Orienting functional proteins is essential for construction of a biochip in the future. In this article, general methods for orienting photosensitive proteins on a solid substrate are reviewed. Then a rational method to control the orientation of an extremely stable light sensitive retinal protein, bacteriorhodopsin, by two kinds of bispecific (BS) antibodies with different binding sites is described. The confirmation of the orientation and uniformity of bacteriorhodopsin by immuno-gold labeling techniques is also discussed.

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Partially dicarboxylated polysaccharides were prepared using starch from corn, sago and tapioca and comparison was made of their biodegradability, hydrolytic degradability and builder performance in detergent formulations. The biodegradability of dicarboxylated starch sodium salt (DC-starch) depended on the dicarboxylation degree. DC-starch containing more than 7585 mol% unreacted glucopyranose groups in the polymer chain showed excellent biodegradation. DC-starch with high dicarboxylation degree was resistant to biodegradation but showed good builder performance in detergent formulation. Among DC-starches from corn, sago and tapioca starches, hydrolytic degradability and builder performance were essentially the same.

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Glycosphingolipids containing two gala-6 core series were shown to be present in the leech, Hirudo nipponia. Their structures were determined as Gal β1-1Cer, Galα1-6Gal β1-1Cer, Galα1-6Galα1-6Galβ1-Cer and Galα1-6Galα1-6Galα1-6Galβ1-Cer as neutral glycolipids and cholinephosphate→6Galβ1-1Cer and cholinephosphate→6Galβ1-6Galβ1-1Cer as amphoteric glycolipids, based on the results of compositional and methylation analyses and exogalactosidase treatments. Ceramides mainly contained C_{16 : 0}, C_{18 : 0}, C_{22 : 0} and C_{24 : 0} fatty acids and dihydroxy- (C_{18 : 1}, C_{19 : 1} and C_{22 : 3}) and trihydroxy- (C_{18 : 0} and C_{19 : 0}) sphingoids. The authors tentatively designated the disaccharide structure, Galα1-6Gal, as the “isoneogala-series”, which may represent a new type of glycosphingolipid core series.

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During the screening among the oil decomposing microorganisms which had a low decomposing ability for docosahexaenoic acid (DHA), we isolated a strain identified as Candida famata US-238 by Japan Food Research Laboratories. The optimal cultivation conditions of this strain for relatively concentrating DHA from fish oils were examined. Furthermore, we investigated the feasibility for the mass production of the oil with high DHA concentration by this strain in the jar fermenter. An oil containing about 50 per cent DHA was obtained.

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Modification of normal mouse IgG and mouse anti-DNP (dinitrophenol) monoclonal antibody with dodecyl glycidyl phosphate (C₁₂-AGP) and hexadecyl glycidyl phosphate (C₁₆-AGP) was conducted by reactions of the epoxy ring of AGP with active hydrogen groups (-NH₂ and -SH) of the antibodies in dilute borate buffer solution (pH=9.0). Analysis of free-NH₂ groups of the antibodies before and after modification by the TNBS method indicated the -NH₂ groups of the antibodies to have undergone modification by approximately 15%. Specific binding affinity of the modified anti-DNP antibody toward DNP was assayed by ELISA. The binding activity of the antibody to DNP molecules could be detected even after modification. AGP is thus shown to be a novel effective modifier for proteins. Antibody bearing liposomes were prepared with the C₁₆-AGP modified anti-DNP antibody by detergent dialysis. The antibodies introduced onto the surface of liposomes by this method retained their original antigenic specificity and capacity to bind to antigens.

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Thermotropic phase transitions of octadecyldimethylamine hydrochloride (OHC) and dioctadecylmethylamine hydrochloride (DOHC) -water systems were studied by fourier transform infrared spectroscopy. In the OHC system, coagel-gel and gel-liquid crystalline phase transitions occurred at 22 and 50°C, respectively. In the DOHC-water system, coagel and liquid crystalline states were confirmed present but not the gel state. In the coagel phase, methylene chains took on a trans-zigzag conformation with the hydrophilic part remaining in a fixed state. In the gel phase, rotational motion of the methylene chains about the chain axis was noted in the hexagonal lattice, and the hydrophilic part was in a fused state. In the liquid crystalline phase, hydrophobic and hydrophilic parts were in fused states.

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Lipase catalyzed transesterification between tributyrylglycerol (1) and 2-alkanols (2) has been studied at 30°C using Pseudomonas cepacia and porcine pancreatic lipases (PCL and PPL), six alcohols, and five kinds of organic solvents. The kinetic resolution data were quantitatively analyzed for resolving the alcohol (ee≥0.95) from the racemate, (RS) - (2). The enantiomeric ratios (E values) of PPL catalysis were larger than those of PCL in all cases. E differed according to solvent and the structure of (2). A reversibility of the transesterification was examined : the equilibrium constants (K) were 0.0150.038 and decreased with increase in the hydrophobicity of solvent. The resolution of (R) - (2) (ee ≥0.95) from (RS) - (2) was thus carried out and the measured optical purity of (R) - (2) was in agreement with that expected from E and K. The resolution of (S) - (2) appeared to be strongly affected by K, i.e., the reverse reaction.

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Cationic surfactants containing twotail-chains with a ferrocenyl group at each tail end ina molecule, {Fc (CH₂) _n} ₂N⁺ (CH₃) ₂Br- (n-BFDMA; n=5 and 11), were prepared from ω-bromoalkanoicacid through five reaction steps. The intermediates and the products were characterized by use of IR, ¹H NMR, Mass spectra, and elemental analysis. Aggregation states of 11-BFDMA changed drastically by the oxidation of ferrocenyl groups. Moreover, the spontaneous vesicle formation was observed in the aqueous solution of reduced 11-BFDMA above the critical micelle concentration.

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A method for the convenient quantitative determination of hydrogenated phosphatidylcholine (PC), for use as a cosmetic ingredient, was developed by using high performance liquid chromatography (HPLC), equipped with a silica gel column (Senshu Scientific, AQUASIL SS-352 N) and a UV detector (205 nm). This column possesses not only the usual properties of a silica gel column but can accommodate a mobile phase containing water. In this study, the solution used as the mobile phase was methanol/0.01 M potassium dihydrogen-phosphate, citric acid buffer (pH 3.0) (95/5, by vol.) at 1.0 mL/min. Hydrogenated PC could be detected rapidly, and there was no interfering peak. Non-hydrogenated PC was also present. Linear response was noted for hydrogenated and non-hydrogenated PC at 1004000 μg/mL and 52000 μg/mL, respectively. Minimum quantification was 50 and 1 μg/mL for these samples. Theretention time of hydrogenated PC was dependent on carbon chain length of fatty acid in PC molecules.
Other phospholipids such as phosphatidylinositol (PI), phosphatidylethanolamine (PE), lysophosphatidylcholine (LPC), and sphingomyelin (SPH) could also be determined independently by this method.

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A fungus was isolated which produced xylan-degrading enzymes effective for the synthesis of alkyl β-xylosides from xylan and alcohols in a single step operation. Xylan (10 g) and 1-heptanol (150 mL) were added to culture broth (350 mL) of the isolated Penicillium sp. 9203, and the reaction mixture was chromatographed on a activated carbon column. The succesive elutions were done with 20% and 30% (vol/vol) 1-propanol solution. Crystal of heptyl β-xyloside (0.8 g) was obtained from the 30% (vol/vol) 1-propanol fraction.

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