Electrostatic and Water Content Effects on Yarrowia lipolytica Lipase Immobilization by Adsorption.

Aims: In the present investigation, an attempt has been made to explain lipase immobilization by adsorption on three minerals matrixes, i.e. Celite 545, Silica gel (60G) and Avicel (PH 101). Study Design: immobilization by absorption on minerals matrixes, water content by volumetric karl Fischer titration and surface potentials using a particle charge detector Mutek PCD 03 were used. Place and Duration of Study: Walloon Centre of Industrial Biology (CWBI) Unit of Bio- Industries, University of Liege, Gembloux Agro-Bio Tech, Passage des Deportes 2, B- 5030 Gembloux, Belgium between Jun 2012 and jun 2013. Methodology: A methodical order was developed whereby the influences of water content, surface potentials and pH, on immobilization by adsorption were explored. Adsorbed YLL was used to understand an interesterification reaction between rapeseed oil and milk fat in comparison with a commercial silica-granulated Thermomyces lanuginosus lipase (Lipozyme TL IM). Results: Maximum immobilization yield was obtained with Celite (70%) and the lowest with silica gel (29%). Total water content of free and immobilized lipase was determined by volumetric Karl Fischer titration. The water content of Silica gel was higher than the one of other supports. Water content of silica gel could prevent the enzyme fixation. These results could be explained by the adsorption being governed mainly by electrostatic interactions between the enzyme and matrix. This hypothesis was further reinforced by measurements of electrical potential. They showed a lowest negative potential of Silica gel after enzyme adsorption in comparison to Celite. Conclusion: From these results celite was designated as an efficient matrix to immobilize Yarrowia lipolytica lipase (YLL) by adsorption. This performed system was used to realize an interesterification reaction between rapeseed oil and milk fat in comparison with a commercial silica-granulated Thermomyces lanuginosus lipase (Lipozyme TL IM).

Ethanol Production from Glycerol by the Yeast Pachysolen tannophilus Immobilized on Celite during Repeated-Batch Flask Culture

We investigated a novel process for production of ethanol from glycerol using the yeast Pachysolen tannophilus. After optimization of the fermentation medium, repeated-batch flask culture was performed over a period of 378 hr using yeast cells immobilized on Celite. Our results indicated that the use of Celite for immobilization of P. tannophilus was a practical approach for ethanol production from glycerol, and should be suitable for industrial ethanol production.

Influence of Aprotinin on Kaolin and Celite on Activated Clotting Time in Cardiac Surgery / 대한마취과학회지

BACKGROUND: High-dose aprotinin appears to enhance the anticoagulant effects of heparin, as documented by increases in the activated clotting times (ACTs) during cardiopulmonary bypass. This increase of the ACT in the presence of aprotinin and heparin is due to the use of celite as surface activator. We compared celite and kaolin as surface activators for the measurement of the ACT in cardiac surgical patients treated with high dose aprotinin. METHODS: This study included 25 patients who were scheduled for coronary bypass graft surgery and reoperation of cardiac valvular surgery. The 2 million units of aprotinin were added to the pump prime of heart-lung machine. The dosage of heparin and protamine was 3 mg/kg respectively. Whole blood was sampled 10 minutes after induction, heparin administration, cardiopulmonary bypass(CPB), 10 minutes before the termination of CPB and 10 minutes after protamine administration. The ACT was measured with Hemochron 801 blood coagulation timer with 12 mg of either celite (C-ACT) or kaolin (K-ACT) used as surface activator. RESULTS: At 10 minutes after induction and heparin administration, celite and kaolin ACTs were l20+/-28, 541+/-247 seconds and 126+/-23, 559+/-267 seconds rcspectively. But 10 minutes after initiation of CPB and before the termination of CPB, celite ACTs were 941+/-238 and 787+/-277 seconds; kaolin ACTs were 605+/-182 and 499+65 seconds, which were consistently less than celite ACTs(p<0.01). At 10 minutes after protamine administration, celite ACT was 118+/-12 seconds and kaolin ACT was 142 56 seconds which was consistently more than celite ACT(p<0.05). CONCLUSIONS: We recommend the K-ACT rather than C-ACT when monitoring of heparin-induced anticoagulation in patients treated with high-dose aprotinin. It is also highly recommended that patients being added with aprotinin should receive the usual doses of heparin and that the ACT should be measured with kaolin as the activator.

Influence of Aprotinin on Kaolin and Celite on Activated Clotting Time in Cardiac Surgery / 대한마취과학회지

BACKGROUND: High-dose aprotinin appears to enhance the anticoagulant effects of heparin, as documented by increases in the activated clotting times (ACTs) during cardiopulmonary bypass. This increase of the ACT in the presence of aprotinin and heparin is due to the use of celite as surface activator. We compared celite and kaolin as surface activators for the measurement of the ACT in cardiac surgical patients treated with high dose aprotinin. METHODS: This study included 25 patients who were scheduled for coronary bypass graft surgery and reoperation of cardiac valvular surgery. The 2 million units of aprotinin were added to the pump prime of heart-lung machine. The dosage of heparin and protamine was 3 mg/kg respectively. Whole blood was sampled 10 minutes after induction, heparin administration, cardiopulmonary bypass(CPB), 10 minutes before the termination of CPB and 10 minutes after protamine administration. The ACT was measured with Hemochron 801 blood coagulation timer with 12 mg of either celite (C-ACT) or kaolin (K-ACT) used as surface activator. RESULTS: At 10 minutes after induction and heparin administration, celite and kaolin ACTs were l20+/-28, 541+/-247 seconds and 126+/-23, 559+/-267 seconds rcspectively. But 10 minutes after initiation of CPB and before the termination of CPB, celite ACTs were 941+/-238 and 787+/-277 seconds; kaolin ACTs were 605+/-182 and 499+65 seconds, which were consistently less than celite ACTs(p<0.01). At 10 minutes after protamine administration, celite ACT was 118+/-12 seconds and kaolin ACT was 142 56 seconds which was consistently more than celite ACT(p<0.05). CONCLUSIONS: We recommend the K-ACT rather than C-ACT when monitoring of heparin-induced anticoagulation in patients treated with high-dose aprotinin. It is also highly recommended that patients being added with aprotinin should receive the usual doses of heparin and that the ACT should be measured with kaolin as the activator.

Determination of promethazine and its metabolite in urine by solid——phase extraction with celite and UV derivative spectrophotometry / 中国法医学杂志

Objective To establish a simple and rapid method for extraction and determination promethazine and its metabolite in urine.Methods The urine was added to celite column and the elutions was effected with dichloromethane.The eluat was evaporated on a water bath at 50℃.The dry residue was redissolved with 3.0ml H2SO4 solution of 0.05mol/L,and then zinc dust was added,in order to make it reaction on the water bath of 100℃ for 3min.The promethazine and its metabolite concentration were determined with the second derivative UV spectrum.Resvlts The extraction rate was 90% for both promethazine and its metabolite.The linear range of determination was 0.5～5.0?g/ml.Conclusion The method for determinating promethazine and its metabolite in urine is simple,convenience,and with high extraction rate.