{"id":511,"date":"2016-09-06T20:42:37","date_gmt":"2016-09-07T01:42:37","guid":{"rendered":"http:\/\/www.bocsci.com\/blog\/?p=511"},"modified":"2016-09-06T20:42:37","modified_gmt":"2016-09-07T01:42:37","slug":"production-of-canolol-from-canola-meal-phenolics-via-hydrolysis-and-microwave-induced-decarboxylation","status":"publish","type":"post","link":"https:\/\/www.bocsci.com\/blog\/production-of-canolol-from-canola-meal-phenolics-via-hydrolysis-and-microwave-induced-decarboxylation\/","title":{"rendered":"Production of Canolol from Canola Meal Phenolics via Hydrolysis and Microwave-Induced Decarboxylation"},"content":{"rendered":"

Free radicals induce oxidative damage in vivo causing\u00a0aging and various diseases. They are also the major\u00a0cause for deterioration, quality loss, and shelf life reduction\u00a0in oils\/fats and fat-containing systems. There are many\u00a0studies on the antioxidative effects of natural extracts\u00a0derived from rapeseedm,\u00a0vegetables and olives. Most of these extracts contain water-soluble components as active ingredients. Thus, there is a need for naturally derived lipid-soluble antioxidants for utilization in\u00a0oil\/fat products as well as in vivo. Examples of lipid-soluble antioxidants include butylhydroxyanisole<\/a> (BHA), butylhydroxytoluene<\/a> (BHT), tert-butylhydroquinone<\/a> (TBHQ)\u00a0and propylgallate<\/a>\u00a0(PG). Their safety has been extensively\u00a0questioned and attempts to eliminate them from human diet\u00a0continued. Consequently, there is a need for developing\u00a0highly active fat-soluble antioxidants from natural sources,\u00a0especially from the under-utilized by-products such as\u00a0meals.<\/p>\n

2,6-Dimethoxy-4-vinylphenol <\/a>(known as canolol or\u00a04-vinylsyringol) is a well-known lipid-soluble potent antioxidant and antimutagenic compound formed in\u00a0canola oil via sinapic acid decarboxylation during oil\u00a0pressing at high temperature and pressure. The antiradical scavenging activity of canolol is much greater than\u00a0that of well-known antioxidants, including vitamin C, bcarotene, a-tocopherol, rutin and quercetin. Unluckily,\u00a0canolol is almost completely lost during oil refining which advocates its isolation from meal and adding it\u00a0back to the oil. The lipophilic characteristics of canolol\u00a0might account for its high affinity to the cell membranes\u00a0and other biological membranes and hence its reactivity\u00a0inside the body where water-soluble antioxidants are hard\u00a0to react, thus establishing its outstanding role. The industrial demand of vinyl\u00a0phenols and canolol is relatively\u00a0satisfied by chemical synthesis and not from natural sources. Investigations have explored large scale synthesis of\u00a04-vinylphenols through microbial or chemical decarboxylation of cinnamic acids such as p-coumaric acid, ferulic\u00a0acid, sinapic acid and caffeic acid from plant sources\u00a0including barley, wheat bran and sunflower seeds.<\/p>\n

Investigations to obtain this bioactive compound from\u00a0the natural sources are rare and not really successful.\u00a0Although many attempts were tried, the amounts obtained\u00a0from this compound from either natural sources or chemical synthesis were not able to meet the ever-increasing\u00a0industrial demand due to the limited amount of this\u00a0compound in plant sources and the less yield and high cost in\u00a0the chemical synthesis. Consequently, there is a growing\u00a0interest in developing alternative natural sources and more\u00a0economic procedures to obtain this phenol in significant\u00a0amounts to fulfill the industry demand.<\/p>\n

This paper reports a new procedure for the production of\u00a0canolol from under-utilized canola meal through a\u00a0sequence of alkaline\/enzymatic hydrolysis followed by\u00a0decarboxylation of the hydrolyzed substrates under\u00a0microwave irradiation. The conversion of sinapine and\u00a0other sinapic acid derivatives to canolol will pave the way\u00a0for new and unlimited opportunities, especially for byproduct utilization, canola oil\u00a0refining and value-added\u00a0processing of canola meal.<\/p>\n

