جستجوی مقالات مرتبط با کلیدواژه "استخراج" در نشریات گروه "پزشکی"

Optimizing DNA extraction for the preservation of telomere length – as a biomarker for ageing and vari-ous diseases – is highly important. Long-term stored blood samples are considered essential resources for genetic studies. In this study, different lysis buffers were used along with CTAB extraction buffer to inves-tigate the quality of extracted DNA and the effect of its accompanying inhibitors on quantitative PCR (q-PCR) in telomere studies.

DNA extraction was performed using six RBC lysis buffers and CTAB-based extraction buffer. DNA integrity was evaluated by gel electrophoresis, quantity by absorbance at 260 nm and its purity with expected values of 1.8 and 2-2.2 for the ratios of A260/A280 and A260/A230. The quantitative effect of each buffer in q-PCR and the repeatability of the results were assessed by calculating the reaction efficiency, coefficient of determination (R2), and percentage of coefficient of variation (%CV).

Buffer number 5 (10 mM Tris-HCl, pH 7.6, 50 mM NaCl) yielded the highest amount of DNA extraction (324.93 ng/ml, %CV 11.53). All the extracted DNA samples were pure, as indicated by the acceptable A260/A280 and A260/A230ratios (p>0.05). Gel analysis revealed that the extracted DNA of all the buffers ex-cept one was intact. The DNA molecule extracted with buffer number 1 (155 mM NH4Cl, 10 mM KHCO3, and 5 mM EDTA) showed the best performance in q-PCR for HBG gene (efficiency=0.126, R2=0.97) and telomere (efficiency=0.99, R2=0.99).

The DNA molecule extracted from frozen blood samples by buffer number 1 showed the least q-PCR inhibition for telomere study.

Due to the unfavorable effects of synthetic antioxidants, the use of various sources of plant antioxidants to retard or prevent oxidation of foods, especially oil-based or fat-based varieties, has today received considerable attention.

Inorder to extract the essential oil, water distillation method was applied and the extract of citron peel was obtained by ultrasound and maceration methods by using ethanol, methanol and water as solvents. Total phenolic compounds of the extracts and their antioxidant activities were measured. The chemical compounds in the extract and essential oil were identified by gas chromatography. Finally, the antioxidant effect on the stability of sunflower oil was investigated. The stability of oil to oxidation during storage for 5 days at 65 ° C was assessed using peroxide, anisidine, thiobarbituric acid, Tutox values and oxidative stability index.

The most amounts of phenolic compounds and antioxidant activity was absorved in ultrasonic-assisted ethanolic extract at 30 min. The extract concentration at 800 ppm was more effective to radical scavenging than the other concentrations. The major compounds of citron peel extract were nomilin and hesperidin. The results showed that the peroxide, anisidine, and totox value had an increasing trend over time. Ultrasonic-assisted ethanolic extract at 30 min showed the highest OSI.

The results of this study demonstrate the beneficial effects of the essential oil and extract from citron peel on sunflower oil stability and its superiority over synthetic antioxidants.

Collagen is a protein that constitutes a major component of connective tissue and has many applications in the medical and non-medical fields. The increase in the world population and the need for proteins have led to a special focus on seafood. Furthermore, jellyfish is a rich and renewable source of collagen. Therefore, many researchers have shown interest in collagen extraction from jellyfish. This study aims to extract and purify collagen from jellyfish Catostylus mosaicus.

Acid-soluble and pepsin-soluble collagens were extracted and purified using a membrane with a MWCO of 100,000 from jellyfish Catostylus mosaicus. Protein content, type, denaturation temperature, and functional groups of the extracted collagens were evaluated using spectrophotometer, electrophoresis, viscometry, and Fourier transform infrared (FTIR) spectroscopy, respectively.

