Dai Kitamoto

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Biosurfactants (BS) produced by various microorganisms show unique properties (e.g., mild production conditions, lower toxicity, higher biodegradability and environmental compatibility) compared to their chemical counterparts. The numerous advantages of BS have prompted applications not only in the food, cosmetic, and pharmaceutical industries but in(More)
Glyceric acid (GA), an unfamiliar biotechnological product, is currently produced as a small by-product of dihydroxyacetone production from glycerol by Gluconobacter oxydans. We developed a method for the efficient biotechnological production of GA as a target compound for new surplus glycerol applications in the biodiesel and oleochemical industries. We(More)
n-Alkanes ranging from C12 to C18 were converted into glycolipid biosurfactants, mannosylerythritol lipids (MEL), by resting cells of Pseudozyma (Candida) antarctica T-34. The highest yield (0.87 g g−1 substrate) was obtained from 6% (v/v) of n-octadecane after 7 days reaction. The amount of MEL reached 140 g l−1 by intermittent feeding of the substrate.
BSs (biosurfactants) produced by various micro-organisms show unique properties (e.g. mild production conditions, lower toxicity, higher biodegradability and environmental compatibility) compared with chemically synthesized surfactants. The numerous advantages of BSs have prompted applications not only in the food, cosmetic and pharmaceutical industries but(More)
Mannosylerythritol lipids (MEL), which are abundantly secreted by yeasts, are one of the most promising biosurfactants known. To obtain various types of MEL and to attain a broad range of applications for them, screening of novel producers was undertaken. Thirteen strains of yeasts were successfully isolated as potential MEL producers; they showed high(More)
Antiagglomeration effects of different surfactants on ice slurry formation were examined to improve the efficiency of an ice-water slurry system to be used for cold thermal storage. Among the chemical surfactants tested, a nonionic surfactant, poly(oxyethylene) sorbitan dioleate, was found to show a greater antiagglomeration effect on the slurry than(More)
Mannosylerythritol lipids (MELs) are glycolipid biosurfactants produced by Pseudozyma yeasts. They show not only the excellent interfacial properties but also versatile biochemical actions. In the course of MEL production from soybean oil by P. antarctica and P. rugulosa, some new extracellular glycolipids (more hydrophobic than the previously reported(More)
An ustilaginomycetous anamorphic yeast species isolated from the leaves of Saccharum officinarum (sugarcane) in Okinawa, Japan, was identified as a novel Pseudozyma species based on morphological and physiological aspects and molecular taxonomic analysis using the D1/D2 domains of the large subunit (26S) rRNA gene and the internal transcribed spacer 1(More)
A smut fungus Ustilago scitaminea NBRC 32730 on sugar cane (Saccharum) was found to accumulate a large amount of glycolipids in the culture medium. As a result of structural characterization, the main glycolipid was identified as MEL-B, 4-O-beta-(2',3'-di-O-alka(e)noyl-6'-O-acetyl-D-mannopyranosyl)-erythritol. The MEL-B was sufficiently produced from a(More)
Gluconobacter sp. NBRC3259 converted glycerol to glyceric acid (GA). The enantiomeric composition of the GA produced was a mixture of DL-forms with a 77% enantiomeric excess of D-GA. After culture conditions, such as initial glycerol concentration, types and amounts of nitrogen sources, and initial pH, were optimized, Gluconobacter sp. NBRC3259 produced(More)