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, 3-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 IC 50 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.

This research focuses on isolation and identification of polyunsaturated fatty acid (PUFA) producing fungi from natural sources of Thailand, followed by experimental designs for carbon and nitrogen utilizations of the potential strains. The results show that 8 and 16 isolates of lower fungi from freshwater and wet-fallen leaves, respectively, could produce PUFAs. Among these isolates, the NR06 that was isolated from wet-fallen leaves at Tad Ta Phu waterfall, Nakhon Ratchasrima province. They showed the highest level productions of both biomass (15.49±0.24 gl -1 ) and total fatty acids (16.44±0.30%). The major essential fatty acid composition was found to be arachidonic acid (ARA; C20:4n6) (32.24±0.35%). The minors were linoleic acid (C18:2n6) (8.26±0.59%) and γ-linoleic acid (GLA; C18:3n6) (5.48±0.08%). Besides the morphological characterization, taxonomic identification by the 636 bp-ITS region sequencing and phylogenetic analysis were performed. It was demonstrated that the fungal isolate NR06 was classified in the closest species of Mortierella elongata with 99% similarity (GenBank accession no. KF181625). Statistically based experimental designs (Design Expert 7.1 software) were applied to the optimization of biomass and fatty acid production in the NR06 culture. Using the glucose as a carbon source, there was a significant effect on both biomass and ARA production (p-values < 0.0001), whereas using yeast extract as a nitrogen source affected only ARA production (p-value = 0.02). It was suggested that the NR06 isolate could be further optimized for an improvement as a potential ARA producing strain.