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1.
Braz. J. Pharm. Sci. (Online) ; 58: e20577, 2022. graf
Article in English | LILACS | ID: biblio-1403738

ABSTRACT

Abstract Lysiphyllum strychnifolium (Craib) A. Schmitz. (in Thai name, Ya nang daeng) has been traditionally used to treat fever, alcohol intoxication, cancer, allergies, and blood toxins. It can be used as a health-promoting herbal tea and contains hydroalcoholic extracts. The purpose of the present study was to develop a microwave-assisted extraction method for astilbin in L. strychnifolium stems. HPLC was used to determine astilbin content. Three extraction conditions were optimized: types of solvent, microwave power levels, and the number of extraction cycles. Water:methanol (40:60) was the best solvent for astilbin extraction from L. strychnifolium stems using 450 watts and six microwave-assisted extraction cycles. This technique offers important advantages over conventional methods, such as shorter extraction times, substantial energy savings, and a reduced environmental burden.


Subject(s)
Plant Stems/classification , Fabaceae/classification , Microwaves/adverse effects , Chromatography, High Pressure Liquid/methods
2.
Journal of Preventive Medicine ; (12): 101-105, 2022.
Article in Chinese | WPRIM | ID: wpr-907092

ABSTRACT

Objective @#To establish a microwave-assisted digestion-inductively coupled plasma mass spectrometry (ICP-MS) with an octopole reaction system for simultaneous determination of six heavy metals in peanuts, including Cr, Ni, As, Cd, Pb, Hg. @*Methods @#Peanut samples were shelled and crushed evenly, and 0.350 0 g was accurately weighed and digested with 5 mL nitric acid and 1 mL hydrogen peroxide in a digestion tank. Following microwave-assisted digestion, pure water was used to quantify the samples, and internal standards and an octopole reaction system were used to remove the interference. Then, the contents of six heavy metals were determined in peanuts by ICP-MS. The accuracy and precision of ICP-MS were evaluated using national criteria ( GBW 10013 and GBW 10044 ) and spike-and-recovery testing. @*Results @#The six heavy metals showed good linearity at the selected linear range ( r≥0.999 8 ). The detection limits of ICP-MS ranged from 0.001 4 to 0.023 8 ng/mL, and the spike-and-recovery rates ranged from 94.7% to 98.8%, with the relative standard deviations ranging from 0.7% to 3.6%. In addition, the determination results of the standard reference materials were all within the normal reference range. The detection of six heavy metals was 100.0% in 60 peanut samples, and the contents of six heavy metals were all low.@*Conclusion @#The established ICP-MS assay is feasible for simultaneous determination of multiple heavy metals in peanuts.

3.
Rev. chil. nutr ; 47(6)dic. 2020.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1388448

ABSTRACT

RESUMEN La extracción asistida por microondas (MAE por sus siglas en inglés) es una técnica eco amigable relativamente nueva que ha recibido una atención creciente debido a su menor tiempo de extracción y consumo de energía, mayor rendimiento de compuestos de interés y menor consumo de disolvente; a diferencia de técnicas convencionales de extracción, que implican elevados gastos de energía y tiempo. Así mismo, subproductos de industrias como cáscaras de cítricos, son desechados en grandes cantidades, no aprovechándose las propiedades funcionales sus compuestos. En esta investigación se realizó la extracción de aceite esencial a partir de cáscara de naranja, por microondas libre de solventes (SFME por sus siglas en inglés), a diferentes condiciones de potencia (400, 800 W, y sus combinaciones). El objetivo fue evaluar el efecto de las diferentes condiciones de proceso sobre el rendimiento del aceite esencial extraído, sobre su composición química y actividad antimicrobiana. Los más altos rendimientos de extracción correspondieron a los aceites extraídos a 400 W y a 800/400 W, siendo este último el que conllevó un menor gasto de energía y emisión de CO2. En general, todos los aceites extraídos presentaron los mismos compuestos mayoritarios (limoneno, β- mirceno, linalool y α- pineno), mientras que el aceite sometido a 400 W, presentó cantidades menores de 0,23% de 5 compuestos minoritarios adicionales. Sobre la actividad antimicrobiana, se detectó mayor actividad contra Listeria monocytogenes (ATCC 19115) respecto a Escherichia coli (ATCC 8739) en todos los tratamientos.


