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1.
Prep Biochem Biotechnol ; 52(9): 1060-1068, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35098874

RESUMO

Here, the extraction of total flavonoids from Tremella fuciformis (TF) by aqueous two-phase extraction combined with ultrasound is presented. The extraction was optimized via a single-variable approach using the variables of mass fraction of ethanol and NaH2PO4, ultrasonication time, and TF sample amount. Response surface methodology (RSM) was then applied to determine the best conditions for extraction using the following three key parameters: ultrasonication time, ethanol mass fraction, and NaH2PO4 mass fraction. The optimum conditions were as follows: an aqueous two-phase system of ethanol/NaH2PO4, an ethanol mass fraction of 23%, a NaH2PO4 mass fraction of 27.18%, and an extraction time of 8.25 min. Under these conditions, the maximum extraction rate of total flavonoids was 0.158 mg/g. The scavenging rates for superoxide anion and hydroxyl radical, as well as the antioxidant activity of total flavonoids in TF, were studied. Total flavonoids from TF showed some scavenging ability, but the scavenging effects were lower than those of vitamin C (Vc) at the same concentrations. Nevertheless, ultrasound-assisted two-phase extraction was considered an efficient and rapid method that can be used to extract total flavonoids from TF.


Assuntos
Antioxidantes , Flavonoides , Antioxidantes/farmacologia , Ácido Ascórbico , Basidiomycota , Etanol , Radical Hidroxila , Extratos Vegetais , Superóxidos , Água
2.
Nat Prod Res ; 36(1): 287-294, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32538675

RESUMO

Chemical investigation into the stems of the medicinal plant Schisandra sphaerandra led to the isolation and identification of a new dibenzocyclooctadiene lignan sphaerandrin A (1) and 11 known ones gomisin B (2), schirubrisin B (3), kadsuphilin B (4), schizandrin (5), benzoylgomisin Q (6), angeloylgomisin Q (7), gomisin G (8), schisanwilsonin O (9), isogomisin O (10), schisantherin D (11), and wuweizisu C (12). The structure of the new compound was elucidated by comprehensive spectroscopic methods including 1 D/2D NMR, HRESIMS, and CD spectrometry. To the best of our knowledge, compounds 2 - 11 were obtained from this species for the first time. All the compounds were evaluated for the cytotoxic activity against the triple-negative breast cancer cell lines MDA-MB-231 and HCC-1937.


Assuntos
Carcinoma Hepatocelular , Lignanas , Neoplasias Hepáticas , Plantas Medicinais , Schisandra , Ciclo-Octanos , Humanos , Lignanas/farmacologia , Caules de Planta
3.
Ying Yong Sheng Tai Xue Bao ; 27(9): 3029-3034, 2016 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-29732869

RESUMO

In order to reveal the toxicity effect and risk of co-exposure of Cu and chlorpyrifos in the current soil environment of China, using the earthworm Eisenia fetida as model organism, the effect of single, and co-exposure of Cu and chlorpyrifos on the growth and antioxidant response of earthworm were analyzed by using the methods of filter paper test and artificial soil test. The results showed that the growth rate of earthworm tended to decrease with the increase of single exposure concentrations of Cu and chlorpyrifos in artificial soil test. The mass of earthworm had a relatively flat changing rate with the co-exposure of Cu and chlorpyrifos. Using the addition of probability, the q values of different concentration groups of Cu and chlorpyrifos on the earthworm mass were less than 0.55, which indicated significant antagonistic effect. The joint effect of Cu and chlorpyrifos on the activities of CAT and SOD indicated antagonistic effect in filter paper test, while the effects of co-exposure of Cu and chlorpyrifos on the contents of GSH and MDA showed a synergy effect of low concentrations and antagonism effect of high concentrations.


