Variation of contents of six oligosaccharides in the roots of Morinda officinalis how in different growing periods / 中国药学杂志

OBJECTIVE: To determine the contents of six oligosaccharides, i. e. glucose, fructose, sucrose, 1-kestose, nystose, 1-fructofuranosylnystose, in the roots of Morinda officinalis in different growing periods by HPAEC-PAD method. METHODS: The separation was performed on Hamilton RCX-10 column(4.1 mm × 250 mm, 7 μm) with gradient elution using mobile phase composed of 100 mmol · L-1 NaOH(A) and mixture of 100 mmol · L-1 NaOH and 500 mmol · L-1 NaOAc (B) at a flow rate of 0.8 mL · min-1 and the temperature was kept at 35℃. The injection volumn was 25 μX. The gradient elution program was as follows: 0-5 min, 1%B; 5-15 min, 1%-9% B; 15-20 min, 9%-12% B; 20-25 min, 12%-16% B; 25-40 min, 16%-50% B; 40-43 min, 50% B; 43-46 min, 50%-1% B. RESULTS: With the increase of growing periods, the content of monosaccharide progressively reduced while that of sucrose gradually increased. The contents of oligosaccharides with polymerization degree of 3 or greater, including 1-kestose, nystose, and 1-fructofuranosylnystose, slowly increased during 1-5 years, then slowed down. CONCLUSION: The contents of six oligosaccharides in the roots of Morinda officinalis vary greatly in different growing periods, indicating that the biosynthesis of oligosacchride in Morinda officinalis is related to growing periods. The result provides a reference for determination of appropriate collection time.

Enzymatic hydrolysis of sugarcane bagasse pretreated with acid or alkali

The aim of this study was to evaluate the performance of enzymatic hydrolysis of acid or alkali pretreated sugarcane bagasse for the production of fermentable sugars. The first step consisted of selection of commercial enzymes presenting the highest cellulolytic activities. After selection of four enzymes: HPL, CL, P1 and P4, their performances were tested in the bagasse pretreated with acid and alkali. The sugar content of the hydrolysates was analyzed by anion exchange liquid chromatography. Data showed that the joint action of 0.5 percent acid pretreatment, 121ºC, 30 minutes and enzyme CL provides the best results, 67.25 g of hexose and 148.13g of pentose per kg of dry bagasse.