ABSTRACT Microwave assisted extraction (MAE) is a relatively new ecofriendly technique that has received increasing attention due to its reduced extraction time and energy consumption, higher yield and lower solvent consumption; unlike conventional extraction techniques, which involve higher energy costs and greater time. Likewise, industry by-products such as citrus peels are disposed of in large quantities, thus functional properties of their compounds are left unused. In the present investigation, solvent-free microwave extraction (SFME) was used to obtain orange peel essential oil at different power conditions (400, 800 W, and their combinations). The aim was to evaluate the effect of the process on the yield, composition and antimicrobial activity of the essential oil obtained. The highest extraction yields were obtained using powers of 400 and 800/400 W, corresponding the minor energy and CO2 emission generated to the latter. In general, all oils had the same major components (limonene, β- myrcene, linalool and α- pinene), with the oil obtained at 400 W having, in addition, five minor compounds, in amounts less than 0.23%. Regarding antimicrobial activity, in general, greater activity against L. monocytogenes (ATCC 19115) was detected in comparison with E. coli (ATCC 8739) in all treatments.

4.
Article | IMSEAR | ID: sea-210720

ABSTRACT

Green grass jelly (Cyclea barbata Miers.) is a plant from Indonesia that is believed to have anti-inflammatory activity.This study aims to find the optimum condition in grass jelly extraction using the ionic liquid-microwave assistedextraction toward total flavonoid content (TFC) and lipoxygenase activity (LIA). The experimental design wasperformed using the parameters variable including extraction time, liquid–solid ratio, and ionic liquids concentrationto obtain the optimum condition. The optimization analysis used response surface methodology (RSM) with Box–Behnken design (17 trials) to obtain a predictive model with TFC and LIA as a response surface value. In the presentstudy, the optimum condition was suggested by RSM analysis with parameter variables, including extraction time of17 minutes, 1-butyl-3-methylimidazolium bromide ([BMIM]Br) concentration of 1.76 mol/l, and the liquid–solid ratioof 38.21 ml/g. The equation of regression quadratic model was obtained to predict TFC and LIA as follows: TFC =2.43A + 2.43B + 1.42C + 0.33AB − 3.20AC − 0.46BC − 4.90A2 − 3.10B2 − 3.10C2 + 28.32 with R2 = 0.8336 and LIA= 0.066A + 8.22B + 0.97C + 2.47AB − 5.86AC + 1.96BC − 9.99A2 − 13.75B2 − 13.11C2 + 63.53 with R2 = 0.9207,respectively

5.
Article | IMSEAR | ID: sea-210711

ABSTRACT

Oxyresveratrol is a polyphenolic compound found in Mulberry (Morus alba L.) twigs and has known as a skinlightening agent. Many methods can be applied to extract oxyresveratrol from Mulberry twigs. This researchaimed to optimize the extraction method by using surfactant Tween 80 and Tween 20-based microwave-assistedextraction (MAE). Extraction parameters, including solvent concentration, liquid–solid ratio, and extraction time foroxyresveratrol, were optimized using response surface methodology based on Box–Behnken Design. This researchalso extracted the oxyresveratrol by maceration, and then the oxyresveratrol content from each extraction methodwas compared. Oxyresveratrol content was determined using high-performance liquid chromatography (HPLC). ForTween 80, the optimum condition was obtained at 10.5 mM, 30:1 ml/g liquid–solid ratio, and 10 minutes extractiontime. For Tween 20, the optimum condition was obtained at 100 mM, 40:1 ml/g liquid–solid ratio, and 5 minutesextraction time. Oxyresveratrol content was 0.0146 mg/g dried sample and 0.0172 mg/g dried sample at the optimumcondition of Tween 80 and Tween 20 surfactant, respectively. Meanwhile, the oxyresveratrol content of the macerationmethod with 96% ethanol was 1.5704 mg/g dried sample. In conclusion, these results show that the application ofTween 80 and Tween 20 as solvents for MAE of Oxyresveratrol from mulberry twigs was not fully successful sinceother extraction conditions should be considered, such as temperature, pH, and microwave energy.

