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Tannery waste–based gelatin composite film reinforced with cellulose II nanocrystal (CNC II) extracted from wet wipes using three different hydrolysis techniques is explored for its functional properties and possible utilization as a biodegradable packaging material. CNC II isolated using hydrogen peroxide (PCNC), citric acid (CCNC), and hydrochloric acid (HCNC) differed in morphological and crystalline character as investigated using DLS, FE-SEM, FTIR, and XRD analysis. The crystallinity of PCNC, CCNC, and HCNC was found to be 81.1%, 75.4%, and 86.1%, respectively. The highly crystalline CNC II (PCNC) incorporation improved mechanical stiffness of rawhide trimming waste–based gelatin films by 50% compared to control gelatin film. Maximum thermal decomposition with T max of 329 °C was obtained for gelatin films with PCNC nano-reinforcement. Films with CNC II were structurally stable and sufficiently antibacterial against Gram-positive S. aureus microbial strain. Strong interfacial non-covalent and hydrogen bonding interactions between gelatin and cellulose II nanocrystal have likely enhanced the properties of the composite films. Incorporation of CNC II reduced the surface wettability of the films and nanocomposites absorbed UV radiation as evidenced by transmittance value T 280 of 0.19%. Nanocomposite films degraded up to 79.9% of initial mass within 7 days of soil burial. Furthermore, based on the optimized system, single-use packaging application of eggplant seeds has been demonstrated. Graphical abstract

Leather manufacturing is one of the industrial activities, contribute significantly to economy and employment. Chromium being a carcinogen, the discharge of chrome tanning wastewater is associated with serious health hazards and significant negative environmental impacts. The present research deals with the recovery and reuse of chrome tanning effluent by mineralizing the organic contaminants present in the chrome tanning wastewater through electro-oxidation technique. The EO process was carried out by using titanium as anode for 120 min with variation in current density (3.0 V; 12 A and 4.0 V; 15 A). COD and TOC were found to decrease gradually with respect to time. The treated chrome liquor was then subjected to the reduction reaction using sodium metabisulfite so as to reduce the hexavalent chromium, to trivalent state. The leather produced using the recovered chrome liquor along with fresh chrome tanning agent was found to have good hydrothermal stability and adequate chromium content. This method of treating tanning effluent is an economically viable and environment-friendly alternative method for avoiding the disposal of chrome effluent.

The objective of the study was to investigate the potential dye degrading fungal species from textile mill effluents in a cost effective and eco friendly manner. Decolorizing isolates of Zygomycotina, Deuteromycotina and Ascomycetes were isolated from dye industry effluents. Decolorization assay was carried out on both solid and liquid assay medium along with laccase activity. Among all the fungi, Aspergillus was a dominant species recorded among the effluents. All the fungal isolates were tested for decolorizing activity against methylene blue, crystal violet, sudan black, malachite green and methyl red. On solid and liquid medium, Aspergillus terreus, A.niger, and Fusarium moniliforme were found to decolorize maximum number of dyes and registered maximum percentage of color reduction. Laccase assay was done using Lignin modifying enzyme basal medium with Hydroxybenzotriazole, and among the isolates, F. moniliforme and A. terreus were found to produce the laccase enzyme. Among the 13 species of fungal isolates, the maximum degradation activity was shown by A. terreus (86.33 %), followed by A. niger (84.20) and F. moniliforme (80.00 %) seems to be potential candidates to degrade commonly used dyes. So these strains can be used for treating the dye containing effluents as well as in bio remediating degraded aquatic and land polluted by these effluents. So, commercial development and application of this fungus for textile wastewater treatment will be an advantage to dye removal process.