Noriaki Kishimoto

Enzymatic synthesis of caffeic acid phenethyl ester analogues in ionic liquid

An efficient procedure for transesterification of methyl caffeate was developed to produce caffeic acid phenethyl ester analogues with Candida antarctica lipase B using an ionic liquid, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, as a solvent. The system provided 48.8mM 2-cyclohexylethyl caffeate and 46.9 mM 3-cyclohexylpropyl caffeate with conversion yields of 97.6% and 93.8%, respectively. Reusability of the system was investigated, and the yield of 4-phenylbutyl caffeate was increased from 30.4 to 45.7 mM when the transesterification was carried out under reduced pressure to remove a by-product, methanol. Additionally, we showed that both 2-cyclohexylethyl caffeate and 3-cyclohexylpropyl caffeate exhibit strong antiproliferative activities, which are comparable to that of 5-fluorouracil by MTT assay.

Two distinct pathways for the formation of hydroxy FA from linoleic acid by lactic acid bacteria

Twenty-three of 86 strains of lactic acid bacteria transformed linoleic acid into hydroxy FA. Two distinct conversion pathways were in operation. Two strains of Lactobacillus acidophilus and a strain of Pediococcus pentosaceus produced 13(S)-hydroxy-9-octadecenoic acid [13(S)-OH 18∶1] and 10,13-dihydroxyoctadecanoic acid (10,13-OH 18∶0) as main and minor products, respectively, whereas 13 strains, including L. casei subsp. casei, L. paracasei subsp, paracasei, L. rhamnosus, L. lactis subsp. cremoris, and Streptococcus salivarius subsp. thermophilus produced 10-hydroxy-12-octadecenoic acid (10-OH 18∶1). Seven strains of L. plantanum converted linoleic acid to 10-hydroxyoctadecanoic acid (10-OH 18∶0) through 10-OH 18∶1 Linoleic acid at 2 g/L was converted by L. acidophilus LFO13951T to 1.3 g of 13(S)-OH 18∶1 and 0.09 g of 10,13-OH 18∶0 in 7 d. Lactobacillus paracasei subsp. paracasei JCM 1111 produced 10-OH 18∶1 in 91% yield, and L. plantarum JCM 8341, 10-OH 18∶0 in 59% yield from linoleic acid (2 g/L) under optimal conditions. To our knowledge, this is the first report on the production of 13(S)-OH 18∶1 by lactic acid bacteria other than ruminal bacteria, and of 10,13-OH 18∶0 by any bacteria.

Recovery of Sterols as Fatty Acid Steryl Esters from Waste Material After Purification of Tocopherols

Tocopherols are purified industrially from soybean oil deodorizer distillate by a process comprising distillation and ethanol fractionation. The waste material after ethanol fractionation (TC waste) contains 75% sterols, but a purification process has not yet been developed. We thus attempted to purify sterols by a process including a lipase-catalyzed reaction. Candida rugosa lipase efficiently esterified sterols in TC waste with oleic acid (OA). After studying several factors affecting esterification, the reaction conditions were determined as follows: ratio of TC waste/OA, 1∶2 (wt/wt); water content, 30%; amount of lipase, 120 U/g-reaction mixture; temperature, 40°C. Under these conditions, the degree of esterification reached 82.7% after 24 h. FA steryl esters (steryl esters) in the oil layer were purified successfully by short-path distillation (purity, 94.9%; recovery, 73.1%). When sterols in TC waste were esterified with FFA originating from olive, soybean, rapeseed, safflower, sunflower, and linseed oils, the FA compositions of the steryl esters differed somewhat from those of the original oils: The content of saturated FA was lower and that of unsaturated FA was higher. The m.p. of the steryl esters synthesized (21.7–36.5°C) were remarkably low compared with those of the steryl esters purified from high-b.p. soybean oil deodorizer distillate substances (56.5°C; JAOCS 80, 341–346, 2003). The low-m.p. steryl esters were soluble in rapeseed oil even at a final concentration of 10%.

Antimicrobial properties and mechanism of volatile isoamyl acetate, a main flavour component of Japanese sake (Ginjo-shu)

To evaluate the antimicrobial properties of the main Ginjo‐flavour components of sake, volatile isoamyl acetate and isoamyl alcohol.

