NMR methods have been designed and employed in studying ofcomplex liquids and solids formed by surfactants. PGSE NMRexperiments are easily biased by convection; this artifact canbe avoided by changing the sample holder and by usingconvection-compensated pulse sequences. The temperaturedistribution within samples was controlled using thetemperature dependent order parameter for CBr2H2dissolved in a thermotropic nematic solvent.Electronic ringing that often spoils accurate NMR experimentsfor broad lines was removed by the using composite pulses andquadrupole echo sequences with appropriate phase cycles. Field-dependent81Br and35Cl NMR relaxation studies in micellar solutions ofC16TAX surfactants showed that the structure ordynamics of the hydration shell is more influenced by thesurfactant cation for bromide than for chloride, in agreementwith their position in the Hoffmeister series. The presence ofa small but significant frequency-dependent relaxation showedthat the lateral self diffusion of the anions may be reduced ascompared to its bulk value in diluted solutions but only with afactor of 1.0 - 2.5. The ions are clearly not "bound" to thesurface. A field-dependent2H NMR relaxation study on the CTABr-α-d2and benzene-d6showed an initial one-dimensional micellargrowth followed by the appearance of microemulsion droplets onaddition of benzene. The local mobility of the benzene wasreduced when solubilized in small amounts, consistent with aninitial average location of benzene at the micellar interface.The surfactant diffusion coefficients fromconvection-compensated PGSE NMR experiments in the C12E8-D2O system showed monotonous growth of the micellesupon increasing temperature. Emulsion droplets in the C12E5-decane-D2O system where shown to coarsen according to theOstwald ripening theory after being brought out of equilibriumby a temperature drop. X-ray scattering and2H NMR line-shape and relaxation experimentssuggested that complex solids formed by a partly-sulfatedpolysaccharide and CnTAB exhibit regular ordering at both microscopicand mesoscopic length scales. <b>Keywords</b>: CTAB, CTAC, C12E8, C12E5, decane, benzene, CBr2H2, polysaccharide, micelle, microemulsion, emulsion,Ostwald ripening, NMR,81Br,35Cl,2H, field- dependent spin relaxation, PGSE, selfdiffusion, convection, ringing, thermometer, generalized Blochequations, EXORCYCLE, quadrupole echo, SAXS, WAXS, cryo-TEM.

Diatoms are estimated to contribute 25 percent of the primary production on Earth and therefore they play a significant role in the global carbon cycle. Diatom blooms often terminate with the formation of aggregates that sink rapidly from surface waters, affecting the flux of organic carbon from the surface to deep waters and the sea floor. The role of carbon-rich transparent exopolymeric particles (TEP) in aggregate formation as ocean temperature increases has yet to investigated in continuous cultures. I hypothesize that temperature increase can influence the production of TEP, a fraction of total suspended exopolymers. To test the hypothesis, a laser in situ scattering and transmissometry instrument (LISST-100X, Sequoia Instruments) successfully counted and sized six individual diatom species in batch culture: Chaetoceros muelleri, Coscinodiscus wailesii, Thalassiosira weissflogii, Phaeodactylum tricornutum, Skeletonema costatum, and Skeletonema marinoi and successfully demonstrated its efficacy in detecting diatom aggregates using S. costatum. Four replicate continuous cultures were sampled for particle size distribution (PSD), nutrients, chlorophyll a, total carbohydrates, prokaryote concentration, and TEP at temperatures of 22.5, 27 and then 20 degrees C. While TEP particles were scarce, acid polysaccharide (APS)-coated C. muelleri cells were observed, forming dense webs on the filters. Both carbohydrate per cell and APS area per cell were found to significantly correlate with temperature (p<0.05) while significant difference between APS concentration at each temperature was only found between 27 and 22.5 or 20 degrees C (p<0.05). Net changes in PSDs with increasing temperature showed that distributions of relative volume concentration decreased in the smallest size bins and increased in the largest size bins. Our results show that increasing the temperatures of nitrogen-limited C. muelleri cultures did not cause increased TEP formation but instead resulted in increased cell-surface coating. Increasing concentration of cell coatings and TEP particles will cause diatoms to aggregate more readily, enhancing their sinking rate away from the ocean surface. Increased ocean temperature has great implications for diatom blooms and other microorganisms, causing greater export of carbon out of the surface waters and potentially altering the microbial loop.

