Density functional theory （DFT） was used to calculate a set of molecular descri ptors （properties） for 14 fluoroquinolones with anti-B.fragilis activity. Principal component analysis （PCA） and hierarchical clust...Density functional theory （DFT） was used to calculate a set of molecular descri ptors （properties） for 14 fluoroquinolones with anti-B.fragilis activity. Principal component analysis （PCA） and hierarchical cluster analysis （HCA） were employed in order to reduce dimensionality and investigate which subset of variables should be more effective for classifying fluoroquinolones according to their an-B.fragilis activity degree. The PCA shows that the variables of ELUMO, AEHL, μ, Q2, Q3, Q5, Q6, QB, LogP, MR and MP are responsible for the separation between compounds with higher and lower anti-B.fragilis activities. The HCA results are similar to those obtained with PCA. By using the chemometric results, 4 synthetic compounds were analyzed through PCA and HCA, and 2 of them are proposed as active molecules against B.fragilis, which is consistent with the results of clinic experiments. The methodologies of PCA and HCA provide a reliable rule for classifying new fluoroquinolones with anti-B.fragilis activity.展开更多
[Objectives]To compare the effects of molecular distillation on the flavor and antitumor activity of Ganoderma lucidum spore oil.[Methods]G.lucidum spore oil was separated and purified by molecular distillation techno...[Objectives]To compare the effects of molecular distillation on the flavor and antitumor activity of Ganoderma lucidum spore oil.[Methods]G.lucidum spore oil was separated and purified by molecular distillation technology,and the volatile components of different components of molecular distillation were analyzed by gas chromatography-ion mobility spectrometry(GC-IMS)technology.Human liver carcinoma cells(HepG2),human breast cancer cells(MCF-7),and human cervical cancer cells(Hela)were selected as the tumor cell lines to be tested,and the cell viability was detected by the MTT assay.[Results]Molecular distillation effectively reduced small molecular substances produced by oil oxidation in G.lucidum spore oil,such as heptanal,octanal,linalool,hexanal,E-2-octanal,3-ethylpyridine,etc.Among the heavy components,the content of esters was relatively high,mainly including ethyl levulinate,ethyl crotonate,and amyl butyrate.The MTT cytotoxicity test indicated that G.lucidum spore oil and its molecular distillation components had certain inhibitory effects on the growth of three tumor cells,and G.lucidum spore oil crude oil had the most significant antitumor activity.G.lucidum spore oil crude oil,heavy component,and light component had the most significant antitumor activity on HepG2 cells,followed by MCF-7 cells,and the weakest antitumor activity on Hela cells.The quality of G.lucidum spore oil became higher after molecular distillation,and the rancid smell was reduced,and molecular distillation had little effect on the antitumor activity of G.lucidum spores.[Conclusions]Molecular distillation technology can be applied to the refining of G.lucidum spore oil to improve product quality.展开更多
Popular descriptive multivariate statistical method currently employed is the principal component analyses （PCA） method. PCA is used to develop linear combinations that successively maximize the total variance of a ...Popular descriptive multivariate statistical method currently employed is the principal component analyses （PCA） method. PCA is used to develop linear combinations that successively maximize the total variance of a sample where there is no known group structure. This study aimed at demonstrating the performance evaluation of pilot activated sludge treatment system by inoculating a strain of Pseudomonas capable of degrading malathion which was isolated by enrichment technique. An intensive analytical program was followed for evaluating the efficiency of biosimulator by maintaining the dissolved oxygen （DO） concentration at 4.0 mg/L. Analyses by high performance liquid chromatographic technique revealed that 90% of malathion removal was achieved within 29 h of treatment whereas COD got reduced considerably during the treatment process and mean removal efficiency was found to be 78%. The mean pH values increased gradually during the treatment process ranging from 7.36-8.54. Similarly the mean ammonia-nitrogen （NH3-N） values were found to be fluctuating between 19.425-28.488 mg/L, mean nitrite-nitrogen （NO3-N） ranging between 1.301- 2.940 mg/L and mean nitrate-nitrogen （NO3-N） ranging between 0.0071-0.0711 mg/L. The study revealed that inoculation of bacterial culture under laboratory conditions could be used in bioremediation of environmental pollution caused by xenobiotics. The PCA analyses showed that pH, COD, organic load and total malathion concentration were highly correlated and emerged as the variables controlling the first component, whereas dissolved oxygen, NO3-N and NH3-N governed the second component. The third component repeated the trend exhibited by the first two components.展开更多
