scholarly journals EKSTRAK DAUN SIRIH HIJAU DAN MERAH SEBAGAI ANTIOKSIDAN PADA MINYAK KELAPA

2013 ◽  
Vol 2 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Hermiati ◽  
Naomi Yemima Manalu ◽  
Mersi Suriani Sinaga
Keyword(s):  
Antioxidant Activity ◽  
Solvent Extraction ◽  
Leaf Extract ◽  
Coconut Oil ◽  
Operating Conditions ◽  
Raw Material ◽  
Optimum Operating ◽  
Color Test ◽  
Betel Leaf ◽  
Material Powder

Extraction is the separation of a substance from the mixture, with the distribution of a solute between two solvents which can not be mixed to fetch solute from one solvent to another solvent. The purpose of this study was to determine the antioxidant activity found in betel leaf extract for coconut oil numbers peroxide analysis, antioxidant resistance, with Lovibond color test and to found variations in betel leaf types that produce the optimum operating conditions of antioxidants. In this study, green and red betel leaves extracted by using ethanol solvent, the extract is added to coconut oil and then tested peroxide number and color levels. The results obtained in this study were able to lower the number of betel leaves peroxide by 55.13% with the best optimum condition; volume of 150 ml of solvent, extraction time of 75 minutes, and stirring speed of 300 rpm for the raw material powder of red betel leaf.

Removal of Iron from Metallurgical Grade Silicon with Pressure Leaching

2011 ◽  
Vol 675-677 ◽  
pp. 873-876 ◽  
Author(s):  
Ke Qiang Xie ◽  
Zhan Liang Yu ◽  
Wen Hui Ma ◽  
Yang Zhou ◽  
Yong Nian Dai
Keyword(s):  
Particle Size ◽  
Reaction Time ◽  
Removal Efficiency ◽  
Acid Concentration ◽  
Operating Conditions ◽  
Raw Material ◽  
Optimum Operating ◽  
Pressure Leaching ◽  
Metallurgical Grade Silicon ◽  
Grade Silicon

In this paper, removal of iron from metallurgical grade silicon with pressure leaching is carried out. We investigated the factors such as the concentration of hydrochloric, particle size of raw material ground, temperature, pressure and reaction time, which influenced on the removal of iron. The results show that the optimum operating conditions for pressure leaching in hydrochloride are: acid concentration 4 mol/L, diameter for raw material less than 50 μm, leaching temperature 160 0C，leaching pressure 2.0 MPa, leaching time 2.0 h. The content of iron residual in MG-Si powder was reduced to about 200 ppmw. The removal efficiency of iron is up to 90.90 %.

scholarly journals Characterization and Beneficiation of an Egyptian Nepheline Syenite Ore

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Abdel-Zaher M. Abouzeid ◽  
Abdel-Tawab A. Negm
Keyword(s):  
Magnetic Separation ◽  
Nepheline Syenite ◽  
Eastern Desert ◽  
Operating Conditions ◽  
Raw Material ◽  
Optimum Operating ◽  
Oxide Content ◽  
Radioactive Elements ◽  
Original Rock ◽  
Alumina Recovery

Nepheline syenite ore is an essential constituent in ceramics and glass raw material meals, as a flux and as a source of alumina. The natural nepheline syenite rocks contain some undesired minerals, which are usually eliminated or reduced to the allowable limits by beneficiation. The present paper is concerned with characterization and beneficiation of an Egyptian nepheline syenite rock, at Abu Khruq locality, Eastern Desert, Egypt. The ore is exceptionally hard, with high crushing strength of 875 kg/cm2, and iron oxide content of about 6.5%. The grain size of the constituents is relatively large. In some samples, the iron oxides are disseminated within the feldspars and nepheline syenite crystals, or in cracks and fissures within the feldspars crystals. The rock contains some environmental hazardous elements such as uranium, thorium, and radon. Magnetic separation and flotation techniques were applied, separately or in combination. Under optimum operating conditions, magnetic separation followed by reverse anionic flotation gave a concentrate assaying 0.2% Fe2O3 and about 24% Al2O3 at alumina recovery of about 80%. The radioactive elements were reduced in the concentrate to lower levels than their levels in the original rock.

scholarly journals Antioxidant activity of eugenol in Piper betel leaf extract

2020 ◽  
Vol 9 (1) ◽  
pp. 327 ◽  
Author(s):  
Anjum Aara ◽  
Vani Chappidi ◽  
MadhavanN Ramadas
Keyword(s):  
Antioxidant Activity ◽  
Leaf Extract ◽  
Betel Leaf ◽  
Piper Betel Leaf

scholarly journals Synthesis of tert-amylbenzene for side-chain alkylation of cumene catalyzed by a solid superbase

