Metal ion of metal-organic frameworks facilitating immobilized chitinase performance.

Metal-organic framework (MOF) structures containing different metal ions and 1,3,5-trimesic acid (BTC) were fabricated, as the carriers to immobilize chitinase (Chi) for improving the performance of Chi, for the first time. It was found that the immobilization of Chi on Ca-BTC, Ba-BTC, and Ni-BTC increased its activity. Notably, the specific activity of Chi@Ca-BTC was enhanced by 2.

A novel microbial-derived family 19 endochitinase with exochitinase activity and its immobilization.

A novel chitinase gene of 888 bp from Streptomyces bacillaris was cloned and expressed in Escherichia coli BL21. The purified recombinant enzyme (SbChiAJ103) was identified as the first microbial-derived family 19 endochitinase that showed exochitinase activity. SbChiAJ103 exhibited the substrate preference for N-acetylchitooligosaccharides with even degrees of polymerization and the capability to specifically hydrolyze colloidal chitin into (GlcNAc).

α-Carotene: a valuable carotenoid in biological and medical research.

α-Carotene, one of the C carotenes, is a natural lipid-soluble terpene. The chemical structure of α-carotene is based on the unsaturated polyene chain skeleton, with an ε-ring and a β-ring on each side of the skeleton. α-Carotene is widely found in dietary fruits and vegetables, and the concentration depends on the plant species.

[Reasons that seedless fruits of Siraitia grosvenorii become small].

Objective: To study the reasons that the seedless fruits of Siraitia grosvenorii developed to smaller ones.

Methods: The differences of fruit expanding, gene expressing and cell development were investigated between the triploid and diploid fruits from two strains F050 and F049.

Results: The results showed the expanding of triploid fruits was stopped about 20 days after artificial pollination, 10 days earlier than the diploid fruits.