Primary study on the components and main physico-chemical as well as biological properties of the oil of Alpinia galanga (L.) Wild in Phu Tho-Vietnam

Abstract

The oil of Alpinia galanga (L.) Willd in Phu Tho was obtained by steam distillation and dried with Na 2 SO 4. By Gas chromatography-mass spectrometry (GC-MS) method, 29 components in the oil were predicted by comparing their retention times and molecular weights with the standards'. In particular, there were 10 hydrocarbons such as monoterpenes: 29.15%, sesquiterpenes: 21.06%, and 19 oxygenated components like aldehydes (7.29%), alcohols (32.43%), ketones (1.09%), and esters (7.57%). Physico-chemical properties, antioxidant activities as well as antimicrobial activities of the oils were also analyzed. The density (at 20°C), acid index and ester index of the oil were 0.812 g/ml; 0.653 mg KOH/g and 0.728 mg KOH/g, respectively. The antioxidant activity was determined by using 1,1diphenyl-2-picrylhydrazol (DPPH) radical percentage inhibition and it was 47.15±0.34%. Antimicrobial activity against Salmonella typhi, Bacillus cereus, Staphylococcus aureus and Escherichia coli of the oil was identified by agar diffusion method.

An overview of the chemical composition and biological activities of essential oils fromAlpiniagenus (Zingiberaceae)

“… 61 The rhizome essential oil of galangal from Nawinna, Sri Lanka mainly contained zerumbone, p -cymene and camphene, 62 whereas the samples from Indonesia were characterized by the predominance of β-bisabolene and trans -caryophyllene. 63 In addition, the whole plant oil of galangal from Phu Tho, Vietnam mainly contained limonene, borneol and geranyllinelol as the major constituents, 64 while the rhizome oil from Ha Noi, Vietnam was found to be rich in 1,8-cineole, neral and geranial. 65…”

“…59 The essential oils extracted from A. galanga grown in Phu Tho, Vietnam had an inhibitory effect on Salmonella typhimurium , Bacillus cereus , Staphylococcus aureus and Escherichia coli . 64 In addition, the essential oil from the leaf of A. malaccensis was reported to have antimicrobial activity against oral bacteria and fungi, including Staphylococcus aureus , Pseudomonas aeruginosa , Candida albicans and Aspergillus niger with MIC values of 1.95, 7.81, 5.5, 6.7 μL mL −1 , respectively. 68 The rhizome essential oil of A. galanga from Vietnam showed antimicrobial activity against Staphylococcus aureus , Bacillus subtilis , Streptococcus faecalis , Escherichia coli , Proteus vulgaris , Salmonella enteritidis and Saccharomyces cerevisiae with MIC values ranging from 2.5 to 20 μL mL −1 .…”

“…The antioxidant activity of the essential oil of A. galanga collected from Phu Tho, Vietnam was determined using 1,1-diphenyl-2-picrylhydrazol (DPPH) with a percentage inhibition of 47.15%. 64 The essential oils obtained from the leaves of A. malaccensis from Odisha, India showed strong radical-scavenging activities, as evaluated using the DPPH and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays, with IC 50 values of 18.26 μg mL −1 and 20 μg mL −1 , respectively. 68 Meanwhile, the antioxidant effect of the essential oil from the leaf of A. malaccensis var.…”