6.
Braz. J. Pharm. Sci. (Online) ; 56: e18111, 2020. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1089215

ABSTRACT

In this study, twenty-two new [1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles (5a-n, 6a-h) were synthesized under microwave irradiation (MWI). The chemical structures of the compounds were elucidated by their IR, 1H-NMR, LC-MS, and elemental analysis. The compounds were tested for antinociceptive activity by using the tail clip, tail flick, hot plate, and writhing methods in mice. The varying levels of antinociceptive activity of the compounds were compared with those of aspirin. Among these compounds, compound 5g and 5j were found to be significantly more active than the other compounds and the standard in the tests. Also, inhibitory effects of the test compounds on COX-1 and COX-2 activities were investigated. DuP-697 for COX-2 and SC-560 for COX-1 were used as reference standards.

7.
Article | IMSEAR | ID: sea-210431

ABSTRACT

Modern extraction technique was investigated for the separation of betulinic acid from the bark of Dillenia indicaLinn. Betulinic acid, a pentacyclic triterpenoid, is a potent anticancer compound and possesses other pharmacologicalactions. The objective of the present study was to investigate the optimum extraction conditions for betulinic acidusing microwave-assisted extraction by applying response surface methodology based on three factors three levelsBox–Behnken experimental design. The extraction was performed by considering three different independent variables:extraction temperature (70°C–90°C), microwave power (100 W), and extraction time (10–20 minutes) and quantifiedusing developed High-performance thin layer chromatography method. The maximum yield of betulinic acid at optimizedexperimental conditions, i.e., 90°C, 200 W, 15 minutes was found to be 0.91%w/w. Analysis of variance showed that the“p-value” was 0.0004 which indicate that the models were statistically significant (p ˂ 0.05). The value of the “coefficientof determination” (R2) for microwave-assisted extraction was 0.94 which indicate that the model shows the goodness offit. To conclude, Microwave Extraction technique along with response surface design proved to be efficient compared toconventional methods which could be applied to isolate active constituents from plant sources.

8.
Chinese Traditional and Herbal Drugs ; (24): 3691-3699, 2019.
Article in Chinese | WPRIM | ID: wpr-850965

ABSTRACT

Flavonoids are widely found in medicinal plants, which have important medical properties. Flavonoids were proved to have many pharmacological activities, such as anti-oxidation, antitumor, antimutation, anti-inflammatory, antibacterial and anti-aging. The extraction of flavonoids is the crucial link in their clinical applications. In recent years, many emerging Chinese medicine extraction methods have also been widely used in the extraction of flavonoids. This paper reviews the current application of new methods for flavonoid extraction, in order to provide references for the extraction, development and utilization of flavonoids. These new extraction methods include supercritical fluid extraction (SFE), ultrasonic assisted extraction (UAE), microwave assisted extraction (MAE), pressurized liquid extraction (PLE), pulsed electric field (PEF) assisted extraction, enzyme assisted extraction (EAE), green solvent extraction, steam explosion assisted extraction, dynamic high pressure microfluidization (DHPM) assisted extraction, etc.

9.
Journal of Pharmaceutical Analysis ; (6): 209-216, 2019.
Article in Chinese | WPRIM | ID: wpr-753365

ABSTRACT

In this work, lemon and onion biomasses commonly found in street markets are for the first time used to develop a facile, fast and low-cost one-step microwave-assisted carbonization method for synthesis of highly fluorescent carbon dots (CDs). The structure and optical properties of CDs were investigated by TEM, XRD, XRF, UV-Vis, FTIR, and fluorescence spectroscopy. CDs displayed satisfactory optical pro-prieties, a high quantum yield of 23.6%, and excellent water solubility, and the particle size was 4.23-8.22 nm with an average diameter of 6.15 nm. An efficient fluorescent resonance energy transfer (FRET) between the CDs and riboflavin was achieved with CDs acting as donor and riboflavin as acceptor. A linear relationship between FRET and the riboflavin concentration from 0.10 to 3.0 μg/mL was observed, allowing the development of an accurate and fast analytical method to determine this vitamin in multivitamin/mineral supplements. Despite the potential interferences in these supplements, CDs were selective for riboflavin under optimized conditions. A paired t-test at a 95% confidence level indicated no statistically significant difference between the proposed and the reference methods. Recovery test presented values ranged from 96.0% to 101.4%. The limit of detection and relative standard deviation were estimated at 1.0 ng/mL and <2.6% (n = 3), respectively. CDs were successfully synthesized in a domestic microwave oven (1450 W, 6 min), presenting satisfactory parameters when compared with results of other studies reported in the literature, suggesting that the proposed method is a potentially useful method for the synthesis of CDs and determination of riboflavin.

