Two novel glucosides of 6-gingerdiol were isolated from fresh ginger (Zingiber officinale Roscoe). Their structures were determined as 1-(4-O-beta-D-glucopyranosyl-3-methoxyphenyl)-3,5-dihydroxydecane (1) and 5-O-beta-D-glucopyranosyl-3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)deca ne (2) by HRFAB-MS and NMR analyses, and the absolute configurations of both aglycons were identified as (3S,5S) by a comparison with synthetic compounds. After incubating these glucosides with acetone powder prepared from fresh ginger, they were confirmed to have been hydrolyzed to 6-gingerdiol by HPLC. This result suggests that these glucosides are the precursors or intermediates of 6-gingerdiol. To recognize their function, their antioxidative activities were investigated and compared to that of their aglycon, 6-gingerdiol, by a linoleic acid model system and by their DPPH radical-scavenging ability. Although 1 did not indicate any activity, 2 had as strong activity as the aglycon in both measurements.

We investigated the components of ginger that are involved in increasing body temperature. Gingerols ([6,8,10]-gingerols) and shogaols ([6,8,10]-shogaols) having different alkyl carbon chain lengths were targeted. All the gingerols and shogaols increased intracellular calcium concentration in rat transient receptor potential vanilloid subtype 1 (TRPV1)-expressing HEK293 cells via TRPV1. In this regard, the shogaols were more potent than the gingerols. Aversive responses were induced by [6]-, [10]-gingerol, and [6]-shogaol (5 mmol/l) in rats when these compounds were applied to the eye; however, no response was observed in response to [10]-shogaol (5 and 10 mmol/l). [10]-Shogaol induced nociceptive responses via TRPV1 in rats following its subcutaneous injection into the hindpaw; the pungent compound capsaicin (CAP) and [6]-shogaol were observed to have similar effects. Moreover, adrenal catecholamine secretion, which influences energy consumption, was promoted in rats in response to [6]- and [10]-gingerols and [6]- and [10]-shogaols (1.6 micromol/kg, i.v.). [10]-Shogaol-induced adrenaline secretion was inhibited by administration of capsazepine, a TRPV1 antagonist. In conclusion, gingerols and shogaols activated TRPV1 and increased adrenaline secretion. Interestingly, [10]-shogaol is the only nonpungent compound among the gingerols and shogaols, suggesting its usefulness as a functional ingredient in food.

We investigated the components of ginger that are involved in increasing body temperature. Gingerols ([6,8,10]-gingerols) and shogaols ([6,8,10]-shogaols) having different alkyl carbon chain lengths were targeted. All the gingerols and shogaols increased intracellular calcium concentration in rat transient receptor potential vanilloid subtype 1 (TRPV1)-expressing HEK293 cells via TRPV1. In this regard, the shogaols were more potent than the gingerols. Aversive responses were induced by [6]-, [10]-gingerol, and [6]-shogaol (5 mmol/l) in rats when these compounds were applied to the eye; however, no response was observed in response to [10]-shogaol (5 and 10 mmol/l). [10]-Shogaol induced nociceptive responses via TRPV1 in rats following its subcutaneous injection into the hindpaw; the pungent compound capsaicin (CAP) and [6]-shogaol were observed to have similar effects. Moreover, adrenal catecholamine secretion, which influences energy consumption, was promoted in rats in response to [6]- and [10]-gingerols and [6]- and [10]-shogaols (1.6 micromol/kg, i.v.). [10]-Shogaol-induced adrenaline secretion was inhibited by administration of capsazepine, a TRPV1 antagonist. In conclusion, gingerols and shogaols activated TRPV1 and increased adrenaline secretion. Interestingly, [10]-shogaol is the only nonpungent compound among the gingerols and shogaols, suggesting its usefulness as a functional ingredient in food.

The odorants in the brew of cooked clam (Meretrix lusoria) were separated by adsorption into Tenax TA resin. An analysis by GC and GC−MS enabled 49 compounds to be unambiguously or tentatively identified. Among them, 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) (caramel-like), maltol (sweet), 2-acetyl-2-thiazoline (roasted), 2-acetylthiazole (popcorn-like), and 3-methylthiopropanal (boiled potato-like) were determined as the main potent odor compounds by an aroma extract dilution analysis. Since the concentrations of these compounds were increased with the longer cooking time, it was considered that the increase of these compounds was deeply related to the formation of the characteristic odor in the brew of cooked clam. Furthermore, by keeping the body of the clam at 4 °C for periods of 30 min, 2 h, 12 h, and 24 h before cooking, the formation of maltol and DMHF was increased significantly with increasing length of storage time, thus enhancing the flavor of the cooked clam. Keywords: Cooked clam; potent odorant; Tenax TA adsorption; DMHF; maltol; storage

Volatile compounds were isolated from cooked squid ( Todarodes paaficus STEENSTRUP) using a porous polymer resin with Tenax TA column chromatography. Aroma extract dilution analysis determined the following six compounds as the main potent odorants of cooked squid: 4~-dimethylthiazole (green), 2-acetyl-2-thiazoline (nutty), 2,5-dimethylpyrazine (popcorn-like), methional (potato, soy sauce), furaneol (caramel-like) and an unidentified compound (floral). Among them, based on the high concentration and odor characteristics, it is concluded that furaneol was the most important compound contributing to the sweet aroma of cooked squid.