scholarly journals DETERMINATION OF CHLORPYRIFOS IN LETTUCE (LACTUCA SATIVA L.) BY MICROWAVE-ASSISTED EXTRACTION COUPLED WITH HEADSPACE SINGLE DROP MICROEXTRACTION

Author(s):  
Naruephon Watthanaphap ◽  
Surapol Natakankitkul ◽  
Nuchnart Jonglaekha

Objective: The objective of this research was to improve the method of extracting pesticide residue from vegetable by using microwave-assisted extraction, headspace single drop microextraction (MAE-HS-SDME) and analysed by gas chromatograph-mass spectrometer (GC-MS).Methods: Microwave-assisted extraction (MAE) coupled with headspace single drop microextraction (HS-SDME) was used for extraction of chlorpyrifos insecticide residues in lettuce. The optimum conditions for obtaining efficient extraction have been tried; kind and quantity of solvent, extraction time, microwave irradiation power, pH value and the amount of salt added in the sample followed the method of Plackett–Burman. Optimum conditions for efficient analysis were evaluated by using a central composite design (CCD) combined with a response surface methodology (RSM).Results: The optimum extract conditions from CCD for the MAE-HS-SDME method were: using 1.5 µl of n-butyl acetate, 460 W of the microwave power, 4.5 min of the extraction time, no pH adjustment and no salt addition. Verification of the optimized experimental conditions showed that validation of the determination coefficient ranges from the concentrations of 0.01 to 0.10 mg/l, equal to 0.999; the percentages of variation coefficient were ranges from 4.6 to 7.7%; the recoveries ranges from 70.0 to 79.5%; limit of detection was 0.003 mg/kg and limit of quantitation was 0.01 mg/kg.Conclusion: In this study, the MAE-HS-SDME method coupled with GC-MS was found most suitable for chlorpyrifos analysis. The results obtained from analyzing chlorpyrifos in lettuce samples indicated that this method is rapid, simple, sensitive, reducible cost and safety for the analyst and the environment.

2018 ◽  
Vol 15 (2) ◽  
pp. 6173-6185
Author(s):  
Vedashree M ◽  
Madeneni Madhava Naidu

The present study investigates optimum conditions for Microwave assisted extraction (MAE) of 6-gingerol. Ginger was dried using a cross flow dryer at 55 ± 2 0C for eight hours. Ginger powder was extracted at three different watts (400 W, 500 W, and 600 W), temperatures (50 0C, 60 0C, 70 0C) and time (10, 20, 30 min) for optimum yield.  6-gingerol content was found to be 21.15 ± 0.13 and 18.81 ± 0.15 mg/g in fresh ginger and dried ginger, respectively.  Optimized condition obtained by RSM for 6-gingerol was 400 W, 70 0C at 10 min extraction time.  The results of MAE are expressed by 2-D contour plot and response surface curve by keeping one variable constant which showed highest yield at 600 W, 70 0C for 30 min extraction time.  Microwave assisted extracts exhibited higher antioxidant activity in comparison with conventional extracts.


2010 ◽  
Vol 93 (3) ◽  
pp. 849-854 ◽  
Author(s):  
Xiaohua Xiao ◽  
Yi Yin ◽  
Yuling Hu ◽  
Gongke Li

Abstract A sensitive and accurate method consisting of microwave-assisted extraction (MAE) coupled with single drop microextraction (SDME) and HPLC was developed for the determination of four trace estrogen adulterants, including estriol (E3), estradiol (E2), ethinyl estradiol (EE), and estrone (E1), in different soybean dietary supplements. The samples were extracted by MAE; the extracts were cleaned up and enriched by SDME, and then analyzed by HPLC. The conditions of MAE were optimized, and the effects of solvent and extraction time in SDME on the enrichment capacity were studied. The enrichment factors of E3, E2, EE, and E1 under the optimized conditions were 247-, 335-, 316-, and 319-fold, respectively. The linear range of the MAE-SDME-HPLC method ranged from 5.0 to 180.0 g/L, and the detection limit from 1.1 to 1.2 g/L. The RSD ranged from 7.9 to 9.6. Three soybean dietary supplements, including oral liquid, capsule, and tablet forms, were analyzed. The spike recovery was more than 70, with RSD lower than 13.2. It was shown that the proposed method was accurate, sensitive, and suitable for the determination of trace analytes in complex samples.


