Cellulose Yield Research Articles

Utilization of Yam Bean Juice as Nutrient Source for Bacterial Cellulose Production by Komagataeibacter nataicola TISTR 975

Background: Bacterial cellulose has attracted much interest over the years because of its diverse applications stemming from its unique properties. Alternative sources of raw materials for culture medium have become essential to reduce the cost of raw materials and scale up bacterial cellulose production. Objectives: The present study aims to investigate the cellulose-producing ability and characteristics of bacterial cellulose produced by Komagataeibacter nataicola TISTR 975 using yam bean juice as a nutrient source and optimizing the culture medium conditions to produce bacterial cellulose. Methods: Bacterial cellulose was produced by K. nataicola TISTR 975 using yam bean juice as the nutrient source in the culture medium. Fermentation was performed in static culture using 10% inoculum, with varying levels of initial total soluble solids content (8, 10, and 12 °Brix), supplemented with ammonium sulfate (0.1, 0.3, and 0.5 (% w/v)), pH 5.0, 1.4% (v/v) ethanol, and incubated at 30 °C for 10 days. The cellulose membrane was measured for cellulose yield. Physicochemical and sensory characteristics of bacterial cellulose were examined. Results: Initial total soluble solids content at 10 °Brix (equal to the sugar content of approximately 100 g/L) and supplemented with 0.1% (w/v) of ammonium sulfate improved bacterial cellulose yield. Moisture content and water holding capacity (WHC) of bacterial cellulose were high, and L*, a*, and b* values and textural properties were related to perceived sensory characteristics. Sensory evaluation showed the highest score for color and overall acceptability. Conclusion: Local edible yam bean tubers could be used as an alternative raw material for bacterial cellulose production by K. nataicola TISTR 975 using yam bean juice, and bacterial cellulose produced using yam bean juice as a nutrient source has the sensory attributes consistent with the desirable characteristics of raw material for food and processed food products.

THE ISOLATION OF α-CELLULOSE & THE PREPARATION OF MICROCRYSTALLINE CELLULOSE FROM SOURSOP LEAVES (Annona muricata L.)

Powder characteristics are very important to consider in the tablet manufacturing process because they can affect the characteristics of the resulting tablets. This study aims to determine the characteristics of microcrystalline cellulose powder isolated from soursop leaves. This research method includes preparation of soursop leaves raw material, isolation of α-cellulose using 17.5% NaOH solution with 3.5% nitric acid (containing 20 mg sodium nitrite), manufacture of microcrystalline cellulose using 1 M HCl solution, and characterization of microcrystalline cellulose including quality checks. powder (organoleptic, identification, solubility), and pH testing. The results showed that the yield of microcrystalline cellulose (MCCDSr) was 96.59% against α-cellulose. The results of the characterization of microcrystalline cellulose powder including organoleptic, identification, solubility, melting point, and pH showed similar characteristics with Avicel® PH 101 as a comparison. Based on the research that has been done, the characteristics of microcrystalline cellulose powder from soursop leaves are similar to Avicel® PH 101.

Dinoflagellates as sustainable cellulose source: Cultivation, extraction, and characterization

The global demand for manufacturing and consuming biodegradable materials from natural sources has created a great interest in microalgae such as dinoflagellates. Photosynthetic dinoflagellates are a sustainable source of natural materials such as cellulose as they grow using only sunlight and CO2 at near-neutral pH without any fertilizers. In this paper, the cultivation of two species of dinoflagellates (Peridinium sp. and Prorocentrum micans) is established under lab conditions (up to 20 l), cellulose extraction is optimized, and the resulting material is thoroughly characterized. Dinoflagellate cellulose was extracted at room temperature by sequential treatment with highly concentrated 30 % NaOH and 6 M HCl, followed by bleaching with 10 % H2O2. The overall yield of cellulose is around 73 % (w/w), and roughly 85 % of the original dinoflagellate cellulosic morphology remains intact. Chemical purity, morphology, and porosity of the dinoflagellate-derived cellulose are analysed by different characterization techniques (ICP-OES, SEM, XRD, ATR-FTIR, Raman, ssNMR, TGA, BET, and GPC). XRD characterization of the extracted cellulose shows no characteristic reflexes corresponding to a cellulose II allomorph which is mainly amorphous. This result is further supported by ATR-FTIR, Raman, and ssNMR spectroscopy. Overall, these results show that the extracted cellulose is a highly porous, lignin-free material that is thermally stable up to 260 °C. Its high degree of purity and porosity make dinoflagellate-derived cellulose a promising, sustainable candidate for the development of functional hybrid materials for biomedical applications.

