Esterification Between Citric Acid and Callistemon citrinus, Rice-Husk, Garcinia dulcis Catalysed by Citric Acid’s-H+- Monomers and Polymers Formation Mechanism
Andry Tahina Rabeharitsara,
Sedraniaina Domoina Marie Esperance,
Ny Idealy Elite Randriamanantena,
Raïssa Faneva Mampitefa,
Nambinina Richard Randriana
Issue:
Volume 8, Issue 2, April 2020
Pages:
31-54
Received:
25 March 2020
Accepted:
10 April 2020
Published:
28 April 2020
Abstract: Esterification between citric acid molecules and molecules of Callistemon citrinus, rice husk and Garcinia dulcis (pulp-peel and pips) were carried out such as the citric acid molecules quantities (moles) were negligible against to these raw materials’ reactive molecules quantities (moles). Results showed generally an important initial, total conversions (after 60 minutes) of citric acids molecules which confirmed the essential role of raw materials’ aromatics molecules characterized by their alkene organic-function titrated with HF-0.00261N (Hydrofluoric acid) as support of citric acid’s protonic acid H+ catalyst (a portion of the carboxylic acids’ citric acid molecules used), support of non-ionic citric acid’s carboxylic acid (a portion of the carboxylic acids’ citric acid molecules used) and support of raw materials molecules reagents. So, the citric acid partial order of esterification of these used raw materials (Callistemon citrinus, rice husk and Garcinia dulcis (pulp-peel and pips)) with citric acid molecules were determined. Also, the brown citric acid equivalent monomers formed during esterification were calculated and their evolution were followed for all raw materials and results allowed to determine the citric acid’s protonic acid activities. In the same time, relationship between raw materials’ external specific surfaces, estimated by calculated and measured densities, and conversion or brown citric acid equivalent formed were established to conduct finally at the catalyst turnover. The variation of alkene organic-function concentration and/or quantities not only in solution but also in all by-products allowed to an ionic mechanism of these esterification with citric acid catalyzed by citric acid’s protonic acid H+ (a portion of the carboxylic acids’ citric acid molecules used) supported on all raw materials’ aromatics molecules and fiber structures in glass-flask where not only carbonic acids molecules but also hydrogens molecules gas were emitted. Finally, seeing that a non-negligible alkene organic-function quantities were titrated on all by-products, their valorization as catalytic support of citric acid molecules polymerization were carried out and a procedure constituted principally with estimation of dichloromethane and hexane insoluble/soluble products, titration with HF-0.00261N of the unsaturated organic-function in hexane soluble products and titration with NaOH-0.05N of the black citric acid equivalent quantities evolutions were established and the results confirmed the ionic mechanism of esterification with citric acid molecules during which not only carbonic gas and hydrogen gas were emitted but also new monomers and each equivalent saturated products (characterized by their globally white color and unsaturated organic-function titrated with HF-0.00261N), new polymers and poly-polymers (characterized by their globally black color and titrated with NaOH-0.05N) different to that obtained with radical mechanism catalyzed by Lewis acid sites were formed.
Abstract: Esterification between citric acid molecules and molecules of Callistemon citrinus, rice husk and Garcinia dulcis (pulp-peel and pips) were carried out such as the citric acid molecules quantities (moles) were negligible against to these raw materials’ reactive molecules quantities (moles). Results showed generally an important initial, total conve...
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Enhancement of Blood Cholesterol Level Relating to Edible Reused Cooking Oil Uptake in White Experimental Albino Rats
Mutaz Mohamed Ahmed Elshiekh
Issue:
Volume 8, Issue 2, April 2020
Pages:
55-62
Received:
7 December 2019
Accepted:
6 January 2020
Published:
28 May 2020
Abstract: Reusing cooking oil in food preparation, especially during deep-frying is a common practice to save costs. Repeated heating of the oil accelerates oxidative degradation of lipids leading to severe changes in lipid profile of the blood and forming hazardous reactive oxygen species which depletes the natural antioxidant contents of the cooking oil leading to pathologies such as hypertension, diabetes and vascular inflammation. The main objective of this work is to investigate the effect of the reused edible cooking oil uptake with the plasma cholesterol level in some experimental animals. Twenty adult male swiss albino (SWR) rats, weighing 120-200g body weight were housed within the premises of the medicinal and aromatic plant research institutes, national center for research Khartoum. They were randomized to one of the following experimental groups, with five animals per group: Group 1 the Normal group were administered normal diet (control group), Group 2 the experimental group were administered high-fat diet with low dose reused oil injection, Group3 the experimental group were administered high-fat diet with high dose reused oil injection, Group4 the experimental group were administered high –fat diet (disease group). Randomly fasting blood cholesterol level was done in 20 rats to identify the level of cholesterol before the administration of special diet that contain high saturated fat and cholesterol powder to elevate the level of cholesterol in albino rats. Rats of group two were injected with 1.5 ml/kg reused oil as a low dose and rats of group three will be injected with 3.0 ml/kg reused oil as a high dose. blood sampling and cholesterol level determination were done once a week for each rat separately for four weeks. Concerning the average cholesterol level of group 1 rats, it showed a narrow range elevation for the consecutive four weeks respectively. Group 2 rats shows a considerable range of average cholesterol level elevation. For rats of group 3 we expect a significant average cholesterol level elevation starting from the fasting period up to the fourth week, as the rats of this group were injected with 3 ml/kg (considered as a high dose) reused oil in addition to the high cholesterol diet and this is exactly what we observed. The average cholesterol level of group 4 rats was moderately elevated.
Abstract: Reusing cooking oil in food preparation, especially during deep-frying is a common practice to save costs. Repeated heating of the oil accelerates oxidative degradation of lipids leading to severe changes in lipid profile of the blood and forming hazardous reactive oxygen species which depletes the natural antioxidant contents of the cooking oil le...
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