USAGE OF POTASSIUM METHOXIDE IN METHANOL AND POTASSIUM TERT-BUTOXIDE IN TERT-BUTANOL AS CATALYSTS IN INTERESTERIFICATION OF RAPESEED OIL

Author(s):  
Elina Sile
2018 ◽  
Vol 762 ◽  
pp. 158-162 ◽  
Author(s):  
Elina Sile ◽  
Valdis Kampars ◽  
Zane Sustere

Two catalytic systems (CH3OK/CH3OH and CH3OK/tert-BuOH) were tested to estimate competitive interesterification-transesterification processes of rapeseed oil with methyl acetate. Catalyst completely dissolves in methanol, while in tert-butanol suspension was obtained. With CH3OK/CH3OH catalytic system high FAME content was obtained (86 wt%), but triacetin content was negligible and without FAME mostly transesterification products of oil and triacetin were observed (up to 94 wt% of all products). When CH3OK/tert-BuOH catalytic system was used, only interesterification of oil proceeded, nevertheless the composition of product complicated the interesterification of triacetin with tert-butanol.


1992 ◽  
Vol 67 (03) ◽  
pp. 352-356 ◽  
Author(s):  
Marja Mutanen ◽  
Riitta Freese ◽  
Liisa M Valsta ◽  
Irma Ahola ◽  
Antti Ahlström

SummaryIn this highly controlled trial, 26 normolipidemic men (average age 28 years, range 18 to 60) were fed a baseline diet high in milk fat (MF) (fat 36% of energy, saturates 19%, monounsaturates 11%, polyunsaturates 4%), followed by a diet high in sunflower oil (SO) (fat 38% of energy, saturates 13%, monounsaturates 10%, polyunsaturates 13%) and another diet high in low erucic-acid rapeseed oil (RO) (fat 38% of energy, saturates 12%, monounsaturates 16%, polyunsaturates 8%). All diets were mixed natural diets with the same cholesterol contents. The baseline milk fat diet was given for 14 days and the oil diets for 24 days in a blind cross-over design. The platelet in vitro aggregation (slope %/min) induced by 1, 2 and 3 pM ADP and collagen (25 pg/ml PRP) was highly significantly (p <0.001) increased after both oil diets when compared with the results from the milk fat diet. The aggregation pattern determined by threshold collagen concentration confirmed increased collagen sensitivity of the platelets after the rapeseed oil diet (p <0.001). The enhancement of platelet aggregation was associated with increased in vitro platelet thromboxane production after the oil diets vs. the milk fat diet (p <0.05 after the sunflower oil diet and p <0.001 after the rapeseed oil diet).


2015 ◽  
Vol 37 (2) ◽  
pp. 162-167
Author(s):  
V.A. Vilensky ◽  
◽  
L.V. Kobrina ◽  
S.V. Riabov ◽  
Y.Y. Kercha ◽  
...  

2019 ◽  
Vol 56 (4) ◽  
pp. 279-286 ◽  
Author(s):  
Tomasz Wasilewski ◽  
Yong-Qiang Sun ◽  
Wiesław Hreczuch ◽  
Artur Seweryn ◽  
Tomasz Bujak

1987 ◽  
Vol 52 (10) ◽  
pp. 2482-2491 ◽  
Author(s):  
Ján Urban ◽  
Petr Kuzmič ◽  
David Šaman ◽  
Milan Souček

Anaerobic photolysis of dimethoxynitrobiphenyls IIIa-VIa in aqueous alkaline tert-butanol gave products of nucleophilic photosubstitution of methoxyl by hydroxide anion, while the dimethoxybiphenyls Ia and IIa were found unreactive. Regioselectivity of the reaction was examined in view of a possible “extended meta activation” by the nitro group. The most reactive substrate IIIa gives both C-3 and C-4 substitution products with an unsubstantial preference for the latter, which opposes the “extended meta selectivity” rule. All of the other compounds obey the rule, and 3,4-dimethoxy-3'-nitrobiphenyl (IVa) even displayed absolute selectivity by yielding C-3 substituted compound as the only product. 2,5-Dimethoxy substituted compounds underwent photosubstitution which much lower quantum yields than their 3,4-substituted counterparts, most probably due to some steric hindrance of conjugation. Similarly, 3-nitro-substituted biphenyls exhibited much lower overall reactivity than 4-nitro derivatives.


2020 ◽  
Vol 739 ◽  
pp. 137045
Author(s):  
Kazunari Takaya ◽  
Yuya Hasegawa ◽  
Tetsuo Koizumi
Keyword(s):  

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