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The work is aimed to investigate the suitability of underutilized coffee cherry husk (CCH) for the production and optimization of bacterial cellulose (BC) by Gluconacetobacter hansenii UAC09 and to study the physico-mechanical properties of BC films. CCH extract was used as a carbon source in various concentrations along with other nutritional components such as nitrogen (corn steep liquor, urea) and additives (ethyl alcohol, acetic acid). Concentration of CCH extract at 1:1 (w/v) along with 8% (v/v) corn steep liquor, 0.2% (w/v) urea, combination of 1.5% ethyl alcohol and 1.0% (v/v) acetic acid resulted in the production of 5.6-8.2 g/L of BC. BC had tensile strength varying between 28.5 and 42.4 MPa. BC produced with CCH and Hestrin and Schramm (HS) media did not differ in structure as analyzed by FT-IR. Scanning electron microscopic studies indicated BC to contain reticulated network of fine fibers. Under optimized condition, based on the other additives, CCH produced more than three folds yield of BC (5.6-8.2 g/L) than control medium (1.5 g/L). This is the first report on the use of CCH for the production of BC and paved way for the utilization of organic wastes with pectin and high polyphenol content.

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During the production of grape wine, the occurrence of thick leathery pellicle at the air‐liquid interface was found as a contaminant. The pellicle produced was investigated with a view to use as biodegradable polymer. The bacterium that is responsible for the pellicle production was isolated, characterized and identified as Gluconacetobacter sp. Pellicle was produced in pasteurized grape extract as well as in HS medium by the isolated organism in static conditions. The purified film was subjected for Fourier transform infrared spectroscopy and C13 solid NMR spectroscopy analysis, which confirmed the pellicle to be a cellulosic material. Scanning Electron Micrograph showed ultra fine network structure along with cells. The films were tested for its physicomechanical characters, barrier and thermal properties. The films of 25‐μ thickness showed very high tensile strength (41.158 MPa) and elongation of 0.987 mm. The thermal properties of the films were characterized by Differential scanning calorimetry and Thermo gravimetric analysis. The melt peak temperature was found to be 111.65°C. The percentage of weight loss was found to be 20% at 327.86°C. Barrier properties (oxygen transmission rate and water vapor transmission rate), indicated a high oxygen barrier but low water barrier. This is the first report on the barrier properties of bacterial cellulose from Gluconacetobacter sp. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011