Combined spectroscopic and molecular docking approach to probing binding interactions between lovastatin and calf thymus DNA.

The binding interaction of lovastatin with calf thymus DNA (ct-DNA) was studied using UV/Vis absorption spectroscopy, fluorescence emission spectroscopy, circular dichroism (CD), viscosity measurement and molecular docking methods. The experimental results showed that there was an obvious binding interaction of lovastatin with ct-DNA and the binding constant (Kb ) was 5.60 × 10(3) M(-1) at 298 K. In the binding process of lovastatin with ct-DNA, the enthalpy change (ΔH(0)) and entropy change (ΔS(0)) were -24.9 kJ/mol and -12.0 J/mol/K, respectively, indicating that the main binding interaction forces were van der Waal's force and hydrogen bonding. The molecular docking results suggested that lovastatin preferred to bind on the minor groove of different B-DNA fragments and the conformation change of lovastatin in the lovastatin-DNA complex was obviously observed, implying that the flexibility of lovastatin molecule plays an important role in the formation of the stable lovastatin-ct-DNA complex.

Analyses of microbial consortia in the starter of Fen Liquor.

AIMS: This study aimed to determine the microbial diversity in the starter of Fen Liquor. METHODS AND RESULTS: The plate method was used to enumerate the micro-organisms; meanwhile, the 16S rDNA of bacteria and the internal transcribed spacer of fungi were used to determine microbial diversity. Several genera were accordingly identified. Among the bacteria, Lactobacillales and Actinomycetales were detected only on the surface of the starter, whereas Bacillales was dominant within the starter. Among the fungi, Saccharomycopsis and Issatchenkia were the main genera in surface and interior starter, respectively; in addition, Thermomyces was found in interior starter, while other species of fungi were detected on the surface. CONCLUSIONS: The culture-dependent and polymerase chain reaction-based methods revealed the significant microbial diversity in different locations in the starter of Fen Liquor. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first to identify the bacterial and fungal communities associated with the starter of Fen Liquor using both traditional and molecular methods; it is also the first to compare the microbial diversity on the surface of starter with that in the interior. The results enrich our knowledge on liquor-related micro-organisms, and can be used to promote the development of the traditional fermentation technology.