maximum extraction
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Etnobotanika ◽  
2021 ◽  
Vol 1 (1) ◽  
pp. 57-69
Author(s):  
Danijela Kostić ◽  

Stara Planina Mt is rich in medicinal plants, that are natural sources of various bioactive substances and have many useful medicinal properties. Rosehip, the fruit of wild rose (Rosa canina L.) is very popular and widely used. There is extensive empirical evidence of its therapeutic effects. The high content of vitamins, organic acids, phenolic compounds, carotenoids and pleasant taste define it as a valuable dietary supplement. There are different procedures for making rosehip teas. In this paper, we have optimized the process of preparation of rosehip tea from the aspect of maximum extraction and preservation of vitamin C content in tea. The antioxidant activity of aqueous extracts of rosehips, depending on the extraction time and the temperature at which the extraction is performed, was also examined..The free radical scavenging activity of the plant extracts was analyzed by using the 2.2-diphenyl-1-picrylhydrazyl (DPPH) assay. Optimal conditions are 30 minutes and a temperature of 40 °С. In this way, vitamin C is best extracted and its stability is preserved, which results in the high antioxidant activity of the tested teas.


2021 ◽  
Author(s):  
Francesco Bogliacino ◽  
Cesar Mantilla ◽  
Daniel Niño Eslava

We designed and conducted an experiment of common-pool resource management involving economic and political inequality. Participants are assigned to different types differing in their endowments-Poor, Middle and Rich-and play an appropriation dilemma, with and without a voting procedure to select a quota limiting maximum extraction. Political inequality is introduced by allocating a higher likelihood to select the voted quota of a given player type: in the Ptochocracy treatment, the "Poor" type has a higher chance of setting her choice as quota; whereas in the Demarchy and Plutocracy treatments, this is true for the "Middle" and "Rich" types, respectively. These are contrasted with Democracy, where the votes of all three types are equally likely to be selected. Theoretically, each player type selfishly prefers the quota closer (i.e., one unit below) their endowment, although the lower quota would be socially desirable.We find that participants voted for the selfishly preferred quota between half and two-thirds of the time, and the introduction of these quotas decreased the absolute extraction in about 17.5%, even though participants were more likely to choose extraction levels closer to their maximum capacity (now set by the quota). Nonetheless, we do not find systematic differences in extraction patterns between treatments.


2021 ◽  
Vol 8 (1) ◽  
pp. 67
Author(s):  
Sri Indriati ◽  
Muhammad Yusuf ◽  
Riskayanti Riskayanti ◽  
Nur Amaliah ◽  
Mahyati Latief ◽  
...  

Safflower, were extracted using propanol solvent at different time intervals: 10, 20, and 30 min at a constant temperature of 40°C. The extracts were analyzed by GC/MS technique. The major compounds identified were tetrapentacontane, tetracontane, triacontanol, gamma sitosterol, myristic acid, linoleic acid, stearic acid, palmitic acid, oleic acid, and lauric acid. However, some levels of palmidrol, beta-amyrin, cubenol, and tocopherol were also found in safflower extracts. Most of the volatile compounds were detected between 10–30 min time of extraction. The 30 min time of extraction also showed the maximum content of polyphenols and antioxidants in safflower extracts. Thus, 30 min was suggested as the most suitable time for maximum extraction of bioactive volatiles, antioxidants, and polyphenols from Safflower using propanol solvent.


2021 ◽  
Vol 8 (1) ◽  
pp. 44-49
Author(s):  
Xuan Dinh Luu ◽  
Thanh Thuy Nguyen ◽  
Ba Thuan Le ◽  
Mai Huong Le Thi

The solvent extraction is one of the most common method for separating Th from solution. Primary amine has higher selectivity for the extraction of Th(IV) than U(VI) and RE(III) in sulfate media. N1923 (a primary aliphatic amine with amino nitrogen linked to a secondary carbon consisting of branched alkyl groups in C19–23 range) is commonly used to extractTh. At room temperature using 0.1M N1923 amine as solvent in this work, the results showed thatthorium maximum extraction capacity was about 2.5g/L with concentration of sulfuric acid in the aqueous phase was 1M and for 3 minutes shaking. At room temperature for 3 minutes shaking the best conditions for scrubbing processwas using the mixture of acids H2SO4 0.2M and HNO3 0.1M, result inover 75%, Th was scrubbed in the aqueous phase only 0.7%. The separation of Th from leachate of monazite sulphation process was carried out on a multistage continuous flow extraction device (12 boxes), the thorium purity was 98%. Therefore, the use of amine solvents can purify thorium from rare-earth solutions in a sulfate medium


Biology ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 815
Author(s):  
Guo Liu ◽  
Tao Hou ◽  
Shenglan Guo ◽  
Hongyu Lin ◽  
Meng Chen ◽  
...  

The immature honey pomelo fruit (IPF) is a huge agro-industrial by-product generated during pomelo planting. Although IPF is rich in nutrients, more than 95% of IPF is discarded annually, which causes resource waste and a serious environmental problem. Here, we report a novel continuous phase transition extraction technology (CPTE) to improve the comprehensive utilization of IPF by sequentially generating high value products and solve pollution problems related to their disposal. First, essential oil was successively extracted by CPTE at a yield of 1.12 ± 0.36%, in which 43 species were identified. Second, naringin extraction parameters were optimized using the response surface methodology (RSM), resulting in a maximum extraction rate of 99.47 ± 0.15%. Finally, pectin was extracted at a yield of 20.23 ± 0.66%, which is similar to the contents of commercial pectin. In conclusion, this study suggested that IPF was an excellent potential substrate for the production of value-added components by CPTE.


