{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,24]],"date-time":"2025-10-24T20:59:11Z","timestamp":1761339551128,"version":"build-2065373602"},"reference-count":38,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2016,1,13]],"date-time":"2016-01-13T00:00:00Z","timestamp":1452643200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Anaerobic digestion using mixed-culture with broader choice of pretreatments for hydrogen (H2) production was investigated. Pretreatment of wastewater sludge by five methods, such as heat, acid, base, microwave and chloroform was conducted using crude glycerol (CG) as substrate. Results for heat treatment (100 \u00b0C for 15 min) showed the highest H2 production across the pretreatment methods with 15.18 \u00b1 0.26 mmol\/L of medium at 30 \u00b0C in absence of complex media and nutrient solution. The heat-pretreated inoculum eliminated H2 consuming bacteria and produced twice as much as H2 as compared to other pretreatment methods. The fermentation conditions, such as CG concentration (1.23 to 24 g\/L), percentage of inoculum size (InS) (1.23% to 24% v\/v) along with initial pH (2.98 to 8.02) was tested using central composite design (CCD) with H2 production as response parameter. The maximum H2 production of 29.43 \u00b1 0.71 mmol\/L obtained at optimum conditions of 20 g\/L CG, 20% InS and pH 7. Symbiotic correlation of pH over CG and InS had a significant (p-value: 0.0011) contribution to H2 production. The mixed-culture possessed better natural acclimatization activity for degrading CG, at substrate inhibition concentration and provided efficient inoculum conditions in comparison to mono- and co-culture systems. The heat pretreatment step used across mixed-culture system is simple, cheap and industrially applicable in comparison to mono-\/co-culture systems for H2 production.<\/jats:p>","DOI":"10.3390\/ijms17010092","type":"journal-article","created":{"date-parts":[[2016,1,13]],"date-time":"2016-01-13T22:19:54Z","timestamp":1452723594000},"page":"92","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Enrichment of Secondary Wastewater Sludge for Production of Hydrogen from Crude Glycerol and Comparative Evaluation of Mono-, Co- and Mixed-Culture Systems"],"prefix":"10.3390","volume":"17","author":[{"given":"Vinayak","family":"Pachapur","sequence":"first","affiliation":[{"name":"Centre-Eau Terre Environnement, 490, Institut National de la Recherche Scientifique, Rue de la Couronne, Qu\u00e9bec, QC G1K 9A9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Prianka","family":"Kutty","sequence":"additional","affiliation":[{"name":"Department of Biotechnology, National Institute of Technology Warangal, Warangal, Telangana 506004, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Satinder","family":"Brar","sequence":"additional","affiliation":[{"name":"Centre-Eau Terre Environnement, 490, Institut National de la Recherche Scientifique, Rue de la Couronne, Qu\u00e9bec, QC G1K 9A9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonio","family":"Ramirez","sequence":"additional","affiliation":[{"name":"Centre National en \u00c9lectrochimie et en Technologies Environnementales, 2263, Avenue du Coll\u00e8ge, Shawinigan, QC G9N 6V8, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,1,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1319","DOI":"10.1016\/j.ijhydene.2012.11.069","article-title":"Enrichment of activated sludge for enhanced hydrogen production from crude glycerol","volume":"38","author":"Varrone","year":"2013","journal-title":"Int. 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