Cordyceps militaris,belongs to Clavicipitaceae family,was investigated for its chemical compounds,and six compounds were isolated and purified by silica gel column chromatography,Sephadex LH-20 and recrystallization,a...Cordyceps militaris,belongs to Clavicipitaceae family,was investigated for its chemical compounds,and six compounds were isolated and purified by silica gel column chromatography,Sephadex LH-20 and recrystallization,and their structures were elucidated by spectral techniques and physicochemical properties as ergosterol(1),adenosine(2),cordycepin(3),ergosterol peroxide(4),tetracosanoic acid 2,3-dihydroxypropylester(5),mannitol(6).Procoagulant activity was screened by assaying the activated partial thromboplastin time(APTT),prothrombin time(PT),thrombin time(TT)and fibrinogen(FIB)in vitro.The results indicated that ergosterol,adenosine,cordycepin,ergosterol peroxide and mannitol showed strong procoagulant activity.展开更多
In this study, four samples of Tunisian propolis were analyzed for their volatile compounds. Static Headspace technique coupled with gas chromatography-mass spectrometry (GC/MS) was used for the volatile profile chara...In this study, four samples of Tunisian propolis were analyzed for their volatile compounds. Static Headspace technique coupled with gas chromatography-mass spectrometry (GC/MS) was used for the volatile profile characterization. Statistical investigation of the samples was made applying hierarchical clustering method, K-Means cluster and principal component analysis. Results showed that 47, 36, 30 and 24 different compounds were identified, respectively, in the samples from Zouarine, Zelligua, Bizerte and Beni Khalled. Propolis volatiles were dominated by monoterpene hydrocarbons. α-pinene was the major compound representing 81.14%, 82.67% and 90.74%, respectively, of the total propolis volatiles collected from Zelligua, Beni Khalled and Zouarine and only 45.22% of the sample from Bizerte which had a very different composition. The in vitro antifungal activity of the volatiles from all samples against Candida albicans was also assayed and reported.展开更多
Density functional theory （DFT） was used to calculate a set of molecular descriptors （properties） for 14 TIBO derivatives with anti-HIV activity. Principal component analysis （PCA） and hierarchical cluster analy...Density functional theory （DFT） was used to calculate a set of molecular descriptors （properties） for 14 TIBO derivatives with anti-HIV activity. Principal component analysis （PCA） and hierarchical cluster analysis （HCA） were employed in order to reduce dimensionality and investigate which subset of variables should be more effective for classifying TIBO derivatives according to their degree of anti-HIV activity. The PCA showed that the EHOMO, μ, LogP, QA, QB and MR variables are responsible for the separation between compounds with higher and lower anti-HIV activity. The HCA results are similar to those obtained with PCA. By using the chemometric results, four synthetic compounds were analyzed through PCA and HCA and three of them are proposed as active molecules against HIV, which is consistent with the results of clinic experiments. The methodologies of PCA and HCA provide a reliable rule for classifying new TIBO derivatives with anti-HIV activity. The model obtained showed not only statistical significance but also predictive ability.展开更多
Structure-activity relationship techniques were employed to classify fluoroquinolones against S.pneumoniae. Density functional theory （DFT） was used to calculate a set of molecular descriptors （properties） for eig...Structure-activity relationship techniques were employed to classify fluoroquinolones against S.pneumoniae. Density functional theory （DFT） was used to calculate a set of molecular descriptors （properties） for eighteen fluoroquinolones. The descriptors were further analyzed using the principal component analysis （PCA）, hierarchical cluster analysis （HCA） and K-nearest neighbor （KNN） chemometeric method. The PCA and HCA methods are quite efficient to classify the eighteen compounds into two groups （active and inactive） according to their degrees of anti- S.pneumoniae activity. The classified result is consistent with the clinic experimental result. The PCA shows that the variables Q3 （net charge on atom 3）, QA （net charge on ring A）, QB （net charge on ring B）, VOL （molecular volume） and A （surface area） are found to be responsible for the separation between compounds with higher and lower anti-S.pneumoniae.展开更多
Active Shape Model （ASM） is a powerful statistical tool to extract the facial features of a face image under frontal view. It mainly relies on Principle Component Analysis （PCA） to statistically model the variabil...Active Shape Model （ASM） is a powerful statistical tool to extract the facial features of a face image under frontal view. It mainly relies on Principle Component Analysis （PCA） to statistically model the variability in the training set of example shapes. Independent Component Analysis （ICA） has been proven to be more efficient to extract face features than PCA. In this paper, we combine the PCA and ICA by the consecutive strategy to form a novel ASM. Firstly, an initial model, which shows the global shape variability in the training set, is generated by the PCA-based ASM. And then, the final shape model, which contains more local characters, is established by the ICA-based ASM. Experimental results verify that the accuracy of facial feature extraction is statistically significantly improved by applying the ICA modes after the PCA modes.展开更多
