Kinetics of lipase-catalysed methyl gallate production in the presence of deep eutectic solvent

Ulger C., Takac S.

BIOCATALYSIS AND BIOTRANSFORMATION, cilt.35, sa.6, ss.407-416, 2017 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 35 Sayı: 6
  • Basım Tarihi: 2017
  • Doi Numarası: 10.1080/10242422.2017.1359573
  • Dergi Adı: BIOCATALYSIS AND BIOTRANSFORMATION
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.407-416
  • Anahtar Kelimeler: Choline chloride, deep eutectic solvent, methyl gallate, Novozym 435, propyl gallate transesterification, RESPONSE-SURFACE METHODOLOGY, ACID PHENETHYL ESTER, ENZYMATIC-SYNTHESIS, GALLIC ACID, PHENOLIC-ACIDS, PROPYL GALLATE, IONIC LIQUIDS, ORGANIC MEDIA, ALKYL ESTERS, FREE SYSTEM
  • Ankara Üniversitesi Adresli: Evet

Özet

Production of methyl gallate (MG), which is an important phenolic acid ester for pharmaceutical industry, was carried out by Novozym 435-catalysed transesterification of propyl gallate (PG) with methanol in a deep eutectic solvent. Reaction parameters governing substrate molar ratio, enzyme concentration, temperature and agitation rate were investigated batch-wise in choline chloride: glycerol-water binary mixture. The results were evaluated in terms of conversion of PG, yield of MG and hydrolysis of PG to gallic acid. 10% (w/w) of water was found to be favourable in the reaction medium for low hydrolysis percent. The highest conversion (17.4%) and yield (60.4%) but the lowest hydrolysis (2%) after 120 h of transesterification were found at PG/methanol molar ratio of 1:6, enzyme concentration of 40 g/L, 50 degrees C and 200 rpm. A kinetic model based on the Ping-Pong Bi-Bi mechanism for transesterification of PG was proposed with the assumption that there were no internal and external mass transfer resistances.