<p>NMR methods have been designed and employed in studying ofcomplex liquids and solids formed by surfactants. PGSE NMRexperiments are easily biased by convection; this artifact canbe avoided by changing the sample holder and by usingconvection-compensated pulse sequences. The temperaturedistribution within samples was controlled using thetemperature dependent order parameter for CBr₂H₂dissolved in a thermotropic nematic solvent.Electronic ringing that often spoils accurate NMR experimentsfor broad lines was removed by the using composite pulses andquadrupole echo sequences with appropriate phase cycles.</p><p>Field-dependent⁸¹Br and³⁵Cl NMR relaxation studies in micellar solutions ofC₁₆TAX surfactants showed that the structure ordynamics of the hydration shell is more influenced by thesurfactant cation for bromide than for chloride, in agreementwith their position in the Hoffmeister series. The presence ofa small but significant frequency-dependent relaxation showedthat the lateral self diffusion of the anions may be reduced ascompared to its bulk value in diluted solutions but only with afactor of 1.0 - 2.5. The ions are clearly not "bound" to thesurface. A field-dependent²H NMR relaxation study on the CTABr-α-<i>d</i><i>2</i>and benzene-<i>d</i><i>6</i>showed an initial one-dimensional micellargrowth followed by the appearance of microemulsion droplets onaddition of benzene. The local mobility of the benzene wasreduced when solubilized in small amounts, consistent with aninitial average location of benzene at the micellar interface.The surfactant diffusion coefficients fromconvection-compensated PGSE NMR experiments in the C₁₂E₈-D₂O system showed monotonous growth of the micellesupon increasing temperature. Emulsion droplets in the C₁₂E₅-decane-D₂O system where shown to coarsen according to theOstwald ripening theory after being brought out of equilibriumby a temperature drop. X-ray scattering and²H NMR line-shape and relaxation experimentssuggested that complex solids formed by a partly-sulfatedpolysaccharide and C_nTAB exhibit regular ordering at both microscopicand mesoscopic length scales.</p><p><b>Keywords</b>: CTAB, CTAC, C₁₂E₈, C₁₂E₅, decane, benzene, CBr₂H₂, polysaccharide, micelle, microemulsion, emulsion,Ostwald ripening, NMR,⁸¹Br,³⁵Cl,²H, field- dependent spin relaxation, PGSE, selfdiffusion, convection, ringing, thermometer, generalized Blochequations, EXORCYCLE, quadrupole echo, SAXS, WAXS, cryo-TEM.</p>

Chitosan films are an excellent media for binding metal ions due to the electrostatic nature of the chitosan molecules. Addition of cross-linking or plasticizing agents alters texture of the films, but their effect on metal-binding capacity has not been fully characterized. The objective of this research was to determine effects of plasticizers and cross-linkers on physical and metal-binding properties of chitosan films and coatings prepared by casting and by spincoating. Chitosan films were prepared using 1% w/w chitosan in 1% acetic acid with or without (control) additives. Plasticizing agents were tetraethylene glycol (TEG) and glycerol while citric acid, ethylenediamine tetraacetic acid (EDTA), and tetraethylene glycol diacrylate (TEGDA) were used as cross-linkers. The additives were applied in concentrations of 0.10%, 0.25%, and 0.50% w/w of film-forming solution. The films were prepared by casting and by spincoating. Films were cast at ambient conditions for tests within one week (fresh films) and eight weeks (aged) after casting. The cast films were evaluated for thickness, residual moisture (by the Karl Fischer method), Cr(VI) binding capacity, puncture strength, and puncture deformation while the chitosan coatings were tested for thickness, Cr(VI) binding capacity, solubility in aqueous solution, and surface morphology (using atomic force microscopy). Cast films with cross-linkers showed an increase in resistance to puncture while plasticized films become more elastomeric. Control films bound 97.2% Cr(VI) ions from solution (0.56 mg Cr(VI)/g film), and addition of plasticizers did not affect chromium binding, tying up to 96.7% Cr(VI) ions from solution (0.56 mg Cr(VI)/g film). Films containing cross-linkers yielded binding capabilities ranging from 42.3% to 94.3% bound Cr(VI) ions (0.26-0.52 mg Cr(VI)/g film). Ultrathin coatings also possess the ability to bind Cr(VI) from solution, though only a maximum of 7.4% of Cr(VI) ions could be bound from solution, the thin films had the ability to bind up to 224 mg Cr(VI)/g ultrathin film. These coatings use less chitosan, but they display greater binding per mass. Overall, plasticizers do not alter, while cross-linkers may reduce, the binding capacity of chitosan films, but physical properties of the films can be controlled by inclusion of additives.