Genome-Wide Association Study (GWAS) of the Agronomic Traits and Phenolic Content in Sorghum (Sorghum bicolor L.) Genotypes

Sorghum (Sorghum bicolor L.) is a promising biomass crop with high yields of cellulose, hemicellulose, and lignin. Sorghum biomass has emerged as an eco-friendly industrial material useful for producing biofuels and bioplastics. This study conducted genotyping-by-sequencing (GBS)-based genome-wide association studies (GWAS) to establish the genetic basis of traits associated with biomass. Specifically, the researchers evaluated agronomic traits and phenolic compounds using 96 sorghum genotypes. Six phenolic compounds, luteolinidin diglucoside, luteolin glucoside, apigeninidin glucoside, luteolinidin, apigeninidin, and 5-O-Me luteolinidin, were found to be the major phenolic compounds in all genotypes. Out of our six detected phenolic compounds (luteolinidin diglucoside, luteolin glucoside, apigeninidin glucoside, luteolinidin, apigeninidin, and 5-O-Me luteolinidin), luteolinidin was the major phenolic compound in all genotypes. Next, a GWAS analysis was performed to confirm significant associations between 192,040 filtered single-nucleotide polymorphisms (SNPs) and biomass-related traits. The study identified 40 SNPs on 10 chromosomes that were significantly associated with heading date (4 SNPs), plant height (3 SNPs), dry yield (2 SNPs), and phenolic compounds (31 SNPs). The GWAS analysis showed that SbRio.10G099600 (FUT1) was associated with heading date, SbRio.09G149200 with plant height, SbRio.06G211400 (MAFB) with dry yield, SbRio.04G259800 (PDHA1) with total phenolic content and luteolinidin diglucoside, and SbRio.02G343600 (LeETR4) with total phenolic content and luteolinidin, suggesting that these genes could play key roles in sorghum. These findings demonstrate the potential value of sorghum as a biomass resource and the potential for selecting sorghum genotypes with reduced phenolic contents for use in the bioindustry.

Recent Advancements in the Valorization of Agro-Industrial Food Waste for the Production of Nanocellulose

The rising climate change concerns over the excessive exploitation of non-renewable sources have necessitated the need for alternative renewable and eco-friendly resources for the production of innovative materials, achieving the targets of bioeconomy. Lignocellulosic biomass (LB) constituted by polymeric sugars and lignin is an abundantly available plant-based renewable material in the form of agro-industrial food waste and crop residues that can be exploited for the production of an array of value-added chemicals and bioproducts. Cellulose is the most abundant natural and biodegradable organic polymer on earth derived from LB, with wide scale applications in the lignocellulosic biorefineries and food industries. The negative effects of food waste from agro-industrial activities could be reduced through the recovery of cellulose from these wastes and converting it into valuable forms. However, the extraction of cellulose from LB is a difficult task owing to the recalcitrant nature of biomass that restricts the easy accessibility of cellulose for value addition. Therefore, a suitable cellulose extraction method through the fractionation of LB is necessary for a better cellulose yield. Furthermore, owing to the enormous potential of nanocellulose (NC), researchers are keenly interested in developing ecologically acceptable cellulose extraction methods. Cellulose nanofibrils and nanocrystals confer excellent mechanical properties, non-toxic characteristics and biodegradability, due to which they possess wide-scale applications in diverse industrial sectors. The current review emphasizes the potential role of cellulose extraction and NC production from agro-food waste. The different pretreatment methods for their extraction from LB are outlined. The applications of nanocellulose in different areas are also discussed. The review also highlights the recent trends, challenges and future directions in the development of cellulose and NC-based commercial products.

