排序方式: 共有34条查询结果,搜索用时 31 毫秒
1.
微波消解-石墨炉原子吸收光谱法测定蜂胶中铅 总被引:1,自引:0,他引:1
付文燕 《理化检验(化学分册)》2010,(3)
提出了石墨炉原子吸收光谱法测定蜂胶中铅含量的方法,样品采用微波消解,用磷酸二氢铵基体作为改进剂,方法的精密度(n=7)在1.1%~1.3%之间,回收率在91.8%~101.9%之间。 相似文献
2.
一阶导数分光光度法测定蜂胶保健品中黄酮的探导 总被引:5,自引:0,他引:5
用一阶导数分光光度法测定了蜂胶保健品中黄酮。以芦丁为对照品,测定了蜂胶保健品中总黄酮总量。芦丁浓度在0-20mg/L内,一阶导数值与其浓度具有良好的线性关系,其回归方程为y=-0.00061-0.0065x,相关系数r=0.9998。方法简便、快速、准确。 相似文献
3.
Karina Basso Santiago Gilce Maria Piana Bruno José Conti Eliza de Oliveira Cardoso Bruna Fernanda Murbach Teles Andrade Mirella Rossitto Zanutto 《Natural product research》2018,32(12):1441-1445
Propolis is a bee product with several biological properties. This study aimed at investigating a propolis-containing mouthwash, its organoleptic properties, microbial contamination and its antibacterial action in vitro. This mouthwash was assessed in vivo to control dental plaque in humans. The presence of microorganisms was analyzed and the minimum inhibitory concentration against Streptococcus mutans was determined. A comparative study was done in vivo using propolis, chlorhexidine, and propolis plus chlorhexidine in lower concentrations for 14 days. Dental plaque was analyzed by the Patient Hygiene Performance (PHP) index. The odontological product was yellow, cloudy, free of microbial contamination, and exerted an inhibitory action in vitro. Individuals who used a propolis-containing mouthwash for 14 consecutive days in combination or not to chlorhexidine showed a similar PHP index to chlorhexidine alone. The product exerted an antibacterial action in vitro and in vivo, exhibiting a positive action in the control of dental plaque. 相似文献
4.
MSPD procedure for determining buprofezin,tetradifon, vinclozolin,and bifenthrin residues in propolis by gas chromatography–mass spectrometry 总被引:1,自引:0,他引:1
dos Santos TF Aquino A Dórea HS Navickiene S 《Analytical and bioanalytical chemistry》2008,390(5):1425-1430
A simple and effective extraction method based on matrix solid-phase dispersion (MSPD) was developed to determine bifenthrin,
buprofezin, tetradifon, and vinclozolin in propolis using gas chromatography–mass spectrometry in selected ion monitoring
mode (GC–MS, SIM). Different method conditions were evaluated, for example type of solid phase (C18, alumina, silica, and Florisil), the amount of solid phase and eluent (n-hexane, dichloromethane, dichloromethane–n-hexane (8:2 and 1:1, v/v) and dichloromethane–ethyl acetate (9:1, 8:2 and 7:3, v/v)). The best results were obtained using 0.5 g propolis, 1.0 g silica as dispersant sorbent, 1.0 g Florisil as clean-up sorbent,
and dichloromethane–ethyl acetate (9:1, v/v) as eluting solvent. The method was validated by analysis of propolis samples fortified at different concentration levels
(0.25 to 1.0 mg kg−1). Average recoveries (four replicates) ranged from 67% to 175% with relative standard deviation between 5.6% and 12.1%. Detection
and quantification limits ranged from 0.05 to 0.10 mg kg−1 and 0.15 to 0.25 mg kg−1 propolis, respectively. 相似文献
5.
Mozhgan Afkhamizadeh Robab Aboutorabi Hassan Ravari Mohsen Fathi Najafi Adineh Javadian Langaroodi 《Natural product research》2018,32(17):2096-2099
In this randomized controlled trial, diabetic patients with foot ulcers (Wagner grades 1 and 2) were randomly assigned to conventional therapies for diabetic foot ulcer plus topical propolis ointment (5%; twice daily) or conventional therapies alone. The process of ulcer healing was observed during 4 weeks and compared between the two groups regarding the size, erythema, exudates, white blood cell (WBC) count and erythrocyte sedimentation rate (ESR). The process of ulcer size reduction during the four-week period of study was significantly different between the groups. However, this difference was not significant between the third and fourth weeks. There was no significant difference between two groups regarding erythema and exudate reduction as well as WBC count and ESR. Administration of topical propolis ointment in addition to the conventional treatments of diabetic foot ulcer could reduce the size of ulcers with Wagner grades 1 and 2. 相似文献
6.