10.
Food Sci. Technol (SBCTA, Impr.) ; 38(1): 157-163, Jan.-Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-892250

ABSTRACT

Abstract A 32 factorial design was employed to develop an in vitro digestion method for estimation of Fe bioaccessible fractions in cooked chicken meat. The effects of sample size and the in vitro bioaccessible fractions of this essential element were evaluated. A sample preparation method employing a microwave assisted digestion with dilute nitric acid was used prior to total Fe determination. For the bioacessibility studies, the optimized procedure employed 7.5 g of sample and 6% w/v of an acid pepsin solution. This procedure was applied to two kinds of chicken meat samples: breast and liver. Flame Atomic Absorption Spectrometry was used to determine total and bioaccessible (chyme or soluble portion) levels of iron in the samples. With respect to total Fe content, the bioaccessible fractions of Fe found in these samples were around 23% and 56 %, for breast and chicken liver, respectively. The chicken liver sample showed the highest total (400 ± 10 mg kg-1) and bioaccessible Fe contents (223 ± 18 mg kg-1) and stands out as a good source of this micronutrient.

11.
Natural Product Sciences ; : 75-83, 2017.
Article in English | WPRIM | ID: wpr-216625

ABSTRACT

The optimization and microwave assisted extraction of stem bark of Terminalia arjuna, quantitative estimation of the marker compounds arjunic acid and arjunolic acid using HPTLC and the evaluation of free radical scavenging activity has been performed in this study. The central composite design was used for optimization and the values of parameters for optimized batch of microwave assisted extraction were 1000W (Power), 3 minutes (Time) and 1/120 (Solid/solvent ratio). The solvent system to carry out the HPTLC was toluene: acetic acid: ethyl acetate (5: 5: 0.5) and quantitative estimation was done using standard equations obtained from the marker compounds. The in-vitro free radical scavenging activity was performed spectrophotometrically using ascorbic acid as standard. The value of estimated percentage yield of arjunic acid and arjunolic acid was 1.42% and 1.52% which upon experimentation was obtained as 1.38% and 1.51% respectively. The DPPH assay of the different batches of microwave assisted extraction and marker compounds taken suggested that the marker compounds arjunic acid and the arjunolic acid were responsible for the free radical scavenging activity as the batch having the maximum percentage yield of the marker compounds showed best free radical scavenging effect as compared to standard ascorbic acid. The IC₅₀ value of the optimized batch was found to be 24.72 while that of the standard ascorbic acid was 29.83. Hence, the yield of arjunic acid and arjunolic acid has direct correlation with the free radical scavenging activity of stem bark extract of Terminalia arjuna and have potential to serve as active lead compounds for free radical scavenging activity.


Subject(s)
Acetic Acid , Ascorbic Acid , Microwaves , Terminalia , Toluene
12.
Chinese Journal of Analytical Chemistry ; (12): 1467-1474, 2017.
Article in Chinese | WPRIM | ID: wpr-658504

ABSTRACT

As a kind of fluorescent nanoprobe, BHHCT-Eu3+ @ SiO2 fluorescent nanoparticles were synthesized using microwave irradiation. Transmission electron microscopy characterization showed that the nanoparticles were in spherical shape with particle size of about 36 nm. The BHHCT-Eu3+@SiO2 exhibited good fluorescence property, with a maximal excitation wavelength of 343 nm and an maximal emission wavelength of 615 nm. The fluorescence lateral flow immunoassay ( LFIA ) was established for rapid and quantitative detection of kanamycin ( Kana) in milk after BHHCT-Eu3+@SiO2 fluorescent nanoparticles were conjugated with Kana antibody, with dextran as a linker. The limit of detection of Kana with the LFIA method was 0. 85 ng/mL with IC50 of 12. 76 ng/mL, and the detection range was from 3. 0 ng/m to 76 ng/mL. The recoveries of Kana in milk were between 93 . 7% and 97 . 4% with RSD of 3 . 1%-4 . 6%, and cross-reactivity of the fluorescence immunoassay strip for Kana determination was<1%. The detection results of kana in milk samples between the LFIA and traditional ELISA method showed good correlation.