Alkaline Hydrolysis<\/p>\n

The phenolic extracts were hydrolyzed with NaOH to\u00a0release the esterified phenolics. When the pH was below 2,\u00a0the released phenolics were available as phenolic acids\u00a0instead of ionic forms and could be extracted with diethyl\u00a0ether\/ethyl acetate mixture. Insoluble-bound\u00a0phenolics were not extractable using the normal common\u00a0extraction procedures and potentially retained in the meal.\u00a0Their proportion is small, but they can be released from\u00a0canola by alkaline hydrolysis. As sinapine, the choline\u00a0ester of sinapic acid, is the major phenolic compound in\u00a0canola meal extracts, the major role of the alkaline treatment is to break the ester linkage in sinapine thereby liberating sinapic acid and choline. The released\u00a0phenolics were extracted with either diethyl ether, or ethyl\u00a0acetate, or both. The conversion efficiency and the yield\u00a0obtained were\u00a0higher with alkaline hydrolysis compared to\u00a0other methods including enzyme hydrolysis. Alkaline\u00a0hydrolysis was conducted on the methanolic extracts as\u00a0well as on the meal itself. Sinapine was the predominant\u00a0phenolic compound in rapeseed meal, while the amount of\u00a0sinapic acid was considerably less. Concerning the methanolic extracts, the total phenolic content was\u00a010.6 \u00b1 0.01 mg\/g meal (sinapic acid equivalents; SAEs)\u00a0estimated using the HPLC analysis from the total area\u00a0under all peaks. The results are in accordance\u00a0with previous work. After hydrolysis, it ranged\u00a0from 8.1 to 11.0 mg\/g reaching its highest value after\u00a0hydrolyzing for 2 h using 20 mL of 4 M NaOH for 20 mL\u00a0of the extract. The amount of released sinapic acid showed\u00a0how efficient different hydrolyzing conditions were in\u00a0releasing sinapic acid from its esters. Hydrolysis is considered complete if the value of released sinapic acid is\u00a0100 % of the total phenolic content in the original extract.\u00a0Under optimum conditions all phenolics were hydrolyzed\u00a0to sinapic acid which increased from 0.14 to 10.2 mg\/g\u00a0representing 94.8 % of the total phenolic content in the\u00a0original extract.
\nUsing canola meal as a substrate for alkaline hydrolysis,\u00a0the released sinapic acid content was lower compared to\u00a0using the methanolic extracts. The original meal\u00a0contained 6.8, 1.1, 0.3 and 8.5 mg\/g sinapine, sinapoyl\u00a0glucose, sinapic acid and total phenolics, respectively.\u00a0After hydrolysis, the released sinapic acid content was\u00a07.1 mg\/g (81.0 and 93.9 % of the total phenolics in the\u00a0original and hydrolyzed meal, respectively).<\/p>\n

 <\/p>\n

 <\/p>\n

Reference\uff1a<\/p>\n

Rabie Y. Khattab \u2022 Michael N. A. Eskin \u2022\u00a0Usha Thiyam-Hollander. J Am Oil Chem Soc (2014) 91:89\u201397<\/p>\n

<\/h4>\n

Related\u00a0Products:<\/h4>\n
<\/div>
<\/th><\/th><\/th><\/th><\/tr><\/thead>
CAS Number <\/td>Product Name <\/td>Molecular Formula <\/td>Molecular Weight <\/td><\/tr>
121-79-9 <\/td>Propyl Gallate<\/a><\/td>C10H12O5 <\/td>212.20 <\/td><\/tr>
1948-33-0 <\/td>tert-Butylhydroquinone<\/a><\/td>C10H14O2 <\/td>166.22 <\/td><\/tr>
25013-16-5 <\/td>Butylated hydroxyanisole<\/a><\/td>C11H16O2 <\/td>180.25 <\/td><\/tr>
128-37-0 <\/td>butylhydroxytoluene<\/a><\/td>C15H24O <\/td>220.35 <\/td><\/tr>
28343-22-8 <\/td>Canolol<\/a><\/td>C10H12O3 <\/td>180.20 <\/td><\/tr><\/tbody><\/table><\/div>\n","protected":false},"excerpt":{"rendered":"

Free radicals induce oxidative damage in vivo causing\u00a0aging and various diseases. They are also the major\u00a0cause for deterioration, quality loss, and shelf life reduction\u00a0in oils\/fats and fat-containing systems. There are […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[181],"tags":[214,301,302,307,300,309,304],"_links":{"self":[{"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/posts\/511"}],"collection":[{"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/comments?post=511"}],"version-history":[{"count":1,"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/posts\/511\/revisions"}],"predecessor-version":[{"id":512,"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/posts\/511\/revisions\/512"}],"wp:attachment":[{"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/media?parent=511"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/categories?post=511"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/tags?post=511"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}