Microwave-assisted extraction of pectin from orange peel using deep eutectic solvents


Turan O., İşci Yakan A., Yılmaz M. S., Tolun A., Şakıyan Demirkol Ö.

SUSTAINABLE CHEMISTRY AND PHARMACY, cilt.37, 2024 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 37
  • Basım Tarihi: 2024
  • Doi Numarası: 10.1016/j.scp.2023.101352
  • Dergi Adı: SUSTAINABLE CHEMISTRY AND PHARMACY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Anahtar Kelimeler: Deep eutectic solvents, Maceration, Microwave, Orange peel, Pectin
  • Ankara Üniversitesi Adresli: Evet

Özet

Pectin is a polysaccharide which is utilized in food, pharmaceutical and other industries. The commercial production of pectin involves mineral acids with high environmental impacts. Non conventional green solvents such as deep eutectic solvents could potentially reduce the environmental threats of the traditional method and make the pectin extraction more sustainable and eco-friendly. In this study, pectin is extracted using maceration and microwave-assisted deep eutectic solvent (MW-DES) methods from orange peel under variable operating conditions. Process conditions had positive impact on pectin containing extract yields. The best conditions consisted of choline chloride:formic acid concentration of 8 % (v/v), an extraction time of 15 min and microwave power of 360 W for MW-DES. The maximum yields were 46 and 40% for maceration and MW-DES extraction, respectively. Microwave assistance decreased the extraction time by 75% compared to maceration method. The pectin samples extracted using DES were high methoxyl type with a degree of esterification of 85.6 and 74.4% for Maceration-DES and MW DES, respectively. The galacturonic acid and total sugar contents were found statistically same for both methods. In addition, a significantly lower galacturonic acid content was observed in DES extracts compared to that of commercial and conventional pectin, indicating the need for advanced purification steps after DES extraction. MW-DES pectin had better water holding capacity and higher viscosity compared to that of Maceration-DES. Moreover, total phenolic content of the pectin samples were found as 8.19 and 7.14 mg Gallic acid equivalent/g of sample for maceration and MW-DES methods, respectively. The findings suggest that MW-DES could be an effective and fast extraction method for pectin from orange peels. However, further research is required to determine the energy consumption and to optimize extraction conditions.