Phytochemistry and Biological Activities of the Genus Knema (Myristicaceae)

Abstract

Introduction The genus Knema (Myristicaceae) is commonly found in tropical countries like Asia, Africa, and Australia. It comprises approximately 60 species in Southeast Asia but the evergreen forests in Thailand carries at least 12 species of this genus. 1 They are tropical trees with characteristic red resin in their bark, usually referred to by a word meaning 'blood' in their local names. Some Knema species are used for medical purposes where the barks and seeds are used in traditional medicine for treatment of diseases pertaining to skin or mouth and throat sores. The seeds of K. corlicosa are employed to prepare medicinal salves. 2-3 Previously, the genus Knema also contains a variety of natural compounds including acetophenone, substituted stilbene, lignan, flavonoid, alkyl/acyl resorcinol, and phenylalkylphenol derivatives. 4-8 Plants in this genus exhibited antibacterial, antinematodal, cytotoxicity, and acetylcholinesterase inhibitory activities. 9-12 Given that the genus is reported to be rich in health benefits, this review paper aims to phytochemically and pharmacologically investigate the different Knema species through previous literature that had reported its extraction, isolation, structural characterization, and description of biological activity of individual compounds. The SciFinder Scholar database was used to search for a substructure and was done via keyword searches in PubMed, Medline, and Scopus. The results indicated that to date, there have been citations of 12 species in this perspective. Each plant would get a discussion on its phytochemistry and pharmacognosy and listed in alphabetical order. Phytochemical Studies Since 1978, compounds 1-97 (Figure 1) have been isolated from the plants of the genus Knema. Their structures were shown below, and their names and corresponding plant sources were discussed below. A literature survey revealed that only twelve species of Knema genus have been investigated worldwide which are K.

New Acetophenone and Cardanol Derivatives From Knema pachycarpa

“…Knema is a genus of evergreen trees in the Myristicaceae family, comprising around 60 species distributed in tropical and subtropical regions of South East Asia. 1 Knema pachycarpa de Wilde is a native tree in Vietnam found in several central provinces. 2 Knema plants have been used in the traditional medicine for treatment of pimples, sores, and skin diseases.…”

Knecorticosanones C–H from the fruits of Knema globularia (Lam.) warb

“…Chemical investigation of the fruits of Knema globularia (Lam.) warb using a chromatographic method led to the isolation of eight polyketides (1)(2)(3)(4)(5)(6)(7)(8) and three lignans (9)(10)(11). Six new compounds, knecorticosanones C-H (1-6) were discovered, and in addition, ve known compounds including, knecorticosanones A and B (7 and 8), 10 8,8 0 -cis-cubebin (9), 16 (À)-a-cubebin (10) 17 and (À)-b-cubebin (11) 18 were also found (Fig.…”

“…The plant Knema genus (Myristicaceae) comprises over 60 species, and they are located in tropical Asia, Africa and Australia. 1 At least 12 species have been found distributed throughout Thailand. 2 Some Knema plants have been used to treat sore mouths and throats, pimples and skin diseases.…”

Phytopharmacological Review of Knema Attenuata (Hook F. And Thomson) Warb

“…This genus mostly consists of smallmedium trees has been used to treat sores, pimples, rheumatism, and cancer. The presence of a variety of natural compounds such as acetophenone, substituted stilbene, lignan, flavonoid, alkyl/acyl resorcinol, and phenylalkylphenol derivatives have been reported in the barks and seeds of genus Knema which exhibits antibacterial, antinematodal, anti-inflammatory, cytotoxicity, and acetylcholinesterase inhibitory activities [4]. A total of 8 species and 2 sub species were found in India out of which Knema attenuata (Hook.…”