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Astragalus from different habitats in the study of organochlorine pesticide residues in_438

By Jerome Bailey,2014-10-30 10:38
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Astragalus from different habitats in the study of organochlorine pesticide residues in_438

    Astragalus from different habitats in the study of organochlorine pesticide residues in

     Abstract Objective To evaluate the different origin of the astragalus of organochlorine pesticide residues in medicinal quality evaluation. Methods water extraction

    system, acetone, dichloromethane liquid-liquid distribution,

    concentrated sulfuric acid sulfonation purification technology, flexible quartz capillary column (30 m × 0.32 mm

    × 0.25 μm) SE 54, GC ECD detection of organochlorine

    pesticide residues . Results The minimum detection limit is 0.1 ~ 0.5ng / g, the recovery was 72.6% ~ 114.8%; Gansu, Inner Mongolia and other main origin of organochlorine pesticide residues in Astragalus is far below the "Chinese Pharmacopoeia" standard. Conclusion A set of simple, workable detection of Radix Astragali organochlorine pesticide residues analysis.

     Key words capillary gas chromatography; organochlorine pesticides; Astragalus; residues

     Study on Residues of Organochlorine Pesticides in Radix

    Astragali Samples from Different Field Origins

     Abstract: ObjectiveTo program a quality evaluation of organochlorine pesticides residue on Radix Astragali produced from different places. MethodsSonication extraction system was used, in which acetone was the extractant. Based on salting

    out principles, sodium chlorine was added to the extractant to separate the pesticides. Simultaneously, CH2Cl2 was also added to carry out liquid extraction, then it was purified by dense sulphuric acid, and finally detected by GC ECD. ResultsThe

    detection limits were 0.1 ~ 0.5 ng / g, recoveries of organochlorine pesticides were 72.6% ~ 114.8% . Radix Astragali produced from Gansu, Neimeng ect were more lower than the standard of pharmacopeia.ConclusionA simple and

    handling analytical method to detect the organochlorine pesticides of Radix Astragali has been established.

     Key words: Capillary gas chromatography; Organochlorine pesticides; Radix Astragali; Residue

     With the "return to nature" concept of the continuous deepening of the Chinese medicine industry has been greater opportunities for development. But one of the bottlenecks impeding the development of Chinese medicine is the cultivation of non-standard Chinese herbal medicine, heavy

    metals, pesticide levels exceeded. The only way to solve this problem is to carry out the standardized GAP planting and management, of which one of the main elements of the establishment of pesticide residues in Chinese herbal medicine effective control method. In this study, the different origin of the astragalus by organochlorine pesticide residues testing, with a view to establish a set of simple, operable Radix Astragali organochlorine pesticide residues analysis.

     An instrument and reagent

     United States Varian cp3800 gas chromatograph, 63Ni ECD electron capture detector, 1177 injector; KQ 250E

    Ultrasonic Cleaner; LDZ5 2 low self-balancing centrifuge;

    ER 52AA rotary evaporator.

     Radix Astragali by Tianjin Taiping Group of Inner

    Mongolia Branch available; 666 (BHC) (α BHC, β BHC, γ

    -BHC, δ BHC), DDT (DDT) (PP ' DDE, PP' DDD, OP '

    DDT, PP' DDT), and PCNB (PCNB); were purchased from China, and biological products; other reagents were analytical pure.

     2 method [1 ~ 3]

     2.1 Preparation of reference substance solution

     2.1.1 Preparation of reference substance stock solution precision that take 666 (BHC) (α BHC, β BHC, γ

    BHC, δ BHC), DDT (DDT) (PP ' DDE, PP' DDD , OP'-DDT,

    PP ' DDT), and PCNB (PCNB) amount of pesticide reference standards, using petroleum ether (60 ~ 90 ?) were made per

    milliliter contains about 4 ~ 5 μg of the solution.

     2.1.2 Preparation of mixed reference substance precise amount of liquid reserves to take the above-mentioned stock

    solution 0.5 ml, set in 10 ml Liang Ping, using petroleum ether (60 ~ 90 ?) was diluted to scale, shake, that is, too.

     2.1.3 Preparation of mixed precision the amount of reference substance solution to take the above-mentioned

    reference substance stock solution mixed with petroleum ether (60 ~ 90 ?) were made with 0,1,5,10,50 μg per liter of

    solution, that is, too.

     2.2 Preparation of solution for the test items

     2.2.1 Astragalus extract taken for the test materials at 60 ? drying 4 h, crushed into powder, take about 2 g, precision that set, and placing 100 ml bottle with cone-shaped

    plug, add water, soaked in 20 ml overnight, precision plus acetone 40 ml, said that given the weight, ultrasound

    treatment 30 min, let cool, then filled with acetone that will reduce the weight of the weight loss, combined with sodium chloride of about 6 g, precision plus dichloromethane 30 ml, said that given the weight of , ultrasound treatment 15 min,

    and then said that given the weight loss with dichloromethane make up less weight, put it aside, will quickly moved into the organic phase with anhydrous sodium sulfate amount of 100 ml bottle with cone-shaped plug, placed 4 h. Reposted elsewhere in the paper for free download http://

