Objective:To evaluate the in-vitro antioxidant and antimicrobial activity of cvcloart-23- ene-3β,25-diol(called as B2) isolated from stem bark of Pongamia pinnata.Methods:In vitro antioxidant activity of B2 was deter...Objective:To evaluate the in-vitro antioxidant and antimicrobial activity of cvcloart-23- ene-3β,25-diol(called as B2) isolated from stem bark of Pongamia pinnata.Methods:In vitro antioxidant activity of B2 was determined by methods for determination of Dl’PH radical scavenging,reducing power,superoxide anion radical scavenging,hydroxyl radical scavenging, hydrogen peroxide scavenging,metal chelating and nitric oxide radical scavenging at the doses of 20.40.60.80 and 100μg/mL,respectively.3 -tocopherol with same concentration was used as a standard antioxidant.In vitro antimicrobial activity of B2 was determined by cup plate method in different concentration range of 10-100μg/mL.Results:The results indicated that dose dependent%reduction against DPPH radical,reducing power,superoxide anion radical scavenging,hydroxyl radical scavenging,metal chelating,hydrogen peroxide scavenging and nitric oxide radical scavenging by B2 andβ-tocopherol.Conclusions:It is concluded that cycloart 23-ene-3β,25 diol(B2) showed dose dependent antioxidant activity.B2 showed more DPPH radical scavenging,reducing power,superoxide scavenging,hydroxyl radical scavenging, metal chelating scavenging,hydrogen peroxide radical scavenging and nitric oxide radical scavenging activity thanβ-tocopherol and in case of antimicrobial activity B2 exhibited broad-spectrum activ ity against bacteria and strong activity against yeast type of fungi.展开更多
Aims: The representativeness of the mandatory bacterial strains specified in European standards for in vitro assay of the bactericidal activity of antiseptics was evaluated by testing the activity of an antiseptic com...Aims: The representativeness of the mandatory bacterial strains specified in European standards for in vitro assay of the bactericidal activity of antiseptics was evaluated by testing the activity of an antiseptic combining chlorhexidine digluconate 0.2% and benzalkonium chloride 0.5% against 21 additional bacterial strains, and the positive interaction between these two biocidal agents was assessed. Methods and Results: The bactericidal activity of the antiseptic solution used pure or diluted was assessed according to the European standards EN 1040 and EN 13727. The contact time was 1 min at 20°C. Interfering substances used in the EN 13727 assay were bovine serum albumin and sheep erythrocytes, simulating “dirty” conditions, and hard water. A reduction of colony-forming units by ≥5 log10 was deemed to meet the requirements to conclude bactericidal activity. Under “basic” conditions, the bactericidal activity of the antiseptic was observed against all four mandatory strains specified in the standards as well as against nearly all the additional strains tested, including most of those with acquired antibiotic-resistance. The positive interaction between the two biocidal agents was also confirmed. Under “dirty” conditions, the bactericidal activity of the antiseptic solution was maintained against all the mandatory strains and was reduced against only four of the additional strains tested. Conclusions: With regard to the antiseptic tested and under the experimental conditions described, bactericidal activity evidenced against the mandatory strains appeared to be representative of that manifested against a wide range of the main pathogenic bacteria. Reduced bacterial activity against some of the additional strains tested (e.g. Enterobacteriaceae) was observed under “dirty” conditions. Significance and Impact of the Study: EN 13727 with some experimental adjustments represents an additional appropriate standard that needs to be considered for mucocutaneous antiseptic assessment. However, it may be worth including other specific bacterial strains to those specified in the standard, when evaluating antiseptics intended for use in certain clinical situations.展开更多