13.
Chinese Journal of Analytical Chemistry ; (12): 1467-1474, 2017.
Article in Chinese | WPRIM | ID: wpr-661423

ABSTRACT

As a kind of fluorescent nanoprobe, BHHCT-Eu3+ @ SiO2 fluorescent nanoparticles were synthesized using microwave irradiation. Transmission electron microscopy characterization showed that the nanoparticles were in spherical shape with particle size of about 36 nm. The BHHCT-Eu3+@SiO2 exhibited good fluorescence property, with a maximal excitation wavelength of 343 nm and an maximal emission wavelength of 615 nm. The fluorescence lateral flow immunoassay ( LFIA ) was established for rapid and quantitative detection of kanamycin ( Kana) in milk after BHHCT-Eu3+@SiO2 fluorescent nanoparticles were conjugated with Kana antibody, with dextran as a linker. The limit of detection of Kana with the LFIA method was 0. 85 ng/mL with IC50 of 12. 76 ng/mL, and the detection range was from 3. 0 ng/m to 76 ng/mL. The recoveries of Kana in milk were between 93 . 7% and 97 . 4% with RSD of 3 . 1%-4 . 6%, and cross-reactivity of the fluorescence immunoassay strip for Kana determination was<1%. The detection results of kana in milk samples between the LFIA and traditional ELISA method showed good correlation.

14.
Rev. cuba. plantas med ; 21(1)jan.-mar. 2016. ilus, tab
Article in Spanish | LILACS | ID: lil-781971

ABSTRACT

Introducción: Phaseolus vulgaris L. (frijol) es una fuente nutricional importante en Colombia, que aporta un gran contenido de sustancias bioactivas con potencial benéfico para la salud, tales como polifenoles, entre otras, que contribuyen de manera sinérgica con sus propiedades terapéuticas, y que pueden tener un efecto positivo contra algunas patologías. Objetivos: evaluar el método de extracción asistido por microondas como método alternativo para estudiar la capacidad antioxidante in vitro en ocho variedades de P. vulgaris L. cultivadas en Colombia. Métodos: semillas sin piel de P. vulgaris, deshidratadas y maceradas se sometieron a extracción asistida por microondas y extracción sólido-líquido; el contenido de fenoles se evaluó por el método de Folin-Ciocalteu y el potencial antioxidante in vitro se evaluó con base en los métodos del radical estable catión radical difenil-picrilhidrazilo y el radical catión 2,2´-azino-bis(ácido 3-etilbenzotiazolin-6-sulfunico). Resultados: el método de extracción asistido por microondas realizada en horno microondas convencional fue más eficiente respecto a la convencional ya que disminuyó la cantidad de solvente, de muestra empleada y los tiempos de extracción. Los extractos obtenidos por extracción asistida por microondas en horno microndas convencional presentaron un contenido de fenoles entre 29,36 y 60,61 g EAG/L, mientras que el método extracción sólido-líquido, estuvo entre 32,75 y 113,27 g EAG/L. El efecto anti-radicalario fue similar entre los extractos evaluados. Conclusiones: todos los extractos presentaron buena capacidad protectora contra radicales libres, y la técnica de extracción asistida por microondas en horno microndas convencional puede ser usada como método alterno para una valoración rápida, eficiente y eficaz del contenido de sustancias bioactivas en diferentes matrices, se presentó mínimas diferencias entre los resultados obtenidos, comparados con las metodologías de extracción asistida por microondas establecidas antes(AU)


Introduction: Phaseolus vulgaris L. is a representative crop of nutrient and economic importance in Colombia. Additionally, P. vulgaris is considered as a natural source of bioactives compounds, such as polyphenols, which have been associated with valuable effects on health. Objetives: to evaluate the microwave extraction assisted technique as an alternative methodology to study the antioxidant capacity of eight varieties of P. vulgaris cultivated in Colombia. Methods: dehydrated and powered seeds of P. vulgaris was subjected to microwave assisted extraction and solid-liquid extraction and. Total phenolis content was determined by Folin-Cicoulteau method and the potential antioxidant was evaluated using diphenyl-picrylhydrazyl radical stable and 2,2-Azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation assays. Results: microwave assisted extraction-Household microwave oven technique was more efficient and versatile than SLE method. The extracts obtained microwave assisted extraction-Household microwave oven methodology showed polyphenol content ranged between entre 29,36 and 60,61 g EGA/L, but SLE was over 32,75 and 113,27 g EAG/L. Conclusions: all extracts showed a considerable antioxidant potential against free radical, and microwave assisted extraction-Household microwave oven method could be used as an alternative method for fast, efficient and effective evaluation of the content of polyphenol in various matrices, with minimal differences comparing to established microwave assisted extraction techniques(AU)


