Aim To establish a method for determination of Ginkgo biloba L, its extractand preparations with HPLC fingerprints, so as to control the quality of the preparations. MethodsHPLC-DAD method was used to determine the co...Aim To establish a method for determination of Ginkgo biloba L, its extractand preparations with HPLC fingerprints, so as to control the quality of the preparations. MethodsHPLC-DAD method was used to determine the constituents in preparations. Diamonsil? C_(18) (200mm X 4.6 mm, 5 μm) was used as analytical column, and acetonitrile/KH_2PO_4 was used as mobilephase with gradient elu-tion. The column temperature was at 24 ℃. The HPLC profile of chemicalconstituents of control sample and preparations were analyzed using similarity software. Results Thefingerprints of different preparations from different companies were slightly different because ofthe different preparing procedures. Mean while, the fingerprints of different batches of the samepreparation from the same company were similar to each other and the technology of each preparationwas stable. Conclusion This method is accurate, reproducible , simple, and can be used as ananalytical method for the routine quality control of Ginkgo biloba preparations.展开更多
Besides control of the fungal plant pathogens, another interesting aspect observed when plants are treated with Trichoderma harzianum include effects such as complete and even stand of plants, improved seed germinatio...Besides control of the fungal plant pathogens, another interesting aspect observed when plants are treated with Trichoderma harzianum include effects such as complete and even stand of plants, improved seed germination, increases in plant height and overall enhanced plant growth. No research has yet been conducted to elucidate the mechanism by which these effects occur. Improved seed germination, in particular, suggest that Trichoderma harzianum produces a metabolite that may mimic the plant growth hormone gibberellic acid. The metabolite gliotoxin, produced by Trichoderma harzianum appear to be structurally most similar to gibberellic acid. In this study, common pharmacophore generation and molecular ligand docking simulations were used to evaluate the molecular similarity between gibberellic acid, specifically GA3, and gliotoxin. For the common pharmacophore evaluation, the structure of various gibberellic acids were used to construct a pharmacophore space to which gliotoxin was aligned, and during the molecular docking simulations the gibberellic acid receptor, GID1, served as ligand target for GA3 and gliotoxin. During the common pharmacophore evaluation, gliotoxin was successfully aligned to the common pharmacophore model constructed from various gibberellic acids. Furthermore, molecular docking simulations of gliotoxin and GA3 into the gibberellic acid receptor （GIDI） yielded docking scores of-10.78 kcal/mol for the GA3 molecule from Corina and a docking score of-10.17 kcal/mol for glioto^in. The docking scores suggest that gliotoxin may be able to competitively occupy the receptor space for gibberellic acid, and as such elicit the similar physiological responses observed in literature.展开更多
The successful face recognition based on local binary pattern(LBP)relies on the effective extraction of LBP features and the inferring of similarity between the extracted features.In this paper,we focus on the latter ...The successful face recognition based on local binary pattern(LBP)relies on the effective extraction of LBP features and the inferring of similarity between the extracted features.In this paper,we focus on the latter and propose two novel similarity measures for the local matching methods and the holistic matching methods respectively.One is Earth Mover's Distance with Hamming and Lp ground distance(EMD-HammingLp),which is a cross-bin dissimilarity measure for LBP histograms.The other is IMage Hamming Distance(IMHD),which is a dissimilarity measure for the whole LBP images.Experiments on FERET database show that the proposed two similarity measures outperform the state-of-the-art Chi-square similarity measure for extraction of LBP features.展开更多
文摘Aim To establish a method for determination of Ginkgo biloba L, its extractand preparations with HPLC fingerprints, so as to control the quality of the preparations. MethodsHPLC-DAD method was used to determine the constituents in preparations. Diamonsil? C_(18) (200mm X 4.6 mm, 5 μm) was used as analytical column, and acetonitrile/KH_2PO_4 was used as mobilephase with gradient elu-tion. The column temperature was at 24 ℃. The HPLC profile of chemicalconstituents of control sample and preparations were analyzed using similarity software. Results Thefingerprints of different preparations from different companies were slightly different because ofthe different preparing procedures. Mean while, the fingerprints of different batches of the samepreparation from the same company were similar to each other and the technology of each preparationwas stable. Conclusion This method is accurate, reproducible , simple, and can be used as ananalytical method for the routine quality control of Ginkgo biloba preparations.
文摘Besides control of the fungal plant pathogens, another interesting aspect observed when plants are treated with Trichoderma harzianum include effects such as complete and even stand of plants, improved seed germination, increases in plant height and overall enhanced plant growth. No research has yet been conducted to elucidate the mechanism by which these effects occur. Improved seed germination, in particular, suggest that Trichoderma harzianum produces a metabolite that may mimic the plant growth hormone gibberellic acid. The metabolite gliotoxin, produced by Trichoderma harzianum appear to be structurally most similar to gibberellic acid. In this study, common pharmacophore generation and molecular ligand docking simulations were used to evaluate the molecular similarity between gibberellic acid, specifically GA3, and gliotoxin. For the common pharmacophore evaluation, the structure of various gibberellic acids were used to construct a pharmacophore space to which gliotoxin was aligned, and during the molecular docking simulations the gibberellic acid receptor, GID1, served as ligand target for GA3 and gliotoxin. During the common pharmacophore evaluation, gliotoxin was successfully aligned to the common pharmacophore model constructed from various gibberellic acids. Furthermore, molecular docking simulations of gliotoxin and GA3 into the gibberellic acid receptor （GIDI） yielded docking scores of-10.78 kcal/mol for the GA3 molecule from Corina and a docking score of-10.17 kcal/mol for glioto^in. The docking scores suggest that gliotoxin may be able to competitively occupy the receptor space for gibberellic acid, and as such elicit the similar physiological responses observed in literature.
文摘The successful face recognition based on local binary pattern(LBP)relies on the effective extraction of LBP features and the inferring of similarity between the extracted features.In this paper,we focus on the latter and propose two novel similarity measures for the local matching methods and the holistic matching methods respectively.One is Earth Mover's Distance with Hamming and Lp ground distance(EMD-HammingLp),which is a cross-bin dissimilarity measure for LBP histograms.The other is IMage Hamming Distance(IMHD),which is a dissimilarity measure for the whole LBP images.Experiments on FERET database show that the proposed two similarity measures outperform the state-of-the-art Chi-square similarity measure for extraction of LBP features.
