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Improving solubility of lipophilic drugs: Enzymatic synthesis of drug-saccharide derivatives in nonaqueous media
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Abstracts / Journal of Biotechnology 136S (2008) S506–S518
foil impeller. However, there was significant effect to the mixing improvement on the enzyme particles distribution by using 2 impellers system with spacing of 30 mm even at lower agitation speed (≤200 rpm). High stability of Novozym 435 was observed even in the presence of shear forces on the enzyme particles due to the mechanical agitation speed. Wax ester reaction mixture in STR follows Newtons’ law due to the linear relation between the shear stress () and shear rate (d/dy) (Gogate et al., 2000). The process was successfully carried out to the highest amount of wax ester that can be produced in 2 L STR whereby, the production and productivity of oleyl oleate were improved from 295.39 g/L/h to 705.76 g/L/h and 310.16 g/h to 952.78 g/h, respectively. References Gogate, P.R., Beenackers, A.A.C.M., Pandit, A.B., 2000. Multiple-impeller systems with a special emphasis on bioreactors: a critical review. Biochem. Eng. J., 109–144. Tatterson, G.B., 1994. Scale-up and Design for Industrial Mixing Processes. McGrawHill, New York.
doi:10.1016/j.jbiotec.2008.07.643
bic drugs, enhancing oral bioavailability and promoting new drugs development. References Lipinski, C.A., Lombardo, F., Dominy, B.W., Feeney, P.J., 2001. Experimental and computational approaches to estimate solubility and permeability in drug discovery and development settings. Adv. Drug Deliv. Rev. 46, 3–26. Miura, Y., Ikeda, T., Kobayashi, K., 2003. Chemoenzymatically synthesized glycoconjugate polymers. Biomacromolecules 4, 410–415.
doi:10.1016/j.jbiotec.2008.07.644 V7-P-022 Preparation technology of Bifidobacterium bifidum freeze-dried powder and microencapsulation and study on its characters Min Zhao ∗ , Fan Zhang, Wei Wang, Xingdong Wei College of Life Sciences, Northeast Forestry University, Harbin 150040, China E-mail address: [email protected] (M. Zhao).
V7-P-021 Improving solubility of lipophilic drugs: Enzymatic synthesis of drug-saccharide derivatives in nonaqueous media Jing Quan 1,2 , Yan Zheng 1 , Bo Jiang 1 , Limin Zhu 1,∗ , Xianfu Lin 2,∗ 1
College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620, China 2 Department of Chemistry, Zhejiang University, Hangzhou, 310027, China E-mail address: [email protected] (L. Zhu).
In recent years, most of compounds with powerful pharmacological activity, drug candidates currently in the developmental stage often exhibit high lipophilicity and limited water solubility (Lipinski et al., 2001). The lipophilic drugs show the poor gastrointestinal absorption, low oral bioavailability and poor solubility that seriously restrict in vitro, in situ, and in vivo absorption studies. The conjugation of saccharides and drugs offers a lot of opportunity for preparing drug derivatives with bioactive moieties, enriching the categories of pharmaceuticals and improving drug bioavailability (Miura et al., 2003). In particularly, the relationship between the solubility of drug-saccharide conjugates and the structure of parent drugs is still a valuable and interesting topic, which would support available information to further investigate the therapeutic benefit of drugs and their derivatives. In this study, glucose and five parent drugs (chlorphenesin, mephenesin, guaifenesin, propranolol and clorprenaline) were chosen as substrates and drug-saccharide conjugates were obtained by enzymatic synthesis methods Firstly, drug vinyl esters were obtained by adding optimal enzyme to organic solvents containing drug and divinyl dicarboxylates kept at 50 ◦ C and shaken at 250 rpm, respectively. Then, drug vinyl esters and glucose, alkaline protease from Bacillus subtilis and pyridine was kept at 50 ◦ C with 250 rpm. The products were isolated by silica gel column chromatography. Analytical HPLC was performed with a reversed-phase Shim-Pack VP-ODS column. The distribution coefficient (D7.4 ) of the drugs and their glycolipids were determined the respective compound in an equal volume of n-octanol and phosphate buffer (pH 7.4). The results indicated that the relative solubility improved ranged from 9.4 mg mL−1 to 26.4 mg mL−1 for five parent drugs, and the drugs with more hydrophobic structures provided lower solubilities of drug-saccharide glycolipids. It will be an attractive strategy for improving the water solubility of hydropho-
