Screening and Identification of Endophytic Fungi in Scutellariae Radix Transformed Baicalin to Baicalein and Oroxylin A / 中国实验方剂学杂志

Objective: In order to explore natural active ingredients of Scutellariae Radix and alleviate the pressure of traditional medicinal resources,this research aimmed to screen endophytic fungus strains from Scutellariae Radix which could transform baicalin into some active ingredients.Method: Taking fresh plants of Scutellariae Radix as strain resource,endophytic fungus strains were isolated by potato dextrose agar (PDA) plate separation,Scutellariae Radix powder selective culture and HPLC detection.Result: An endophytic fungus strain R3 was isolated and it can transform baicalin to baicalein and oroxylin A simultaneously in potato dextrose broth (PDB) contained 0.1% baicalin and the conversion rate reached 61.09% in 5 d cultured at 28℃ and 150 r·min-1,molar ratio of baicalein and oroxylin A was 3:5.With the method of morphological analysis,microscopic identification and 18SrDNA sequence analysis,the bacterium was identified as Penicillium sp.R3. Conclusion: Penicillium sp.R3 can transform baicalin to baicalein and oroxylin A with certain research value and application value.

Mechanobiological model of bone remodeling based on stress state at cellular and molecular level / 医用生物力学

Objective To develop a mechanobiological model of bone remodeling based on stress state at cellular and molecular level. Methods Through analysis of bone remodeling process and mechanical stimulus from an engineering perspective, as well as absorption from the idea of mechanical strength design theory, the equivalent stress as the mechanical stimulus and the appropriate calculation formula of mechanical stimulus based on stress state were selected to propose a mechanobiological model of bone remodeling based on stress state at the cellular and molecular level. The model was then used to simulate bone remodeling of alveolar bone in orthodontics. Results The reduction of the vascular porosity and increase of bone mass appeared in tensile stress area, while vascular porosity increased and bone mass reduced in compression stress area, which was consistent with the features of alveolar bone. Conclusions The mechanobiological model of bone remodeling based on stress state at cellular and molecular level considered the effect of stress state on failure forms of bone tissues, embodied bone remodeling as a cellular automaton optimization process under mechanical stimulus, which would contribute to investigating effects of stress state on bone remodeling at the cellular and molecular level. The study is a supplement and improvement of bone remodeling theory and will provide theoretical guidance for treatment of orthodontics.

Mechanostat of bone remodelling under dynamic loads / 医用生物力学

Objective To discuss the mechanostat of bone remodeling under dynamic loads. Methods By analysis on mechanostat of bone remodeling and absorption from the idea of mechanical fatigue strength theory, the mechanostat of bone remodeling under dynamic loads was developed. Damage was selected as the mechanical stimulus under dynamic loads and the model of bone remodeling under dynamic loads was proposed. Physical exercise for prevention and treatment of osteoporosis was simulated to analyze the biomechanical phenomenon why the osteogenesis effect under dynamic loads seems better than that under static loads. Results The biomechanical phenomenon as mentioned above was reasonably explained. An increase of 10%-30% in physical exercise could cause an increase of 3.13%-8.61% in bone mineral density. Conclusions The mechanostat of bone remodeling under dynamic loads will provide theoretical guidance for using mechanical vibration to treat or prevent diseases related to bone metabolism, which is the supplement and improvement for mechanostat of bone remodeling.

Studies on coumarins from fruit of Cnidium monnieri and their cytotoxic activities / 中国中药杂志

This study is to study is to investigate the coumarins from Fruit of Cnidium monnieri and their cytotoxic activities. The constituents were separated by column chromatography, and their structures were elucidated by spectroscopic data analyses. The isolated compounds were evaluated for their cytoxic activities by MTT method. Eleven compounds were isolated and identified as osthole (1), bergaptan (2), xanthotoxol (3), xanthotoxin (4), imperatorin (5), isopimpinellin (6), osthenol (7), psoralen (8), 5,7-dimethoxycoumarin (9), oxypeucedaninhydrate (10), and swietenocoumarin F (11). Compounds 7, 9-11 were isolated from the Cnidium genus for the first time. Compounds 1,5,10 and 11 showed significant cytotoxic activities against L1210 cell lines at a concentration of 1 x 10(-5) mol x L(-1) with inhibitory rates of were 70.13, 63.10, 55.77, and 75.08% respectively.

Studies on flavonoids from stems of Nelumbo nucifera Gaertn and their cytotoxic activities / 中国中药杂志

This research is to investigate study the flavonoids from stems of Nelumbo nucifera and the cytotoxic activities of iso- lated compounds. The constituents were separated by column chromatography,and their structures were elucidated by spectroscopic data analyses. The isolated compounds were evaluated for cytoxic activities by MTT method. Twelve compounds were isolated and identified as rhamnazin-3-O-beta-D-glucopyranoside (1), luteolin-3', 4'-dimethylether-7-O-beta-D-glucoside (2), kaempferol-3-O-beta-D-xylopyranosyl-(1-->2)-O-beta-D-glucopyranoside (3), quercetin-3,3'-di-O-beta-D-glucopyranoside (4), 1, 8-dihydroxy-3,7-dimethoxyxanthone (5), isorhamnetin-3-O-beta-D-glucopyranoside(6) , kaempferol(7), isorhamnetin (8), quercetin(9), astragalin(10), hyperoside (11) and 1-hy- droxy-3,7,8-trimethoxyxanthone(12). All compounds were isolated from stems of this plant for the first time, and compounds 1-5 were firstly isolated from the family nelumbonaceae. Compounds 24 and 6 showed significant cytotoxic activities against BEL-7402 carcinoma cell lines at a concentration of 1 x 10(-5) mol x L(-1) with the inhibitory rate of 67.36%, 53.25%, 57.78%, 60.13% and 52.11%, respectively.