15 research outputs found
Study of hydrolysis and production of instant ginger (Zingiber officinale) tea
The aim of this study is to determine the suitable conditions for enzyme-assisted hydrolysis and the production of instant tea from hydrolysed ginger. Several parameters of ginger hydrolysis were investigated, such as the enzyme concentration from 0.1 to 0.4 g/100 g ginger powder (w/w), material/water ratios of 1/10; 1/15; 1/20; and 1/25 (w/w), pH from 3.5 to 5.0; temperature of hydrolysis process from 45 to 60°C, and time of hydrolysis process from 90 to 150 min. Subsequently, the hydrolysed ginger was spray-dried to produce instant products with surveyed parameters, including the maltodextrin concentration from 15 to 35 g/100 g ginger extraction, feed flow rates from 120 to 600 mL/h, and the temperatures of spray drying from 120 to 150°C. The suitable parameters for enzyme-assisted hydrolysis and production of instant tea were determined, including enzyme concentration as 0.2 g/100 g ginger powder (w/w), material/water ratio as 1/10 (w/w), pH at 5.0, temperature process as 55°C, the time of hydrolysis process as 120 min, the maltodextrin concentration as 15 g/100 g extraction (w/w), feed flow rate as 240 mL h−1, and the inlet temperature as 140°C. Furthermore, the physicochemical properties of the product were identified with moisture content as 2.36 ± 0.09%, total phenolic content as 98.34 ± 0.59 mg gallic acid equivalent/g DW, and IC50 value as 1,082 µgAA/mL
A simple synthesis route for preparation and optical properties of PMMA-g-ZnO nanocomposites through surface-initiated radical polymerization
An effortless chemisorption access for the planning of nanocomposites containing a semiconductor ZnO nanoparticles and poly(methyl methacrylate) (PMMA) is demonstrated. First, thiol-functionalized ZnO (ZnO-SH) were prepared by a silanization reaction between ZnO nanoparticles and (3-mercaptopropyl) trimethoxysilane. Then, a reserved radical polymerization of methyl methacrylate in the attendance of Zinc oxide-thiol (ZnO-SH) and butyrolactam produced PMMA-g-ZnO nanocomposites. DSC were used to examine the weight decline of glass transition temperature of nanocomposites. The ocular characteristics of the nanocomposites were studied by Ultraviolet-visible (UV–vis) absorption spectroscopy and photoluminescence spectroscopy (PL). The results accentuate the role of the grafted PMMA polymer segments in augmenting the strength of dispersal and near-band edge (NBE) emission of ZnO nanoparticles
Research on lemongrass oil extraction technology: hydrodistillation, steam istillation, and microwave-assisted hydrodistillation
Nowaday, people's health issues are of particular interest and motivate them to focus on natural products from countless herbs and plants. Essential oil is one of the most remarkable natural substances. There are hundreds of essential oils and they contain a lot of aromatic compounds [1]. These aromatic compounds are widely used in many products in food, pharmaceuticals and cosmetics. Inside, Lemongrass (Cymbopogon citratus stapf) oil with mainly citral (neral and geranial) component has been considered an important component in the antibacterial, antifungal, antioxidant, antiseptic activities [2]
Green technology to optimize the extraction process of turmeric (Curcuma longa L.) oils
Turmeric oil has many uses in the field of medicine and food. There are many methods of extracting essential oils from plants. However, every traditional method has limitation regarding the heat transfer, time or quality of the oil obtained. In this study, the combination of microwave extraction and response surface methodology are used to extract turmeric oil and optimize the factors that influence the extraction process. The results showed that optimal influencing factors such as the ratio of water to the raw materials were 2.99:1 (mL/g), the microwave power used at 456.60 (W) for the extraction time was 102.43 (min) for the essential oil yield of 0.95 (%) with 100 % reliability
Research on Lemongrass Oil Extraction Technology (Hydrodistillation, Microwave-Assisted Hydrodistillation)
Microwave-assisted hydro-distillation (MAHD) is preferred to traditional extraction methods due to shorter extraction time, the inability of volatile components to be damaged or decomposed which in turn improve the efficiency and quality of essential oils. In this research, we investigated the parameters that affect the extraction of lemongrass oil process by MAHD method and compare with those of hydro-distillation (HD) method. Four parameters were identified which are: raw material size, raw material to water ratio, extraction time and microwave power. The results show that the optimum condition for determining the lemongrass essential oil content is 20 mm in the 90 min extraction time with a microwave power of 450 W at raw material to water ratio of 1:3 (g/mL). When compared to the HD method, we found that the yield lemongrass oil of MAHD method is 0.35% on 90 min and the yield of HD method is 0.2% on 360 min. The quality of oil samples at different extraction method was evaluated by determining their chemical constituents through GC-MS. The highest identified component is Citral with 93.28% for MAHD, while the HD was 83.85%. Therefore, MAHD method is highly efficient and shorten the time needed for the extraction of essential oils
