In this study, the effect of the addition of hyaluronic acid (HA) on bacterial cellulose (BC) production, under static conditions was evaluated in terms of the properties of the resulting BC hybrid ...membranes. HA was added to the fermentation process in three distinct time points: first day (BC-T0), third day (BC-T3) and sixth day (BC-T6). Analyses of FT-IR and CP/MAS 13C NMR confirmed the presence of HA in bacterial cellulose membranes. The crystal structure, crystallinity index (Ic) surface roughness, thermal stability and hybrophobic/hydrophilic character changed. Membranes with higher roughness were produced with HA added on the first and third day of fermentation process. The surface energy of BC/HA membranes was calculated and more hydrophilic membranes were produced by the addition of HA on the third and sixth day, also resulting in more thermally stable materials. The results demonstrate that bacterial cellulose/hyaluronic acid hybrid membranes can be produced in situ and suggest that HA interacts with the sub-elementary bacterial cellulose fibrils, changing the properties of the membranes. The study and understanding of the factors that affect those properties are of utmost importance for the safe and efficient use of BC as biomaterials in numerous applications, specifically in the biological field.
Despite the great properties of bacterial cellulose, its manufacture is still limited due to difficulties in large-scale production. These problems are mainly related to low production yields and ...high overall costs of the conventional culture media normally used. To surpass these problems, it is necessary to identify new cheap and sustainable carbon sources. Thus, this work aims to isolate and select a high cellulose-producing
strain from vinegar industry, and study its potential for bacterial cellulose synthesis in an industrial soybean co-product, known as soybean molasses, used as fermentation medium.
One isolated strain was able to produce high amount of cellulose in the standard Hestrin-Schramm medium, so we tested its ability to produce this biopolymer in a soybean molasses medium. The characteristics and properties of the produced bacterial cellulose membranes were analyzed by thermogravimetric analysis, X-ray diffraction, infrared spectroscopy, water-holding capacity and rehydration ratio. Genetic analysis of the selected strain served to determine its genus and species.
An isolated strain that produced the highest amount of cellulose in Hestrin-Schramm medium (3.7 g/L) was genetically identified as
V-05. This strain produced 10.0 g/L of cellulose in soybean molasses medium. Membranes from both substrates had similar chemical structure, crystallinity and thermal degradation. Soybean molasses proved to be a suitable alternative medium for biosynthesis of cellulose in comparison with the standard medium. In addition to providing higher production yield, the membranes showed great structural characteristics, similar to those obtained from standard medium.
In this research, we have isolated and identified a
strain which exhibits a high capacity for cellulose production in soybean molasses. The isolation and selection of strains with high capacity for microbial metabolite production is important for decreasing bioprocess costs. Furthermore, as there is a necessity today to find cheaper carbon sources to obtain microbial products at a lower cost, soybean molasses represents an interesting alternative medium to produce bacterial cellulose for its industrial application.
The cellulose from Komagataeibacter hansenii is synthesized as a thin film at the surface of glucose based media. Strong acid hydrolysis release sections of crystalline cellulose chains in nanometric ...scale that leads to persistent suspensions in water. The cellulose anhydro-glucose hydroxyls are suitable to receive functional groups as enzymes, and lipases have great economic value being a valuable model for protein immobilization. In this work both, the membrane of bacterial cellulose as well the nanocellulose produced trough acid hydrolysis, was functionalized with a lipase. The bacterial cellulose membranes were produced by Hestrin-Schramm medium, and nanocelluloses produced from the pristine material was characterized using techniques as 13C solid state NMR and transmission electron microscopy (TEM). The pristine membranes and nanocellulose were functionalized with succinic acid as linker, then lipase was conjugated using EDC (N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride), and NHS (N-Hydroxysuccinimide). The effectiveness of the chemical process was characterized, and the lipase activity were measured. The presence of the succinic acid and amide linkage, as well physicalchemical changes on the functionalized polysaccharide. Hence, we inferred that after immobilization the enzyme maintained its activity in both cellulose and the cellulose membrane.
Surfactants represent a billionaire market of amphiphilic molecules with worldwide applications in almost every branch of modern industry. The most common surfactants, available and currently used, ...are chemically produced. However, there is an urge to replace these chemical compounds with those obtained by mild and green technologies such as microbial biosurfactants produced by fermentative processes. Rhamnolipids are glycolipid biosurfactants that present highly effective surface-active properties and enormous market potential; nevertheless, their production costs remain not competitive. Here, we present a process of rhamnolipid production by static submerged cultivation using membranes of bacterial cellulose as substrate. The mixture of the rhamnolipid congeners was characterized showing effective surface-active properties and high amount of di-rhamnolipids (95.6%). Through this fermentative technology, 15.8 g/L of rhamnolipid was reach using a very simple and low-cost medium. The present process might decrease biosurfactant production cost, avoid foam formation, and finally make rhamnolipid production more viable.
•The enzymatic extraction was able to recover crystalline low molar mass hyaluronic acid (HA) from chicken comb, that was also identified and characterized by FT-IR and 13C CP MAS solid state nmr, ...and thermal stability by thermogravimetry.•Hyaluronic acid was successfully incorporated on to bacterial cellulose membranes characterized by FT-IR and 13C CP MAS solid state nmr, and thermal stability by thermogravimetry, as well by atomic force microscopy and scanning electron microscopy.•The hyaluronic acid incorporated lowers the crystallinity of cellulose, but the hyaluronic acid that is incorporated on to membrane is crystalline, specially for the membrane obtained when the HA is added to fermentation on to third day.