Separation of flavonoids and phenolic acids from propolis by capillary zone electrophoresis 总被引:3,自引:0,他引:3
Volpi N 《Electrophoresis》2004,25(12):1872-1878
The simultaneous determination of twelve different flavonoids, pinocembrin, acacetin, chrysin, rutin, catechin, naringenin, galangin, luteolin, kaempferol, apigenin, myricetin, and quercetin, two phenolic acids, cinnamic acid and caffeic acid, and one stilbene derivative, resveratrol, in propolis extracts used in medicine has been investigated by capillary zone electrophoresis (CZE). With a buffer constituted by sodium tetraborate 30 mM, pH 9.0, and 15 kV applied voltage, the 15 polyphenols were separated on an uncoated fused-silica capillary within 40 min using normal polarity. Under the experimental conditions used, a linear relationship was calculated between the CZE migration times and the molecular weight of polyphenols' expression of the increasing amount of their hydroxyl groups and polarity. Regression equations revealed a linear relationship (correlation coefficients > 0.97) between the peak area of each polyphenol species and their concentration, from 6 to 120 ng. The levels of analytes in three different propolis extracts, ethanolic, aqueous-ethanolic and aqueous-glycolic, used to prepare various commercial medicinal products, were determined. The aqueous-ethanolic propolis extract showed a great percentage of caffeic acid, galangin, quercetin, and chrysin, whilst the ethanolic preparation was composed of a great amount of resveratrol, chrysin, and caffeic acid. On the contrary, the aqueous-glycolic propolis preparation was composed of approx. 11% of caffeic acid and a low amount of the other identified flavonoids due to the presence of approx. 85% of nonidentified compounds. CZE represents a valuable method for the qualitative and quantitative assay of the most relevant polyphenol components of propolis, representing an alternative to obtain typical fingerprints of propolis and a reliable identification of a large number of propolis polyphenolic species. 相似文献
7.
Chen F Chen L Wang Q Zhou J Xue X Zhao J 《Analytical and bioanalytical chemistry》2009,393(3):1073-1079
A rapid and reliable method was developed and applied for the simultaneous determination of 17 organochlorine pesticides (OCPs)
in propolis. After extraction with hexane and acetone (1:1, v/v), four sorbents (florisil, silica, graphitized carbon, and
tandem graphitized carbon plus florisil) were assayed for the clean-up step. The elution solvents hexane and ethyl acetate
(1:1, v/v), hexane and dichloromethane (3:7, v/v), and ethyl acetate and hexane (2:8, v/v) were studied. The results showed
that the combination of the tandem graphitized carbon and florisil cartridge with the elution solvent of 6mL of ethyl acetate
and hexane (2:8, v/v), which was capable of eliminating matrix interference and providing colorless eluates, was the most
efficient clean-up procedure for propolis extracts when testing for OCPs. The analytical technique employed was gas chromatography
with electron capture detection (GC–ECD). The correlation coefficients from linear regression for the analyzed concentrations
(5∼100 μg/kg) were >0.9961. The limits of detection (LODs) varied between 0.8 μg/kg for 4,4′-DDE and 11.4 μg/kg for endosulfan
II, and the limits of quantitation (LOQs) ranged from 2.6 to 38.1 μg/kg. The average recoveries varied between 62.6 and 109.6%.
Relative standard deviations (RSD%) ranged from 0.8 to 9.4%. Sample analysis indicated that 4,4′-DDE was detected more often
in propolis than other pesticides, such as β-HCH, δ-HCH and heptachlor.
Figure GC-ECD chromatogram of a standard solution with 0.1 mg/L of OCPs 相似文献
8.
9.
Mechanisms underlying the cytotoxic effect of propolis on human laryngeal epidermoid carcinoma cells
Yahima Frión-Herrera Alexis Díaz-García Jenny Ruiz-Fuentes Hermis Rodríguez-Sánchez 《Natural product research》2018,32(17):2085-2091
Propolis has been used as a traditional remedy for centuries because of its beneficial effects, including anticancer properties. The aim of this study was to compare the cytotoxic mechanism of Cuban red propolis (CP) and Brazilian green propolis (BP) on human laryngeal carcinoma (HEp-2) cells. Cell viability, leakage of lactate dehydrogenase, fluorescence staining, mitochondrial membrane potential (ΔΨm) and the expression of pro/anti-apoptotic genes were assessed. Cell viability and cytotoxic assays suggested a dose-dependent effect of CP and BP extracts with a possible association of intracellular reactive oxygen species production and decreased ΔΨm. Both samples induced apoptosis via activation of TP53, CASP3, BAX, P21 signalling, and downregulation of BCL2 and BCL-XL. CP exerted a higher cytotoxic effect than BP extract. Our findings suggest further investigation of the main components of each propolis sample, what may lead to the development of strategies for the treatment of laryngeal cancer. 相似文献
10.
A. Ramadan G. Soliman Sawsan S. Mahmoud Salwa M. Nofal Rehab F. Abdel-Rahman 《Journal of Saudi Chemical Society》2012,16(1):13-21
The possible toxicological effects and in vitro antioxidant activity of the ethanolic extracts of Crocus sativus and Propolis were investigated. Both extracts did not cause any mortalities or signs of toxicity in mice when administered orally at doses up to 5 g/kg b.wt. In the sub-chronic study; the tested extracts did not produce any significant change in liver and kidney functions of rats, following oral administration for 8 successive weeks at doses of 500 mg/kg b.wt. of each. Propolis showed remarkable in vitro antioxidant activity at concentrations of (40–100 mg/ml). In contrast, the ethanolic extract of C. sativus ethanolic extract showed weak antioxidant activity in concentrations of (1–10 mg/ml) while at concentrations of (20–100 mg/ml) failed to exhibit any antioxidant activity. It was concluded that: both extracts were non-toxic, as they did not cause any mortalities or signs of toxicity in mice when administered orally at doses up to 5 g/kg b.wt. Daily oral administration of C. sativus, Propolis ethanolic extracts alone or in combination for 8 successive weeks to rats was quiet safe and didn't cause any toxic changes in liver and kidney. Antioxidant study showed that Propolis ethanolic extract was a more potent antioxidant than C. sativus extract. 相似文献