## 3 Experimental Section
### Extraction and Isolation  
The strain KUFC 7898 was isolated from the alga _Amphiroa_ sp., which was collected from Samaesarn Island in the Gulf of Thailand, Chonburi Province, in September 2011. The alga was washed with 0.06% sodium hypochlorite solution for 1 min, followed by sterilized seawater three times. The alga was dried on sterile filter paper, cut into small pieces (5 \(\times\) 5 mm) and placed on a malt extract agar (MEA) medium containing 70% seawater and incubated at 28 \({}^{\circ}\)C for 5-7 days. The fungus was identified as _Neosartorya takakii_, by [PERSON] (Department of Plant Pathology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand), based on morphological characteristics such as colony growth rate and growth  
Figure 5: Ortep view of tryptoquivaline U (**3**). pattern on standard media, namely Czapek's agar (CZA), Czapek yeast autolyasate agar (CYA) and malt extract agar (MEA). Microscopic characteristics including size, shape, ornamentation of ascospores and _Aspergillus takakii_ anamorph were examined under light and scanning electron microscopes [14]. This identification was supported by sequence analysis of the \(\beta\)-tubulin, calmodulin and actin genes as described in the previous report [15]. _Neosartorya takakii_ was also confirmed by analysis sequence of the internal transcribed spacer (ITS) gene. Briefly, 2-15 mg of mycelia was ground in liquid nitrogen. DNA was extracted using the DNeasy(tm) Plant Mini Kit (QIAGEN, Hilden, Germany) according to the manufacturer's instructions. The entire nuclear ITS regions were amplified with the primers: ITS1F-5' [16] and ITS4-3' [17]. PCR reactions were conducted on Thermal Cycler and the amplification process consisted of initial denaturation at 95 \({}^{\circ}\)C for 5 min, 34 cycles at 95 \({}^{\circ}\)C for 1 min (denaturation), at 55 \({}^{\circ}\)C for 1 min (annealing) and at 72 \({}^{\circ}\)C for 1.5 min (extension), followed by final extension at 72 \({}^{\circ}\)C for 10 min. PCR products were cleaned using QIAquick PCR Purification Kit (QIAGEN, Hilden, Germany), then examined by Agarose gel electrophoresis (1% agarose with 1\(\times\) TBE buffer) and visualized under UV light after staining with ethidium bromide. DNA sequencing analyses were carried out by Macrogen Inc. (Seoul, South Korea). The sequences were compared using the NCBI nucleotide BLAST program ([[http://www.ncbi.nlm.nih.gov/BLAST](http://www.ncbi.nlm.nih.gov/BLAST)]([http://www.ncbi.nlm.nih.gov/BLAST](http://www.ncbi.nlm.nih.gov/BLAST))) for identification [18]. The pure cultures were deposited as KUFC 7898 at Kasetsart University Fungal Collection, Department of Plant Pathology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand, and also as MMERU 03 at Microbes Marine Environment Research Unit, Division of Environmental Science, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand. The fungus was cultured for one week at 28 \({}^{\circ}\)C in 10 Petri dishes (i.d. 90 mm) containing 25 mL of MEA with 70% seawater per dish. Fifty 1000 mL Erlenmeyer flasks, each containing rice (200 g), water (30 mL), and seawater (70 mL), were autoclaved, inoculated with five mycelia plugs of _N. takakii_ and incubated at 28 \({}^{\circ}\)C for 30 days, after which the moldy rice was macerated in ethyl acetate (15 L total) for 10 days and then filtered. The two layers were separated using a separating funnel and the ethyl acetate solution was concentrated under reduced pressure to yield 83.5 g of crude ethyl acetate extract which was dissolved in 500 mL of CHCl\({}_{3}\) and then washed with 5% NaHCO aqueous solution (2 \(\times\) 300 mL) and H\({}_{2}\)O (3 \(\times\) 300 mL).