{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T15:55:54Z","timestamp":1791302154712,"version":"4.1.0"},"reference-count":51,"publisher":"American Chemical Society (ACS)","issue":"39","license":[{"start":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T00:00:00Z","timestamp":1790121600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,10,6]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Intensive use of mineral fertilizers has reduced natural soil fertility and increased the demand for sustainable nutrient sources. In this study, three digestates obtained from Lithuanian biogas plants were chemically and instrumentally characterized and evaluated as potential sources of organic carbon and plant nutrients. The dried digestates contained 52.9\u201359.5% organic carbon and appreciable amounts of nitrogen, phosphorus, and potassium, although the measured nutrient concentrations depended on the applied extraction or mineralization procedure. The influence of key extraction parameters, including extractant type (water or 0.5 M KOH), temperature, extraction time, particle size, and extraction method (magnetic stirring or ultrasonication), on organic carbon recovery was systematically investigated. Alkaline extraction markedly increased TOC concentrations in the extracts, yielding values up to approximately 8\u201329 times higher than those obtained by aqueous extraction after 3 days. The highest TOC concentration (4495 mg\/L) was obtained for KP digestate extracted with 0.5 M KOH at 90 \u00b0C using magnetic stirring for 6 h. In aqueous extracts, the maximum TOC concentration reached 715 mg\/L under ultrasonication at 50 \u00b0C. Temperature, extraction time, and particle size had condition- and digestate-dependent effects on TOC recovery. The ultrasonic extraction series yielded the highest TOC concentration among the aqueous extracts, whereas the magnetic-stirring series yielded the highest value under alkaline conditions. In addition, carbon recovery efficiency was calculated relative to the initial organic carbon content of the digestates, providing a quantitative assessment of carbon transfer from the solid material to the liquid phase. The highest carbon recovery efficiency reached approximately 76%. These results identify the extraction conditions that enhance soluble organic carbon recovery from digestate and provide a basis for further chemical characterization and application-oriented evaluation of the obtained extracts.<\/jats:p>","DOI":"10.1021\/acsomega.6c04180","type":"journal-article","created":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T03:02:10Z","timestamp":1790218930000},"page":"58979-58995","source":"Crossref","is-referenced-by-count":0,"title":["Influence of Extraction\nConditions on Organic Carbon\nRecovery from Biogas Digestate"],"prefix":"10.1021","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-2595-0739","authenticated-orcid":true,"given":"Egle\u0307","family":"Didz\u030ciulyte\u0307","sequence":"first","affiliation":[{"name":"Kaunas University of Technology ,","place":["Kaunas, Lithuania, 50254"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rasa","family":"S\u030clinks\u030ciene\u0307","sequence":"additional","affiliation":[{"name":"Kaunas University of Technology ,","place":["Kaunas, Lithuania, 50254"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,9,23]]},"reference":[{"key":"2026100610473508300_cit1","doi-asserted-by":"publisher","first-page":"544","DOI":"10.1038\/s43017-020-0080-8","article-title":"The Concept\nand Future Prospects of Soil Health","volume":"1","author":"Lehmann","year":"2020","journal-title":"Nat. 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Biorefin."},{"issue":"12","key":"2026100610473508300_cit38","doi-asserted-by":"publisher","first-page":"3161","DOI":"10.3390\/en13123161","article-title":"Waste to Energy:\nSolid Fuel Production from Biogas Plant Digestate and Sewage Sludge\nby Torrefaction -Process Kinetics, Fuel Properties, and Energy Balance","volume":"13","author":"Swiechowski","year":"2020","journal-title":"Energies"},{"key":"2026100610473508300_cit39","doi-asserted-by":"publisher","first-page":"1657","DOI":"10.3390\/molecules24091657","article-title":"Kinetic Analysis of\nDigestate Slow Pyrolysis with the\nApplication of the Master-Plots Method and Independent Parallel Reaction\nScheme","volume":"24","author":"Bartocci","year":"2019","journal-title":"Molecules"},{"issue":"6","key":"2026100610473508300_cit40","doi-asserted-by":"publisher","first-page":"1728","DOI":"10.1002\/bbb.2772","article-title":"A Novel Treatment\nof Biogas Digestate\nWaste for Biochar Production and Its Adsorption of Methylene Blue\nand Malachite Green in a Binary System","volume":"19","author":"Duong","year":"2025","journal-title":"Biofuels\nBioprod Bioref."},{"key":"2026100610473508300_cit41","doi-asserted-by":"publisher","first-page":"112129","DOI":"10.1016\/j.jece.2024.112129","article-title":"Assessment of the Effectiveness of\nProcess-Induced Struvite Crystallization Process on the Recovery of\nNutrients from High-Strength Liquid Digestate of an Anaerobic Biogas\nPlant","volume":"12","author":"Yazici","year":"2024","journal-title":"J. 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Sonochem."},{"key":"2026100610473508300_cit49","doi-asserted-by":"publisher","first-page":"687434","DOI":"10.3389\/fpls.2021.687434","article-title":"Evaluating\nthe Aqueous Phase From Hydrothermal Carbonization of Cow Manure Digestate\nas Possible Fertilizer Solution for Plant Growth","volume":"12","author":"Celletti","year":"2021","journal-title":"Front. Plant Sci."},{"issue":"3","key":"2026100610473508300_cit50","doi-asserted-by":"publisher","first-page":"78","DOI":"10.3390\/soilsystems9030078","article-title":"Factors Influencing the Impact of Anaerobic Digestates\non Soil Properties","volume":"9","author":"Ragalyi","year":"2025","journal-title":"Soil Syst."},{"issue":"7","key":"2026100610473508300_cit51","doi-asserted-by":"publisher","first-page":"1485","DOI":"10.1021\/acs.jced.3c00040","article-title":"Critical\nAnalysis of Published Physical Property Data for Aqueous Potassium\nHydroxide. 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