Soy whey protein isolate (SWPI) – Fenugreek gum conjugates were developed and their molecular characteristics and emulsifying properties were investigated. SWPI was extracted from soy whey of tofu processing. SWPI exhibited excellent emulsifying properties comparable to soy protein isolate. However, to improve the emulsifying properties of SWPI for some applications, it was conjugated to fenugreek gum. The extent of conjugation was verified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), Fourier transform infrared (FTIR) and High performance size exclusion chromatography (HPSEC). The SDS-PAGE of the conjugates showed polydispersed bands at the top of the separating gel in the conjugates suggesting the formation of high molecular weight products. Refractive index spectrum of HPSEC profiles showed a reduction of protein peak of unconjugated mixture and shifted a peak to higher molecular weight of the conjugates. Ultraviolet spectrum of HPSEC showed an increase of protein peak intensity at polysaccharide region. FTIR spectrum showed an amide band I and II were still observed in the conjugates after the unreacted proteins were removed. 1D NMR spectra showed that fenugreek gum was covalently bound to proteins through interaction between the reducing end of mannose residue and lysine. The protein solubility of SWPI – Fenugreek gum conjugates improved as compared to SWPI and SWPI – Fenugreek gum mixture when assessed in the pH range 3 to 8 at 22oC, especially at isoelectric point of protein (pl). A 1:3 and 1:5 ratio of SWPI – Fenugreek gum gave rise to better emulsion stabilization compared to 1:1 ratio. Particle size analysis revealed that conjugation of SWPI – Fenugreek gum at 60oC for 3 days was enough to produce relatively small droplet sizes in oil-in-water emulsions. SWPI – Unhydrolyzed fenugreek gum conjugates exhibited better emulsifying properties compared to SWPI – Partially hydrolyzed fenugreek gum conjugates. The conjugates improved emulsifying properties of SWPI, particularly around the pl of protein. The emulsifying properties were greatly increased by heating the conjugates before emulsification. The conjugates also improved emulsion stability at high salt concentration compared to SWPI. In summary, incorporation of SWPI into fenugreek gum improved emulsifying properties of SWPI near the pl of protein and at high salt concentration. / No / No

The total and soluble nonstarch polysaccharide (NSP) components of raw, processed (canned and frozen) and home-cooked (boiled) Royal Chantenay carrots have been analyzed. NSP fractions were characterized by separation and summation of the monosaccharides resulting from acid hydrolysis of the parent polysaccharides. Total NSP was primarily composed of glucose, ~37%, and uronic acid, ~35%, containing polysaccharides. Soluble NSP was composed of >50% uronic acids. Processing and simulated home-cooking of raw carrots resulted in an increase in the amount of NSP/unit dry weight. Relative to raw carrots, cooking of canned product resulted in the largest (~2-fold) increase in total and soluble NSP/unit dry weight. Relative differences in NSP were not as great when compared on a wet weight basis. / Graduation date: 1995

Hyaluronic acid (HA) is a biopolymer with valuable applications in the pharmaceutical and cosmetic industries. The molecular weight of HA is important for its rheological, biological and commercial properties. Currently, high molecular weight HA is extracted from animal sources. Recent pandemic outbreaks of viruses H5N1 and H1N1 (avian and swine influenza) have raised concerns regarding the safety of animal-derived pharmaceuticals; making fermentation the preferred source of HA. Throughout this study, the mechanism of molecular weight control of HA polymerisation in S. zooepidemicus was investigated. While several aspects are still unknown, it was found that levels of activated monomers, (UDP-sugars) have a fundamental role in molecular weight control. High levels of activated sugars