In order to increase the viable count of Bifidobacterium bifidum freeze-dried powder, three kinds of the preparation technology were researched. The methods were as follows, freeze-dry after using the medium of milk fermentation B. bifidum, freeze-dry with mannitol and skim milk powder as cryoprotectants after using the PTYG medium culture B. bifidum, and using the gelatin and skim milk powder as cryoprotectants. The viable count of B. bifidum was large for the second method, and it was stable in gastrointestinal environment. The second method was tested for the industrial production, and the preparation technology was obtained. The result showed the highest amount of viable B. bifidum in the freezedried powder could reach 1010 cfu g−1 ; the viable count could keep 109 cfu g−1 when freeze-dried powder were disposed in gastrointestinal environment (Arnaud and Christophe, 2003). In addition, we research the emulsion method of double-layer B. bifidum microcapsules that gelatin, pectin, alginate sodium, calcium chloride and chitosan were used for the principal wall material in production. The result showed the particles were 10–30 m, the amount of active B. bifidum were more than 109 cfu g−1 and the embed ratio could reach 82.24% (Wen et al., 2003). When microcapsules were disposed with artificial gastric solution and bile solution, the amounts of viable B. bifidum in microcapsules were more than 108 cfu g−1 . It indicated it had the high acid tolerance. When disposed with artificial intestinal solution for 15 min, all microcapsules were nearly disintegrated and the release ratio reached 95.81%. Classic accelerating test showed that the B. bifidum microcapsules had better stability of storage (Desmond et al., 2002), more than 108 cfu g−1 bacteria remained alive after one-year storage at 25 ◦ C. References Arnaud, P., Christophe, L., 2003. Effects of micronization on viability and thermotolerance of probiotic freeze-dried cultures. Int. Dairy J. 13, 455–462. Wen, C.L., Hung, C.H., Cheng, C.C., 2003. Viability of microencapsulated bifidobacteria in simulated gastric juice and bile solution. Int. J. Food Microbiol. 86, 293–301. Desmond, C., Ross, R.P., Callaghan, E.O., 2002. Improved survival of Lactobacillus paracasei NFBC 338 in spray-dried powders containing gum acacia. J. Appl. Microbiol. 93, 1003–1005.
doi:10.1016/j.jbiotec.2008.07.645
Abstracts / Journal of Biotechnology 136S (2008) S506–S518
foil impeller. However, there was significant effect to the mixing improvement on the enzyme particles distribution by using 2 impellers system with spacing of 30 mm even at lower agitation speed (≤200 rpm). High stability of Novozym 435 was observed even in the presence of shear forces on the enzyme particles due to the mechanical agitation speed. Wax ester reaction mixture in STR follows Newtons’ law due to the linear relation between the shear stress () and shear rate (d/dy) (Gogate et al., 2000). The process was successfully carried out to the highest amount of wax ester that can be produced in 2 L STR whereby, the production and productivity of oleyl oleate were improved from 295.39 g/L/h to 705.76 g/L/h and 310.16 g/h to 952.78 g/h, respectively. References Gogate, P.R., Beenackers, A.A.C.M., Pandit, A.B., 2000. Multiple-impeller systems with a special emphasis on bioreactors: a critical review. Biochem. Eng. J., 109–144. Tatterson, G.B., 1994. Scale-up and Design for Industrial Mixing Processes. McGrawHill, New York.
doi:10.1016/j.jbiotec.2008.07.643
bic drugs, enhancing oral bioavailability and promoting new drugs development. References Lipinski, C.A., Lombardo, F., Dominy, B.W., Feeney, P.J., 2001. Experimental and computational approaches to estimate solubility and permeability in drug discovery and development settings. Adv. Drug Deliv. Rev. 46, 3–26. Miura, Y., Ikeda, T., Kobayashi, K., 2003. Chemoenzymatically synthesized glycoconjugate polymers. Biomacromolecules 4, 410–415.
doi:10.1016/j.jbiotec.2008.07.644 V7-P-022 Preparation technology of Bifidobacterium bifidum freeze-dried powder and microencapsulation and study on its characters Min Zhao ∗ , Fan Zhang, Wei Wang, Xingdong Wei College of Life Sciences, Northeast Forestry University, Harbin 150040, China E-mail address: [email protected] (M. Zhao).
