A new compound, harzianum B (1), was isolated from the culture broth of a fungal strain, Hypocrea sp. F000527, together with a known trichothecene, harzianum A (2). Its structure was determined by spectroscopic analyses including HRFAB-MS and various (1)H NMR and (13)C NMR spectral data. Harzianum B (1) was characterised as (E,Z,E)-2', 4', 6'-octatriendioic acid esterified on the 4beta-hydroxyl group of trichodermol. Harzianums A (2) and B (1) showed cytotoxicity against several human cancer cell lines.

Chitinases help degradation of cell walls containing chitin and thus accelerates protoplast formation. It indirectly helps strain improvement and development of new strains which are economically viable for industrial use. Chitinases consist of endochitinase, exochitinase, b-N-acetylglucosaminidases and chitobiases. The endochitinases can be further characterized for better understanding of mechanism of the enzyme reaction. This review covers the recent advances in isolation and characterization of endochitinases and its components, gene encoding sequences and cloning.

Aims: To screen and clone a novel enzyme with specific activity for the resolution of (R)-b-acetylmercaptoisobutyrate (RAM) from (R,S)-b-acetylmercaptoisobutyrate [(R,S)-ester]. Methods and Results: A micro-organism that produces a novel esterase was isolated and identified as the bacterium Burkholderia cepacia by using the analysis of cellular fatty acids, Biolog automated microbial identification/characterization system, and 16S rRNA gene sequence analysis. A novel esterase gene was cloned from the chromosomal DNA of B. cepacia and was designated as cpoA. The cpoA encodes a polypeptide of 273 amino acids which shows a strong sequence homology with many bacterial nonhaeme chloroperoxidases. In addition, a typical serine-hydrolase motif, Gly-X-Ser-X-Gly, and the highly conserved catalytic triad, Ser95, Asp224, and His253, were identified in the deduced amino acid sequence of cpoA by multiple sequence alignment. Conclusion: The cpoA cloned from B. cepacia encodes a novel esterase which is highly related to the nonhaeme chloroperoxidases. Significance and Impact of the Study: This is the first report that describes the isolation and cloning of a serine esterase gene from B. cepacia, which is useful in the chiral resolution of (R,S)-ester. The cloned gene will allow additional research on the bifunctionality of the enzyme with esterase and chloroperoxidase activity at the structural and functional levels.

The optimal control algorithm to calculate the optimal feed rate pro®le of nutrient solution containing two limiting nutrients was proposed. Different from other conventional optimization methods, the proposed algorithm calculated the optimal control pro®les for different initial and feed conditions. The singular optimal control algorithm, dynamic programming, and nonsingular transformation algorithm were used for the optimization of simple problems of the 4th order and the performances were compared. With the proposed transformation algorithm, the ®nal MAb concentration increased and the CPU time decreased.For the different initial glucose and glutamine conditions, the optimal control pro®les were calculated with the proposed transformation algorithm. As the initial glutamine concentration increased, the ®nal MAb concentration also increased due to the cell viability increase. This was also applied to the different feed compositions. When the glutamine concentration was increased in the feed stream, the ®nal MAb concentration also increased.

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