Investigation of the effect of particle size of corn fiber, as potential raw material, on techno-functional and physicochemical properties

Corn fiber (CF) is an undervalued co-product of the corn starch and corn milling industry. Similar to CF, sieving is also important in the cereal industry and should receive sufficient scientific attention. Thus, the aim of this study was to evaluate the effect of particle size on the techno-functional and physicochemical properties of CF as an alternative to fiber-rich raw materials for the food industry. Granulometry showed low uniformity (0.34) and low span (0.93), which could affect processing and product quality. The coarser fractions had lower density, solubility, paste viscosity, color, protein, ash, lipid, phenolic compounds, and antioxidant activity than the finer fractions. However, these coarse fractions had high porosity (83%), water absorption index (2.77 g gel/g), and dietary fiber content (75.56 g/100 g). All the evaluated responses had 37 strong positive correlations and 34 strong negative correlations (p < 0.01). In addition, principal component analysis at 91.09% of the total variance revealed four distinct clusters that possessed similar characteristics in both techno-functional and physicochemical properties. Coarse fractions could generate greater extraction yields of hemicellulose and cellulose, whereas fine fractions could be excellent materials for the production of foods with excellent nutritional and functional properties.

Comparison of treatments for cellulose pulp from agro-industrial wastes from the Amazon region

Agroindustrial waste (AIW) is a potential source of cellulose, which can be obtained through different treatments. In this study, we evaluated four delignification treatments (10% sodium hydroxide, 50% ethanol, distilled water, and 25% Mohr's salt) to obtain cellulose pulp from four Amazonian AIWs (banana peel, cassava peel, sugarcane bagasse, and rice husk). Our results showed that sodium hydroxide treatment had the highest lignin removal and increased cellulose content, while Mohr's salt treatment had the lowest cellulose yield and lignin removal. Banana peel and rice husk had the highest cellulose yield, while cassava peel had the lowest. Distilled water treatment at medium temperature had similar lignin removal and cellulose yield to the sodium hydroxide and ethanol treatments. Our findings suggest that AIWs have great potential as a source of cellulose and that these economical, simple, and eco-friendly treatments can be used to obtain high-purity cellulose from AIWs.

Acetic acid bacteria in agro-wastes: from cheese whey and olive mill wastewater to cellulose

In this study, cheese whey and olive mill wastewater were investigated as potential feedstocks for producing bacterial cellulose by using acetic acid bacteria strains. Organic acids and phenolic compounds composition were assayed by high-pressure liquid chromatography. Fourier-transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction were used to investigate modifications in bacterial cellulose chemical and morphological structure. Cheese whey was the most efficient feedstock in terms of bacterial cellulose yield (0.300g of bacterial cellulose/gram of carbon source consumed). Bacterial cellulose produced in olive mill wastewater presented a more well-defined network compared to pellicles produced in cheese whey, resulting in a smaller fiber diameter in most cases. The analysis of bacterial cellulose chemical structure highlighted the presence of different chemical bonds likely to be caused by the adsorption of olive mill wastewater and cheese whey components. The crystallinity ranged from 45.72 to 80.82%. The acetic acid bacteria strains used in this study were characterized by 16S rRNA gene sequencing, allowing to assign them to Komagataeibacter xylinus and Komagataeibacter rhaeticus species. This study proves the suitability to perform sustainable bioprocesses for producing bacterial cellulose, combining the valorisation of agro-wastes with microbial conversions carried out by acetic acid bacteria. The high versatility in terms of yield, morphology, and fiber diameters obtained in cheese whey and olive mill wastewater contribute to set up fundamental criteria for developing customized bioprocesses depending on the final use of the bacterial cellulose. KEY POINTS: • Cheese whey and olive mill wastewater can be used for bacterial cellulose production. • Bacterial cellulose structure is dependent on the culture medium. • Komagataeibacter strains support the agro-waste conversion in bacterial cellulose.