2021 ◽  
Vol 10 (1) ◽  
pp. 874-881
Author(s):  
Xin Zhou ◽  
Ge Gao ◽  
Guangxiang He ◽  
Xiaoyan Guo ◽  
Haibo Jin ◽  
...  
Keyword(s):  
Reaction Temperature ◽  
Catalytic Reaction ◽  
Catalyst Concentration ◽  
Operating Conditions ◽  
Raw Material ◽  
Optimum Operating ◽  
Side Chain ◽  
Operational Flexibility ◽  
Deactivation Of Catalyst ◽  
Solid Superbase

Abstract The side-chain alkylation of cumene and ethylene over a solid superbase catalyst K/KOH/γ-Al2O3 is investigated. The effects of the reaction temperature, pressure, and time on the conversion of cumene and selectivity of tert-amylbenzene (TAB) are discussed. The experimental results show that the conversion of cumene to tert-pentylbenzene increases with the increase in reaction temperature and ethylene pressure. The catalytic reaction has certain operational flexibility in terms of the reaction temperature, pressure, and time. In addition, the catalytic reaction can achieve directional conversion. The optimum operating conditions are obtained using a single factor test. The conversion of cumene is 99.8% and the selectivity toward TAB is 97.9% under catalyst concentration of 4 wt%, reaction temperature of 55°C, reaction pressure of 0.45 MPa, and reaction time of 30 min. The deactivation of catalyst is mainly caused by oxygen and water in the raw material.

PENGARUH WAKTU HIDROLISA DAN KONSENTRASI ASAM PADA HIDROLISA PATI KENTANG DENGAN KATALIS ASAM

EKUILIBIUM ◽  
2014 ◽  
Vol 13 (2) ◽  
Author(s):  
Inayati Inayati
Keyword(s):  
Acid Concentration ◽  
Reaction Rate ◽  
Acid Catalyst ◽  
Glucose Production ◽  
Operating Conditions ◽  
Raw Material ◽  
Optimum Operating ◽  
Pseudo First Order Reaction ◽  
Glucose Content ◽  
Glucose Syrup

<p>Abstract: Potato has high content of carbohydrate (starch), so it can be used as raw material<br />for the glucose production. The basic principle to produce glucose from potatoes is hidrolysis of<br />polysaccharides (starch) into monosaccharides and disaccharides. In this work, potatoes were<br />converted into glucose syrup by hydrolysis using hydrochloric acid as catalyst. The aim of this<br />work is to study the effect of acid concentration on the reaction rate. Hydrolysis was carried out<br />with constant parameters, namely 20 gram of starch, 300 rpm of its rotational speed and the<br />operating temperature of 100°C, and variable parameters including acid concentration (0.5 N, 1<br />N, 1.5 N, and 2 N) and the hydrolyzing time (30 minutes, 60 minutes, 90 minutes, 120 minutes,<br />and 150 minutes). The glucose content were analyzed using the Lane-Eynon methode. The<br />data analysed showed the higher concentration of acid and time of hydrolysis caused higher<br />glucose formed. Optimum operating conditions was at 2 N HCL as catalyst. In this study, by<br />assuming a pseudo-first order reaction, the reaction rate constants obtained at range of 0.0047<br />to 0.0076/min.<br />Keywords: Potatoes, Starch, Hydrolysis, Acid concentration, Acid catalyst</p>

scholarly journals Effect of Microencapsulation Techniques on Physical and Chemical Characteristics of Functional Beverage Based on Red Betel Leaf Extract (Piper crocatum)

2020 ◽  
Vol 23 (8) ◽  
pp. 276-282
Author(s):  
Mega Safithri ◽  
Susi Indariani ◽  
Rosalina Yuliani
Keyword(s):  
Antioxidant Activity ◽  
Total Phenolic Content ◽  
Leaf Extract ◽  
Sensory Quality ◽  
Phenolic Content ◽  
Total Phenolic ◽  
Betel Leaf ◽  
Functional Drink ◽  
Physical And Chemical

Functional drinks based on red betel leaf extract have antioxidant activity, but they still have a bitter taste. This study aims to determine the effect of microencapsulation on phenol content, antioxidant activity, and sensory quality of functional drinks based on betel leaf extract. Microencapsulation of functional drinks was made using maltodextrin coatings with concentrations of 10% and 20%. Antioxidant activity was tested by the CUPRAC method. The ready to drink (RTD) functional drink has a total phenolic content and antioxidant activity of 782.30 ± 2.54 mg GAE/g and 1660.19 ± 31.67 µmol Tr/g, respectively. These values are higher than microencapsulated functional drinks with maltodextrin (MM). The microencapsulated functional drink with 10% maltodextrin coating (MM10) is the chosen formulation since it has the smallest particle size (1.283 µm), total phenolic content of 12.90 ± 0.01 mg GAE/g and antioxidant activity of 189.41 ± 1.88 µmol Tr/g. Microencapsulated functional drinks provide sensory quality that is not significantly different (p <0.05) from ready to drink (RTD) drinks.

scholarly journals Purification of Arabinoxylans from Corn Fiber and Preparation of Bioactive Films for Food Packaging