strongly correlated with high molecular weight. Throughout rational strain engineering, several strains harbouring a collection of genes were engineered using S. zooepidemicus as a host microorganism. Five genes of the so-called has operon were cloned into a nisin inducible plasmid and transformed into S. zooepidemicus. Several significant changes were observed in HA molecular weight. In order to understand those changes as a complex system, rather than isolated parts of the cell, a systems approach was undertaken. The main goal of this approach was to examine the structure and dynamics of cellular functions using global measurements on changes in proteins or metabolite concentrations, in response to genetic perturbations. As part of the systems biotechnology approach, methods for proteins and metabolites harvesting were optimised. Harvesting metabolites and proteins in microorganisms is a non-trivial process (Chapter 4 and 5). Encapsulated bacteria presents additional challenges since capsular polysaccharides interfere with extraction and downstream analysis. In terms of metabolite harvesting, several studies have reported rapid turnovers in low abundant intracellular sugar metabolites. Four different protocols for cellular harvesting were tested. The best method found was centrifugation, which allowed for efficient medium removal and enabled quantification of the broadest range of sugar metabolites. Unlike observations for other microbes, changes in metabolite pools due to a delay of extraction by centrifugation were not observed. Our hypothesis was that the capsule itself isolates the cells from their surroundings and still supports them with nutrients during cellular harvesting (Chapter 3). Protein harvesting also proved to be technically challenging (Chapter 5), especially when fluorescent dyes were employed for protein visualisation(Chapter 6). Despite this, using hyaluronidase to remove the HA capsule the first reference map for S. zooepidemicus was completed. Besides giving insight into the most abundantly expressed proteins, as well as facilitating the design of better diagnostics and treatments for streptococcal infections, our reference map can be used to engineer superior production strains (Chapter 5). In Chapter 6, proteins involved in MW control were separated using 2D differential in gel electrophoresis (DIGE) and identified by mass spectrometry. Moreover, the wild-type was compared with both the empty vector control strain and a high molecular-weight producing strain harbouring phosphoglucoisomerase (pgi). An enzyme involved in controlling the levels of the intracellular pool of one of the activated sugars, UDP-N-acetylglucosamide-1-carboxivinyltransferase, was down-regulated in the control line. Overexpression of UDP-N-Acetylglucosamide 1-carboxivinyltransferase, decreased both the concentration of activated precursors and HA molecular weight. Gene knockout of one of the copies of that particular gene could potentially guide us to further improvement of the strain. By overexpressing all the genes involved in the HA pathway (Appendix A) we have pushed gene expression as far as possible and the next option was to look at process optimisation. Several studies have found that culture conditions affect HA molecular weight: higher molecular weight is produced under aerobic conditions and when using maltose as the carbon source. To overcome the lower sugar uptake and growth rate observed under maltose, a two stage batch fermentation process was conducted. By feeding glucose when cell growth was stopped through amino acid auxotrophy, we achieved high molecular weight HA production in stationary phase. Using engineered strains, HA >5 MDa was obtained (Chapter 7). This thesis represents a good example of systems biotechnology for strain improvement and is a step forward in understanding the mechanism of molecular weight control of HA production by bacterial fermentation.

Univ., Diss.--Regensburg, 1992.

München, Techn. Univ., Diss., 2004.

Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Lignocellulosic material is composed of three major macromolecule components i.e., cellulose, hemicelluloses and lignin. These components are chemically associated and directly linked to each other through covalent bonding which is scientifically denoted as lignin-carbohydrate complexes (LCCs) and their interaction is fundamentally important as to understand wood formation and reactivity during chemical and biological processing e.g. pulping and enzymatic hydrolysis. The association of lignin with polysaccharides (covalent linkages) has been surrounded by contradictions and controversy in several wood chemistry studies. These linkages exist in lignocellulosic materials from wood to herbaceous plants. In woody plants, they consist of ester and ether linkages through sugar hydroxyl to α-carbonyl of phenyl-propane unit on lignin. However, in herbaceous plants ferulic and p-coumaric acids are esterified to hemicelluloses and lignin respectively. In recent studies, the existence of the bonds has been shown by applying indirect analysis strategies which resulted to low yields and contaminations. The general aim of the current study was to isolate and fractionate LCCs from raw lignocellulosic materials (E. grandis and sugarcane bagasse) and corresponding processed materials (chemical pulps and water-insoluble residues (WIS)) in order to determine the chemical structure of the residual lignin associated with polysaccharides and how they affected industrial processing. The objective of the study is to compile a document that when the development of pulping and bio-ethanol bio-refinery will greatly depends on the detailed wood chemistry on how the components interact with each before and after hemicelluloses pre-extraction prior to pulping and steam explosion pre-treatment prior to enzymatic hydrolysis. The current study was focusing on understanding the effect LCCs isolated from two different industrial processing methods, i.e. pulping and enzymatic hydrolysis (EH). There were two lignocelluloses feedstocks used for pulping, i.e. Eucalyptus grandis and sugarcane bagasse whereas sugarcane bagasse was the only feedstock used for enzymatic hydrolysis. Hemicelluloses pre-extracted (mild alkali or dilute acid and autohydrolysis for sugarcane bagasse) pulps of Kraft or soda AQ from E. grandis and sugarcane bagasse were used to understand the effect of xylan pre-extraction prior to pulping on lignin-carbohydrate complexes has not been reported to the best knowledge of the primary author. Also prior to EH the material was subjected to two different treatment methods, i.e. steam explosion and ionic liquid fractionation in varying conditions. The study illustrated the types of extracted and fractionated LCCs from hemicelluloses pre-extracted pulps and WIS in comparison to the non-extracted pulps and reports from the literature. Lignin-carbohydrate complexes (LCCs) were isolated and fractionated by an inorganic method which yielded reasonable quantification quantities and no contamination and low yields for the hardwood compared to reports of using an enzymatic method. To the best knowledge of the authors, no work has been done on WIS material. The lignocelluloses were subjected to ball milling which was followed by a sequence of inorganic solvents swelling and dissolution into 2 fractions i.e. glucan-lignin and xylan-lignin-glucan. Characterisation of the isolated LCCs was made using a variety of analytical tools such as FTIR-PCA, HPLC, GPC and GC-MS. LCCs were evident when FTIR and HPLC studies were conducted. Residual lignin isolated from the lignocelluloses was assumed to be chemically bonded to carbohydrates and mostly to xylan. Approximately 60% and 30% of the lignin was linked to xylan while for the second and first fractions respectively. It is reported that lignin associated with xylan is more resistant and reduce the delignification process than when linked to glucan that is easily hydrolysable. With the FTIR and GPC analyses of LCC fractions, it was evident that the ester bonds of LCCs were destroyed through pre-extraction and pre-treatment, where this resulted to more cellulose being more accessible to alkaline pulping and enzymatic hydrolysis respectively. The linkages were either partially broken down or completely