Extraction of Pectin and Cellulose from Grapefruit Peels and Production of Carboxymethyl Cellulose

The peels of grapefruit are a rich source of Pectin and Cellulose. This study focuses on the extraction of Pectin and Cellulose from grapefruit peels, and the production of carboxymethyl Cellulose (CMC) from extracted products. Firstly, the extraction conditions of Pectin from grapefruit peels were optimized to obtain a high yield of Pectins such as extraction time and citric acid concentration. The weight, purity, and esterification degree of Pectin were also determined. The highest yield of Pectin is 32.12% in the extraction conditions with pH 1.25 for 60 minutes at 80 oC. The Pectin product is of 84.02% purity at 29,427 g/mol of weight with 86.40% esterification degree. For extraction of Cellulose from grapefruit peels, the highest yield of Cellulose is 45.08% in the conditions with a pH of nitric acid 0.75 for 70 minutes at 90 oC. After that, the extracted Cellulose was converted to Carboxymethyl Cellulose by Monochloroacetic acid etherification. The characterization of Pectin, Cellulose, and CMC is determined through Scanning Electron Microscopy (SEM) and Infrared spectrums. The experimental results also showed that Pectin and Cellulose were successfully extracted from grapefruit peels and Carboxymethyl Cellulose was successfully produced from the extracted Cellulose.

Acid preservation of cultivated brown algae Saccharina latissima and Alaria esculenta and characterization of extracted alginate and cellulose

Cultivated brown algae represent an important potential source of carbohydrate polymers for packaging and other biobased materials. However, their exploitation is currently limited by a short harvest season and a lack of cost-effective and sustainable methods to preserve biopolymer quality. In the present study, cultivated Saccharina latissima (SL) and Alaria esculenta (AE) were preserved with formic acid at 4, 13 and 20 °C for up to 16 weeks prior to extraction and characterization of alginate and cellulose. The data show up to 40 % increased yield of alginate from preserved biomass compared with fresh and non-preserved biomass, primarily due to removal of minerals and other soluble compounds during the acid wash. Acid preservation and storage caused a reduction in alginate weight average molecular weight (Mw) that was mainly dependent on storage temperature and to a lesser extent on storage time; storage at 4 °C maintained the Mw of alginates at 350–500 kDa. Preservation had no effect on the guluronate block structure of the extracted alginates, but guluronic acid content and block length increased in the non-preserved samples, presumably due to enzymatic degradation of the alginate's M-rich regions. Preservation of the seaweed resulted in an increased cellulose yield compared with fresh and non-preserved biomass, again due to the biomass being reduced during acid wash. The molecular weight and crystallinity of cellulose were not altered by the process. Altogether our findings demonstrate that acid preservation at low temperatures can effectively stabilize seaweed biomass while preserving alginate and cellulose quality for biomaterials and other applications.

DEVELOPMENT OF COMBINED ORGANOSOLV-TEMPO OXIDATION TREATMENT FOR OBTAINING CELLULOSE NANOFIBRES

The aim of this work was to study and optimize the production of nano-size cellulose fibrils (NFC) by combined performic acid treatment, totally chlorine-free (TCF) bleaching and TEMPO-oxidation prior to mechanical treatment. For this purpose, a face-centered design was developed in order to optimize the independent variables governing performic treatment. Under the optimal conditions, a kappa index of 13 was achieved, which decreased to 2.2 after bleaching treatment. These low-lignin pulps were TEMPO-oxidized under different oxidizing conditions, while monitoring cellulose yield, carboxylic acid content and the degree of polymerization. The optimized conditions produced oxidized pulp with 1.4 mmol COOH/g dried nanofibre. Finally, this oxidized cellulose was subjected to high-pressure mechanical processing in order to obtain cellulose nanofibres. From the results, it can be concluded that neither the number of homogenizer passes nor the pressure affected to diameter of fibrils.