Assuntos
Clorpirifos/toxicidade , Cobre/toxicidade , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/toxicidade , Animais , China , Solo
4.
Huan Jing Ke Xue ; 36(1): 280-5, 2015 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-25898676

RESUMO

Combined pollution of heavy metal and pesticide had posed a serious threat to soil ecology and human living environment. As two common types of pollutants in soil environment, the environmental effects of combined pollution of Cu and chlorpyrifos are worth for attention. The acute lethal effects and avoiding behavior of single and co-exposure of Cu and chlorpyrifos on earthworms were analyzed by using the methods of standard OECD filter paper test and artificial soil test. Results showed that the LC(50,48 h) and LC(50,14 d) of the acute toxicity of Cu on earthworm in filter paper test and in artificial soil test were 2.23 microg x cm(-2) and 496.05 mg x kg(-1), respectively. The LC(50,48 h) and LC(50,14 d) of the acute toxicity of chlorpyrifos on earthworm in filter paper test and in artificial soil test were 5.94 microg x cm(-2) and 186.07 mg x kg(-1), respectively. In filter paper test and artificial soil test, the joint acute toxicity of Cu and chlorpyrifos showed an additive effect while the concentration was 1:1. The type of combined effects of co-exposure of Cu and chlorpyrifos was synergistic effect and antagonistic effect in filter paper test and artificial soil test, respectively, while the toxicity was 1:1. The results of avoidance behavior test showed that the joint effect of Cu and chlorpyrifos on the avoidance behavior of earthworms was antagonistic.


Assuntos
Clorpirifos/toxicidade , Cobre/toxicidade , Oligoquetos/efeitos dos fármacos , Resíduos de Praguicidas/toxicidade , Poluentes do Solo/toxicidade , Animais , Dose Letal Mediana , Metais Pesados/toxicidade , Solo/química
5.
Huan Jing Ke Xue ; 34(9): 3386-90, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24288980

RESUMO

Tetracycline antibiotics are a group of antibiotics which has been extensively used in most countries and are also the most widely used veterinary drugs and food additives in aquaculture and livestock industries of China. Because the substances are poorly adsorbed in the gut of animals and are only partially eliminated in sewage treatment plants, the antibiotics and their metabolites reach surface water where they may affect the aquatic organisms and human health. Herein, using green algae as test organisms, we studied the effects of tetracycline (TC), chlortetracycline (CTC) and deoxyteracycline (DC) on the cell permeability and growth inhibition of Chlorella pyrenoidosa and Scenedesmus obliquus. After 96 h of antibiotics exposure, the permeability of the cell membranes of both algae was decreased in the entire concentration range of doxycycline and was increased after exposure to a low concentration of tetracycline and chlortetracycline, then was decreased with the increase of the two antibiotics concentrations. The growth inhibiting effects of these three antibiotics on Chlorella pyrenoidosa and Scenedesmus obliquus were in an order of DC > TC > CTC. The ecotoxic response of Scenedesmus obliquus to tetracycline antibiotics was more sensitive than Chlorella pyrenoidosa.


Assuntos
Antibacterianos/farmacologia , Chlorella/efeitos dos fármacos , Scenedesmus/efeitos dos fármacos , Tetraciclinas/farmacologia , China , Testes de Toxicidade
6.
Chem Biodivers ; 9(12): 2754-60, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23255445

RESUMO

Two new labdane diterpenoids, namely hedycoronals A and B (1 and 2, resp.), were isolated from the rhizomes of Hedychium coronarium, together with eight known diterpenoids, 4-11, and a known diarylheptanoid, 3. The structures of 1 and 2 were established by detailed interpretation of their 1D- and 2D-NMR spectra and HR-ESI-MS data. Inhibitory activities against human umbilical vein endothelial cells (HUMECs) proliferation and cytotoxic activities against four cancer cell lines were assessed for all the isolates. Most of these metabolites showed moderate or potent cytotoxic activities against four cancer cell lines. Moreover, compounds 3 and 8 exhibited promising inhibitory activities against HUMECs with the IC(50) values of 6.4 to 3.3 µM.


Assuntos
Diarileptanoides/química , Diterpenos/química , Zingiberaceae/química , Inibidores da Angiogênese/química , Inibidores da Angiogênese/isolamento & purificação , Inibidores da Angiogênese/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Diarileptanoides/farmacologia , Diarileptanoides/toxicidade , Diterpenos/farmacologia , Diterpenos/toxicidade , Células Endoteliais da Veia Umbilical Humana , Humanos , Espectroscopia de Ressonância Magnética , Conformação Molecular , Rizoma/química
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