Effect of 3,6-anhydro-l-galactose on α-melanocyte stimulating hormone-induced melanogenesis in human melanocytes and a skin-equivalent model.

3,6-Anhydro-l-galactose (l-AHG) is a bioactive sugar that is a major component of agarose. Recently, l-AHG was reported to have anti-melanogenic potential in human epidermal melanocytes (HEMs) and B16F10 melanoma cells; however, its underlying molecular mechanisms remain unknown. At noncytotoxic concentrations, l-AHG has been shown to inhibit alpha-melanocyte-stimulating hormone-induced melanin synthesis in various cell models, including HEMs, melan-a cells, and B16F10 cells.

3,6-Anhydro-l-galactose, a rare sugar from agar, a new anticariogenic sugar to replace xylitol.

The significance for anticariogenic sugar substitutes is growing due to increasing demands for dietary sugars and rising concerns of dental caries. Xylitol is widely used as an anticariogenic sugar substitute, but the inhibitory effects of xylitol on Streptococcus mutans, the main cause of tooth decay, are exhibited only at high concentrations. Here, the inhibitory effects of 3,6-anhydro-l-galactose (AHG), a rare sugar from red macroalgae, were evaluated on S.

Enzymatic liquefaction of agarose above the sol-gel transition temperature using a thermostable endo-type β-agarase, Aga16B.

The main carbohydrate of red macroalgae is agarose, a heterogeneous polysaccharide composed of D-galactose and 3,6-anhydro-L-galactose. When saccharifying agarose by enzymes, the unique physical properties of agarose, namely the sol-gel transition and the near-insolubility of agarose in water, limit the accessibility of agarose to the enzymes. Due to the lower accessibility of agarose to enzymes in the gel state than to the sol state, it is important to prevent the sol-gel transition by performing the enzymatic liquefaction of agarose at a temperature higher than the sol-gel transition temperature of agarose.

Pretreatment and saccharification of red macroalgae to produce fermentable sugars.

Red macroalgae are currently considered as renewable resources owing to their high carbohydrate and low lignin and hemicellulose contents. However, utilization of red macroalgae has been limited owing to the lack of established methods for pretreatment and an effective saccharification system. Furthermore, marine red macroalgae consist of the non-favorable mixed sugars for industrial microorganisms.