Subject(s)
Humans , Phytohemagglutinins/chemistry , Chromatography/methods , Antioxidants/therapeutic use , Colombia
15.
Rev. colomb. ciencias quim. farm ; 45(1): 109-126, ene.-abr. 2016. ilus, tab
Article in Spanish | LILACS | ID: lil-791294

ABSTRACT

En este trabajo se muestra el desarrollo y la validación de un método analítico para la cuantificación de polifenoles totales con el reactivo de Folin-Ciocalteu (F-C),en procesos de extracción asistida por microondas (MAE), sobre frutos de la especie colombiana Vaccinium meridionale. Los resultados obtenidos en los parámetros selectividad, linealidad, repetibilidad y exactitud muestran que la metodología propuesta es confiable para evaluar el efecto de las condiciones de extracción sobre la cantidad de polifenoles removidos.


In this work, we show the development and validation of an analytical method for quantification of total polyphenols with Folin-Ciocalteu reagent (F-C) in microwave-assisted extraction processes for Colombian species Vaccinium meridionale. Experimental results of selectivity, linearity, repeatability and accuracy evidence that the methodology proposed is reliable to evaluate the effect of the extraction conditions over the quantity of polyphenols removed.

16.
Herald of Medicine ; (12): 761-764, 2016.
Article in Chinese | WPRIM | ID: wpr-492959

ABSTRACT

Objective To research the microwave-assisted extraction of polysaccharides from Glechoma longituba. Methods In present study, the processes of extraction of polysaccharides from Glechoma longituba by water bath and microwave-assisted extraction were optimized using orthogonal test, and the two methods were compared. Results The optimal process of water bath extraction was as follows:liquid-solid ratio 50∶1, time 180 min, temperature 90 ℃ and pH 8. 0. The optimal parameters of microwave-assisted extraction were liquid-solid ratio 30∶1, top microwave power, time 4 min, and pH 8.0. The yield of polysaccharides from Glechoma longituba by microwave-assisted and water bath methods was (4.58±0.09)% and (3.09±0.12)%, respectively, and the yield of microwave-assisted method was elevated by 48.2% compared with that of water bath extraction. Conclusion The microwave-assisted extraction of polysaccharides from Glechoma longituba not only improves the yield, but also reduces the extract volume, saves energy and time.

17.
Journal of Pharmaceutical Analysis ; (6): 382-388, 2016.
Article in Chinese | WPRIM | ID: wpr-506455

ABSTRACT

In this work, a fast and efficient microwave-assisted extraction (MAE) method was developed to extract main bioactive alkaloids from lotus plumue. To optimize MAE conditions, three main factors were selected using univariate approach experiments, and then central composite design (CCD). The optimal extraction conditions were as follows: methanol concentration of 65%, microwave power of 200 W, and extraction time of 260 s. A high performance liquid chromatography–diode array detector (HPLC–DAD) method was established to quantitatively analyze these phytochemicals in different lotus plumule samples and in different part of lotus. Chromatographic separation was carried out on an Agilent Zorbax Extend-C18 column (4.6 mm×150 mm, 3.5 μm). Gradient elution was applied with the mobile phase constituted with 0.1%triethylamine in water (A) and acetonitrile (B): 40%?70% B at 0?8 min, 70%?100% B at 8–9 min, 100% B for 2 min, and then equilibrated with 40%B for 2 min.

