Covernov DEC15 FINAL

FIBRES PEER REVIEWED Microscopic, IR-Spectroscopic and Thermal Analysis on Biodegradability of Jute Himansu Shekhar Mohapatra & Kamal Kanti Goswami Indian Institute of Carpet Technology, Bhadohi Abstract Natural cellulosic fibres like cotton, linen, jute etc are mainly composed of biopolymers available in the biospheres. Products produced from biopolymers including cellulose are very susceptible for microbial growth which can leads to many aesthetic, functional problems and even infection. The present study focuses on preparation and characterization of biodegradation of jute well known for its lignocellulosic composition. The study includes characterization tests such as morphological analysis through optical and scanning electron microscopy, functional group analysis through infrared spectroscopy and thermal analysis through thermo gravimetric analysis. Keywords Biodegradation, Jute, Microorganism, SEM, FTIR, TGA. 1. Introduction exposed. Some of the important factors that directly Degradation is a process of breaking down a material influence the rate of biodegradation are presence of into its constituent elements by a physical, chemical or microorganism, availability of oxygen, availability of a biochemical process which should be irreversible. water, temperature and pH etc. [1]. Microorganisms When this process of degradation is aided by the at- attack on any kind of fibre or material surface in vari- tack of living matter especially microorganisms, re- ous steps like 1) Microorganisms stick onto the sur- sulting into mineralization or biomass, it becomes face of a material either by adhesion or aggregation, Biodegradation [1]. There are two types of biodegra- 2) proliferation of attached microbial cells, 3) produc- dation, aerobic and anaerobic. When material is biode- tion of enzymes, 4) biodegradation of materials, 5) graded in the presence of oxygen it is called aerobic reduction of degree of polymerization of material poly- biodegradation and if without oxygen then anaerobic mer and production of degradable products. [2]. biodegradation. For a material to be completely biodegraded it must be converted into carbon dioxide, water Cellulose is composed of insoluble, linear chains of and minerals and the intermediate products should glucose units linked by b-1, 4-glucosidic bonds . It is contain biomass [1]. Both the aerobic and anaerobic composed of highly crystalline regions and (non-crys- types of biodegradation are represented in below talline) regions forming a structure generally resistant mechanisms to enzymatic hydrolysis, especially the crystalline regions [3]. The cellulose fibers are usually embedded . Cpolymer + O2 CO2 + H2O + Cresidue + Cbiomass + Salts in an amorphous matrix of hemicelluloses and lignin . Cpolymer CO2 + CH4 + H2O + Cresidue + Cbiomass + Salts [4]. Where, Cpolymer represents either a polymer or a fragment that is considered to be composed only of In native cellulose the cellulose chains are oriented in carbon, hydrogen and oxygen. When Cpolymer is a parallel super molecular structure in which inter- completely converted into gaseous products and salts, molecular hydrogen bonding between contiguous cel- then the biodegradation is completed [1]. lulose molecules, results in a sheet-like structure in the cellulose fibers [5]. The biodegradation of materials depend upon the polymer chemistry and the environment in which they are The major component of lignocellulose materials is cellulose, along with lignin and hemicellulose. Cellu- Association TEXTILE *All the correspondence should be addressed to, lose and hemicellulose are macromolecules from dif- Himansu Shekhar Mohapatra ferent sugars; whereas lignin is an aromatic polymer Indian Institute of Carpet Technology, synthesized from phenylpropanoid precursors. The Bhadohi, UP-221401, India Journal of the November - December 2015 217 FIBRES composition and percentages of these polymers vary that of Clostridium thermocellum, a strict anaerobic from one plant species to another. Moreover, the com- gram-positive, sporulated bacterium. position within a single plant varies with age, stage of growth, and other conditions [6]. Long cells envel- Hemicelluloses are biodegraded to monomeric sugars oped by a characteristic cellular wall form wood. This and acetic acid. Hemicellulases are frequently classi- wall is a complex structure that acts at the same time fied according to their action on distinct substrates. as plant skin and backbone. Xylan is the main carbohydrate found in hemicellulose. Its complete degradation requires the cooperative The biological degradation of cellulose, hemicellulose, action of a variety of hydrolytic enzymes. An impor- and lignin has attracted the interest of microbiologists tant distinction should be made between