bacterial cellulose

细菌纤维素
  • 文章类型: Journal Article
    包装的高消耗导致了大量的废物产生,尤其是难以回收的不可生物降解的聚合物形式。微生物纤维素被认为是可生物降解的,低成本,有用的,生态正确的聚合物,可以与其他生物材料连接,以获得新的特性,因此,用作生产包装的原料。Bagasse,富含植物纤维素的废物,可以再加工并用于生产和增强其他材料。基于这些概念,当前研究的目的是设计由细菌纤维素(BC)和甘蔗渣(SCB)组成的可持续包装材料,采用创新的切碎和重建方法,能够避免生物质废物。这种方法可以创建一个具有0.10厘米恒定厚度的均匀结构,被归类为具有高克重。开发的材料,特别是0.7BC/0.3SCB[70%(w/w)BC加30%(w/w)SCB]复合材料,具有相当大的抗拉强度(高达46.22MPa),这几乎是单独SCB的三倍(17.43兆帕)。此外,0.7BC/0.3SCB复合材料的吸附指数(235.85±31.29s)比SCB(0.78±0.09s)高约300倍。该包装材料还接受了其他分析测试,以确定其物理和化学特性,这表明它具有优异的柔韧性,可以折叠100次而不撕裂。通过扫描电子显微镜探索了它的表面,这表明存在直径为83.18nm(BC)的纤维。在重构过程后观察到更大的粘附性,甚至在BC基质中观察到SCB纤维的均匀分布。导致比纯净形式的SCB更大的抗撕裂性。结果表明,由BC和SCB形成的复合材料有望作为可持续包装的原料,由于其阻力和均匀性。
    The high consumption of packaging has led to a massive production of waste, especially in the form of nonbiodegradable polymers that are difficult to recycle. Microbial cellulose is considered a biodegradable, low-cost, useful, ecologically correct polymer that may be joined with other biomaterials to obtain novel characteristics and can, therefore, be used as a raw material to produce packaging. Bagasse, a waste rich in plant cellulose, can be reprocessed and used to produce and reinforce other materials. Based on these concepts, the aim of the current research was to design sustainable packaging material composed of bacterial cellulose (BC) and sugarcane bagasse (SCB), employing an innovative shredding and reconstitution method able to avoid biomass waste. This method enabled creating a uniform structure with a 0.10-cm constant thickness, classified as having high grammage. The developed materials, particularly the 0.7 BC/0.3 SCB [70% (w/w) BC plus 30% (w/w) SCB] composite, had considerable tensile strength (up to 46.22 MPa), which was nearly thrice that of SCB alone (17.43 MPa). Additionally, the sorption index of the 0.7 BC/0.3 SCB composite (235.85 ± 31.29 s) was approximately 300-times higher than that of SCB (0.78 ± 0.09 s). The packaging material was also submitted to other analytical tests to determine its physical and chemical characteristics, which indicated that it has excellent flexibility and can be folded 100 times without tearing. Its surface was explored via scanning electron microscopy, which revealed the presence of fibers measuring 83.18 nm in diameter (BC). Greater adherence after the reconstitution process and even a uniform distribution of SCB fibers in the BC matrix were observed, resulting in greater tear resistance than SCB in its pure form. The results demonstrated that the composite formed by BC and SCB is promising as a raw material for sustainable packaging, due to its resistance and uniformity.
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  • 文章类型: Journal Article
    在生物工程中使用天然来源的生物材料导致了农林业的创新方法。细菌纤维素(BC),与植物来源的纤维素(PC)具有相同的化学式,表现出明显不同的生化特性,包括高度的结晶度和优越的保水能力。先前的研究表明,天然来源的基于葡萄糖的几丁质可增强草本植物和非草本植物的植物生长。在这项研究中,我们在实验室生产了BC,并研究了其对基质和茄子幼苗的影响。与未经处理的幼苗相比,用BC改良的土壤增加了根的生长。此外,在有限的灌溉条件下,BC增加了全球发育参数,包括鲜重和干重,以及总碳和氮含量。在非灌溉条件下,BC对植物的存活有很大贡献。对BC处理的幼苗进行RNA测序(Illumina®)显示BC,尽管它的细菌起源,没有给植物带来压力,确认其无害的性质,它轻微诱导与根发育和细胞分裂相关的基因,以及抑制应激反应和防御。有机基质中BC的存在增加了土壤中磷(P)的有效性,铁(Fe),和钾(K),与植物营养吸收增强有关。我们的结果表明,BC具有改善土壤养分利用率和植物对低灌溉的耐受性的潜力,在全球变暖的背景下,使其对农业和林业有价值。
    The use of natural-origin biomaterials in bioengineering has led to innovative approaches in agroforestry. Bacterial cellulose (BC), sharing the same chemical formula as plant-origin cellulose (PC), exhibits significantly different biochemical properties, including a high degree of crystallinity and superior water retention capacity. Previous research showed that natural-origin glucose-based chitin enhanced plant growth in both herbaceous and non-herbaceous plants. In this study, we produced BC in the laboratory and investigated its effects on the substrate and on Solanum lycopersicum seedlings. Soil amended with BC increased root growth compared with untreated seedlings. Additionally, under limited irrigation conditions, BC increased global developmental parameters including fresh and dry weight, as well as total carbon and nitrogen content. Under non-irrigation conditions, BC contributed substantially to plant survival. RNA sequencing (Illumina®) on BC-treated seedlings revealed that BC, despite its bacterial origin, did not stress the plants, confirming its innocuous nature, and it lightly induced genes related to root development and cell division as well as inhibition of stress responses and defense. The presence of BC in the organic substrate increased soil availability of phosphorus (P), iron (Fe), and potassium (K), correlating with enhanced nutrient uptake in plants. Our results demonstrate the potential of BC for improving soil nutrient availability and plant tolerance to low irrigation, making it valuable for agricultural and forestry purposes in the context of global warming.
