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  • post print Purification and polymerisation of microbial d-lactic acid from DDGS hydrolysates fermentation

    Accepted author manuscript, 1 MB, PDF document

    Embargo ends: 15/06/21

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A multi-step process was developed for microbial d-lactic acid purification, followed by poly-d-lactic acid (PDLA) synthesis via azeotropic polycondensation process. Several anion exchange resins were screened for their binding capacity using model lactic acid solutions. Amberlite® IRA67 (weak base anion exchange resin) showed the highest lactic acid adsorption, with maximum adsorption capacity, qmax, of 136.11 mg lactic acid / g of resin, and was further selected to purify D-lactic acid from DDGS hydrolysates through a three-step process; (1) treatment with 7% w/v activated carbon, (2) acidification of fermentation broth (Amberlite® IRA120) and (3) adsorption of lactic acid by anion exchange (Amberlite® IRA67). At the end of the purification process, 80.4% (w/w) D-lactic acid was recovered with 91.8% (w/w) purity, indicating the effectiveness of the developed downstream process. Furthermore, a clear yellowish solid polymer with a molecular weight of 3010 Da was obtained, suitable for applications in biomedical and agricultural sectors.
Original languageEnglish
Article number107265
JournalBiochemical Engineering Journal
Early online date15 Jun 2019
Publication statusPublished - 15 Oct 2019
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