     2.2.2 the amount of clean precision to take 35 ml, at 40 ? water bath, concentrated on the vacuum to nearly dry, add a small amount of petroleum ether (60 ~ 90 ?) such as the

    former repeated operations to methylene chloride and acetone

    addition to the net, with petroleum ether ( 60 ~ 90 ?)

    dissolved and transferred to a 10 ml centrifuge tube with plug scale, add petroleum ether (60 ~ 90 ?) Precision diluted to 5

    ml, carefully adding sulfuric acid 1 ml, Zhen Yao 1 min,

    centrifuged (3 000 r / min) 10 min. Precise amount of the supernatant 2 ml, set a scale enrichment bottle, connect rotary evaporator, 40 ? under (or nitrogen) will be

    concentrated to an appropriate solution, precision diluted to 1 ml, which was.

     2.3 The chromatographic conditions for the elastic quartz capillary column (30m × 0.32mm × 0.25μm) SE 54; inlet

    temperature of 230 ?, detector temperature 300 ?, splitless;

    programmed temperature: Initial 100 ?, 10 ? per minute up to

    220 ?, liters per minute, 8 ? to 250 ?, maintained 25 min;

    carrier gas: high purity N2, flow rate: 120 ml / min.

     3 Results

     3.1 The linear relationship of the study were drawn the above-mentioned series of concentrations of mixed-precision

    reference substance solution 1 μl injected into gas

    chromatograph, each concentration measured three times, with an average peak area of the vertical axis, the concentration of abscissa to calculate the regression equation. Table 1.

     Table 1 of organochlorine pesticides standard working curve (omitted)

     3.2 The detection limit for the test product solution according to preparation method, without a blank sample solution prepared Radix Astragali, precision drawing a blank

    sample solution, organochlorine pesticides mixed reference substance solution (1μg / L) 1 μl into the gas

    chromatograph, the measured minimum detectable limit (ng / g). The results in Table 2.

     Table 2 The detection limit determination results

    (omitted)

     3.3 The recovery of experimental medicine that Astragalus check (northern Shaanxi) 10 g, according to 9 were prepared for the test solution were added to a certain amount of mixed reference substance solution, add 3 levels, each level of

    three samples, according to the law for the test preparation materials solution, measured to calculate recovery. The results in Table 3.

     3.4 Determination of the different samples of Radix Astragali origin, according to experimental methods for the

    test materials prepared by solution, using GC ECD

    determination. Results of Table 4.

     Table 3 Astragalus recovery of organochlorine pesticides (omitted)

     Table 4 Astragalus different origin of organic chlorine pesticide residues (abbreviated)

     3.5 Results

     3.5.1 we can see from the table a mixture of

    organochlorine pesticides in the reference substance solution at 0 ~ 50 μg / L concentration range, a linear relationship was good.

     3.5.2 we can see from Table 4 for the Chinese medicinal

    herbs Astragalus organochlorine pesticide residues, due to the different origin, derived from residues of organic chlorine is not the same, and some even vary widely. This may well be with the local soil, air-related; the other hand, also in the

    cultivation of medicinal herbs Astragalus whether norms.

     3.5.3 The results indicate that in the selected samples are able to detect the organochlorine pesticide residues, but the residues are very low, much lower than the 2005 edition of

    "Chinese Pharmacopoeia" requirement (total 666 ? 0.2 mg / kg,

    the total DDT ? 0.2 mg / kg, PCNB ? 0.1 mg / kg).

     4 Discussion

     Extracted using different methods, the results do not differ greatly. In this study, the ultrasonic oscillator

    selected extracts only 15 ~ 30 min, while the conventional Soxhlet extractor extract Ze Xu 8 h. And with the Soxhlet extractor extraction method compared to ultrasonic extraction method is fast, simple and advantages of high recovery rate,

    more suitable for the extraction of plant samples.

     Sulfonation method used in this experiment to remove the operation of sub-funnel directly to concentrated sulfuric acid by adding concentrated liquid extract, the reduction of experimental steps to improve the safety and accuracy of the experiment.

     Experiment using petroleum ether, acetone and other reagents contain many impurities, experiments should be re-

    distilled them, and by gas chromatography analysis until no impurity peaks in the chromatogram appeared before use.

     The present study, SE 54 (30 m × 0.32 mm × 0.25 μm)

    fused silica capillary column, in this experimental condition, the right of organochlorine pesticides can be a better separation.

     References

     [1] Wang Li, Chen Jianming, Zhang Shuming.

    Organochlorine pesticide residues by gas chromatography detection method [J]. Chinese herbal medicine, 1998,29 (6): 381.

     [2] Han Guiru, Chen Tai-ping, Yang Jian-hong, et al.

    Medicine residues of organochlorine pesticides in the study [J]. Chinese Journal of Traditional Chinese Medicine, 1996,21

(10): 591.

     [3] Qing-Min Li, Jun Zhang. Fresh ginseng in the detection of organochlorine pesticides in 666 [J]. Chinese Journal of Traditional Chinese Medicine, 1996,21 (10): 162. Reposted elsewhere in the paper for free download http://www.hi138. com

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