A new compound, 3,6,20（S）-trihydroxy- 12,23-epoxydammar-24-ene,6,20-di-O-β-D-glucopyranoside （1）, was isolated from the leaves of Panax ginseng C.A. Meyer, whose structural elucidation was carried out by means of...A new compound, 3,6,20（S）-trihydroxy- 12,23-epoxydammar-24-ene,6,20-di-O-β-D-glucopyranoside （1）, was isolated from the leaves of Panax ginseng C.A. Meyer, whose structural elucidation was carried out by means of spectral analysis （including IR, HR- FAB-MS and NMR）. This compound showed the moderate cytotoxic activities against U937 and HeLa cells by using the MTT method.展开更多
Phytochemical investigation of the purified fractions of the active dichloromethane extract of Hysterionica pinifolia (Poir.) Baker led to the identification of five compounds. New acetylenic alcohol (E)-undec-3-en-5,...Phytochemical investigation of the purified fractions of the active dichloromethane extract of Hysterionica pinifolia (Poir.) Baker led to the identification of five compounds. New acetylenic alcohol (E)-undec-3-en-5,7-diyne-1-ol (1) and three other compounds (3), (4), and (5) were reported for the first time in this species. Furthermore, forty-six components from the volatile fraction of H. pinifolia were identified. These compounds were elucidated using 1D and 2D NMR spectroscopy as well as MS-ESI and GC-FID-MS experiments. The dichloromethane extract, its fractions, and the methanolic extract were tested for insecticidal activity against Tribolium castaneum under laboratory conditions. The dichloromethane extract and the fraction F2 were found to be active, showing high larval mortality. The dichloromethane extract was also active against T. castaneum adults. The results have shown that H. pinifolia could be considered, in a near future, as a potential source for the development of a botanical insecticide for pest control.展开更多
Nicotine [3-(1-methyl-2-pyrrolidinyl)-pyridine], a major alkaloid in tobacco products, has proven to be a potential genotoxic compound. Some polyphenolic compounds can suppress the DNA adduction, and hence act as the ...Nicotine [3-(1-methyl-2-pyrrolidinyl)-pyridine], a major alkaloid in tobacco products, has proven to be a potential genotoxic compound. Some polyphenolic compounds can suppress the DNA adduction, and hence act as the potential inhibitors of carcinogenesis. In this study, the inhibitory effects of three polyphenolic compounds, curcumin (diferuloylmethane), resveratrol (trans-3, 5, 4-trihydroxystilbene) and tea polyphenols, on the nicotine-DNA adduction have been investigated in vitro using radiolabelled nicotine and liquid scintillation counting (LSC) technique. Also, the inhibition mechanism of these chemopreventive agents in regard to the activity of the biotransformation enzymes, including cytochrome P450 (CYP450), cytochrome b5 (CYb5) and glutathione S-transferase (GST), has been studied. The results demonstrated that these three polyphenols induced marked dose-dependent decrease in nicotine-DNA adducts as compared with the controls. The elimination rate of adducts reached above 46% at the highest dose for all the three agents with 51.6% for resveratrol. Correspondingly, three polyphenols all suppressed CYP450 and CYb5, whereas curcumin and resveratrol induced GST. We may arrive at a point that the three polyphenols are beneficial to prevent the nicotine adduct formation, and thus may be used to block the potential carcinogenesis induced by nicotine.展开更多
The novel fungicidal agents, （E）-5-[1-（2-oxo-l-oxaspiro[4,5]dec/non-3-en-3-yl）ethylidene]-2-aminoimidazolin- 4-one derivatives, were designed and synthesized in moderate to excellent yields in four steps using a-h...The novel fungicidal agents, （E）-5-[1-（2-oxo-l-oxaspiro[4,5]dec/non-3-en-3-yl）ethylidene]-2-aminoimidazolin- 4-one derivatives, were designed and synthesized in moderate to excellent yields in four steps using a-hydroxyketone and diketene as raw materials and characterized by HR-ESI-MS, 1H NMR and X-ray diffraction. The preliminary bioassay showed that some of these compounds, such as 5e, 6a, 6e, and 7h exhibit 87.8%, 91.3%, 89.9% and 87.8% inhibition rates against Sclerotinia scleotiorum, 3b, 3c, 4c and 7h exhibit 96.4%, 92.5%, 90.3% and 76.9% inhibition rates against Phytophthora capsici at the concentration of 50 μg/mL, respectively. These compounds exhibited significant fungicidal activities against S. scleotiorum and P. capsici with EC50 values of 2.56 --11.60 μg/mL, and compounds 6e and 7h exhibited weak inhibition against the spore germination of S. scleoti- orum, while the spore germination ofP. capsici was strongly inhibited by compound 7h solution. Scanning electron microscopy （SEM） and transmission electron microscopy （TEM） observation indicated that compound 7h had a significant impact on the structure and function of the hyphal cell wall ofP. capsici mycelium.展开更多