2020 ◽  
Vol 7 (3) ◽  
pp. 10-19
Author(s):  
Zaldy Rusli ◽  
Bina Lohita Sari ◽  
Novi Fajar Utami ◽  
S Sabila

Binahong (Anredera scandens (L.) Moq.) leaves are one of the plants that empirically can be used for wound healing and contain flavonoids which have antibacterial and antioxidant activities. Determination of the optimum conditions of the Binahong leaf extraction process needs to be done to ensure the extraction quality of the Binahong leaves associated with the given activity. Microwave Assisted Extraction (MAE) is an extraction that utilizes microwave radiation to heat the solvent quickly and efficiently. This study aims to determine the most effective binahong leaf extraction conditions that produce optimal levels of flavonoids and antioxidant activity. The extraction process was carried out using the Microwave assisted extraction (MAE) method. Determination of optimum conditions is done based on Response Surface Method (RSM) with variable ethanol concentration (70%, 80% and 90%), extraction time (4, 12 and 20 minutes) and power (450, 600, and 800 watts) using Box- Behnken Design (BBD) with Design Expert 7.0 software. The extract quality parameters measured were total flavonoid levels and antioxidant activity. The results showed the optimum conditions with the BBD method were obtained at an ethanol concentration of 81.49%, extraction time of 13.84 minutes, and power of 626.19 watts with flavonoid levels of 3.8561% and antioxidant activity (IC50) of 95.51834 ppm with active categories.


Author(s):  
Widya Dwi Rukmi Putri ◽  
◽  
Eko Isro Riyanto ◽  
Almaria Heliana ◽  
Ambo Wellang ◽  
...  

Abstract Gembili (Dioscorea esculenta) is a tuber-producing plant containing 14.63% inulin, a Water-Soluble Polysaccharide (WSP). This study aims to determine the optimum point of material to solvent ratio and Microwave-Assisted Extraction (MAE) time needed to extract gembili WSP, and determine the WSP's characteristics produced. The optimization process uses the Response Surface Methodology-Central Composite Design (RSM-CCD) with Design Expert 7.0 software. The material to solvent ratio's minimum and maximum points are 1:25 g/L and 1:45 g/L, while the minimum and maximum points of extraction time are 20 minutes and 40 minutes. This study observed 13 experimental combinations and responses from gembili WSP yield, WSP powder inulin levels, and WSP solubility. The results showed that the optimum conditions of material to solvent were at a 1:33.81 g/mL ratio, and the extraction time was 29.26 minutes. This optimum condition resulted in 32.42% WSP yield, 40.8% inulin content in WSP powder, 26.98% WSP solubility, 12.24% WSP water content, and 49.3 cp WSP viscosity. These results indicate that extraction using a microwave can increase WSP's rich inulin yield from gembili tubers. Keywords: gembili, inulin, microwave, optimization, Water-Soluble Polysaccharides


2012 ◽  
Vol 518-523 ◽  
pp. 430-435 ◽  
Author(s):  
Hai Rong Guo ◽  
Shao Ying Ma ◽  
Xiao Fei Wang ◽  
Er Fang Ren ◽  
Yuan Yuan Li

Microwave-assisted extraction (MAE) was used to extract chlorophylls from filter mud. Ethanol was used as the solvent. The optimal conditions for the MAE of chlorophylls were concluded from the study as the irradiation time, 50 s, the ratio of liquid to solid, 8:1 (mL/g), the extraction temperature, 40 °C, and the extraction time, 60 min. Compared with conventional extraction, the MAE of chlorophylls from the filter mud was more effective. The extraction time for MAE was 60 min with 0.277 mg/g chlorophyll yield, while conventional extraction needed 240 min with only about 0.259 mg/g chlorophyll yield. The Ultraviolet Absorption Spectra of the extracted chlorophylls showed that there was a strong absorption peak at about 663 nm. C=N, Mg-N and C-N was not seen existed from the infrared spectroscopy probably because that the mixed extracts were not purified and the chlorophyll content was less.


2018 ◽  
Vol 69 (3) ◽  
pp. 260 ◽  
Author(s):  
H. N. Özbek ◽  
D. Koçak Yanık ◽  
S. Fadıloğlu ◽  
H. Keskin Çavdar ◽  
F. Göğüş

Soxhlet and microwave assisted extraction (MAE) methods were used to obtain non-polar compounds from pistachio hull. MAE parameters (liquid to solid ratio, microwave power, and extraction time) were studied to obtain maximum extraction yield. The optimal conditions were found to be liquid to solid ratio of 15:1 (v/w), microwave power of 250 W and extraction time of 12.5 min. The extraction yields were 9.81 and 9.50% for MAE and Soxhlet methods, respectively. The total phenolic content, antioxidant activity and tocopherol content of the extract obtained by MAE was found to be significantly higher than those of the Soxhlet extract (p < 0.05). The results showed that the extract contained α-tocopherols (567.65 mg/kg) and oleic acid (48.46%) as the major tocopherols and fatty acids. These findings propose that hull extracts can be considered as a good source of natural bioactive compounds and MAE can be a good alternative to the traditional Soxhlet method.


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