The results showed that pepsin-soluble collagen extracted from the umbrella and arm of the Catostylus mosaicus jellyfish consisted of chains α and dimer β, and the yields of the pepsin-soluble collagens extracted from the jellyfish umbrella and arm were 14.58% and 12.8% of the dry weight. The results also showed that the denaturation temperature of collagen extracted from the jellyfish arm and umbrella were about 27.32  and 28.72 , respectively. The FTIR spectra of pepsin-soluble collagen from the jellyfish umbrella and arm were almost identical to other types of collagens.

The results show that this species of jellyfish can be used as a renewable marine source of collagen instead of other sources of collagens.

In the past decade, sulfated fucose-rich polysaccharides (fucoidan) have been much interested due to their diverse biological activities, including anticoagulant, antiviral, antitumor, anti-inflammatory, anti-blood lipid, antioxidant, gastric protection and therapeutic activities. In the present study, microwave was used as a green efficient technology for the extraction of bioactive compounds of fucoidan from Iranian macroalgae (Nizimuddinia zanardini). In addition, effects of microwave on chemical composition and antioxidant activity of fucoidan were assessed.

Fucoidan polysaccharides were extracted under optimized conditions of microwave power, processing time and temperature. The compound characteristics, including extraction efficiency, fucose content, sulfate content, uronic acid content and DPPH radical scavenging were assessed. Fourier-transform infrared spectroscopy was used at wavelengths of 400–4000 cm-1 at room temperature.

Results showed that microwave treatment was effective in improving the extraction yield of fucoidan. Fucoidan extraction yields under the microwave technique included 3.71 and 2.35%. The fucose content under the microwave technique (33.17%) was compared to that under the conventional technique (29.5%) with significant increases, indicating less thermal degradation of the polysaccharide structures under the microwave technique. The microwave improved fucoidan antioxidant activity by producing shorter chain polysaccharides.

In this study, fucoidan sulfated polysaccharides were extracted using microwave extraction technique in a much shorter time than the conventional extraction technique with higher efficiency and lower thermal degradation. In addition, the shorter process time decreased solvent use.

Plants have been always considered as one of the main raw materials to be used in food, pharmaceutical and cosmetic industries. Marine algae is a rich sources of bioactive compounds with antioxidant activity.

In this study optimization of extraction of antioxidant compounds including chlorophyll a and b, carotenoids and total phenolic contents of Caulerpa sertularioides has been carried out by microwave-assisted extraction, based on extraction time, microwave power, solvent type and solvent to sample ratio. Experimental design was performed by Design Expert with 25 runs and the amounts of antioxidant compounds were evaluated.

The results of chlorophyll a and b evaluation showed that among 4 studied factors only solvent type had significant effect (P<0.05). According to the results the optimum conditions of chlorophyll a and b extraction included methanol as solvent, microwave power of 180 watt, extraction time of 20 minutes and solvent to sample ratio of 12.5. Regarding carotenoid solvent was the only significant factor (P<0.05) and its optimum extraction conditions included methanol as solvent, microwave power of 90 watt, extraction time of 10 minutes and solvent to sample ratio of 5. Concerning total phenolic content none of the 4 parameters of extraction process had significant effect on its extraction (P>0.05).

According to the results of this study Caulerpa sertularioides is an important source of antioxidant compounds and by studying the effect of extraction factors on its antioxidant and phenolic compounds and determination of the optimum extraction conditions for each compound, this algae could be employed appropriately.