文摘Objective:To evaluate the in-vitro antioxidant and antimicrobial activity of cvcloart-23- ene-3β,25-diol(called as B2) isolated from stem bark of Pongamia pinnata.Methods:In vitro antioxidant activity of B2 was determined by methods for determination of Dl’PH radical scavenging,reducing power,superoxide anion radical scavenging,hydroxyl radical scavenging, hydrogen peroxide scavenging,metal chelating and nitric oxide radical scavenging at the doses of 20.40.60.80 and 100μg/mL,respectively.3 -tocopherol with same concentration was used as a standard antioxidant.In vitro antimicrobial activity of B2 was determined by cup plate method in different concentration range of 10-100μg/mL.Results:The results indicated that dose dependent%reduction against DPPH radical,reducing power,superoxide anion radical scavenging,hydroxyl radical scavenging,metal chelating,hydrogen peroxide scavenging and nitric oxide radical scavenging by B2 andβ-tocopherol.Conclusions:It is concluded that cycloart 23-ene-3β,25 diol(B2) showed dose dependent antioxidant activity.B2 showed more DPPH radical scavenging,reducing power,superoxide scavenging,hydroxyl radical scavenging, metal chelating scavenging,hydrogen peroxide radical scavenging and nitric oxide radical scavenging activity thanβ-tocopherol and in case of antimicrobial activity B2 exhibited broad-spectrum activ ity against bacteria and strong activity against yeast type of fungi.
文摘Aims: The representativeness of the mandatory bacterial strains specified in European standards for in vitro assay of the bactericidal activity of antiseptics was evaluated by testing the activity of an antiseptic combining chlorhexidine digluconate 0.2% and benzalkonium chloride 0.5% against 21 additional bacterial strains, and the positive interaction between these two biocidal agents was assessed. Methods and Results: The bactericidal activity of the antiseptic solution used pure or diluted was assessed according to the European standards EN 1040 and EN 13727. The contact time was 1 min at 20°C. Interfering substances used in the EN 13727 assay were bovine serum albumin and sheep erythrocytes, simulating “dirty” conditions, and hard water. A reduction of colony-forming units by ≥5 log10 was deemed to meet the requirements to conclude bactericidal activity. Under “basic” conditions, the bactericidal activity of the antiseptic was observed against all four mandatory strains specified in the standards as well as against nearly all the additional strains tested, including most of those with acquired antibiotic-resistance. The positive interaction between the two biocidal agents was also confirmed. Under “dirty” conditions, the bactericidal activity of the antiseptic solution was maintained against all the mandatory strains and was reduced against only four of the additional strains tested. Conclusions: With regard to the antiseptic tested and under the experimental conditions described, bactericidal activity evidenced against the mandatory strains appeared to be representative of that manifested against a wide range of the main pathogenic bacteria. Reduced bacterial activity against some of the additional strains tested (e.g. Enterobacteriaceae) was observed under “dirty” conditions. Significance and Impact of the Study: EN 13727 with some experimental adjustments represents an additional appropriate standard that needs to be considered for mucocutaneous antiseptic assessment. However, it may be worth including other specific bacterial strains to those specified in the standard, when evaluating antiseptics intended for use in certain clinical situations.
