different advanced oxidative processes seemed to be similar and 12 transformation byproducts were identified, with 11 of them being reported here for the first time. The byproducts could be formed by the opening of the aromatic ring and addition of a hydroxyl radical. A possible route of E3 degradation was proposed based on the byproducts identified, and some of the byproducts presented chronic toxicity to aquatic organisms, demonstrating the risks of exposure.

Ultrasound-assisted hydrolysis of waste cooking oil catalyzed by homemade lipases.

This study aimed to evaluate the waste cooking oil (WCO) hydrolysis in ultrasonic system using lipase as catalyst. Lipase was produced by the fungus Aspergillus niger via solid state fermentation (SSF) using canola meal as substrate. Prior to the hydrolysis reaction, the lipase behavior when subjected to ultrasound was evaluated by varying the temperature of the ultrasonic bath, the exposure time and the equipment power. Having optimized the treatment on ultrasound, the WCO hydrolysis reaction was carried out by evaluating the oil:water ratio and the lipase concentration. For a greater homogenization of the reaction medium, a mechanical stirrer at 170rpm was used. All steps were analyzed by experimental design technique. The lipase treatment in ultrasound generated an increase of about 320% in its hydrolytic activity using 50% of ultrasonic power for 25min. at 45°C. The results of the experimental design conducted for ultrasound-assisted hydrolysis showed that the best condition was using an oil:water ratio of 1:3 (v:v) and enzyme concentration of 15% (v/v), generating 62.67µmol/mL of free fatty acids (FFA) in 12h of reaction. Thus, the use of Aspergillus niger lipase as a catalyst for hydrolysis reaction of WCO can be considered as a possible pretreatment technique of the oil in order to accelerate its degradation.

Continuous lipase-catalyzed esterification of soybean fatty acids under ultrasound irradiation.

This work investigates the continuous production of alkyl esters from soybean fatty acid (FA) charges using immobilized Novozym 435 as catalyst. The experiments were performed in a packed-bed bioreactor evaluating the effects of FA charge to alcohol (methanol and ethanol) molar ratio, from 1:1 to 1:6, substrate flow rate in the range of 0.5-2.5 mL/min and output irradiation power up to 154 W, at fixed temperature of 65 °C, on the reaction conversion. Results showed that almost complete conversions to fatty acids ethyl esters were achieved at mild ultrasonic power (61.6 W), FA to ethanol molar ratio of 1:6, operating temperature (65 °C) and remained nearly constant for long-term reactions without negligible enzyme activity losses.

Continuous lipase-catalyzed production of fatty acid ethyl esters from soybean oil in compressed fluids.

This work investigates the continuous production of fatty acid ethyl esters from soybean oil in compressed fluids, namely carbon dioxide, propane and n-butane, using immobilized Novozym 435 as catalyst. The experiments were performed in a packed-bed bioreactor evaluating the effects of temperature in the range of 30-70 degrees C, from 50 to 150 bar, oil to ethanol molar ratio of 1:6-1:18 and solvent to substrates mass ratio of 4:1-10:1. In contrast to the use of carbon dioxide and n-butane, results showed that lipase-catalyzed alcoholysis in a continuous tubular reactor in compressed propane might be a potential route to biodiesel production as high reaction conversions were achieved at mild temperature (70 degrees C) and pressure (60 bar) conditions in short reaction times.

Production and partial characterization of lipases from a newly isolated Penicillium sp. using experimental design.

AIMS: The objective of this work was to investigate the lipase production by a newly isolated Penicillium sp., using experimental design technique, in submerged fermentation using a medium based on peptone, yeast extract, NaCl and olive oil, as well as to characterize the crude enzymatic extracts obtained. METHODS AND RESULTS: Lipase activity values of 9.5 U ml(-1) in 96 h of fermentation was obtained at the maximized operational conditions of peptone, yeast extract, NaCl and olive oil concentrations (g l(-1)) of 20.0, 5.0, 5.0 and of 10.0 respectively. The partial characterization of crude enzymatic extract obtained by submerged fermentation showed optimum activity at pH range from 4.9 to 5.5 and temperature from 37 degrees C to 42 degrees C. The crude extract maintained its initial activity at freezing temperatures up to 100 days. CONCLUSIONS: A newly isolated strain of Penicillium sp. used in this work yielded good lipase activities compared to the literature. SIGNIFICANCE AND IMPACT OF THE STUDY: The growing interest in lipase production is related to the potential biotechnological applications that these enzymes present. New lipase producers are relevant to finding enzymes with different catalytic properties of commercial interest could be obtained, without using genetically modified organisms (GMO).

Comparison of insulin detemir and insulin glargine in subjects with Type 1 diabetes using intensive insulin therapy.

AIMS: To compare glycaemic control and risk of hypoglycaemia of twice-daily insulin detemir with once-daily insulin glargine in subjects with Type 1 diabetes. METHODS: In this 26-week, multicentre, open-label, parallel-group trial, 320 subjects with Type 1 diabetes received either insulin detemir twice daily or insulin glargine once daily. each in combination with premeal insulin aspart. RESULTS: After 26 weeks, HbA(1c) had decreased from 8.8 to 8.2% in the insulin detemir group and from 8.7 to 8.2% in the insulin glargine group. Home-measured fasting plasma glucose (PG) was lower with insulin glargine than with insulin detemir (7.0 vs. 7.7 mmol/l, P < 0.001). The overall shape of the home-measured nine-point PG profiles was comparable between treatments (P = 0.125). Overall, there was no significant difference in within-subject variation in PG (P = 0.437). Within-subject variation in predinner PG was lower with insulin detemir than with insulin glargine (P < 0.05). The overall risk of hypoglycaemia was similar with no differences in confirmed hypoglycaemia. However, the risk of severe and nocturnal hypoglycaemia was 72% and 32%, respectively, lower with insulin detemir than with insulin glargine (P < 0.05). Body weight gain was not significantly different comparing insulin detemir and insulin glargine (0.52 kg vs. 0.96 kg, P = 0.193). CONCLUSIONS: Treatment with twice-daily insulin detemir or once-daily insulin glargine, each in combination with insulin aspart, resulted in similar glycaemic control. The overall risk of hypoglycaemia was comparable, whereas the risks of both severe and nocturnal hypoglycaemia were significantly lower with insulin detemir.

