76 research outputs found

    The effect if extraction time and sample ratio on the process of extracting active substances from Hawthorn (Crataegus Monogyna) using ultrasound

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    Ultrasound-assisted extraction (UAE) is one of the modern method that is applied today with the aim to decrease solvent consumption, shorten the extraction time, increase the extraction yield, and enhance the quality of extracts. In this paper, the effect of extraction time and the ratio of the sample to the solvent have been studied on the ultrasonic extraction of hawthorn fruits. The hawthorn fruit was collected from Normafa, Hungary. 10% ethanol and pure distilled water were used as extraction solvent. Folin-Ciocalteu method was performed to visualization of total phenolic compounds (TPC) and the ferric reduction antioxidant power (FRAP) method to quantify antioxidant activity in the extracts. Analyzing the results by two-way-ANOVA at significant level p < 0.05 by using SPSS software demonstrated that there is significant effect of time of extraction and the ratio of the sample to solvent. For TPC the best value was obtained at (9 min, 0.05 g/ml sample-solvent ratio) with a mean (451.106 ± 0.79 mg/L) by using 10% ethanol, and at (3 min, 0.075 g/ml sample-solvent ratio) with a mean (365.289 ± 15.96 mg/L) by using distilled water. While the best antioxidant activity was with a mean (223.033 ± 1.01 mg/L) at (9 min, 0.075 g/ml sample-solvent ratio) and (50.678 ± 2.02 mg/L) at (6 min, 0.1 g/ml sample-solvent ratio) by using the 10% ethanol and distilled water respectively. More work is needed to define better conditions for using the distilled water as a solvent in the ultrasonic extraction

    Comparison the Soxhlet and Supercritical Fluid Extraction of Nettle Root (Urtica dioica L.)

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    The leaves of stinging nettle (Urtica dioica L.) are used for medical purposes since centuries while the nettle roots are applied only in the last decades. According to the latest researches the root of nettle contains many important ingredients, for example scopoletin, sterols, fatty acids, polysaccharides, polyphenols, minerals, etc. The polyphenols have antioxidant effect, reduce the hematological disorders, but also have anti-cancer and anti-bacteriological effects. The H-donating ability expresses the antioxidant activity.In this study two kinds of extraction techniques and three kinds of solvents have been applied. The extraction techniques were: Soxhlet extraction with 96% ethanol, Soxhlet extraction with n-hexane and supercritical fluid extraction (SFE) with CO2. All the measurements and the analysises were repeated three times.Comparing the yields of the three extraction methods it was established that the highest yield value was reached by Soxhlet extraction with ethanol. The Soxhlet extraction and the supercritical extraction has lower yield, the total polyphenol content and the H-donating ability of these extracts were low

    The Application of Membrane Technology in the Concentration and Purification of Plant Extracts: A Review

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    The obtained plants and by-products during food and agricultural manufacturing processes are sources for many bioactive components that attract industrial and academic interest. The essential method of obtaining these bioactive components is the extraction process by using solvents. The efficiency of the extraction processes mainly depends on the choice and selectivity of these solvents. However, the most challenging step is recovering the components from the solvent to obtain the active part and pure products. In this recovery process, many methods were applied, such as evaporation and adding assistant chemicals, which had many downsides as energy consumption and unwanted product. Consequently, membrane technology such as microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), membrane distillation (MD), and osmosis distillation (OD) has been applied as a new approach in concentrating plants extract. Since this new approach has proved its efficiency in this field, the main objective of this paper is to provide a review of academic studies that have addressed using different membrane techniques to concentrate the plant extracts

    Microencapsulation Analysis Based on Membrane Technology: Basic Research of Spherical, Solid Precursor Microcapsule Production

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    The objective of the proposed investigation was to synthesis of precursor oil-carbohydrate microcapsule, suspended in water by membrane emulsification technology. To select the carrier material of precursor microcapsules, four different carbohydrates (maltodextrin, hydroxypropyl cellulose, potato starch and corn starch) were tested. Preliminary, zeta-potential, molecular weight and particle size of individual carbohydrate were estimated by Malvern Zetasizer instrument. Based on the results of the preliminary characterizations, maltodextrin was selected to carry out subsequent experiments. Maltodextrin suspended in oil and water were considered as dispersed phase and continuous phase respectively. An attempt has been made to remove the water, as well as to recover the microcapsules. It was observed that average particle size of synthesized microcapsule is 6.9 ÎĽm and stability of the microcapsule is at least 6 weeks

    Microencapsulation of Olive Oil: A Comprehensive Review

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    Olive oil has been received a great importance around the globe because it provides unique functional value. Olive oil prevents the risks of several chronic and acute metabolic disorders because it is enriched with monounsaturated fatty acids, antioxidant phenolic compounds, vitamin E and vitamin K. Unfortunately, oxidative deterioration of fatty acids in olive oil provides short shelf life and reduces biological activities. It is responsible for undesirable organoleptic properties. It may belief that one of the solutions to preserve the quality of olive oil is microencapsulation. In this review, comprehensive information about techniques to prepare olive oil microcapsule is represented. To prepare olive oil microcapsule, emulsification of olive oil with different wall materials (matrixes) has been adopted as a primary step. Subsequently, dehydration of emulsion by spray drying or freeze drying or coacervation process has been adopted to prepare olive oil microcapsule. Moreover, microcapsule of olive oil has been prepared by extrusion technology. Biopolymers, such as proteins and polysaccharides have been used as wall material for encapsulation of olive oil. As stable emulsification is one of important issue to produce microcapsule, several emulsifiers, such as lecithin, tween 20 have been used during emulsion preparation. Different characteristics of the microcapsule of olive oil are summarized because it is influenced by several factors during preparation of microcapsule. In later exercise, several applications of encapsulated olive oil in food, pharmaceutical and cosmetic industries are represented in comprehensive way. It may expect that this review article will receive attention in industries and academic sectors

    Effects of Static Mixing on the Ultrafiltration of Milk Whey

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    The promotion of efficiency and the reduction of energy consumption are very important tasks in every industrial process as well in food production. Although membrane filtration is a low-energy and environmental friendly separation method it still needs improvement in many fields. In our earlier research it was stated that a static mixer combined with ceramic tube membrane results higher permeate flux and lower specific energy consumption in case separation of oily wastewater. This paper deals with the extension of this combined method to the separation of milk whey. It was found that static turbulence promotion inside a tube membrane during ultrafiltration of whey can increase permeate flux and decrease energy consumption, inside a given spectra of operating parameters, compared to the conventional mode (when no static mixing applied in the process)

    Antimicrobial Effects of the Stinging Nettle (Urtica Dioica L.).

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    Nowadays increasing attention is being paid to herbs, one of the reasons is to avoid the undesirable side effects of synthetic drugs. This is the reason why the analysis of the antimicrobial activities of medicinal plants are increasingly in the focus of scientific experiments as well. One of the best-known medicinal plants is nettle. Among the nettle species in Hungary, Stinging nettle (Urtica dioica&nbsp;L.) can be found in the country and is most commonly utilised for medical purposes, with a focus on its leaves and roots. Nettle tea consumption is widespread in folk medicine for treating diabetes, allergies, abdominal pain, benign prostatic hyperplasia, rheumatoid arthritis and treatment of infections. This study gives a widespread summary of the reseach results about the antimicrobal impact of Stinging Nettle (Urtica dioica&nbsp;L.) in the scientific literature. The papers documented a positive effect of nettle for more than 30 Gram positive and Gram negative bacterias, yeasts and fungis
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