基金The project was supported by the National Natural Science Foundation of China (No. 10574096)
文摘Density functional theory （DFT） was used to calculate a set of molecular descri ptors （properties） for 14 fluoroquinolones with anti-B.fragilis activity. Principal component analysis （PCA） and hierarchical cluster analysis （HCA） were employed in order to reduce dimensionality and investigate which subset of variables should be more effective for classifying fluoroquinolones according to their an-B.fragilis activity degree. The PCA shows that the variables of ELUMO, AEHL, μ, Q2, Q3, Q5, Q6, QB, LogP, MR and MP are responsible for the separation between compounds with higher and lower anti-B.fragilis activities. The HCA results are similar to those obtained with PCA. By using the chemometric results, 4 synthetic compounds were analyzed through PCA and HCA, and 2 of them are proposed as active molecules against B.fragilis, which is consistent with the results of clinic experiments. The methodologies of PCA and HCA provide a reliable rule for classifying new fluoroquinolones with anti-B.fragilis activity.
基金Supported by Taishan Industrial Leading Talent Project(Efficient Ecological Agriculture Innovation)(LJNY202105)。
文摘[Objectives]To compare the effects of molecular distillation on the flavor and antitumor activity of Ganoderma lucidum spore oil.[Methods]G.lucidum spore oil was separated and purified by molecular distillation technology,and the volatile components of different components of molecular distillation were analyzed by gas chromatography-ion mobility spectrometry(GC-IMS)technology.Human liver carcinoma cells(HepG2),human breast cancer cells(MCF-7),and human cervical cancer cells(Hela)were selected as the tumor cell lines to be tested,and the cell viability was detected by the MTT assay.[Results]Molecular distillation effectively reduced small molecular substances produced by oil oxidation in G.lucidum spore oil,such as heptanal,octanal,linalool,hexanal,E-2-octanal,3-ethylpyridine,etc.Among the heavy components,the content of esters was relatively high,mainly including ethyl levulinate,ethyl crotonate,and amyl butyrate.The MTT cytotoxicity test indicated that G.lucidum spore oil and its molecular distillation components had certain inhibitory effects on the growth of three tumor cells,and G.lucidum spore oil crude oil had the most significant antitumor activity.G.lucidum spore oil crude oil,heavy component,and light component had the most significant antitumor activity on HepG2 cells,followed by MCF-7 cells,and the weakest antitumor activity on Hela cells.The quality of G.lucidum spore oil became higher after molecular distillation,and the rancid smell was reduced,and molecular distillation had little effect on the antitumor activity of G.lucidum spores.[Conclusions]Molecular distillation technology can be applied to the refining of G.lucidum spore oil to improve product quality.
文摘Popular descriptive multivariate statistical method currently employed is the principal component analyses （PCA） method. PCA is used to develop linear combinations that successively maximize the total variance of a sample where there is no known group structure. This study aimed at demonstrating the performance evaluation of pilot activated sludge treatment system by inoculating a strain of Pseudomonas capable of degrading malathion which was isolated by enrichment technique. An intensive analytical program was followed for evaluating the efficiency of biosimulator by maintaining the dissolved oxygen （DO） concentration at 4.0 mg/L. Analyses by high performance liquid chromatographic technique revealed that 90% of malathion removal was achieved within 29 h of treatment whereas COD got reduced considerably during the treatment process and mean removal efficiency was found to be 78%. The mean pH values increased gradually during the treatment process ranging from 7.36-8.54. Similarly the mean ammonia-nitrogen （NH3-N） values were found to be fluctuating between 19.425-28.488 mg/L, mean nitrite-nitrogen （NO3-N） ranging between 1.301- 2.940 mg/L and mean nitrate-nitrogen （NO3-N） ranging between 0.0071-0.0711 mg/L. The study revealed that inoculation of bacterial culture under laboratory conditions could be used in bioremediation of environmental pollution caused by xenobiotics. The PCA analyses showed that pH, COD, organic load and total malathion concentration were highly correlated and emerged as the variables controlling the first component, whereas dissolved oxygen, NO3-N and NH3-N governed the second component. The third component repeated the trend exhibited by the first two components.
