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Wen-Teish Chang

Publications and source records attributed to Wen-Teish Chang.

5 recordsLinked to original sources

Antifungal activity and enhancement of plant growth by Bacillus cereus grown on shellfish chitin wastes.

Bacillus cereus QQ308 produced antifungal hydrolytic enzymes, comprising chitinase, chitosanase and protease, when grown in a medium containing shrimp and crab shell powder (SCSP) produced from marine waste. The growth of the plant-pathogenic fungi Fusarium oxysporum, Fusarium solani, and Pythium ultimum were considerably affected by the presence of the QQ308 culture supernatant. The supernatant inhibited spore germination and germ tube elongation of F. oxysporum, F. solani, and P. ultimum. The increase in the growth time of the fungal culture was associated with a gradual decrease in inhibition. Besides antifungal activity, QQ308 enhanced growth of Chinese cabbage. These characteristics were unique among known strains of B. cereus. To our knowledge, this is the first report on the antifungal and Chinese cabbage growth enhancing compounds produced by B. cereus.

Antifungal Agents↗

Polysaccharides of Ganoderma lucidum alter cell immunophenotypic expression and enhance CD56+ NK-cell cytotoxicity in cord blood.

In our previous study, a fucose-containing glycoprotein fraction (F3), isolated from the water-soluble extracts of Ganoderma lucidum, was shown to stimulate mice spleen cell proliferation and cytokine expression. We now further investigate the effect of F3 on the immunophenotypic expression in mononuclear cells (MNCs). When human umbilical cord blood (hUCB) MNCs were treated with F3 (10-100 microg/mL) for 7days, the population of CD14+CD26+ monocyte/macrophage, CD83+CD1a+ dendritic cells, and CD16+CD56+ NK-cells were 2.9, 2.3, and 1.5 times higher than those of the untreated controls (p<0.05). B-cell population has no significant change. T cell growth was, however, slightly inhibited and CD3 marker expression decreased approximately 20% in the presence of higher concentrations of F3 (100 microg/mL). We also found that F3 is not harmful to human cells in vitro, and after F3 treatment, NK-cell-mediated cytotoxicity was significantly enhanced by 31.7% (p<0.01) at effector/target cell ratio (E/T) 20:1, but was not altered at E/T 5:1.

CD56 Antigen↗

Cell phenotype analysis using a cell fluid-based microchip with high sensitivity and accurate quantitation.

We have assessed a cell fluid chip-based fluorescent cytometric assay that runs on bioanalyzer for fast characterization of small population cell phenotypes characterization. The assay determines the expression of specific cell surface markers on various cell samples. Six samples can be analyzed on each chip in one automated process. Results were in good agreement with conventional flow cytometry in quantitation. Importantly, this procedure used less than 200 cells per sample and produced results consistent with that using 10(5) cells by the conventional staining procedure. The method was also used for screening potential ingredients in herbs. Purpose of this study was to analyze the change of cell subtypes of UCB mononuclear cells in vitro reactivity in herbs. We found that by treatment of the water-soluble extract (F3) of Ganoderma lucidum, the presence of CD56(+) marker (natural killer cells) significantly increased from 1.1 to 3.2% (P<0.05 and P) in UCB mononuclear cells. The results indicated that F3 quantitatively influenced NK cells activities. We suggest this screening method may be useful for a fast phenotypes characterization after extract stimulation utilizing only a small population of cells.

Cells, Cultured↗

An antifungal chitinase produced by Bacillus cereus with shrimp and crab shell powder as a carbon source.

The production of inexpensive chitinolytic enzymes is an element in the utilization of shellfish processing wastes. In this study, shrimp and crab shell powder prepared by treating shrimp and crab processing wastes with boiling and crushing was used as a substrate for the isolation of an antifungal chitinase-producing microorganism. Bacillus cereus YQ 308, a strain isolated from the soil samples, excreted one chitinase when cultured in a medium containing 2% (wt/vol) shrimp and crab shell powder as major carbon source. The chitinase, purified by sequential chromatography, had an Mr of 48 kDa and pI of 5.2. The purified chitinase (2 mg/ml) inhibited the hyphal extension of the fungi Fusarium oxysporum and Pythium ultimum.

Animals↗

Purification and characterization of an antimicrobial chitinase extracellularly produced by Monascus purpureus CCRC31499 in a shrimp and crab shell powder medium.

Monascus purpureus CCRC31499 produced an antimicrobial chitinase when it was grown in a medium containing shrimp and crab shell powder (SCSP) of marine wastes. An extracellular antimicrobial chitinase was purified from the culture supernatant to homology. The chitinase had a molecular weight of approximately 81,000 and a pI of 5.4. The optimal pH, optimum temperature, and pH stability of the chitinase were pH 7, 40 degrees C, and pH 6-8, respectively. The activity of the chitinase was activated by Fe(2+) and strongly inhibited by Hg(2+). The unique characteristics of the purified chitinase include high molecular weight, nearly neutral optimum pH, protease activity, and antimicrobial activity with bacteria and fungal phytopathogens. This is also the first report of isolation of a chitinase from a Monascus species.

Animals↗