Novel proton-conducting polymer electrolyte membranes have been prepared from bacterial cellulose by incorporation of phosphoric acid (H3PO4/BC) and phytic acid (PA/BC). H3PO4 and PA were doped by immersing the BC membranes directly in the aqueous solution of H3PO4 and PA, respectively. Characterizations by FT-IR, TG, TS and AC conductivity measurements were carried out on the membrane electrolytes consisting of different H3PO4 or PA doping level. The ionic conductivity showed a sensitive variation with the concentration of the acid in the doping solution through the changes in the contents of acid and water in the membranes. Maximum conductivities up to 0.08 S cm-1 at 20oC and 0.11 S cm -1 at 80oC were obtained for BC membranes doped from H3PO4 concentration of 6.0 mol L-1 and, 0.05 S cm-1 at 20oC and 0.09 S cm -1 at 60oC were obtained for BC membranes doped from PA concentration of 1.6 mol L-1. These types of proton-conducting membranes share not only the good mechanical properties but also the thermal stability. The temperature dependences of the conductivity follows the Arrhenius relationship at a temperature range from 20 to 80oC and, the apparent activation energies (Ea) for proton conduction were found to be 4.02 kJ mol-1 for H3PO4/BC membrane and 11.29 kJ mol-1 for PA/BC membrane, respectively. In particular, the membrane electrode assembly fabricated with H3PO4/BC and PA/BC membranes reached the initial power densities of 17.9 mW cm-2 and 23.0 mW cm-2, which are much higher than those reported in literatures in a real H2/O2 fuel cell at 25oC.

细菌纤维素是一种新型微生物合成材料，在食品、造纸、纺织、生物医药、声学器材振动膜和功能复合材料等方面均有很好的应用前景。细菌纤维素发酵培养基（尤其碳源）的成本是现今制约细菌纤维素推广应用的主要因素之一。甘露醇、果糖和葡萄糖等合成培养基所用碳源因其价格较高仅适用于实验室研究和小型发酵生产，规模化生产细菌纤维素的潜在原料应是一些量大价低的天然原料，包括水果类原料、糖质原料、低值淀粉类原料和废弃纤维素类原料等。木质纤维素原料是最具发展潜力的细菌纤维素碳源，也是细菌纤维素产业的根本出路，但目前存在一些技术瓶颈，制约了其开发利用，是一远期战略目标。文章简要介绍了细菌纤维素的基本情况，系统阐述了国内外发酵生产细菌纤维素原料的研究进展，展望了今后的发展趋势。

Optimization of cultivation conditions for lipase production and the preparation of a specific lipase catalyzing the hydrolysis of polyethylene terephthalate (PET) by Aspergillus oryzae CCUG 33812 as well as modification of PET fabrics by the enzyme were investigated. The lipase activity produced by the fungus after addition of olive oil was not efficient in changing the properties of PET samples. In order to obtain lipase activity directed towards hydrolysis of PET, two derivatives of terephthalic acid (TPA), namely diethyl p-phthalate (DP) and bis(2-hydroxyethyl) terephthalate (BHT), and PET short fibers were used as inducers. The results showed that BHT was the best inducer. The BHT-induced extracellular lipase could catalyze hydrolysis of the PET model substrate diethyl p-phthalate. The formation of new carboxyl groups is consistent with the increase in K/S values of dyed PET fabrics after the enzymatic treatment. Additionally, treatment with the BHT-induced lipase resulted in increased moisture regain and weight loss of PET fiber/fabric, while the water contact angle and the static half decay time decreased slightly. This indicates that hydrophilicity and anti-static ability were improved after the treatment with the BHT-induced lipase. Compounds that were solubilized by the enzymatic treatment were analyzed by spectrophotometry and high performance liquid chromatography with UV detection. Both analyses indicated that hydrolysis of PET occurred and that products were formed due to the catalytic action of the BHT-induced enzyme, however, no significant changes in UV absorbance and no new peaks were found in HPLC-UVD analyses of reaction mixtures with olive oil-induced lipase or PET-induced lipase. This investigation has resulted in detailed procedures for production of PET-hydrolyzing lipase by A. oryzae and is the first report regarding the successful use of BHT as an inducer for the enzyme production.