Extraction and Characterization of Fiber and Cellulose from Ethiopian Linseed Straw: Determination of Retting Period and Optimization of Multi-Step Alkaline Peroxide Process

Flax is a commercial crop grown in many parts of the world both for its seeds and for its fibers. The seed-based flax variety (linseed) is considered less for its fiber after the seed is extracted. In this study, linseed straw was utilized and processed to extract fiber and cellulose through optimization of retting time and a multi-step alkaline peroxide extraction process using the Taguchi design of experiment (DOE). Effects of retting duration on fiber properties as well as effects of solvent concentration, reaction temperature, and time on removal of non-cellulosic fiber components were studied using the gravimetric technique, Fourier transform infrared (FTIR) spectroscopy and thermal studies. Based on these findings, retting for 216 h at room temperature should offer adequate retting efficiency and fiber characteristics; 70% cellulose yield was extracted successfully from linseed straw fiber using 75% ethanol-toluene at 98 °C for 4 h, 6% NaOH at 75 °C for 30 min, and 6% H2O2 at 90 °C for 120 min.

Zirconium Phosphate Assisted Phosphoric Acid Co-Catalyzed Hydrolysis of Lignocellulose for Enhanced Extraction of Nanocellulose.

The high mechanical strength, large specific surface area, favorable biocompatibility, and degradability of nanocellulose (CNC) enable it to be a potential alternative to petroleum-based materials. However, the traditional preparation of CNCs requires a large amount of strong acid, which poses a serious challenge to equipment maintenance, waste liquid recycling, and economics. In this study, a solid and easily recoverable zirconium phosphate (ZrP) was used to assist in the phosphoric acid co-catalyzed hydrolysis of lignocellulose for extracting CNCs. Due to the presence of acidic phosphate groups, ZrP has a strong active center with a high catalytic activity. With the assistance of ZrP, the amount of phosphoric acid used in the reaction is significantly reduced, improving the equipment's durability and economic efficiency. The effects of the process conditions investigated were the phosphate acid concentration, reaction temperature, and reaction time on the yield of CNCs. The Box-Behnken design (BBD) method from the response surface methodology (RSM) was applied to investigate and optimize the preparation conditions. The optimized pre-treatment conditions were 49.27% phosphoric acid concentration, 65.38 °C reaction temperature, and 5 h reaction time with a maximal cellulose yield (48.33%). The obtained CNCs show a granular shape with a length of 40~50 nm and a diameter of 20~30 nm, while its high zeta potential (-24.5 mV) make CNCs present a stable dispersion in aqueous media. Moreover, CNCs have a high crystallinity of 78.70% within the crystal type of cellulose Ⅰ. As such, this study may pioneer the horizon for developing a green method for the efficient preparation of CNC, and it is of great significance for CNCs practical production process.

Structure analysis of biomass after alkali-freeze pretreatment for one-pot production of C5 and C6 sugars with magnetic acid catalyst

