Biodegradable Colour Polymeric Film (Starch-Chitosan) Development: Characterization for Packaging Materials

Biodegradable starch-based chitosan reinforced composite polymeric films were prepared by casting. The chitosan content in the films was varied from 20% to 80% (w/w). Tensile strength (TS) was improved significantly with the addition of chitosan but elongation at break (EB %) of the composites decreased. Tensile strength of the composites raised more with the addition of the acacia catechu content in the films varied from 0.05% to 0.2% (w/w). The better thermal stability of this prepared film was confirmed by thermo-gravimetric analysis. Structural characterization was done by Fourier transform infrared spectroscopy. Surface morphologies of the composites were examined by scanning electron microscope (SEM) which suggested sufficient homogenization of starch, chitosan and acacia catechu. Water uptake was found lower for final composites in comparison to starch/chitosan and chitosan films. The satisfactory rate of degradation in the soil is expected that the final composite film is within less than 6 months. The developed films intended to use as the alternative of synthetic non-biodegradable colored packaging films.

Phenolic compounds from the aqueous extract of Acacia catechu

From the aqueous extract of Acacia catechu,two new phenolic compounds（3R,4R）-3-（3,4-dihydroxyphenyl）-4-hydroxycy-clohexanone （1） and（4R）-5-（1-（3,4-dihydrophenyl）-3-oxobutyl）-dihydrofuran-2（3H）-one（2） were obtained.Their structures were determined on the basis of spectroscopic analysis.Free-radical scavenging activities of them were evaluated.

Pharmacokinetic interaction of Acacia catechu with CYP1A substrate theophylline in rabbits

OBJECTIVE:To investigate the effect of black catechu(BC) on the pharmacokinetics of theophylline(CYP1A2 substrate,with narrow therapeutic index)in rabbits.METHODS:In the present investigation the effect of BC on the pharmacokinetics of theophylline,a CYP1A2 substrate was determined.In the study,BC(264 mg/kg,p.o.) or saline(control group) was given to rabbits for 7 consecutive days and on the 8^(th)day theophylline(16 mg/kg) was administered orally one hour after BC or saline treatment.Blood samples were withdrawn at different time intervals(0.5,1,1.5,2,3,4,6,8,12,24 and 36 h) from the marginal ear vein.RESULTS:The pretreatment of rabbits with BC resulted in a significant increase in maximum blood concentration,time of peak concentration and area under the concentration time profile curve until last observation which was about 41.32%,35.71%and 15.03%,respectively.While decreases in clearance,volume of distribution,and half-life were observed.It is suggested that BC pretreatment decreases the CYP1 A metabolic activity leading to increase in bioavailability and decrease in oral clearance of theophylline,which may be due to inhibition of CYP1 A.CONCLUSION:BC can significantly alter theophylline pharmacokinetics in vivo possibly due to inhibition of CYP1 A and P-glycoprotein activity.Based on these results,precaution should be exercised when administering BC with CYP1 A substrate.