The aim of this research work is to optimize the extraction conditions of Scenedesmus Obliquus algae protein by enzymatic and alkaline methods using response surface technique and to investigate the extracted protein’s functional properties. Optimization of enzymatic protein extraction using Minitab software with central composite response surface methodolog was designed for enzyme to substrate ratio factors and enzyme’s effective time (cellulose enzymes and multi-enzymes under optimum pH conditions) followed by optimization of the best treatment for the maximum extraction efficiency in the shortest time and finally the extracted proteins were identified by electrophoresis. The results showed that, the higher the enzyme concentration, the higher the extraction rate and the protein extraction efficiency, therefore with an increase in the concentration from 4 to 6 μl/ml, the efficiency of the extraction is increased from 15.28 to 27.87 percent using multienzyme, and it increased from 16.88 to 21.42 percent using cellulase. The optimum conditions calculated at the highest concentration and lowest response time were 4 μg / ml for 2.34 hours. The results obtained from the chemical extraction of samples indicated that, the extraction efficiency was calculated as 19.13 percent. The results of electrophoresis analysis showed that the proteins extracted from this microalga contained 8 protein bands with molecular weight ranging from 20 to 110 kDa. Enzymatic extraction of proteins indicated a better yield as compared to chemical extraction and also considering the economical aspects this method of extraction is suggested.

Perpetration of samples is one of the most important stages needed for trace residue analysis of biological specimens when human exposure assessment is required. The samples preparation process makes the analyte get more purified and enriched as well as more compatible to the analysis instrument systems. The present study has concentrated on a systematic review of different articles published regarding the sample preparation methodologies of human biological samples.

In this systematic review, all articles related to the development of sample preparation for trace residue analysis of heavy metals in occupational biological samples published in English during 2009-2019, were considered. To meet the desired objective of the current study and facilitate the  related articles on physiochemical sample preparation methods accessibility combined keywords of Mesh and non-Mesh, without any limitation in the type of studies, the Pubmed, Web of Science, and Scopus were considered to be searched. Noteworthy, in this study, only the articles related to the workers’ biological samples were reviewed.

Based on the obtained results, after reviewing of the keywords trough websites, 2964 articles were identified. Then, the redundant papers were removed and59 articles were remained, based on their titles and abstracts,. After detailed review of selected articles, regarding the study criteria, 8 articles were selected for the final systematic review.  Five articles out of 8, (62.5%) were allocated to the development of sample preparation for mercury in biological samples. It is worth mentioning that the majority of biological samples were regarded to the urine samples (75%) in the current study. Based on the obtained results, Solid Phase Extraction (SPE), applied in 37.5% of studies, was a popular method used in sample preparation.

The development of sample preparation approaches indicates a great promise for specified methods with low costs and less extraction time when separating different heavy metals from complex matrices. These sample preparation and preconcentration techniques ease the analyses processes and provide the quantitative recoveries, higher sensitivity, and lower detection limits.

Antioxidants are molecules which able to control free radicals and prevent the oxidants of other molecules considering undesirable effects of synthetic anti oxidant. In recent years using of natural anti oxidant gets the great importance. The secondary metabolisms of plants are rich sources of phenol and flavonoids considered as the most important natural antioxidant.  

In this research, the optimization process of phenolic and flavonoids from Adiantum capillus-veneris L. carried out by ultrasound-assisted extraction (UAE) and central composite design (CCD).

Optimization process were performed with four indepent variables including, plant powder (0.1-0.9 g), volume of solvent (5-17 ml), sonication time (5–25 min) and temperature of ultrassonic bath (20-60 ºC) on five levels including 26 test with 2 repetition on central point. The total phenolic content and total flavonoid content, respectively, were accounted by using foline-ciocalteu and aluminum chloride colorimetric method.

At optimum conditions values of variables set at 0.7 g of plant powder, 16 ml of extraction solvent, 20 min for ultrasound waves and 40 ºC for ultrasonic bath.

The results show that the quadratic mathematical model has acted with high accuracy to predict the optimal values of the studied parameters. Under these conditions, the extraction efficiencies for total phenol and flavonoid compounds were 9.46 mg/g and 5.22 mg/g, respectively.

The amount of heavey metal elements in tea mighg have significant impact on human health. In the present study, the amount of heavy metal elements such as cadmium (Cd), lead (Pb), zinc (Zn), iron (Fe), aluminum (Al) and copper (Cu) in some imported tea samples and local tea samples cultivated in Iran have been evaluated.

The Tea samples were prepared by three different methods including Digestion, Brew and Infusion and the concentration of heavy metals in the prepared samples were measured by ICP-OES and ICP-MS.

