Antifungal Activity fromAlpinia galangaand the Competition for Incorporation of Unsaturated Fatty Acids in Cell Growth

Abstract

An antimicrobial diterpene was isolated from Alpinia galanga in the screening for potentiators of phytochemical antibiotic action. The structure was elucidated by spectral data and identified as (E)-8 beta, 17-epoxylabd-12-ene-15, 16-dial (1). Diterpene 1 synergistically enhanced the antifungal activity of quercetin and chalcone against Candida albicans. Antifungal activity of 1 was reversed by unsaturated fatty acids. Protoplasts of C. albicans were lysed by 1. These results suggest that antifungal activity of 1 is due to a change of membrane permeability arising from membrane lipid alternation.

Inhibition of 10% Alpinia galanga and Alpinia purpurata rhizome extract on Candida albicans growth

“…16 C. albicans have a thick structure as composed of chitin, mannan, and glucan which causes stiffness and low permeability so that when moistened with alcohol, the cell walls cannot be penetrated and the violet gentian dye is still remained in the cell and will make cells looks purple. 14 The 10% Alpinia galanga rhizome extract and 10% Alpinia purpurata rhizome extract were capable of inhibiting the growth of C. albicans with the average of the inhibition response about 7.33 mm for Alpinia Galanga rhizome extract and 6 mm for Alpinia purpurata rhizome [8][9][10] The inhibition response of Alpinia galanga rhizome extract toward the growth of C. albicans can happen because the extract contains both diterpene compounds, such as acetoxychavicol acetate, and flavonoid compounds, such as kaempferol, kaempferide, galangin, alpinin and essential oils which are antifungal compounds. 6,7 The diterpene compounds work by altering the lipid membrane of C. albicans, so the changes of their membrane permeability occur.…”

“…6,7 The diterpene compounds work by altering the lipid membrane of C. albicans, so the changes of their membrane permeability occur. 9 Meanwhile, flavonoids work by inhibiting the synthesis of nucleic acids of fungi and destabilizing the cell membranes due to the change of the nature of the fungal cell membrane that may cause the exchange of fluid in the cell. On the other hand, the inhibition response of Alpinia purpurata rhizome is caused by the fact that it contains saponins, tannins, flavonoids, essential oils and diterpen compounds.…”

“…Further studies also show that diterpene works by altering the lipid membrane of C. albicans then resulting in the changes of the permeability of its membrane. 9 A test conducted on Alpinia galanga rhizome extract with concentration of 10% even shows that there were antifungal activities against C. albicans in vaginalis candidiasis. 8 On the other hand, red ginger (Alpinia purpurata) contains flavonoids, saponins and tannins.…”

A Review on Phytochemical and Pharmacological Potential of Alpinia galanga

“…20 An antimicrobial diterpene was isolated from the rhizome of Alpinia galanga. The structure was elucidated by spectral data and identified as (E) -8 beta, 17-epoxylabd-12-ene-15, 16-dial 21 ).…”

“…The identified structure of the compound was (E)-8β, 17-epoxylabd-12-ene-15, 16-dial. 21 The activity of endophyti-cactinomycetes obtained from root of Alpinia galanga against phytopathogenic fungi was tested against Candida albicans, and phytopathogenic fungi, Colletotrichummasae and Fusariumoxysporum. The strain, Strepto myces aureofaciensCMUAc130 was the most effective in antifungal activity amongst those investigated.…”