文摘A new compound, 3,6,20（S）-trihydroxy- 12,23-epoxydammar-24-ene,6,20-di-O-β-D-glucopyranoside （1）, was isolated from the leaves of Panax ginseng C.A. Meyer, whose structural elucidation was carried out by means of spectral analysis （including IR, HR- FAB-MS and NMR）. This compound showed the moderate cytotoxic activities against U937 and HeLa cells by using the MTT method.
文摘Phytochemical investigation of the purified fractions of the active dichloromethane extract of Hysterionica pinifolia (Poir.) Baker led to the identification of five compounds. New acetylenic alcohol (E)-undec-3-en-5,7-diyne-1-ol (1) and three other compounds (3), (4), and (5) were reported for the first time in this species. Furthermore, forty-six components from the volatile fraction of H. pinifolia were identified. These compounds were elucidated using 1D and 2D NMR spectroscopy as well as MS-ESI and GC-FID-MS experiments. The dichloromethane extract, its fractions, and the methanolic extract were tested for insecticidal activity against Tribolium castaneum under laboratory conditions. The dichloromethane extract and the fraction F2 were found to be active, showing high larval mortality. The dichloromethane extract was also active against T. castaneum adults. The results have shown that H. pinifolia could be considered, in a near future, as a potential source for the development of a botanical insecticide for pest control.
基金Supported by the National Natural Science Foundation of China(Grant No.19935020)
文摘Nicotine [3-(1-methyl-2-pyrrolidinyl)-pyridine], a major alkaloid in tobacco products, has proven to be a potential genotoxic compound. Some polyphenolic compounds can suppress the DNA adduction, and hence act as the potential inhibitors of carcinogenesis. In this study, the inhibitory effects of three polyphenolic compounds, curcumin (diferuloylmethane), resveratrol (trans-3, 5, 4-trihydroxystilbene) and tea polyphenols, on the nicotine-DNA adduction have been investigated in vitro using radiolabelled nicotine and liquid scintillation counting (LSC) technique. Also, the inhibition mechanism of these chemopreventive agents in regard to the activity of the biotransformation enzymes, including cytochrome P450 (CYP450), cytochrome b5 (CYb5) and glutathione S-transferase (GST), has been studied. The results demonstrated that these three polyphenols induced marked dose-dependent decrease in nicotine-DNA adducts as compared with the controls. The elimination rate of adducts reached above 46% at the highest dose for all the three agents with 51.6% for resveratrol. Correspondingly, three polyphenols all suppressed CYP450 and CYb5, whereas curcumin and resveratrol induced GST. We may arrive at a point that the three polyphenols are beneficial to prevent the nicotine adduct formation, and thus may be used to block the potential carcinogenesis induced by nicotine.
基金This project was co-tbunded by the Ph.D Program of Ministry of Education, China （No. 20130008110003）, and the National Natural Science Foundation of China （No. 21172254）.
文摘The novel fungicidal agents, （E）-5-[1-（2-oxo-l-oxaspiro[4,5]dec/non-3-en-3-yl）ethylidene]-2-aminoimidazolin- 4-one derivatives, were designed and synthesized in moderate to excellent yields in four steps using a-hydroxyketone and diketene as raw materials and characterized by HR-ESI-MS, 1H NMR and X-ray diffraction. The preliminary bioassay showed that some of these compounds, such as 5e, 6a, 6e, and 7h exhibit 87.8%, 91.3%, 89.9% and 87.8% inhibition rates against Sclerotinia scleotiorum, 3b, 3c, 4c and 7h exhibit 96.4%, 92.5%, 90.3% and 76.9% inhibition rates against Phytophthora capsici at the concentration of 50 μg/mL, respectively. These compounds exhibited significant fungicidal activities against S. scleotiorum and P. capsici with EC50 values of 2.56 --11.60 μg/mL, and compounds 6e and 7h exhibited weak inhibition against the spore germination of S. scleoti- orum, while the spore germination ofP. capsici was strongly inhibited by compound 7h solution. Scanning electron microscopy （SEM） and transmission electron microscopy （TEM） observation indicated that compound 7h had a significant impact on the structure and function of the hyphal cell wall ofP. capsici mycelium.