Membranes ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 95 ◽  
Author(s):  
Maria Serra ◽  
Verónica Weng ◽  
Isabel M. Coelhoso ◽  
Vitor D. Alves ◽  
Carla Brazinha
Keyword(s):  
Antioxidant Activity ◽  
Ferulic Acid ◽  
Food Packaging ◽  
Animal Feed ◽  
Edible Films ◽  
Operating Conditions ◽  
Corn Fiber ◽  
Raw Material ◽  
Added Value ◽  
Permeate Flux

Corn fiber, a by-product of the starch industry, is presently incorporated in animal feed. However, it has arabinoxylans as added-value components (besides ferulic acid) that should be valorized. In this work, the raw material, a fraction enriched in arabinoxylans from corn fiber, previously produced by alkaline extraction from corn fiber and pre-concentrated by ultrafiltration, was further purified. The use of ultrafiltration operated in diafiltration mode (dia-ultrafiltration) was evaluated for the purification of the arabinoxylans fraction. The objective was to maximize the removal of the small contaminants from the fraction and to maximize the permeability and/or the permeate flux, by selecting the relevant operating conditions involved in this process. The removal of contaminants (%) was estimated when their apparent rejection stabilized. Edible films were produced, from the resultant purified arabinoxylans fraction, using glycerol as plasticizer (30% dry basis). Additionally, films with the incorporation of ferulic acid were developed, in order to obtain barriers with antioxidant activity. The films were characterized in terms of mechanical properties, antioxidant activity and permeability to water vapor. The films prepared presented a good potential to be used as packaging for food products with low water content.

scholarly journals Optimization of Phenolics and Flavonoids Extraction Conditions and Antioxidant Activity of Roasted Yerba-Mate Leaves (Ilex paraguariensis A. St.-Hil., Aquifoliaceae) using Response Surface Methodology

2014 ◽  
Vol 86 (2) ◽  
pp. 923-934 ◽  
Author(s):  
DÉBORA C. BASSANI ◽  
DOMINGOS S. NUNES ◽  
DANIEL GRANATO
Keyword(s):  
Antioxidant Activity ◽  
Response Surface Methodology ◽  
Response Surface ◽  
Desirability Function ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Ilex Paraguariensis ◽  
Yerba Mate ◽  
Experimental Conditions ◽  
Highly Correlated

This study focused on maximizing the extraction of total phenolics and flavonoids as well as the antioxidant activity measured by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay from roasted yerba mate (Ilex paraguariensis) as a function of time (5, 7.5 and 10 min) and temperature of extraction (60, 75 and 90°C). The data were subjected to Response Surface Methodology and the results showed that polynomial equations were significant, did not present lack of fit, and presented adjusted determination coefficients above 98%, proving their suitability for prediction purposes. Using the desirability function, the optimum operating conditions to obtain a higher extraction of antioxidants was found to be 10 min of extraction at 90°C, and the tea prepared under these experimental conditions presented 427.74 mg of gallic acid equivalents per liter and 80.02% of inhibition of the DPPH radical. The flavonoid content was highly correlated (r = 0.9046, p < 0.001) to the antioxidant capacity.

scholarly journals Pengembangan Mesin Pencacah Tandan Kosong Sawit (TKS) dengan Metode Pemotongan Crusher

2014 ◽  
Vol 9 (2) ◽  
pp. 42
Author(s):  
Junaidi - ◽  
Anwar Kasim ◽  
Aidil Zamri ◽  
Sir Anderson
Keyword(s):  
Large Scale ◽  
Elastic Fiber ◽  
Testing Machine ◽  
Operating Conditions ◽  
Raw Material ◽  
Optimum Operating ◽  
Design Parameters ◽  
Small Scale ◽  
Processing Unit ◽  
Engine Capacity

Palm empty fruit bunches (EFB) fiber content ± 70 % and can be used for elastic    fiber, matrix, mattresses, rugs and raw material fiber -based composite board products, but until now has not been utilized to the fullest . The problem is not the availability of processing unit generates EFB fiber in small scale . One of them is the processing unit thrasher EFB. EFB counter technology that exists today is a large scale that can only be owned by the oil palm industry with a capacity of ± 4,124 kg/hour. For small-scale fiber industry needs a minimum engine capacity of census enumerators ± 300 kg/hour, but this machine is not yet commercially available.In general, the purpose of this research is small scale EFB cutting machines with a capacity of 200-300 kg/hour, the design parameters and identify optimum operating conditions for each component with the technical test of the prototype. From the results obtained machine design an engine capacity of 300 kg/hour, with a few major components, namely counter unit, unit funnel in and out, frame and drive unit . From the results of design calculations obtained engine power 15 hp motor drive with 1450 RPM rotation with 3 phase. From the results of the testing machine in the first enumeration results obtained by the size of the pieces of shredded EFB ± 7 x 7 ( cm ), while the second enumeration stage shredded EFB size becoming smaller ± 3 x 3 ( cm ).

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