title: Biosurfactants from urban green waste.
abstract: From waste came forth surfactants: Humic acid like substances isolated from 0-60 day-old compost display excellent surface activity and solvent properties. These biosurfactants were used to solubilize a dye in water below and above their critical micellar concentration. The biosurfactant unimers appear to have higher dye-solubilizing power than the corresponding micelles.Humic acid like substances isolated from compost show potential as chemical auxiliaries. In the present study, three surfactant samples were obtained from green waste composted for 0-60 days to assess aging effects of the source on the properties of the products. The surface activity, dye solubility enhancement, and chemical nature of these substances were compared. No differences in performance were established among the samples. They lower water surface tension and enhance the dye solubility upon increasing their concentration. However, the ratio of soluble dye to added surfactant is higher in the premicellar than in the postmicellar concentration region. Structural investigations indicated the humic acid like substances to be amphiphiles with molecular weights in the range of 1-3 x 10(5) g mol(-1). The surfactant samples were also compared to sodium dodecylbenzenesulfonate, polyacrylic acid, and soil and water humic substances. The results encourage the application of compost as a source of low-cost biosurfactant.
authors.affiliation: Dipartimento di Chimica Generale e Chimica Organica, Università di Torino, Corso Massimo d'Azeglio 48, Turin, Italy. enzo.montoneri@unito.it
authors.forename: Enzo
authors.initials: E
authors.lastname: Montoneri
authors.forename: Vittorio
authors.initials: V
authors.lastname: Boffa
authors.forename: Piero
authors.initials: P
authors.lastname: Savarino
authors.forename: Daniele G
authors.initials: DG
authors.lastname: Perrone
authors.forename: Giorgia
authors.initials: G
authors.lastname: Musso
authors.forename: Raniero
authors.initials: R
authors.lastname: Mendichi
authors.forename: Michele R
authors.initials: MR
authors.lastname: Chierotti
authors.forename: Roberto
authors.initials: R
authors.lastname: Gobetto
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D001557:Benzenesulfonates / Q000737:chemistry; D002947:Cities; D004396:Coloring Agents / Q000737:chemistry; D003247:Conservation of Natural Resources; D006812:Humic Substances; D008027:Light; D009682:Magnetic Resonance Spectroscopy; D008970:Molecular Weight; D012542:Scattering, Radiation; D012987:Soil; D012995:Solubility; D013500:Surface Tension; D013501:Surface-Active Agents / Q000737:chemistry*; D000099166:Polyacrylamides
chemical_list: D000180:Acrylic Resins; D001557:Benzenesulfonates; D004396:Coloring Agents; D006812:Humic Substances; D012987:Soil; D013501:Surface-Active Agents; D000099166:Polyacrylamides; C006903:carbopol 940; C001114:dodecylbenzenesulfonic acid