The seed of Myristica fragrans Houtt
(nutmeg) is one of the important spices that have been extensively
used in the culinary, food, beverage, and also in medicinal products
industry. Previous phytochemical studies on nutmeg were mainly focused
on lignans and neolignans. However, the other constituents have been
poorly studied. In this study, 11 new monoterpene-conjugated phenolic
derivatives, named myrifratins A–K (1–11), and five known compounds were isolated from nutmeg. The
novel neolignan–diarylnonanoid–monoterpene conjugates
(1 and 2) were first isolated in nature.
Compounds 3–7 were rarely monoterpene–diarylnonanoid-conjugated
derivatives, and 8–11 were the first
examples of monoterpene–neolignan conjugates. Compounds 4–6, 12, and 13 showed potent autophagy inhibitory activities in a concentration-dependent
manner. Our findings showed an uncommon class of monoterpene-conjugated
phenolic derivatives in nature and reported their autophagy inhibition
activities for the first time, which may give a new insight into the
benefits or safety of nutmeg in foods.