Lentinic acid

Lenthionine (53) is one of flavoring substances in Lentinus edodes (Berk.) Sing (67CPB988). It was proposed that 53 is produced by polymerization of the parent dithiirane (54), which was formed from lentinic acid (55) by enzymatic and then nonenzymatic processes (76TL3129 77MI1). 

Mushrooms have been investigated with especial reference to shiitake, Lentinus edodes, the flavorful fungus widely used in Chinese and Japanese dishes. While the umami taste is attributed to guanylic acid, lentinic acid 14 (Scheme 6) is converted to lenthionine, 1,2,3,5,6-pentathiacycloheptane 15, a compound with the characteristic shiitake flavor. This complex reaction requires a C-S lyase enzyme.30 Other important flavor compounds are 1,2,4,6-tetrathiacycloheptane 16 (Scheme 6) and 1,2,3,4,5,6-hexathiacycloheptane (not shown). 

Lenthionine has the characteristic shiitake flavor. It is formed from the precursor, lentinic acid 14 by complex reactions involving a C-S lyase enzyme.30 Cyclic polysulfides occur in other Basidiomycete mushrooms (Genus Micromp-hale and Colly bid), in some red alga, and in seeds of Parkia speciosa. The latter contain lenthionine and 1,2,4-trithiolane (1,2,4-trithiacyclopentane) 17 as well as compounds with 4, 5, or 6 sulfur atoms.31 These seeds are valued in Indonesia for a unique, onion-like odor. Djenkolic acid and dichrostachinic acid S -[(2-carboxy-2-hydroxyethylsulfonyl)-methyl]cysteine are converted by a C-S lyase enzyme to cyclic polysulfides djenkolic acid yields 1,2,4-trithiolane and 1,2,4,6-tetrathiepane the latter is also formed from dichrostachinic acid.32... 

Figure 1. Proposed pathway of formation of S-compounds in Shiitake mushroom. (1) lentinic acid (2) des-glutamyl lentinic acid (3) a thiosulfinate, SE-3 (4) methylene disulfide (5) lenthionine (7) 1,2,3,4,5,6-hexathiepane.

Lentinic Acid (2-y-L-Glutamylainino-4,6,8,10,10-pentaoxo-4,6,840-tetrathiaundecanoic Acid)... 

Lentinic acid -h L-amino acid y-glutamylamino acid +... 

The enzyme is also present in Micromphale performs and Collybia hariolorum, both of which are sources of lentinic acid 100), and a y-glutamyl transpeptidase is present in Marasmius species containing y-glutamylmarasmine (72). 

Lentinic acid (34) in Lentinus edodes is degraded first by the action of a transpeptidase to desglutamyllentinic acid (35), as described in Section VII. 3. Desglutamyllentinic acid is then cleaved by action of a... 

Epilentinic acid, a diastereoisomer of lentinic acid (Table 4, compare Section V. 7) has been isolated free from lentinic acid from Micromphale cauvetii, M. foetidum and Collybia impudica 397). 

Reactivity of Lentinus y-glutamyltransferase with lentinic acid as the... 

Enzyme-catalysed evolution of lenthionine from lentinic acid. Agric. Biol. 

Yasumoto, K., K. Iwami, H. Mizusawa, and H. Mitsuda Preparation of des-glutamyllentinic acid, a new sulfur-containing amino acid, from lentinic acid and its... 

Its threshold values are 0.27-0.53 ppm (in water) or 12.5-25 ppm (in edible oil) It is derived biosynthetically from an S-alkyl cysteine sulfoxide, lentinic acid. Truffles, edible potato-shaped fungi, contain approx. 50ng/g 5a-androst-16-ene-3 a-ol, which has a musky odor that contributes to the typical aroma (cf. 3.8.2.2.1). 

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