Surfactant forms various self-organized structures in solution. Understanding the property of the self-organized structures leads to innovation in the quality and functionality of industrial products. In this context, effect of controlling HLB (hydrophile-lipophile balance) on preparation of sponge phase and increase in the amount of solubilized oil in microemulsion cubic phase were reported. In order to control HLB of anionic surfactant system which is highly hydrophilic, oleic acid was used as a cosurfactant. Oleic acid was revealed to have multiple effects, suppression of electrostatic repulsion of hydrophilic groups in addition to HLB control. It was concluded that addition of oleic acid is a novel method of control of HLB which would be widely applied to a variety of surfactant systems including the system with a restriction of components. Consequently, a novel environment-friendly detergent with high detergency was developed.

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Melanin, the end products of complex multistep transformations of L-tyrosine, are multifunctional biopolymers. Synthesis of melanin (melanogenesis) is a highly regulated and complex event occurring within melanocytes and melanoma cells. Although several factors have been known to participate in the regulation of melanogenesis, the precise mechanism (s) underlying the melanogenic process remains to be defined. On the other hand, phospholipase D (PLD) cleaves phosphatidylcholine in response to a variety of cell stimuli to generate phosphatidic acid which is thought to regulate a variety of cellular responses. Our recent study has demonstrated that PLD1 exerts a negative regulatory role in the melanogenic process by suppressing the expression of melanogenic enzymes leading to the decreased activity, probably through the PLD1/ mammalian target of rapamycin (mTOR) pathway.

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