Aluminum with a concentration of 853.9 µg/g and the cadmium element with the concentration of 0.99 µg/g were found to be the highest and lowest in the samples examind, respectively. Among the extraction methods, the concentration of extracted elements in digestion method was significantly higher than other methods. The statistical analysis of the obtained results by ICP-OES and ICP-MS revealed that there is no significant difference between the detected concentrations of Al, Zn, Fe, Cu and Cd eighter in the local or imported tea samples in each of the extraction methods. The obtained result showed that the amount of detected Pb in the ICP-MS technique for both internal and imported tea samples is significantly higher than those of ICP-OES technique.

Concentrations of all metal elements in the studied tea samples were significantly higher than of standard reference (NIESNO.7). However, the estimated daily intake of all elements for each adult person is still within the allowable level of the World Health Organization.

Turmeric as the scientific name of Curcuma longa L. belongs to Zingiberaceae family. Extraction method is effective on the percentage and type of chemical compounds present in the extract. The aim of this study was phytochemical surveying of turmeric soxhelt extract by using instrumental analysis and determination of flavonoids and flavenols contents in different extraction methods. Phytochemical tests were done on ethanolic soxhelt extract to determine secondary metabolites and different instrumental analysis methods in order to verify the existence of curcuminoids on it extract took place. The content of flavonoids and flavonol extracts were measured by different extraction methods (maceration, ultrasonic and soxhlet) using quercetin as a standard. The results of phytochemical studies have confirmed the presence of alkaloid, flavonoids and glycosides compounds and the absence of tannins and saponins in the ethanolic soxhelt extract. The results of IR, UV, GC and GC / Mass indicate the presence of curcuminoids in turmeric extract by soxhelt extraction. The results of statistical tests indicated that the highest content of flavonoids and flavenols belongs to the extraction with hexane and ethanol. In soxhelt method despite requiring high temperature and using of hot solvent, the curcuminoids structure was retained and this extraction method may be a suitable method for curcumin extraction from turmeric plant. Also suitable method for extracting flavonoids and flavonoid compounds is extraction with two solvent “ethanol and hexane“.

Medicinal plants of Genus Ferula are prennial herbs of Apiaceae family which are widely distributed all around the word. Many of Feula species are exclusive and endemic to Iran which has widespread uses in traditional medicine as food additive, as well as a carminative, antispasmodic and expectorants. Coumarins, flavonoids and sulfur-containing compounds with different biological effects have been reported from the plant.
The phytochemical investigation on total extract of the aerial parts of Ferula persica Willd var. Latisecta collected from the Central Alborz Protected Area was subjected with the aim of purification and determination of main metabolite constituents of the plant extract.
Dried and powdered plant material was extracted by maceration method. Then the extract was concentrated under reduced pressure to leave a residue which was defatted and chromatographed on a silica gel column by increasing slightly the polarity with solvent. After the serial fractionation the fractions were compared by TLC, and those giving similar coumarin spots were combined and further purified on PLC to give a pure natural compound.
After the purification step the remarkable constituents were obtained. Elucidation of results by spectral methods (IR, 1H-NMR, 13C-NMR and DEPT) demonstrate that a coumarin namely: Auraptene (7-genaryloxycoumarin) was isolated from the aerial parts of F. persica. var. latisecta.
F. persica is an endemic and endangered species of medicinal plants of Iran which contains different natural compounds such as coumarins. So the Protection of the plant for its economic and scientific uses is so important.

Supercritical fluid extraction (SFE) is an alternative to liquid extraction using solvents. Supercritical fluids can have solvating powers similar to organic solvents, but with higher diffusivities, lower viscosity, and lower surface tension. Carbon dioxide is the most commonly used supercritical fluid owing to its nontoxic, nonflammable, inexpensive, environmental friendly properties and mild critical conditions (Tc = 31.1 C and Pc = 73.8 bar). Due to the low heat of process and the relatively unreactive solvent used in the extraction, the fragrant compounds derived often closely resemble the original characteristics of the raw material. Like solvent extraction, extracts a wide range of compounds and leaves the aromatics unaltered by heat, rendering an essence more faithful to the original. In this review, some aspects of this etraction methods have been discussed.