基金National Key R&D Program of China(2018YFD040020)Industry&University Research Project in Henan Province(182107000033).
文摘Cordyceps militaris,belongs to Clavicipitaceae family,was investigated for its chemical compounds,and six compounds were isolated and purified by silica gel column chromatography,Sephadex LH-20 and recrystallization,and their structures were elucidated by spectral techniques and physicochemical properties as ergosterol(1),adenosine(2),cordycepin(3),ergosterol peroxide(4),tetracosanoic acid 2,3-dihydroxypropylester(5),mannitol(6).Procoagulant activity was screened by assaying the activated partial thromboplastin time(APTT),prothrombin time(PT),thrombin time(TT)and fibrinogen(FIB)in vitro.The results indicated that ergosterol,adenosine,cordycepin,ergosterol peroxide and mannitol showed strong procoagulant activity.
文摘In this study, four samples of Tunisian propolis were analyzed for their volatile compounds. Static Headspace technique coupled with gas chromatography-mass spectrometry (GC/MS) was used for the volatile profile characterization. Statistical investigation of the samples was made applying hierarchical clustering method, K-Means cluster and principal component analysis. Results showed that 47, 36, 30 and 24 different compounds were identified, respectively, in the samples from Zouarine, Zelligua, Bizerte and Beni Khalled. Propolis volatiles were dominated by monoterpene hydrocarbons. α-pinene was the major compound representing 81.14%, 82.67% and 90.74%, respectively, of the total propolis volatiles collected from Zelligua, Beni Khalled and Zouarine and only 45.22% of the sample from Bizerte which had a very different composition. The in vitro antifungal activity of the volatiles from all samples against Candida albicans was also assayed and reported.
基金The project was supported by the National Natural Science Foundation of China (No. 10574096)
文摘Density functional theory （DFT） was used to calculate a set of molecular descriptors （properties） for 14 TIBO derivatives with anti-HIV activity. Principal component analysis （PCA） and hierarchical cluster analysis （HCA） were employed in order to reduce dimensionality and investigate which subset of variables should be more effective for classifying TIBO derivatives according to their degree of anti-HIV activity. The PCA showed that the EHOMO, μ, LogP, QA, QB and MR variables are responsible for the separation between compounds with higher and lower anti-HIV activity. The HCA results are similar to those obtained with PCA. By using the chemometric results, four synthetic compounds were analyzed through PCA and HCA and three of them are proposed as active molecules against HIV, which is consistent with the results of clinic experiments. The methodologies of PCA and HCA provide a reliable rule for classifying new TIBO derivatives with anti-HIV activity. The model obtained showed not only statistical significance but also predictive ability.
文摘Structure-activity relationship techniques were employed to classify fluoroquinolones against S.pneumoniae. Density functional theory （DFT） was used to calculate a set of molecular descriptors （properties） for eighteen fluoroquinolones. The descriptors were further analyzed using the principal component analysis （PCA）, hierarchical cluster analysis （HCA） and K-nearest neighbor （KNN） chemometeric method. The PCA and HCA methods are quite efficient to classify the eighteen compounds into two groups （active and inactive） according to their degrees of anti- S.pneumoniae activity. The classified result is consistent with the clinic experimental result. The PCA shows that the variables Q3 （net charge on atom 3）, QA （net charge on ring A）, QB （net charge on ring B）, VOL （molecular volume） and A （surface area） are found to be responsible for the separation between compounds with higher and lower anti-S.pneumoniae.
文摘Active Shape Model （ASM） is a powerful statistical tool to extract the facial features of a face image under frontal view. It mainly relies on Principle Component Analysis （PCA） to statistically model the variability in the training set of example shapes. Independent Component Analysis （ICA） has been proven to be more efficient to extract face features than PCA. In this paper, we combine the PCA and ICA by the consecutive strategy to form a novel ASM. Firstly, an initial model, which shows the global shape variability in the training set, is generated by the PCA-based ASM. And then, the final shape model, which contains more local characters, is established by the ICA-based ASM. Experimental results verify that the accuracy of facial feature extraction is statistically significantly improved by applying the ICA modes after the PCA modes.