In this work, freeze pretreatment of biomass with 1–13 wt% KOH was applied for one-pot production of C5 and C6 sugars with C-SO3H@Fe3O4/C catalyst. Crystalline structures indicated cellulose I to cellulose II appeared at 4 wt% KOH, and cellulose II reached the maximum (40.1 % to 61.9 % for wheat straw vs 34.8 % to 60.8 % for corn straw) at 10 wt% KOH. High yields of cellulose (60.4 % for wheat straw vs 68.3 % for corn straw) and hemicellulose sugar (84.2 % for wheat straw vs 83.8 % for corn straw) were achieved in 10 wt% KOH-freeze pretreated biomass with C-SO3H@Fe3O4/C at 180 °C. Moreover, the catalyst was magnetically separated with high recovery rate (90.1 %). Yields of cellulose (52.2 %, 50.2 %) and hemicellulose sugar (70.3 %, 60.1 %) for wheat and corn straw were obtained after 5 cycles, individually. This study demonstrates freeze-KOH pretreatment can effectively promoteone-pot production of C5 and C6 sugars by crystallinity amelioration.

Extraction of high-quality grade cellulose and cellulose nanocrystals from different lignocellulosic agri-food wastes

IntroductionPrompted by the increasing need for an intensified valorization of agri-food waste, in this work a three-step chemical procedure was used to extract high-purity cellulose from garlic stalk, corncob, and giant cane cut-up by a sequential removal of hemicellulose, lignin, ash, and organic compounds. Cellulose nanocrystals of potential interest for nanocomposite applications were then obtained through acid hydrolysis.MethodsThe purity of the cellulose was determined employing Nuclear Magnetic Resonance and infrared spectroscopy, whereas dynamic light scattering, optical, atomic force microscopy, and transmission electron microscopy were used for morphological characterization. The high purity and crystallinity of cellulose was confirmed by comparison with the ultra-pure bacterial cellulose originating from K. sucrofermentans, irrespective of the waste used.Results and discussionAt the end of the extraction procedure, cellulose yields of 35.73, 37.15, and 39.10%, for garlic stalk, corncob, and giant cane cut-up, respectively, were achieved. Dynamic light scattering and atomic force microscopy analyses showed that the length of the whisker-like nanocrystals depended on the raw material (from ~100 nm up to &amp;gt; 2μm), while the final yield was ~40–50% for all three wastes. The versatility and effectiveness of the method here proposed can be profitably used for a wide range of agro-waste feedstocks.

Extraction of cellulose from paulownia plants and its simple ester carboxymethyl cellulose (na-kms) technology

In this experiment, Paulownia fiber plant is ground to 0.5-1 cm. In order to determine the optimum alkali solution concentration to extract cellulose from the raw material, the optimum degree of polymerization was determined by boiling in 25, 35, 50, 55 g/l solution. It can be seen from the table that certain properties of cellulose produced under the influence of different concentrations of alkali have different indicators. At alkaline concentration of 50 g/l, the cellulose yield was 49.6%, α-cellulose 89.5%, and the degree of polymerization was known in 1100 experiments. Ash content was a positive indicator of 1.78%. The scientific essence is that the cellulose is first soaked in isopropyl alcohol and mercerized in caustic alkali (NaOH) solution. Then, the alkylation process is carried out by adding a certain amount of monochloroacetic acid to the alkaline cellulose. Then, the alkylation process is carried out by adding a certain amount of monochloroacetic acid to the alkaline cellulose. The resulting carboxymethylcellulose is sent for purification. Na-CMC with 38-40% moisture content is washed in 53% ethyl alcohol and dried.

Preliminary Study on the Effect of Bleaching Treatment on Cellulose Extracts from Oil Palm Empty Fruit Bunch

Oil palm empty fruit bunch fibre (OPEFB) is a waste from palm oil mill. It is rich in useful compound residues such as cellulose and carboxymethylcellulose. The increasing interest in OPEFB as a source of cellulose is due to its low cost, renewable and abundantly available, particularly in the Southeast Asia region. Cellulose extraction is affected by pre-treatment, especially during the bleaching process. Thus, this study aims to analyse the effect of bleaching period and treatment using NaClO2 on cellulose recovery from OPEFB. Batch process of bleaching was carried out in the ratio of 1:50 of fibres to sodium chlorite (NaClO2) solution of 0.7%. This was followed by analysis of cellulose morphological using FTIR and SEM analysis. The study found that bleaching duration affects cellulose recovery, with the highest yield of 54% found to be at 3 hours of bleaching duration. The bleaching duration was increased up to 6 hours, but found to yield less cellulose, which indicated that certain duration is suitable to provide a condition for higher cellulose yield.