Canola seed is one of the most important oil seed with high ratio of oil and high nutritional value and is economically recommended for cultivation and oil extraction. Extraction with ultrasound waves as a nondestructive and novel method might be employed. Therefore the aim of this research is optimization of extraction of canola oil by ultrasound waves and RSM.
In this project, Response Surface Methodology was employed for optimization of canola oil extraction by ultrasound waves using hexane and hexane/isopropanol as solvents by the ratio of 3:2 (v/v). The influence of extraction temperature in the range of 35, 45 and 55℃, ultrasound treatment time for 30, 60 and 90 minutes and ratio of solvent to canola in three levels of 5, 10 and 15 ml/g were analyzed by Box-Behnken Design (BBD) based on extracted oil percent. The fatty acid compositions of the extracted oils using ultrasound-assisted method and soxhlet method employing gas liquid chromatography were determined and compared.
According to the high values of correlation coefficients of selected models optimized for hexane solvent extraction methods (R2 =0.93) and hexane-isopropanol solvent mixture (R2 =0.97) and no significant lack of fit tests (P>0.05) selected models might be useful to predict the extraction percentage of canola oil.
The results showed that the optimum conditions for canola oil extraction by hexane (22.39 %) and combined hexane/isopropanol (30.66 %) were respectively at ultrasound treatment times of 69.5 and 87 minutes, temperatures of 55 and 55 ℃ and ratio of solvent to canola of 6.39 and 9.12 (%v/w). Extraction efficiency was significantly improved by ultrasound as compared to the soxhlet extraction. Fatty acid compositions of the canola oils were not significantly affected by the application of ultrasound (P> 0.05). Therefore ultrasound might be regarded as a simple and rapid method to improve the extraction of oil without affecting the quality of the fatty acids present.

To reduce the use of organic solvent, Subcritical water extraction has become a popular green extraction technology for production of phytochemicals from a variety of biomasses. Phytochemicals, such as phenolic component, essential oils and carbohydrates, have countless applications in the pharmaceutical, food and other industries.
To review the literature that describes the current status of subcritical water extraction on production of phytochemicals.
This study was based on literature reviews of recent publications in the field of extraction of bioactive compounds by subcritical water.
This article was attempted to give overall view about different features of subcritical water extraction include properties of subcritical water, the application of this solvent to extract the bioactive compounds from different plant materials, the parameters affecting subcritical extraction efficiency (such as temperature, flow rate, extraction mode, matrix composition, pH, pressure, modifiers and additives), the technique to modify the extraction of thermally labile bioactive materials, the studies on kinetics and modelling of subcritical water extraction, water as solvent and anti-solvent, Precipitation techniques and particle formation by subcritical water, future trends and perspectives of upcoming potential applications this technology are reviewed.
Subcritical water extraction is a simple, inexpensive, convenient and environmentally friendly approach and easily coupled with other extraction and purification methods. Further study and development of appropriate models are required to achieve the best operating conditions and Development of Industrial Application of this method.