One-pot enzymatic synthesis of docosahexaenoic acid-rich triacylglycerols at the sn-1(3) position using by-product from selective hydrolysis of tuna oil

Docosahexaenoic acid (DHA)-rich oil has been industrially produced by selective hydrolysis of tuna oil with a lipase that acts weakly on DHA. The free fatty acids (FFAs) generated in this process as by-products contain a high DHA concentration (46wt%) but are treated as industrial waste. This study attempted to reuse these by-product FFAs using a one-pot process, and succeeded in producing triacylglycerols (TAGs) through the esterification of the by-product FFAs with glycerol using immobilized Rhizomucor miehei lipase. Regiospecific analysis of the resulting TAGs showed that the content of DHA at the sn-1(3) position (51.7mol%) was higher than the content of DHA at the sn-2 position (17.3mol%). The DHA distribution in TAGs synthesized in this study was similar to the DHA distribution in TAGs from seal oil.

Draft Genome Sequence of the Basidiomycetous Fungus Flammulina velutipes TR19.

ABSTRACT Here, we report the draft genome sequence of Flammulina velutipes TR19, which was newly isolated from commercial strains in Japan. The genes related to fruiting body formation in the basidiomycete were identified by whole-genome analysis.

Complete genome sequence of the xylan-degrading subseafloor bacterium Microcella alkaliphila JAM-AC0309

Here we report the complete genome sequence of Microcella alkaliphila JAM-AC0309, which was newly isolated from the deep subseafloor core sediment from offshore of the Shimokita Peninsula of Japan. An array of genes related to utilization of xylan in this bacterium was identified by whole genome analysis.

Draft Genome Sequence of the Ionic Liquid-Tolerant Bacterium Bacillus amyloliquefaciens CMW1

ABSTRACT Here, we report the draft genome sequence of an ionic liquid-tolerant bacterium, Bacillus amyloliquefaciens CMW1, which is newly isolated from a Japanese fermented soybean paste. The genome sequence will allow for a characterization of the molecular mechanism of its ionic liquid tolerance.

Draft Genome Sequence of a Deep-Sea Bacterium, Bacillus niacini Strain JAM F8, Involved in the Degradation of Glycosaminoglycans

ABSTRACT Here, we report the draft genome sequence of Bacillus niacini JAM F8, which was newly isolated from deep-sea sediment at a depth of 2,759 m from the Izu-Ogasawara Trench. An array of genes related to degradation of glycosaminoglycans in this bacterium was identified by whole-genome analysis.

Degradation of ionic liquids by a UV/H2O2 process and CMCase from novel ionic liquid-tolerant alkaliphilic Nocardiopsis sp. SSC4

ABSTRACT We demonstrated the degradation of two ionic liquids (1-butyl-3-methylimidazolium chloride, [BMIM]Cl, and 1-ethylpyridinium bromide, [EtPy]Br) that are useful for the solubilization of wood components. [BMIM]+ and [EtPy]+ were detected by thin-layer chromatography (TLC) and electrospray ionization–mass spectrometry (ESI-MS). [BMIM]+ was harder to degrade than [EtPy]+. Ultraviolet (UV) irradiation with 0.2% (v/v) H2O2 for 16 h degraded 1 mmol/L [BMIM]+, whereas UV irradiation alone degraded 1 mmol/L [EtPy]+. Additionally, we isolated an ionic liquid-tolerant alkaliphilic actinomycete, Nocardiopsis sp. SSC4. Strain SSC4 produced carboxymethylcellulase (CMCase) in the presence of 1.0% (v/v, 48.1 mmol/L) 1-ethyl-3-methylimidazolium trifluoromethanesulphonate ([EMIM]CF3SO3), which is useful for the extraction of cellulose-rich materials from wood. In the case of strain SSC4, CMCase was inducibly synthesized by more than 0.5% CMC. The addition of 0%–1.0% tryptone or 0%–2.0% yeast extract decreased the CMCase activity in a concentration-dependent manner. After cultivation of strain SSC4 with 1.0% (w/v) CMC medium (pH 9.0) for 48 h at 37 °C, the culture supernatant exhibited CMCase activity at 0.03 U/mg. The optimum reaction temperature of CMCase was 45 °C. CMCase was stable up to 37 °C for 20 h incubation. The degradation characteristics of [BMIM]+ and [EtPy]+ and the activity of CMCase in the presence of [EMIM]CF3SO3 may be useful for the development of a bioconversion system for biomass resources.