Abstract:
Engelhardia is a genus of seven species of trees in the family Juglandaceae, native to southeast Asia. In China, the genus is mainly distributed in Guangdong, Hainan, Guangxi, Guizhou, Yunnan and other places. The genus name is commonly misspelled “Engelhardtia”, a “correction” made by the original author Carl Ludwig Blume in 1829 was used until today, as it was thus entered in the Index Kewensis; the original spelling is Engelhardia. According to the literature, the Genus of: Engelhardia include 26 Species: Engelhardtia aceriflora, E. apoensis, E. aurifolia, E. danumensis, E. hainanensis, E. kinabaluensis, E. lepidota, E. mendalomensis, E. mersingensis, E. mollis, E. nicaraguensis, E. nudiflora, E. boreomunnea, E. palembanica, E. parvifolia, E. permicrophylla, E. philippinensis, E. polystachya, E. pterococca, E. rigida, E. selanica, E. serrata, E. spicata, E. subsimplicifolia, E. villosa, and E. zambalensis.
Ethnopharmacologically, The herb has detoxification effects on spleen and stomach stagnation, chest and abdomen bloating, cold fever, diarrhea, hernia abdominal pain and so on. Its root, bark, leaves and flowers can be used as medicine, the medicinal bark is slightly bitter, pungent and calm. The leaf medicine is slightly bitter and cool. Folk said the leaves of the herbal medicine called sweet tea since ancient times as a heat, detoxification for weight loss health care.
Modern pharmacologically, the studies have shown that the herb has main pharmacological activities for hypoglycemic action, hypolipidemic effects, anticoagulant, anti-platelet aggregation, anti-thrombosis, anti-inflammatory, anti-cancer, enhancing immunity, inhibition of cardiovascular and cerebrovascular diseases and so on.
From a large number of documents, many researchers found that the chemical constituents, pharmacology and toxicology of Fructus genus were studied. It mainly contains flavonoids, polyphenols and saponins.
The review article entitled “Chemical Constituents and Pharmacological Effects of Genus Engelhardia” (CHM 2018, 10(1):xx-xx) provides a wealth of informatics on chemical constituents and pharmacological researches of genus Engelhardia Leschen. ex Blume. The constituents of this genus were introduced and classified according to their structures. Based on the large amount of constituents, this genus plants exhibited various biological activities such as antioxidant, protective effects on ischemia/reperfusion injury, anticancer, anti-inflammatory, immunosuppression activities, antidiabetic and antitubercular activities and so on. Authers compared with some common species, current research of genus Engelhardia is not quite enough to elucidate the relationship between chemical constituents, pharmacological data and traditional medical usage. Most studies focused on E. roxburghiana possibly due to its broader distribution and wider usage than other species in the past. Later, parts of the genus plants were further studied, and more pharmacological activities were found. As national medicine and health tea, the usage parts of Engelhardia plants is not extensive, which cause not much attention. With various biological activities, genus Engelhardia might have considerable potential value for the development of new drugs. For example, dihydroflavonoids show immunosuppressive activity due to its lower cytotoxicity. E. roxburghiana is rich in these constituents, which means it will take good therapeutic effects on autoimmune diseases such as rheumatoid arthritis and systemic lupus erythematosus. In this paper, authors suggested that genus Engelhardia has a good development prospects. Researchers look forward that the genus Engelhardia plants not only E. roxburghiana, but also other species can attract more attention.
A total of over 100 compounds have been isolated from the genus Engelhardia, in which phenolic derivatives are dominant compounds including flavonoids, triterpenes, diarylheptanoids, aromatic acids, esters, and naphthalenones. From a development perspective, there are many issues in discovery and development that need to be made in how to combine modern pharmacological research with valuable new drugs for discovery. Additionally, biological activity of most natural chemical composition is not strong, and pharmacokinetic characteristic is not prominent (such as low bioavailability), which could be modified for improving the biological activity of the potential.