ABSTRACT
(S) -3-Chloro-1-(2-thienyl)-1-propanol was synthesized by the asymmetric reduction of 3-chloro-1-(2-thienyl)propanone with liquid-core immobilized Candida pseudotropicalis 104. The optimum time was 28 h for the re-cultivation of immobilized cells. The optimum film solvent for the liquid-core capsule was 0.3 % chitosan (M (w) 1.0 × 10(5)). Conversion decreased with the increase of the liquid-core capsule diameter and with the addition of more substrates at the same reduction time. The immobilized cells show good reduction ability in a potassium phosphate buffer (pH 6.6~7.2). The material outside the spread speed of immobilized cells was not restricted when the shaking speed was higher than 160 r/min. Liquid-core immobilized cells can be reused 11 times. Compared with the batch reduction, the continuous reduction of 3-chloro-1-(2-thienyl)propanone in the membrane reactor with liquid-core immobilized cells as catalyst can relieve the inhibition from a high-concentration substrate. Conversion and enantiometric excess of (S)-3-chloro-1-(2-thienyl)-1-propanol reached 100 % and >99 % in a continuous reduction of 12 g/L 3-chloro-1-(2-thienyl)propanone for 10 days.
Subject(s)
Candida/cytology , Candida/metabolism , Propanols/chemistry , Propanols/metabolism , Thiophenes/chemistry , Thiophenes/metabolism , Bioreactors/microbiology , Buffers , Capsules , Cell Proliferation , Cells, Immobilized/metabolism , Chitosan/chemistry , Duloxetine Hydrochloride , Hydrogen-Ion Concentration , Membranes, Artificial , Molecular Weight , Oxidation-Reduction , Phosphates/chemistry , Potassium Compounds/chemistryABSTRACT
Fucoidan is a kind of sulfated polysaccharide with a variety of biological properties including anti-coagulation, lipid lowering and anti-tumor. Its anti-tumor mechanisms include immune regulation,induction of tumor cell apoptosis and inhibition of angiogenesis and so on.
ABSTRACT
Fucoidan is a kind of sulfated polysaccharide with a variety of biological activities.Chemical modification of polysaccharides can improve their bioactivities or make them produce new activities.In order to improve research of fucoidans and gain new polysaccharide drug with high bioactivity,this paper reviews preparative techniques and bioactivities of fucoidan derivatives,including low molecular weight fucoidan,desulfated fucoidan,oversulfated fucoidan,acetylated fucoidan,benzoylated fucoidan,phosphorylated fucoidan,aminated fucoidan and so on.
ABSTRACT
Objective To explore the changes of finger artery hemodynamics of patients with pulmonary heart disease, at the same time to search for the relationship with PaO_2.Methods We used American ACUSON128/xp10 and ATL5000 color Doppler ultrasound diagnostic instrument to detect double middle - finger artery hymodynamics items; VSMANX, VDMIN,TAMX , PI and RI. We used Danish ABL5 artery blood gas analysis to monitor PaO_2 and SaO_2.Results PaO_2 ,SaO_2, VSMAX,VDMIN ,TAMX,and PI in control group,pulmonary heart disease remission stage, active attack stage had significant difference (P