destroyed leading to significant changes of chemical structures. The polydispersity of the LCCs assisted in determining the structure of lignin, either existing as monolignols on the surfaces of fibres or a as complex two or three-dimensional structure that is linked to carbohydrates as the Mw increased or decreased. In general, these findings may have an important implication for the overall efficiency on bio-refinery. The molecular weights (Mw) of the extracted LCCs were measured by gel permeation chromatography. From the chromatograms, it was observed that the materials that were subjected to pre-processing prior to further processing, the Mw shifted to lower Mws regions. It was found that LCCs isolated from mild alkali pre-extracted pulps had high lignin syringyl to guaiacyl lignin contents than LCCs isolated from dilute acid pre-extracted pulps. High syringyl/guaiacyl ratio (S/G ratio) was an indication of low lignin content as a result of processing which will result to high product yields after downstream processing. The 5 average S/G ratio for the pulps from E. grandis and sugarcane bagasse was ranging between 1.1 to 19.01 and 1.4 to 18.16 respectively, while for the WIS-material generated from ionic liquid fractionated and steam exploded materials ranged from 3.29 to 9.27 and 3.5 to 13.3 respectively. The S/G ratios of the LCCs extracted from E. grandis and sugarcane bagasse pulps ranged from 0.42 to 2.39 and 0.041 to 0.31 was respectively while for the LCCs extracted from water-insoluble-solids (WIS) material generated from steam exploded material was from 4.87 to 10.40. The determination of S/G ratio is recommended for the LCC extraction and characterisation study as an evaluation of residual lignin in processed materials such as pulps and WIS. The obtained saccharifications were low, possibly due to the severity of the steam explosion pre-treatment and ionic liquid fractionation conditions which resulted on high accumulation of acetic acid and increased in cellulose crystallinity respectively. From quantitative analysis of the LCCs perspective it could be concluded that free lignin was present in mild alkali pre-extracted pulps than for the dilute acid pre-extracted pulps. / AFRIKAANSE OPSOMMING: Cellulose materiaal is saamgestel uit drie groot makromolekule komponente naamlik, sellulose, hemisellulose en lignien. Hierdie komponente is chemies verwante en direk met mekaar verbind deur kovalente binding wat wetenskaplik aangedui as lignien-koolhidraat komplekse (LCCs) en hul interaksie is fundamenteel belangrik as hout vorming en reaktiwiteit tydens chemiese en biologiese verwerking bv om te verstaan verpulping en ensiematiese hidrolise. Die vereniging van lignien met polisakkariede (kovalente verbindings) is omring deur teenstrydighede en omstredenheid in verskeie hout chemie studies. Hierdie skakeling bestaan in cellulose materiaal uit hout te kruidagtige plante. In houtagtige plante, hulle bestaan uit ester en eter bindings deur suiker hidroksiel te α-karboniel van feniel-propaan eenheid op lignien. Maar in kruidagtige plante ferulic en p-coumaric sure veresterd te hemisellulose en lignien onderskeidelik. In onlangse studies, het die bestaan van die bande is getoon deur die toepassing van indirekte analise strategieë wat gelei tot lae opbrengste en kontaminasie. Die algemene doel van die huidige studie was om te isoleer en fraksioneer LCCs van rou cellulose materiaal (E. grandis en suikerriet bagasse) en die ooreenstemmende verwerkte materiaal (chemiese pulp en water-oplosbare residue (WIS)) ten einde die chemiese struktuur van die te bepaal oorblywende lignien wat verband hou met polisakkariede en hoe hulle geaffekteerde industriële verwerking. Die doel van die studie is 'n dokument op te stel dat wanneer die ontwikkeling van verpulping en bio-etanol bio-raffinadery sal grootliks afhang van die gedetailleerde hout chemie oor hoe om die komponente met mekaar voor en na hemisellulose pre-onttrekking voor verpulping en stoom ontploffing pre-behandeling voor ensiematiese hidrolise. Die huidige studie was die fokus op die begrip van die effek LCCs geïsoleerd van twee verskillende industriële verwerking, maw verpulping en ensiematiese hidrolise (EH). Daar was twee lignocelluloses voerstowwe gebruik vir verpulping, dws Eucalyptus grandis en suikerriet