The bacterial cellulose (BC), from Gluconacetobacter hansenii, is a biofilm with a high degree of crystallinity that can be used for therapeutic purposes and as a candidate for healing wounds. Hyaluronic acid (HA) is a constitutive polysaccharide found in the extracellular matrix and is a material used in tissue engineering and scaffolding for tissue regeneration. In this study, polymeric composites were produced in presence of hyaluronic acid isolated from chicken comb on different days of fermentation, specifically on the first (BCHA-SABT0) and third day (BCHA-SABT3) of fermentation. The structural characteristics, thermal stability and molar mass of hyaluronic acid from chicken comb were evaluated. Native membrane and polymeric composites were characterized with respect to their morphology and crystallinity. The optimized process of extraction and purification of hyaluronic acid resulted in low molar mass hyaluronic acid with structural characteristics similar to the standard commercial hyaluronic acid. The results demonstrate that the polymeric composites (BC/HA-SAB) can be produced in situ. The membranes produced on the third day presented better incorporation of HA-SAB between cellulose microfiber, resulting in membranes with higher thermal stability, higher roughness and lower crystallinity. The biocompatiblily of bacterial cellulose and the importance of hyaluronic acid as a component of extracellular matrix qualify the polymeric composites as promising biomaterials for tissue engineering.
Bacterial cellulose membrane is a biomaterial with high value in the biomedical field. Many groups have been making efforts to promote chemical modifications of its structure and, consequently, add ...new characteristics. Recently, our group has developed a methodology to insert monoester succinic acid in bacterial cellulose membrane without disrupting the microfibril network and bind a protein on it. Considering the role of carbohydrates in the molecular recognition process in biological events, we continued these studies by inserting covalently multiples copies of aryl monosaccharide to bacterial cellulose succinylated and to study the in vitro tissue compatibility using fibroblasts. The mix of synthetical chemistry and material modification was performed to prepare aminoaryl mannoside and conjugate it, via amide bond using ultrasonic irradiation, to succinic group of bacterial cellulose. This material was characterized chemically (IR, UV–vis, 13C NMR CP-MAS) and physically (TGA and AFM). Mannosylated cellulose showed good in vitro compatibility with fibroblasts demonstrating its potential in the tissue engineering field which could provide a tissue compatible scaffold.
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•Cellulose surface is decorated with multiples copies of mannosides•Coupling reaction is possible under ultrasound irradiation•Mannosylated modified cellulose shows enhanced compatibility with fibroblast grow
Pozadina istraživanja. Usprkos izvrsnim svojstvima bakterijske celuloze, njezina je proizvodnja još uvijek ograničena zbog poteškoća u provođenju proizvodnje na veliko, uglavnom zbog niskog prinosa i ...visokih troškova uzgoja u uobičajeno korištenim podlogama. Da bi se ti problemi zaobišli, potrebno je pronaći nove jeftine i održive izvore ugljika. Stoga je svrha ovoga rada bila tijekom postupka proizvodnje octa izolirati i odabrati soj bakterije Komagataeibacter koji može proizvesti velike količine celuloze, te ispitati njegovu sposobnost sinteze bakterijske celuloze u podlozi od sojine melase, jednom od nusproizvoda industrijskog uzgoja soje.
Eksperimentalni pristup. Jedan je od izoliranih sojeva proizveo veliku količinu celuloze u standardnoj Hestrin-Schramm podlozi, pa smo ispitali može li proizvesti taj biopolimer i u podlozi od sojine melase. Glavne značajke i svojstva dobivene bakterijske celuloze ispitane su termogravimetrijskom analizom, rentgenskom difrakcijom, infracrvenom spektroskopijom, te mjerenjem sposobnosti vezanja vode i stupnja rehidracije. Genetičkom su analizom određeni rod i vrsta izoliranog soja bakterije.
Rezultati i zaključci. Soj bakterije koji je proizveo najviše celuloze u Hestrin-Schramm podlozi (3,7 g/L) genetičkom je analizom identificiran kao Komagataeibacter intermedius V-05. U podlozi sa sojinom melasom taj je soj proizveo 10,0 g/L celuloze. Celulozne membrane dobivene uzgojem bakterije u obje podloge imale su sličnu kemijsku strukturu, podjednako svojstvo kristaliničnosti i sličnu toplinsku stabilnost. Sojina melasa pokazala se kao dobra alternativna standardnoj podlozi za biosintezu celuloze. Osim što je pomoću nje dobiven veći prinos celuloze, struktura dobivenih membrana bila je izuzetno dobra, slična membranama dobivenim uzgojem u standardnoj podlozi.
Novina i znanstveni doprinos. U ovom smo radu izolirali i identificirali soj bakterije Komagataeibacter koji može uspješno proizvesti celulozu u podlozi od sojine melase. Izolacija i odabir sojeva koji mogu proizvesti velike količine mikrobnih metabolita vrlo su važni za smanjenje troškova bioprocesa. Uz to, budući da je u današnje vrijeme neophodno pronaći ekonomičnije izvore ugljika za jeftiniju proizvodnju mikrobnih proizvoda, sojina melasa predstavlja zanimljivu alternativu uobičajenoj podlozi za industrijsku proizvodnju bakterijske celuloze.
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