Synthesis and characterization of superabsorbent natural polymers from agro-waste fibres

This work focuses on synthesizing superabsorbent material from polysaccharides, which are derived from environment-friendly raw materials like ligno-cellulosic agro-waste. Three ligno-cellulosic agro-waste fibres, namely banana, sisal and bagasse, have been taken for the present study, to synthesize natural superabsorbent polymer which are eco-friendly and bio-degradable. Cellulose has been extracted from sisal, bagasse and banana, of which cellulose yield has been high for banana fibres. Carboxy methyl cellulose (CMC) synthesized from the extracted cellulose is cross-linked with aluminium sulphate octadecahydrate to subsequently synthesize superabsorbent polymer from these agro-waste fibres. The sysnthecised CMC from all the three agro-waste fibres shows great reduction in immersion time; CMC from sisal shows the least immersion time of 2.67 s. Banana fibres have recorded the highest degree of substitution. The superabsorbent polymer synthesized from banana fibres has shown an increase in absorbency and swelling rate but reduction in immersion time. This owes to the higher yield of cellulose and the higher degree of substitution attained in the case of banana fibres. This has been proved by chemical composition, SEM and FTIR analyses. This study helps in developing eco-friendly superabsorbent sanitary napkins.

Improving carbon yield of bacterial cellulose derived carbon by phosphorus/nitrogen doping

In this study, porous bacterial cellulose (BC) mat was prepared by freeze-thawing of BC hydrogel obtained from the kombucha fermentation process. Then, the porous BC was dyed with a nitrogen containing carbonyl dye (C.I. Vat Olive B) followed by phosphorus doping and employed as a precursor for preparation of carbon nanofilament. The P/N doped BC mat precursor was stabilized at 330 ºC for 2 h and carbonized at 800 ºC for 2 h. SEM images confirmed that BC based carbon exhibited the entangled filament structure. To follow the conversion of BC mat to carbon nanofilament, FTIR analysis and Raman spectroscopy were carried out. FTIR spectra of stabilized mats showed that the cellulose carbon-carbon double band centered at 1600 cm -1 appeared strongly. In contrast, the intensity of this band markedly decreased at carbonization stage, resulting from the conversion of cellulose carbon-carbon double bond into carbon aromatic ring which exhibited weak intensity. The graphitic structure was confirmed by the presence of sp 3 disorder hybridization and sp 2 hybridization (D and G bands, respectively) shown in Raman spectra). In addition, XRD diffractograms further confirmed the existence of amorphous carbon peak found at 26º, indicating that the P/N dopants played a role in inducing the graphitic structure as well as improving carbon yield. Finally, the electrochemical performance as a carbon electrode were revealed.

Removal of heavy metal vanadium from aqueous solution by nanocellulose produced from Komagataeibacter europaeus employing pineapple waste as carbon source

Environmental concerns have taken a center stage in our lives driving the society towards biorefinery. Bioprocess development to produce valuable products utilizing waste has its own significance in circular bioeconomy and environmental sustainability. In the present study, production of bacterial cellulose using pineapple waste as carbon source by Komagataeibacter europaeus was undertaken and it was applied for removal of vanadium, a heavy metal which is generated as waste by semiconductors industry in Taiwan. Highest yield of bacterial cellulose (BC) e.i. 5.04 g/L was obtained with pineapple core hydrolysate (HS-PC) replacing glucose in HS medium. The vanadium adsorption capacity by BC produced by HS medium was 5.24 mg/g BC at pH 4 and 2.85 mg/g BC was observed on PCH medium. BC was characterised via SEM, FTIR and XRD.