Laccase from Trametes polyzona WR710-1 was produced under solid-state fermentation using the peel from the Tangerine orange (Citrus reticulata Blanco) as substrate, and purified to homogeneity. This laccase was found to be a monomeric protein with a molecular mass of about 71 kDa estimated by SDS-PAGE. The optimum pH was 2.0 for ABTS, 4.0 for L-DOPA, guaiacol, and catechol, and 5.0 for 2,6-DMP. The K(m) value of the enzyme for the substrate ABTS was 0.15 mM, its corresponding V(max) value was 1.84 mM min(-1), and the k(cat)/K(m) value was about 3960 s(-1)  mM(-1). The enzyme activity was stable between pH 6.0 and 8.0, at temperatures of up to 40 °C. The laccase was inhibited by more than 50% in the presence of 20 mM NaCl, by 95% at 5 mM of Fe(2+), and it was completely inhibited by 0.1 mM NaN(3). The N-terminal amino acid sequence of this laccase is AVTPVADLQISNAGISPDTF, which is highly similar to those of laccases from other white-rot basidiomycetes.

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Purified laccase from Trametes polyzona WR710-1 was used as biocatalyst for bisphenol A biodegradation and decolorization of synthetic dyes. Degradation of bisphenol A by laccase with or without redox mediator, 1-hydroxybenzotriazole (HBT) was studied. The quantitative analysis by HPLC showed that bisphenol A rapidly oxidized by laccase with HBT. Bisphenol A was completely removed within 3 h and 4-isopropenylphenol was found as the oxidative degradation product from bisphenol A when identified by GC-MS. All synthetic dyes used in this experiment, Bromophenol Blue, Remazol Brilliant Blue R, Methyl Orange, Relative Black 5, Congo Red, and Acridine Orange were decolorized by Trametes laccase and the percentage of decolorization increased when 2 mM HBT was added in the reaction mixture. This is the first report showing that laccase from T. polyzona is an affective enzyme having high potential for environmental detoxification, bisphenol A degradation and synthetic dye decolorization.

A novel leaf fall disease of rubber trees (Hevea brasiliensis) has been recently noted in Thailand. The fungal pathogens of this disease were identified based on both morphological and molecular characteristics as Neopestalotiopsis cubana and N. formicarum. Portions of internal transcribed spacer (ITS) region and the large subunit (LSU), translation elongation factor 1‐α (TEF1‐α) and β‐tubulin (TUB) genes were PCR amplified with the primer pairs ITS1/ITS4, LR0R/LR5, EF1‐728F/EF2 and T1/Bt2b, respectively. Sequencing of the PCR products and a phylogenetic tree based on the combined ITS, TEF1‐α and TUB confirmed these pathogens as N. cubana and N. formicarum. Pathogenicity test results showed that the pathogens cause leaf spot and leaf fall similar to that observed in natural infections. This is the first report on the novel leaf fall disease of rubber trees in Thailand, with the results demonstrating that it is associated with N. cubana and N. formicarum.

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In July 2016, wet rot was observed on leaves of Brassica chinensis in a private greenhouse in Hatyai city, Songkhla province, Thailand. The fungal pathogen infected young and expanded leaves. The fungus was identified by morphological characterization and molecular analysis as Choanephora cucurbitarum. Pathogenicity test revealed that C. cucurbitarum could infect B. chinensis.

Lettuce (Lactuca sativa) is an annual vegetable that is widely cultivated in hydroponic systems in Thailand. In 2016, a leaf spot disease was commonly found on hydroponically-grown lettuce plants in glasshouses in Songkhla province, southern Thailand. The morphology of the fungus that was consistently isolated from the leaf spots was identical to that described for Corynespora cassiicola. The identity of the fungus was confirmed by sequencing the ITS and LSU gene regions. Koch's postulates were satisfied, proving that C. cassiicola was the causal agent of the recent outbreaks of leaf spot in hydroponically-grown lettuce in Thailand. This paper is the first report of the disease in this country.