Collagen is a protein with several applications in the pharmaceutical, cosmetic, medical and food industries that is prepared from different sources such as cow, pig, poultry and fish. In this study, optimization of the extraction of collagen from eggshell membrane was examined.
The efficiency of extraction of collagen in different concentrations of sodium hydroxide (2/0-2 /1 N) at different treatment times periods (6-36 hours), different concentrations of pepsin (U/mg90-15) and enzymatic hydrolysis times (6-60 hours) was studied with response surface methodology (RSM). Also the properties of eggshell membrane collagen were characterized by amino acid analyzer, SDS- PAGE and solubility.
The most important factors for extraction of collagen using RSM according to central composite design were optimized. Optimum extraction conditions were as follows: NaOH concentration of 0.76 N, alkali treatment time of 18 h, enzyme concentration of 50 U/mg and hydrolysis time of 43.42 h. The experimental extraction yield under optimal conditions was found to be 30.049%. Collagen solubility in pH=3 and NaCl concentration of less than 2% was determined. The analysis showed that Glycine having 322/1000 amino acids as the most amino acids and the immune-acid (sum of Proline and hydroxylproline) of collagen was 19.5 %. SDS- PAGE protein pattern revealed two different a (α1 and α2) components with β and γ chains.
Collagen was extracted from eggshell membrane with optimum extraction efficiency, which can be used in film production, gelatin and functional food components to maintain health and control chronic diseases.

Saffron with the botanical name of Crocus sativus L., is the most expensive spice in the world. Introduction of a suitable method for the extraction of these bioactive compounds, as well as the technological and economical issues are important points to be considered. The aim of this study is to develop the most economical method to extract the bioactive compounds of saffron.
In the present study the extraction conditions of crocin, safranal and picrocrocin in the binary solvent system (water: ethanol and water: acetone) as well as ternary solvent system (water: acetone : ethanol) were investigated in terms of different ratios of solvents and different ratios of solvent to saffron.
The best extraction conditions were found with the binary solvent system of ethanol: water; 3:2 with a solvent ratio of 12 ml per gram of saffron and also applying the ternary solvent system of water: acetone: ethanol (40:45:15) per gram of saffron at 25° C for 16 hours to extract the optimal saffron bioactive compounds. The amount of crocin, safranal and picrocrocin in the aqueous extract of saffron were measured 229.05, 35.17 and 75.53 respectively for the binary solvent system of ethanol: water and 272.96, 40.03 and 13.6 respectively for the ternary solvent system of water: acetone: ethanol (40:45:15).
Based on the need for the desired color and flavor in various food processing, and considering the economical aspects, each of the proposed extraction method might be used.

Tarragon (Artemisia dracunculus L.) has been utilized as a spice for many years. The essential oil of Tarragon can be used as a natural food preservative since the plant has antioxidant and antimicrobial properties. There has been a variety of methods to extract essential oils. Different methods of extraction might affect extraction rate, percentage and chemical composition amounts of the extracted essential oils.
To find the best method of essential oil extraction, comparing different methods can be performed. In this research two methods of extraction have been compared.
Essential oil of Tarragon was obtained by hydrodistillation and solvent free microwave extraction. Oils were analyzed and the components were identified using gas chromatography-mass spectrometry.
The major components of the oil extracted by hydrodistillation were estragol (29.05%) and limonene (11.87%). Estragol (62.40%) and thymol (9.25%) were the major components isolated by microwave free solvent.
Considering temperature and time of extraction, different extraction methods make noticeable changes in chemical composition of the oils.

Bakhtiari savory (Satureja bachtiarica Bunge.) has a high anti-oxidant ability. Kinds of extraction methods are effective on the kind and percent of existence chemical compounds in herbal essences. The aim of this study was to compare antioxidant activities from Satureja bachtiarica Bunge essential oils extracted from different extraction methods to determine the extraction optimization.
Antioxidant activities and the rate of phenol in the essential oils of Bakhtiari savory was extracted by eight different methods in two models, Conventional hydrodistillation ( single distillation, distillation with steam, and distillation with water and steam), and innovative techniques (water penetration method by microwave-assisted and microwave-assisted with water) in DPPH and in DPPH and Folin ciu Calteu method. In this study, BHT and Ascorbic acid were applied as positive control. Data were analyzed using analytic statistical tests and SPSS software.
The statistical tests results showed a significant difference in phenol content, and IC50 of obtained essences in different extraction methods (P The steam and microwave– assisted extraction techniques were the best extraction methods with high protective antioxidant activity.