Extraction process of essential oil from plectranthus amboinicus using microwave-assisted hydrodistillation and evaluation of it’s antibacterial activity
Plectranthus amboinicus oil has many applications in pharmaceutical, medicine and cosmetic industries. Recently, new methods of extracting essential oil used have been increasingly developed to replace traditional methods. In this study, maximization of essential oils yield from P. amboinicus was studied by the combination of microwave assisted hydro-distillation (MAHD) and response surface methodology (RSM). We found that that the maximum essential oil yield was 0.1374 % with 94.38 % reliability and influencing factors such as microwave power for this process was 515 W, raw material to water ratio 1.64:1, extraction time at 100.8 min. ANOVA analysis for quadratic model also gives favourable outcome including the high determination coefficient (R2 = 0.94), significant F-value and p-value of coefficients. Under laboratory condition, the obtained yield (0.1374 %) approximated the yield predicted by the quadratic model, suggesting the reasonable soundness of the employed model and RSM when it comes to optimizing the parameters of extraction. In addition, considerable antibacterial activities of extracted essential oil against four bacteria cultures, in particular, S. aureus was recognized
Microencapsulation of Lemongrass (Cymbopogon citratus) Essential Oil Via Spray Drying: Effects of Feed Emulsion Parameters
The purpose of this study was to attempt the encapsulation of lemongrass (Cymbopogon citratus) essential oil utilizing spray drying technique. An array of process parameters including concentration of wall (15–30%), type of wall materials (maltodextrin, maltodextrin and gum Arabic mixture), and concentration of essential oil (0.5–2.0%) were thoroughly investigated. The results show that the use of sole maltodextrin as encapsulant gave microcapsules characteristics comparable to that of powder produced using maltodextrin and gum Arabic mixture. The encapsulation process that was performed with maltodextrin at the concentration of 30% as wall material and lemongrass essential oil at the concentration of 1.5% as core material showed highest drying yield (84.49%), microencapsulation yield (89.31%) and microencapsulation efficiency (84.75%). Encapsulated essential oils retained most of their major constituents in comparison with the bare essential oils without any significant compromise in product quality
Response surface modeling and optimizing conditions for anthocyanins extraction from Hibiscussabdariffa L. (Roselle) grown in Lam Dong, Vietnam
Hibiscus sabdariffa L. (Hs, roselle; Malvaceae) is a common ingredient used in the food and pharmaceutical industries for color and health benefits. Anthocyanins along with protocatechuic acid and quercetin have been recognized as bioactive compounds in Hibiscussabdariffa L. aqueous extracts. In this work, Response Surface Methodology was implemented together with Box-Behnken experimental design to investigate the impacts of process variables on anthocyanin extraction yields from Hibiscus sabdariffa L. (Roselle) grown in Lam Dong, Vietnam. The effects of three independent variables; namely the extraction temperatures of solvent ethanol (X1); the duration of extraction (X2); solid-liquid ratios (X3) on the total anthocyanins content (Y1) were explored. The optimization model showed that with the solid liquid ratio 7.7:1, extraction time 33.29 min, and temperature 56.9°C, the highest anthocyanin concentration of 186.006 mg/L was obtained. Hibiscussabdariffa L. anthocyanin yield detailed significant correlation with high F values, low P values (<0.0001), and desirable determination coefficient (R2 = 0.9770). The resulting quadratic model could be used to predict yields with given conditions. Actual experimental verification and residual testing revealed that the actual anthocyanin yields could be accurately predicted by the model
Functionalizing multifunctional Fe3O4 nanoparticle-based biocompatible, magnetic and photoluminescent nanohybrids: preparation and characterization
A combination of ring-opening polymerization (ROP) and coordination chemistry methodology has been expanded for the synthesis of a multifunctional, biocompatible, magnetic, luminescent nanohybrid complex comprising magnetite (Fe3O4) nanoparticles (MNPs), poly(ε-caprolactone) (PCL) and europium ions (Eu3+). The structural and morphological characteristic of the nanohybrid intricate were studied by appropriate spectrum and physical researches. The superparamagnetic behaviour and unique Eu3+ fluorescence properties with a high emission intensity of MNP-PCL-Eu3+ were investigated via measurements with a superconducting quantum interference equipment magnetism and fluorescence spectroscopy