Safety and efficacy of 7-day rabeprazole- and omeprazole-based triple therapy regimens for the eradication of Helicobacter pylori in patients with documented peptic ulcer disease.

AIM: A double-blind, randomized study was designed to determine whether rabeprazole- and omeprazole-based triple therapy regimens are therapeutically equivalent in the eradication of Helicobacter pylori. METHODS: Three hundred and forty-five patients with current or previously active peptic ulcer and a positive H. pylori urease test were randomly assigned to receive RCA, OCA, RCM or OCM twice daily for 7 days (R, rabeprazole 20 mg; O, omeprazole 20 mg; C, clarithromycin 500 mg; A, amoxicillin 1000 mg; M, metronidazole 400 mg). H. pylori eradication was documented by negative 13C-urea breath tests at 4 and 12 weeks, and was evaluated using a 2 x 2 factorial design with proton pump inhibitor and antibiotic as factors. RESULTS: Overall eradication rates (per protocol/intention-to-treat) were 87%/77% and 85%/75% with rabeprazole and omeprazole, respectively (not significant). However, a statistical interaction between proton pump inhibitor and antibiotic was identified. RCA produced a somewhat higher eradication rate than OCA (94% vs. 84%; difference, 9.8%; 95% confidence interval, - 0.7% to + 20.4%), whereas RCM produced a lower eradication rate than OCM (79% vs. 86%; difference, 8.1%; 95% confidence interval, - 21.4% to + 5.1%). Ulcer healing rates were > 90% with H. pylori eradication. Each regimen was well tolerated. CONCLUSIONS: Rabeprazole- and omeprazole-based triple therapy regimens are therapeutically equivalent in the eradication of H. pylori and well tolerated. The statistical interaction observed between the proton pump inhibitor and supplementary antibiotic may be due to chance.

One-week triple therapy with esomeprazole provides effective eradication of Helicobacter pylori in duodenal ulcer disease.

BACKGROUND: Esomeprazole is the first proton pump inhibitor to be developed as an optical isomer for the treatment of acid-related diseases. METHODS: Four hundred and forty eight duodenal ulcer patients with Helicobacter pylori infection, confirmed by 13C-urea breath test (UBT), and no current ulcer, were randomised to double-blind treatment with esomeprazole 20 mg twice daily (b.d.) (n=224) or omeprazole 20 mg b.d. (n=224), in combination with amoxicillin 1 g b.d. and clarithromycin 500 mg b.d. for 1 week (EAC and OAC, respectively). A negative UBT at both 4 and 8 weeks after completing therapy indicated successful H. pylori eradication. RESULTS: Intention-to-treat (ITT) analysis comprised 400 patients (EAC, n=204; OAC, n=196) and per protocol (PP) analysis 377 patients (EAC, n=192; OAC, n=185). Eradication rates (95% confidence intervals) for ITT and PP populations were: EAC, 90% (85-94%) and 91% (86-94%); OAC, 88% (82-92%) and 91% (86-95%). Between-group differences in eradication rates were not statistically significant. Both regimens were well tolerated, with an adverse event profile and frequency typical of proton pump inhibitor plus antibiotic combination therapy. CONCLUSIONS: Esomeprazole-based triple therapy for 1 week is highly effective in eradicating H. pylori infection in duodenal ulcer disease, offers comparable efficacy to omeprazole-based therapy, and is well tolerated.

The GU-MACH study: the effect of 1-week omeprazole triple therapy on Helicobacter pylori infection in patients with gastric ulcer.

AIMS: To study the efficacy of omeprazole triple therapy in the eradication of Helicobacter pylori in patients with active gastric ulcer, and to assess healing and relapse of gastric ulcer. METHODS: A double-blind, randomized study was carried out in 18 centres in Germany, Hungary and Poland. Patients (n = 160) with gastric ulcer and a positive H. pylori screening test were randomized to a 7-day twice daily treatment with omeprazole 20 mg, clarithromycin 500 mg and amoxycillin 1000 mg (OAC) or omeprazole 20 mg, clarithromycin 250 mg and metronidazole 400 mg (OMC), or with omeprazole 20 mg once daily (O). After completion of this 1-week treatment, patients were treated with omeprazole until healing (maximum 12 weeks), and followed for 6 months. H. pylori was assessed by urea breath test (UBT) and histology. RESULTS: Eradication rates ITT were OAC 79% (95% CI: 65-90%), OMC 86% (95% CI: 73-94%) and O 4% (95% CI: 0-14%). Eradication rates PP were OAC 83% (95% CI: 68-93%), OMC 93% (95% CI: 80-98%) and O 3% (95% CI: 0-13%). Gastric ulcer relapses occurred in 5, 0 and 11 patients in the groups, respectively. CONCLUSIONS: The results from the study demonstrate that OMC and OAC 1-week regimens are safe and effective for eradication of H. pylori in gastric ulcer patients, and that ulcer relapse is infrequent after successful eradication.