18.
Asian Pacific Journal of Tropical Medicine ; (12): S204-11, 2014.
Article in English | WPRIM | ID: wpr-820611

ABSTRACT

OBJECTIVE@#To investigate the effect of seed extracts of Pongamia pinnata, Pyrus pyrifolia, and Manilkara hexandra, bacterial pigment prodigiosin, and three organic solvents (ethanol, methanol, and dimethylsulfoxide), on quorum sensing (QS) in Chromobacterium violaceum (C. violaceum).@*METHODS@#C. violaceum was challenged with plant extracts prepared by microwave assisted extraction method, prodigiosin, and organic solvents. Effect of these test substances on C. violaceum growth, and quorum sensing regulated pigment (violacein) production was studied by broth dilution assay. High performance liquid chromatography was also applied to generate chromatographic fingerprint of the active extracts. Effect of sub-minimum inhibitory concentration level of the antibiotic streptomycin on quorum sensing regulated pigment production was also studied.@*RESULTS@#Pongamia pinnata seed extracts and prodigiosin were found to possess anti-QS, and Manilkara hexandra and Pyrus pyrifolia seed extracts to possess QS-enhancing effect in C. violaceum. Dimethylsulfoxide was found to enhance violacein production, whereas ethanol and methanol reduced violacein production in C. violaceum. Streptomycin at sub-minimum inhibitory concentration level was able to significantly arrest QS-regulated pigment production in C. violaceum and Serratia marcescens.@*CONCLUSIONS@#Prodigiosin and the seed extracts used in this study could affect quorum sensing in C. violaceum to a notable extent. Results of this study also emphasize the importance of inclusion of appropriate solvent controls (negative controls) in bioassays designed for screening of antimicrobial and/or anti-QS compounds. Antipathogenic potential of low concentrations of streptomycin was also demonstrated.

19.
Chinese Pharmaceutical Journal ; (24): 664-668, 2014.
Article in Chinese | WPRIM | ID: wpr-859762

ABSTRACT

OBJECTIVE: To prepare heme from cherry valley duck blood. METHODS: Single factor experiments and orthogonal experiment were carried out to establish the optimal process of preparing heme from cherry valley duck blood by a new microwave-assisted acid acetone extraction method. RESULTS: Single factor experiments proved that the microwave-assisted extraction process significantly improved the extraction efficiency of heme. In addition, orthogonal experiment indicated the power of microwave and microwave extraction time had significant effects on the extraction results, and the optimum conditions of microwave-assisted extraction in laboratory were as follows: the power was 800 W, extraction time was 60 min, and the temperature was 50°C. CONCLUSION: The new microwave-assisted method, combining cell disruption and heme extraction process, can simplify the traditional acid acetone extraction process, and it is proved to be feasible.

20.
Asian Pacific Journal of Tropical Medicine ; (12): 136-140, 2014.
Article in English | WPRIM | ID: wpr-819717

ABSTRACT

OBJECTIVE@#To prepare a novel biodegradable poly(2-hydroxyethylmethacrilate) (pHEMA) hydrogel as tissue engineering scaffold.@*METHODS@#The pHEMA hydrogel was synthesized by microwave-assisted polymerization using 2-hydroxyethyl methacrylate (HEMA) as the raw material, potassium persulfate as the initiator, and PCLX as the cross-linking additive. The hydrogels was characterized with FTIR and NMR spectroscopy. The physical and chemical properties of the prepared hydrogel were evaluated, and its degradation performance was tested. The cytotoxicity of the optimum composite hydrogel was measured by an MTT assay to confirm the feasibility of its use in tissue engineering.@*RESULTS@#The optimum conditions under which the hydrogel was prepared by microwave-assisted polymerization are as follows: 1.5 g cross-linking additive, 0.3 g initiator, reaction temperature of 80 °C, and microwave power of 800 W. Degradation studies showed good degradation profiles with 75% in 17 days. Additionally, the hydrogels did not elicit any cytotoxic response in in vitro cytotoxic assays.@*CONCLUSION@#A biodegradable pHEMA hydrogel was successfully prepared by microwave-assisted polymerization, as confirmed from FTIR and NMR results. The hydrogel shows promising applications in tissue engineering, and its healing ability and biocompatibility will be evaluated in detail in the future.


Subject(s)
Animals , Mice , Cell Line, Tumor , Cell Survival , Hydrogel, Polyethylene Glycol Dimethacrylate , Chemistry , Toxicity , Microwaves , Polyhydroxyethyl Methacrylate , Chemistry , Toxicity , Polymerization , Tissue Engineering , Tissue Scaffolds , Chemistry
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