endo-1,4-b- and biotechnologists for many years. The diversity of xylanase and xylan 1,4-b-xylosidase. The former gen- cellulosic and lignocellulosic substrates has contrib- erates oligosaccharides from the cleavage of xylan; uted to the difficulties found in enzymatic studies. Fungi the latter works on xylan oligosaccharides, producing are the best-known microorganisms capable of degrad- xylose [6]. ing these three polymers. Because the substrates are insoluble, both bacterial and fungal degradation have The structural complexity of lignin, its high molecular to occur exocellularly, either in association with the weight and its insolubility make its degradation very outer cell envelope layer or extracellular. Microorgan- difficult. Extracellular, oxidative, and unspecific en- isms have two types of extracellular enzymatic sys- zymes that can liberate highly unstable products which tems: the hydrolytic system, which produces hydroly- further undergo many different oxidative reactions ses and is responsible for cellulose and hemicellulose catalyze the initial steps of lignin depolymerization. degradation; and a unique oxidative and extracellular This non-specific oxidation of lignin has been referred ligninolytic system, which depolymerizes lignin. to as ''enzymatic combustion'' [9]. White-rot fungi are the microorganisms that most efficiently degrade lig- Most of the cellulolytic microorganisms belong to nin. Degradation of lignin and lignin-degrading en- eubacteria and fungi, even though some anaerobic zymes has also been reported for actinobacteria from protozoa and slime molds able to degrade cellulose the Streptomyces genus [4]. Even though lignin bio- have also been described. Cellulolytic microorganisms degradation is accepted as an aerobic process, some can establish synergistic relationships with non-cellu- authors have reported that anaerobic microorganisms lolytic species in cellulosic wastes. The interactions in the rumen may alter, if not partially degrade, por- between both populations lead to complete degrada- tions of lignified plant cells [10]. tion of cellulose, releasing carbon dioxide and water under aerobic conditions,and carbon dioxide, methane In this present study, an attempt has been made to and water under anaerobic conditions [7,8]. understand the process of biodegradation of jute fabric when they are subjected to soil burial test. Microorganisms capable of degrading cellulose pro- duce a battery of enzymes with different specificities, 2. Materials working together. Cellulases hydrolyze the b-1,4-gly- The materials were used for the present study of bio- cosidic linkages of cellulose. Traditionally, they are degradation is jute fabric which are shown in Figure divided into two classes referred to as endoglucanases 2.1. The dimensions of the samples were 5× 5 cm2 and and cellobiohydrolases. Endoglucanases (endo-1,4-b- the sample weight was 25gm of each sample. glucanases, EGs) can hydrolyze internal bonds (pref- erably in cellulose amorphous regions) releasing new terminal ends. Cellobiohydrolases (exo-1,4-b- glucanases, CBHs) act on the existing or endoglucanase- generated chain ends. TEXTILE Association About 5-10% of cellulose is degraded in nature under anaerobic conditions. The cellulose system of anaerobic microorganisms is clearly different from that of aerobic fungi and bacteria. The best characterized is Journal of the Figure 2.1 (Optical image of Jute fabric) 218 November - December 2015 FIBRES 3. Experimental Procedure is recorded as function of temperature. The weighing In this experiment samples of jute of fabric were cut of the sample is done by a thermo-balance which is into pieces of 5x5 cm2 and four samples were ana- present inside the furnace. lyzed when they were buried in soil according to the ISO 11721-1:2001 and ISO 11721:2003 standards. The 4. Results and Discussions samples are buried in such a way that all four pieces 4.1. Microscopic analysis of jute of jute fabric are buried in a separate beaker of 1000 Then jute samples before experimentation and taken ml. After every week soil from all beakers is taken out out from soil after seven, fourteen, twenty one and and moisturized with distilled water, after that soil twenty eight days have been analyzed visually and with samples is again put back in the beakers and one with the help of optical and scanning electron micro- piece of jute fabric is kept out to study the effect of scope. The findings are pictorially represented in Fig- microorganisms. These samples are first rinsed in etha- ure 4.1. nol/water (70%/30% volume fraction) solution for approximately 10 min before drying at room temperature and after that further experiment were conducted. 3.1. Evaluation by Nikon Eclipse (E200) Optical Mi-

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