ScienceAsia 45(2019): 127-137 |doi:
Effects of drying and extraction methods on phenolic
compounds and in vitro assays of Eclipta prostrata
Linn leaf extracts
Woranan Nakbanpotea, Munjit Ruttanakorna, Kannika Sukadeetada, Niramol Sakkayawongb,
ABSTRACT: Eclipta prostrata Linn leaves have a potential to be an alternative source of commercial herbal extracts.
The effects of different drying methods (oven-drying at 60 ?C, freeze drying, and microwave drying) on polyphenol
and antioxidant activities of E. prostrata were reported. The extractions with absolute ethanol and freeze-drying
preserved higher levels of total phenolic content and total flavonoid content than those of the oven and microwavedrying methods. Correlation analysis indicated that phenolic and flavonoid compounds were the major antioxidants
in E. prostrata extracts. Drying methods were a critical factor following the order of freeze-dried, microwave dried,
oven-dried leaf extracts, for which the extraction methods seemed to have no correlation with the properties of the
extracts. The E. prostrata ethanolic extracts contained flavonoids (luteolin, luteolin glucoside, luteolin sulphate,
wedelolactone, dimethylwedelolactone, dimethylwedelolactone sulphate, 30-hydroxybiochanin A), phenolic acids
(gallic acid, protocatechuic acid, caffeoylquinic acid, dicaffeoylquinic acid), phenolic aldehyde (protocatechualdehyde),
and triterpenoids (eclalbasaponin). High performance thin layer chromatography of the crude extracts from the freezedried leaves and soxhlet extraction gave the main wedelolactone, chlorophyll, and some non-phenolic compounds. The
IC50 values of the crude extracts for anti-proliferation of HaCaT cells indicated less efficiency for psoriasis treatment.
However, an appropriate extraction of E. prostrata leaves to obtain high luteolin and wedelolactone contents has been
suggested for a further development of local and systemic treatments for other inflammatory skin diseases.
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||Department of Biology, Faculty of Science, Mahasarakham University, Maha Sarakham 44150 Thailand
||Department of Biotechnology, Faculty of Science and Technology, Thammasat University,
Pathum Thani 12120 Thailand
* Corresponding author, E-mail: email@example.com
Received 31 Aug 2018, Accepted 30 Apr 2019