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Recently, attention has been given to nanocellulose produced by bacteria due to its unique properties and environmentally friendly nature when compared with plant cellulose. Bacterial nanocellulose (BNC) producing isolate was successfully isolated from rotten fruits via dilution and spread plates method. Based on the biochemical characterisation and molecular analysis of the 16S rDNA gene, the isolate was identified as Gluconacetobacter xylinus BCMZ sp. Nanocellulose productivity was confirmed by the formation of the white gelatinous layer between air/liquid surfaces when the culture was cultivated under a stationary condition at 30°C. Successful purification of nanocellulose was achieved using alkaline treatment method. The Fourier transformed infrared spectrum showed a characteristics band signature of pure nanocellulose, by displaying strong absorption peaks at 3335.36 and 2901.40 cm −1 representing carbonyl and carbon-hydrogen bonding, respectively. Morphological characteristics of the BNC were determined by scanning electron microscopy (SEM). Elemental analysis of BNC was determined by energy dispersive X-ray (SEM/EDX) analysis. The isolates BCZM showed significant nanocellulose production ability with a high degree of purity when compared with plant nanocellulose. BNC purification using 1 M NaOH solution is effective and eco-friendly with no indication of recalcitrant formation as commonly found in plant nanocellulose purification steps.

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Sanitary landfilling is the most common way to dispose solid urban waste; however, improper landfill management may pose serious environmental threats through discharge of high strength polluted wastewater also known as leachate. The treatment of landfill leachate to fully reduce the negative impact on the environment, is nowadays a challenge. In this study, an aerobic sequencing batch reactor (ASBR) was proposed for the treatment of locally obtained real landfill leachate with initial ammoniacal nitrogen and chemical oxygen demand (COD) concentration of 1800 and 3200 mg/L, respectively. ASBR could remove 65 % of ammoniacal nitrogen and 30 % of COD during seven days of treatment time. Thereafter, an effective adsorbent, i.e., zeolite was used as a secondary treatment step for polishing the ammoniacal nitrogen and COD content that is present in leachate. The results obtained are promising where the adsorption of leachate by zeolite further enhanced the removal of ammoniacal nitrogen and COD up to 96 and 43 %, respectively. Furthermore, this combined biological–physical treatment system was able to remove heavy metals, i.e. aluminium, vanadium, chromium, magnesium, cuprum and plumbum significantly. These results demonstrate that combined ASBR and zeolite adsorption is a feasible technique for the treatment of landfill leachate, even considering this effluent’s high resistance to treatment.