bagasse terwyl suikerriet bagasse was die enigste grondstof gebruik vir ensiematiese hidrolise. Hemisellulose pre-onttrek (ligte alkali of verdunde suur en autohydrolysis vir suikerriet bagasse) pulp van Kraft of soda AQ van E. grandis en suikerriet bagasse is gebruik om die effek van Xylan pre-onttrekking te voor verstaan verpulping op lignien-koolhidraat komplekse het nie aan die berig is beste kennis van die primêre outeur. Ook voor EH die materiaal is onderworpe aan twee verskillende behandeling metodes, naamlik stoom ontploffing en ioniese vloeistof fraksionering in wisselende toestande. Die studie geïllustreer die tipes onttrek en gefractioneerd LCCs van hemisellulose pre-onttrek pulp en WIS in vergelyking met die nie-onttrek pulp en verslae van die literatuur. Lignien-koolhidraat komplekse (LCCs) is geïsoleer en gefraksioneer deur 'n anorganiese metode wat redelike kwantifisering hoeveelhede en geen besoedeling en lae opbrengste opgelewer vir die hardehout vergelyking met verslae van die gebruik van 'n ensiematiese metode. Na die beste kennis van die skrywers, het geen werk op WIS materiaal gedoen. Die lignocelluloses is onderworpe aan die bal maal wat gevolg is deur 'n reeks van anorganiese oplosmiddels swelling en ontbinding in 2 breuke dws glucan-lignien en Xylan-lignien-glucan. Karakterisering van die geïsoleerde LCCs is gemaak met behulp van 'n verskeidenheid van analitiese gereedskap soos FTIR-PCA, HPLC, GPC en GC-MS. LCCs was duidelik wanneer FTIR en HPLC studies is uitgevoer. Residuele lignien geïsoleerd van die lignocelluloses is aanvaar moet word chemies gebind aan koolhidrate en meestal te xylan. Ongeveer 60% en 30% van die lignien is gekoppel aan xylan terwyl dit vir die tweede en eerste breuke onderskeidelik. Dit is gerapporteer dat lignien wat verband hou met Xylan is meer bestand en die delignification proses as wanneer gekoppel aan glucane wat maklik hidroliseerbare verminder. Met die FTIR en GPC ontledings van LCC breuke, was dit duidelik dat die ester bande van LCCs is deur pre-ontginning en pre-behandeling, waar dit gelei tot meer sellulose om meer toeganklik te alkaliese verpulping en ensiematiese hidrolise onderskeidelik vernietig. Die skakeling is óf gedeeltelik afgebreek of heeltemal vernietig lei tot beduidende veranderinge van chemiese strukture. Die polydispersity van die LCCs bygestaan in die bepaling van die struktuur van lignien, hetsy bestaande as monolignols op die oppervlak van die vesel of 'n as komplekse twee of drie-dimensionele struktuur wat gekoppel is aan koolhidrate as die Mw vermeerder of verminder. In die algemeen, kan hierdie bevindinge het 'n belangrike implikasie vir die algehele doeltreffendheid op bio-raffinadery. Die molekulêre gewigte (Mw) die onttrek LCCs gemeet deur gelpermeasie- chromatografie. Van die chromatograms, was dit opgemerk dat die materiaal wat blootgestel is aan die pre-verwerking voor verdere verwerking, die Mw verskuif MWS streke te verlaag. Daar is gevind dat LCCs geïsoleerd van ligte alkali pre-onttrek pulp het hoë lignien syringyl lignien inhoud as LCCs geïsoleerd van verdunde suur vooraf onttrek pulp te guaiacyl. Hoë syringyl / guaiacyl verhouding (S/G-verhouding) was 'n aanduiding van 'n lae lignien inhoud as 'n resultaat van verwerking wat sal lei tot 'n hoë produk opbrengste ná stroomaf verwerking. Die gemiddelde S/G-verhouding vir die pulp van E. grandis en suikerriet bagasse was wat wissel tussen 1,1-19,01 en 1,4-18,16 onderskeidelik, terwyl dit vir die WIS-materiaal gegenereer uit ioniese vloeistof gefraksioneer en stoom ontplof materiaal het gewissel 3,29-9,27 en 3.5 13,3 onderskeidelik. Die S/G verhoudings van die LCCs onttrek uit E. grandis en suikerriet bagasse pulp gewissel 0,42-2,39 en ,041-,31 was onderskeidelik terwyl dit vir die LCCs onttrek uit water-oplosbare-vastestowwe (WIS) materiaal gegenereer uit stoom ontplof materiaal was van 4,87-10,40. Die bepaling van S/G-verhouding word aanbeveel vir die LCC ontginning en karakterisering studie as 'n evaluering van die oorblywende lignien in verwerkte materiaal soos pulp en WIS. Die verkry saccharifications was laag, moontlik as gevolg van die erns van die stoom ontploffing pre-behandeling en ioniese vloeistof fraksionering voorwaardes wat gelei op 'n hoë opeenhoping van asynsuur en vermeerder in sellulose kristalliniteit.