V7-P-021 Improving solubility of lipophilic drugs: Enzymatic synthesis of drug-saccharide derivatives in nonaqueous media Jing Quan 1,2 , Yan Zheng 1 , Bo Jiang 1 , Limin Zhu 1,∗ , Xianfu Lin 2,∗ 1
College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, 201620, China 2 Department of Chemistry, Zhejiang University, Hangzhou, 310027, China E-mail address: [email protected] (L. Zhu).
In recent years, most of compounds with powerful pharmacological activity, drug candidates currently in the developmental stage often exhibit high lipophilicity and limited water solubility (Lipinski et al., 2001). The lipophilic drugs show the poor gastrointestinal absorption, low oral bioavailability and poor solubility that seriously restrict in vitro, in situ, and in vivo absorption studies. The conjugation of saccharides and drugs offers a lot of opportunity for preparing drug derivatives with bioactive moieties, enriching the categories of pharmaceuticals and improving drug bioavailability (Miura et al., 2003). In particularly, the relationship between the solubility of drug-saccharide conjugates and the structure of parent drugs is still a valuable and interesting topic, which would support available information to further investigate the therapeutic benefit of drugs and their derivatives. In this study, glucose and five parent drugs (chlorphenesin, mephenesin, guaifenesin, propranolol and clorprenaline) were chosen as substrates and drug-saccharide conjugates were obtained by enzymatic synthesis methods Firstly, drug vinyl esters were obtained by adding optimal enzyme to organic solvents containing drug and divinyl dicarboxylates kept at 50 ◦ C and shaken at 250 rpm, respectively. Then, drug vinyl esters and glucose, alkaline protease from Bacillus subtilis and pyridine was kept at 50 ◦ C with 250 rpm. The products were isolated by silica gel column chromatography. Analytical HPLC was performed with a reversed-phase Shim-Pack VP-ODS column. The distribution coefficient (D7.4 ) of the drugs and their glycolipids were determined the respective compound in an equal volume of n-octanol and phosphate buffer (pH 7.4). The results indicated that the relative solubility improved ranged from 9.4 mg mL−1 to 26.4 mg mL−1 for five parent drugs, and the drugs with more hydrophobic structures provided lower solubilities of drug-saccharide glycolipids. It will be an attractive strategy for improving the water solubility of hydropho-
In order to increase the viable count of Bifidobacterium bifidum freeze-dried powder, three kinds of the preparation technology were researched. The methods were as follows, freeze-dry after using the medium of milk fermentation B. bifidum, freeze-dry with mannitol and skim milk powder as cryoprotectants after using the PTYG medium culture B. bifidum, and using the gelatin and skim milk powder as cryoprotectants. The viable count of B. bifidum was large for the second method, and it was stable in gastrointestinal environment. The second method was tested for the industrial production, and the preparation technology was obtained. The result showed the highest amount of viable B. bifidum in the freezedried powder could reach 1010 cfu g−1 ; the viable count could keep 109 cfu g−1 when freeze-dried powder were disposed in gastrointestinal environment (Arnaud and Christophe, 2003). In addition, we research the emulsion method of double-layer B. bifidum microcapsules that gelatin, pectin, alginate sodium, calcium chloride and chitosan were used for the principal wall material in production. The result showed the particles were 10–30 m, the amount of active B. bifidum were more than 109 cfu g−1 and the embed ratio could reach 82.24% (Wen et al., 2003). When microcapsules were disposed with artificial gastric solution and bile solution, the amounts of viable B. bifidum in microcapsules were more than 108 cfu g−1 . It indicated it had the high acid tolerance. When disposed with artificial intestinal solution for 15 min, all microcapsules were nearly disintegrated and the release ratio reached 95.81%. Classic accelerating test showed that the B. bifidum microcapsules had better stability of storage (Desmond et al., 2002), more than 108 cfu g−1 bacteria remained alive after one-year storage at 25 ◦ C. References Arnaud, P., Christophe, L., 2003. Effects of micronization on viability and thermotolerance of probiotic freeze-dried cultures. Int. Dairy J. 13, 455–462. Wen, C.L., Hung, C.H., Cheng, C.C., 2003. Viability of microencapsulated bifidobacteria in simulated gastric juice and bile solution. Int. J. Food Microbiol. 86, 293–301. Desmond, C., Ross, R.P., Callaghan, E.O., 2002. Improved survival of Lactobacillus paracasei NFBC 338 in spray-dried powders containing gum acacia. J. Appl. Microbiol. 93, 1003–1005.
doi:10.1016/j.jbiotec.2008.07.645