Antifungal activity of plant extracts and oils against fungal pathogens of pepper (Piper nigrum L.), cinnamon (Cinnamomum zeylanicum Blume), and turmeric (Curcuma domestica Val.)
Year: 2005
Type: dissertation
Abstract: The antifungal and fungicidal effects of several water and ethanol extractions from plants and plant oils were studied in a series of in vitro and in vivo experiments against fungal pathogens of pepper (Piper nigrum L.), cinnamon (Cinnamomum zeylanicum Blume), and turmeric (Curcuma domestica Val.). Spore germination of several fungi was completely inhibited by cinnamon bark and leaf oils, clove bud and leaf oils, lemon grass oil, and garlic oil (at concentrations of 0.1 – 3%), and by water and water/ethanol (50%) extracts of galangal rhizome, galangal stem, cardamom leaf, cinnamon bark, and lesser galangal rhizome (at concentrations of 500 mg fresh weight/mL). The in vitro results revealed that ethanol extractions were more efficient than water extractions in inhibiting spore germination of several fungi. The highest inhibition of spore germination were provided by the oils of cinnamon (C. zeylanicum) and clove (Syzygium aromaticum [L.] Merr. et Perry). Cinnamon oil almost completely inhibited the germination of fungal spores. Extracts of galangal (Alpinia galanga [L.] Willd.) rhizomes and cardamom (Elettaria cardamomum Maton.) leaves (at concentrations of 500 mg fresh weight/mL) were the most effective in reducing spore germination of most of the fungi tested. However, the data showed that extracts and oils were less effective in in vivo experiments. With papaya (Carica papaya L.) seedlings, germination of Colletotrichum gloeosporioides was variable. The effects of extracts and oils were qualitative rather than quantitative. Application of extracts and oils reduced the symptoms of anthracnose caused by the fungus, but their effects against C. gloeosporioides were variable. It is suggested that this variability might be accounted for by the volatility of oil leading to a reduction of the concentration of active components on the leaves. Some extracts were phytotoxic at high concentrations and this had the unwanted effect of making infection easier for some fungi. SEM observations revealed damaged spores and hyphae of C.gloeosporioides when cinnamon bark oil and galangal rhizome extract were present. Finally, the data suggest that several plant extracts and oils may be a useful source of fungicidal preparations for agriculture use.
Author: Endah Yulia
Language: English
Subfield: Food Science
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W151277090