We describe the syntheses of novel sulfonated graft copolyimides and investigate their proton conductivity and gas permeability properties. The graft copolyimide membrane showed significantly higher proton conductivity exceeding that of Nafion, and the proton conductivity at 90 °C and 98% RH was 1.2 S/cm, more than 7 times that of Nafion. Furthermore, the oxygen permeability of the membrane was approximately one-eighth the value of Nafion and had a very excellent gas barrier property. The selectivity ratio calculated from the proton and oxygen transports of the graft copolyimide membrane was 66 times that determined in Nafion. We first demonstrated that the graft copolymer membrane could realize a high proton conductivity and low gas permeability of the fuel. Consequently, this material proved to be promising as a proton exchange membrane and may have potential applications for use in fuel cells.

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In order to evaluate the hypocholesterolemic effect of Lactobacillus casei subsp. casei TMC 0409 strain (TMC 0409), an isolate from 'Dadih', an Indonesian traditional fermented dairy food, Sprague-Dawley rats were fed cholesterol containing diets supplemented with fermented milk cultured with TMC 0409, skim milk and TMC 0409 lyophilized cells. No significant inhibitory effect was observed in the rats fed fermented milk and skim milk after 14 days feeding. But the increase of serum cholesterol was suppressed (36%) in the rats fed TMC 0409 lyophilized cells. Total cholesterol, HDL-cholesterol, triglyceride and phospholipid in serum, neutral steroid and bile acids in feces, cholesterol and triglyceride in liver were analyzed in the rats fed TMC 0409 cells after 14 days feeding. Total cholesterol and phospholipid were significantly decreased compared to those of control group (P<0.01), however HDL-cholesterol was significantly increased (P<0.05). Serum triglyceride was also decreased but the difference was not significant. From these results, the inhibition of increase of serum cholesterol in rats fed TMC 0409 cells was considered to have resulted from the reduction of LDL+VLDL-cholesterol. Meanwhile, the accumulation of triglyceride in the liver was inhibited significantly compared with the control group (P<0.05), and the excretion of bile acid in the feces was also enhanced significantly (P<0.01). These results imply that strain TMC 0409 can alter the serum cholesterol concentration, especially LDL+VLDL-cholesterol by enhancing the excretion of bile acids in the feces.