2021 ◽  
Vol 13 (4) ◽  
Author(s):  
Moussa Koulibaly ◽  
Tatiana Chekushina ◽  
Alexey Yankevskiy

The article discusses the issues of increasing the efficiency of extraction of gold-bearing ores from poor ores using gravity using combined geotechnologies at the Sigiri mine (Republic of Guinea). Gravity Recoverable Gold (GRG) is defined as gold present in a particle in sufficient quantities to be selectively recovered from waste rock by gravity methods. Since Guinea is one of the ten leaders among the countries of the African continent in terms of gold reserves (2019 — 700,000 tons), it should be taken into account that the complex of measures for ore processing includes crushing modules interconnected during the technological process, grinding-gravity module, flotation module and metallurgical a module that affects the solution of the problem of integrated development of subsoil in the generally accepted understanding and this is the maximum extraction of recorded reserves from the subsoil and useful components from mined ore. The author presents the influence of the centrifugal concentrator Nelson (Knelson) on increasing the degree of gold recovery from gold-bearing poor ores under high climatic conditions. Increase in gold production by the GRG test method due to the destruction of the ore structure and a significant decrease in density, as well as an increase in the opening of minerals using gravity up to 63 %. Thus, the optimization is classified as medium-coarse gold.


2021 ◽  
Vol 20 (2) ◽  
pp. 219-229
Author(s):  
Feng Gao ◽  
Tao Chen ◽  
Liang Li

In this article, calcium salts were added into the hydrofluoric acid-sulfuric acid (HF-H2SO4) leaching system, and their effects on the extraction of potassium from phosphorus-potassium associated mineral (mineral deposits containing Ca5(PO4)3F (fluorapatite) and KAlSi3O8 (potassium feldspar)) were investigated. KAlSi3O8 was converted into water-soluble potassium fertilizers, and important factors affecting the extraction, including dosages of H2SO4, types and dosages of calcium salts were studied. The results showed that the maximum extraction of 75.3 wt.% was obtained with H2SO4 (70 wt.%) dosage of 5 mL. When the reaction was added with 0.15 g CaSO4, the extraction rate of K of 95 wt.% was achieved, which was an increase by 19.7 wt.% compared with that without calcium salts. Moreover, the Eh-pH diagrams for K-Si-(P)-(F)-(Ca)-H2O systems were plotted and applied to analyze the mechanism of potassium extraction in the HF-H2SO4 reaction system. The analysis demonstrated that with the presence of F-, the formation of fluoro-complexes enlarged the stable regions of soluble phosphorus (KPF6) and silicon (K2SiF6). However, when calcium salts were added, such region decreased with the increase of [Ca2 +]; and such trends suggested that [K+] could be enhanced by adding [Ca2 +] during the leaching process.


Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4363
Author(s):  
Marija Banožić ◽  
Ines Banjari ◽  
Ivana Flanjak ◽  
Mate Paštar ◽  
Jelena Vladić ◽  
...  

This study intends to valorize by-products of the industrial processing of tobacco to obtain nicotine and phenolics as value-added compounds. Three influential parameters of the microwave-assisted extraction-MAE (temperature, treatment time, and solvent/solid ratio) were studied for the optimization of the extraction protocol for tobacco leaves and three types of waste—scrap, dust, and midrib, respectively. Nicotine was the dominant bioactive compound in all extracts, ranging from 1.512 to 5.480% in leaves, 1.886 to 3.709% in scrap, 2.628 to 4.840% dust, and 0.867 to 1.783% in midrib extracts. Five phenolic compounds were identified and quantified, predominated by chlorogenic acid and rutin. Additionally, total phenol content and antioxidant activity were determined using spectrophotometric assays. Optimization was performed in two aspects: to obtain a maximum extraction yield with minimum nicotine content and to obtain a maximum extraction yield with maximum nicotine content. These findings demonstrate that tobacco waste is a valuable source of bioactive compounds and MAE can be a promising alternative technique to obtain extracts rich in targeted bioactive compounds, especially nicotine.


Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3783
Author(s):  
Itziar Egüés ◽  
Fabio Hernandez-Ramos ◽  
Iván Rivilla ◽  
Jalel Labidi

In the present work, the optimization of the extraction of antioxidant compounds from apple pomace using ultrasound technology as an environmentally friendly and intensification process was developed. Different sonication powers, extraction temperatures and extraction times were studied and their influence on extraction yield and characteristics of the extracted samples (total phenolic compounds, flavonoid content and antioxidant capacity) are presented. The elaborated experimental design and the analysis of Pareto and response surface diagrams allowed us to determine the optimal extraction conditions. The conditions that allow the maximum extraction of phenolic compounds were found at 20 min, 90 °C and 50% ultrasound amplitude. Nevertheless, at these conditions, the antioxidant capacity measured by DPPH decreased in the extracted samples.


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