{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T03:50:03Z","timestamp":1790567403697,"version":"4.1.0"},"reference-count":42,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,6,6]],"date-time":"2023-06-06T00:00:00Z","timestamp":1686009600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Research, Innovation and Digitization, CNCNS-UEFISCDI","award":["PN-III-P1.1.1-TE-2021-0179"],"award-info":[{"award-number":["PN-III-P1.1.1-TE-2021-0179"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>L-polylactic acid (PLA), a semi\u2013crystalline aliphatic polyester, is one of the most manufactured biodegradable plastics worldwide. The objective of the study was to obtain L-polylactic acid (PLA) from lignocellulosic plum biomass. Initially, the biomass was processed via pressurized hot water pretreatment at a temperature of 180 \u00b0C for 30 min at 10 MPa for carbohydrate separation. Cellulase and the beta-glucosidase enzymes were then added, and the mixture was fermented with Lacticaseibacillus rhamnosus ATCC 7469. The resulting lactic acid was concentrated and purified after ammonium sulphate and n-butanol extraction. The productivity of L-lactic acid was 2.04 \u00b1 0.18 g\/L\/h. Then, the PLA was synthesized in two stages. Firstly, lactic acid was subjected to azeotropic dehydration at 140 \u00b0C for 24 h in the presence of xylene, using SnCl2 (0.4 wt.%) as a catalyst, resulting in lactide (CPLA). Secondly, microwave-assisted polymerization was carried out at 140 \u00b0C for 30 min with 0.4 wt.% SnCl2. The resulting powder was purified with methanol to produce PLA with 92.1% yield. The obtained PLA was confirmed using electrospray ionization mass spectrometry, nuclear magnetic resonance, thermogravimetric analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction. Overall, the resulting PLA can successfully replace the traditional synthetic polymers used in the packaging industry.<\/jats:p>","DOI":"10.3390\/ijms24129817","type":"journal-article","created":{"date-parts":[[2023,6,7]],"date-time":"2023-06-07T02:28:45Z","timestamp":1686104925000},"page":"9817","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["L-Poly(lactic acid) Production by Microwave Irradiation of Lactic Acid Obtained from Lignocellulosic Wastes"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5791-0449","authenticated-orcid":false,"given":"Lacrimioara","family":"Senila","sequence":"first","affiliation":[{"name":"Research Institute for Analytical Instrumentation Subsidiary, National Institute for Research and Development of Optoelectronics Bucharest INOE 2000, 67 Donath Street, 400293 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0879-9211","authenticated-orcid":false,"given":"Oana","family":"Cadar","sequence":"additional","affiliation":[{"name":"Research Institute for Analytical Instrumentation Subsidiary, National Institute for Research and Development of Optoelectronics Bucharest INOE 2000, 67 Donath Street, 400293 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1970-0923","authenticated-orcid":false,"given":"Eniko","family":"Kovacs","sequence":"additional","affiliation":[{"name":"Research Institute for Analytical Instrumentation Subsidiary, National Institute for Research and Development of Optoelectronics Bucharest INOE 2000, 67 Donath Street, 400293 Cluj-Napoca, Romania"},{"name":"Faculty of Horticulture, University of Agricultural Sciences and Veterinary Medicine, 3-5 Manastur Street, 400372 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4324-0787","authenticated-orcid":false,"given":"Emese","family":"Gal","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University, 11 Arany Janos Street, 400028 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Monica","family":"Dan","sequence":"additional","affiliation":[{"name":"National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donath Street, 400293 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zamfira","family":"Stupar","sequence":"additional","affiliation":[{"name":"Research Institute for Analytical Instrumentation Subsidiary, National Institute for Research and Development of Optoelectronics Bucharest INOE 2000, 67 Donath Street, 400293 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4914-6986","authenticated-orcid":false,"given":"Dorina","family":"Simedru","sequence":"additional","affiliation":[{"name":"Research Institute for Analytical Instrumentation Subsidiary, National Institute for Research and Development of Optoelectronics Bucharest INOE 2000, 67 Donath Street, 400293 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6738-6356","authenticated-orcid":false,"given":"Marin","family":"Senila","sequence":"additional","affiliation":[{"name":"Research Institute for Analytical Instrumentation Subsidiary, National Institute for Research and Development of Optoelectronics Bucharest INOE 2000, 67 Donath Street, 400293 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cecilia","family":"Roman","sequence":"additional","affiliation":[{"name":"Research Institute for Analytical Instrumentation Subsidiary, National Institute for Research and Development of Optoelectronics Bucharest INOE 2000, 67 Donath Street, 400293 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"136815","DOI":"10.1016\/j.jclepro.2023.136815","article-title":"Lignocellulosic biomass from agricultural waste to the circular economy: A review with focus on biofuels, biocomposites and bioplastics","volume":"402","author":"Mujtaba","year":"2023","journal-title":"J. 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