title: Can green solvents be alternatives for thermal stabilization of collagen?
abstract: "Go Green" campaign is gaining light for various industrial applications where water consumption needs to be reduced. To resolve this, industries have adopted usage of green, organic solvents, as an alternative to water. For leather making, tanning industry consumes gallons of water. Therefore, for adopting green solvents in leather making, it is necessary to evaluate its influence on type I collagen, the major protein present in the skin matrix. The thermal stability of collagen from rat tail tendon fiber (RTT) treated with seven green solvents namely, ethanol, ethyl lactate, ethyl acetate, propylene carbonate, propylene glycol, polyethylene glycol-200 and heptane was determined using differential scanning calorimetry (DSC). Crosslinking efficiency of basic chromium sulfate and wattle on RTT in green solvents was determined. DSC thermograms show increase in thermal stability of RTT collagen against heat with green solvents (>78°C) compared to water (63°C). In the presence of crosslinkers, RTT demonstrated thermal stability >100°C in some green solvents, resulting in increased intermolecular forces between collagen, solvent and crosslinkers. The significant improvement in thermal stability of collagen potentiates the capability of green solvents as an alternative for water.
authors.affiliation: Chemical Laboratory, CSIR-Central Leather Research Institute, Sardar Patel Road, Adyar, Chennai 600020, India.
authors.forename: Ami
authors.initials: A
authors.lastname: Mehta
authors.affiliation: Chemical Laboratory, CSIR-Central Leather Research Institute, Sardar Patel Road, Adyar, Chennai 600020, India.
authors.forename: J Raghava
authors.initials: JR
authors.lastname: Rao
authors.affiliation: Chemical Laboratory, CSIR-Central Leather Research Institute, Sardar Patel Road, Adyar, Chennai 600020, India. Electronic address: nishad@clri.res.in.
authors.forename: Nishter Nishad
authors.initials: NN
authors.lastname: Fathima
mesh_terms: D000818:Animals; D017608:Chromium Compounds / Q000494:pharmacology; D003094:Collagen / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000494:pharmacology; D055772:Green Chemistry Technology; D055550:Protein Stability / Q000187:drug effects; D051381:Rats; D012997:Solvents / Q000494:pharmacology*; D013431:Sulfates / Q000494:pharmacology; D013696:Temperature; D014867:Water / Q000494:pharmacology
chemical_list: D017608:Chromium Compounds; D003432:Cross-Linking Reagents; D012997:Solvents; D013431:Sulfates; D014867:Water; C040874:chromium sulfate; D003094:Collagen
keywords: Activation energy; Collagen; Differential scanning calorimetry; Green solvents; Thermal stability