No abstract

This study was to isolate and identify the antifungal compounds in the ethyl acetate soluble fraction of the methanol extractives of Taiwania (Taiwania cryptomerioides Hayata) heartwood and to examine their antifungal activity. Five compounds were obtained by open column chromatography and HPLC and based upon the results from Mass, 1 H-NMR, and 13 C-NMR analyses. Their structures were identified, namely ferruginol, helioxanthin, savinin, taiwanin C, and hinokiol. According to the results of antifungal test, the order of antifungal index of these compounds for Coriolus versicolor (L. ex Fr.) Quel. was ferruginol > taiwanin C > savinin > hinokiol. For Laetiporus sulphureus (B. ex Fr.) Bond. it was taiwanin C > savinin > ferruginol > hinokiol.

The leaf and fruit essential oils of Litsea cubeba, extracted by hydrodistillation, were assessed for anticancer activities. A total of 53 and 50 compounds were identified, respectively from the leaf and fruit oils, and their yields were 13.9 ± 0.09% and 4.0 ± 0.03%, v/w, of the oven-dried materials, respectively. The main compound in the leaf oil was 1,8-cineol, and in the fruit oil, citral. The fruit oil, but not that of the leaf, exhibited cytotoxic activity against human lung, liver and oral cancer cells.

The hydrodistillated leaf essential oil of Machilus pseudolongifolia was analyzed to determine its composition and yield. Seventy compounds were identified, the main components being β-eudesmol (26.8%), α-cadinol (20.8%), viridiflorene (8.9%), α-caryophyllene (5.3%), globulol (4.6%) and β-caryophyllene (4.2%). Oxygenated sesquiterpenes (60.1%) and sesquiterpene hydrocarbons (31.4%) were the predominant groups of compounds. The leaf oil exhibited excellent antimicrobial and anti-wood-decay fungal activities.

This study identifies a new fungal strain, Lentinus sp., that can produce extracellular forms of laccases with an activity of approximately 58 300 U/L. A purified laccase (designated lcc3) was identified by LC-ESI MS/MS as an N-linkage glycosylated protein. The isolated lcc3 cDNA is composed of 1563 bp encoding for a polypeptide of 521 amino acid residues with 4 putative Cu binding regions. Kinetic analyses revealed that the specific activity, k(cat), K(m), and k(cat)/K(m) of lcc3 at pH 2.5 and 70 °C with 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) used as a substrate was 2047 U mg(-1), 2017 s(-1), 8.4 μM, and 240 s(-1) μM(-1), respectively. Lcc3 is stable at pH 6.0-10.0 and has a midpoint temperature (T(m)) of 77.1 °C. We observed 97% decolorization efficiency on Acid Blue 80, 88% on RBBR, and 61% on Acid Red 37 by lcc3. Structural modeling analysis showed that five, four, and three hydrogen bonds can be formed between Acid Blue 80 and Arg(178), Arg(182), or Asn(358); between RBBR and His(132), Ser(134), or Asp(482); and between Acid Red 37 and Arg(178), respectively. Notably, Lentinus lcc3 efficiently reversed the toxicity of anthraquinone and azo dyes on rice seed germination and decolorized industrial textile effluent, suggesting the enzyme may be valuable for bioremediation.