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  • 文章类型: Journal Article
    以多层氧化石墨烯(GO)为改性剂,以细菌纤维素为骨架,通过超声振荡工艺合成了三维多孔细菌纤维素/氧化石墨烯(BC/GO)复合水凝胶(BC/GO),有效吸收铅离子。通过TEM研究了BC/GO的特性,SEM,FT-IR,NMR和Zeta电位实验。与细菌纤维素相比,超声波方法和来自GO的羧基有助于提高BC中O(3)H的可用性,除了更松散的三维结构和富集的含氧基团,导致对Pb(II)的吸附能力显着提高。在本文中,BC/GO的吸附行为受GO浓度的影响,吸附时间,和初始浓度。本研究中发现的BC/GO对Pb(II)的最高吸附容量为224.5mg/g。研究结果表明,伪二阶模型解释了BC/GO吸附动力学,其吸附等温线数据符合Freundlich模型。因为立体结构比较松散,羧基的络合,以及O(3)H的增强可用性,细菌纤维素表现出更好的吸附能力。
    A three-dimensional porous bacterial cellulose/graphene oxide (BC/GO) composite hydrogel (BC/GO) was synthesized with multi-layer graphene oxide (GO) as the modifier and bacterial cellulose as the skeleton via an ultrasonic shaking process to absorb lead ions effectively. The characteristics of BC/GO were investigated through TEM, SEM, FT-IR, NMR and Zeta potential experiments. Compared to bacterial cellulose, the ultrasonic method and the carboxyl groups stemming from GO helped to enhance the availability of O(3)H of BC, in addition to the looser three-dimensional structure and enriched oxygen-containing groups, leading to a significantly higher adsorption capacity for Pb(II). In this paper, the adsorption behavior of BC/GO is influenced by the GO concentration, adsorption time, and initial concentration. The highest adsorption capacity for Pb(II) on BC/GO found in this study was 224.5 mg/g. The findings implied that the pseudo-second-order model explained the BC/GO adsorption dynamics and that the data of its adsorption isotherm fit the Freundlich model. Because of the looser three-dimensional structure, the complexation of carboxyl groups, and the enhanced availability of O(3)H, bacterial cellulose exhibited a much better adsorption capacity.
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  • 文章类型: Journal Article
    本研究的目的是开发一种基于细菌纤维素(BC)中的红白菜提取物(RCE)固定化的pH感应生物聚合物膜,以检测黄瓜中的污染和γ辐射暴露。获得的结果表明,对于水性形式的RCE以及掺入BC膜(RCE-BC)中的RCE,对pH变化具有敏感性。两者均显示与细菌生长相关的颜色变化(R2=0.91),pH值从2增加到12(R2=0.98)支持了这一点。RCE和RCE-BC暴露于γ辐射(0、2.5、5、10、15、20、25kGy)导致颜色逐渐降低,这在RCE水性样品中更为明显。为了感知黄瓜的细菌污染,在冷藏条件下进行0、5、10和15天的总计数,发现未辐照和2kGy辐照样品分别达到9.13和5.47logcfu/mL,分别。在整个储存期间检测到的主要分离株被鉴定为荧光假单胞菌,Erwiniasp.使用基质辅助激光解吸电离-飞行时间-ms(MALDI-TOF-MS)的泛菌团聚体。通过在储存的5和10天内的颜色变化检测到储存的辐照黄瓜中的细菌生长,之后没有明显的变化。这是非常有用的,因为在储存早期的污染不能用肉眼感测到。这项研究首次强调利用RCE和RCE-BC作为智能食品包装的生态友好型pH传感指示剂膜,以检测冰箱储存的黄瓜的食品污染和伽马保存。
    The aim of the present study is to develop a pH-sensing biopolymer film based on the immobilization of red cabbage extract (RCE) within bacterial cellulose (BC) to detect contamination and gamma radiation exposure in cucumbers. The results obtained show a sensitivity to pH changes for RCE in its aqueous form and that incorporated within BC films (RCE-BC), both showed color change correlated to bacterial growth (R2 = 0.91), this was supported with increase in pH values from 2 to 12 (R2 = 0.98). RCE and RCE-BC exposure to gamma radiation (0, 2.5, 5, 10, 15, 20, 25 kGy) resulted in gradual decrease in color that was more evident in RCE aqueous samples. To sense bacterial contamination of cucumbers, the total count was followed at 0, 5, 10 and 15 days in cold storage conditions and was found to reach 9.13 and 5.47 log cfu/mL for non-irradiated and 2 kGy irradiated samples, respectively. The main isolates detected throughout this storage period were identified as Pseudomonas fluorescens, Erwinia sp. Pantoea agglomerans using matrix assisted laser desorption ionization-time of flight-ms (MALDI-TOF-MS). Bacterial growth in stored irradiated cucumbers was detected by color change within 5 and 10 days of storage, after which there was no evident change. This is very useful since contamination within the early days of storage cannot be sensed with the naked eye. This study is the first to highlight utilizing RCE and RCE-BC as eco-friendly pH-sensing indicator films for intelligent food packaging to detect both food contamination and gamma preservation for refrigerator stored cucumbers.
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  • 文章类型: Journal Article
    本研究探索了丝瓜海绵(LS)在增强乙酸化过程中的利用。LS以具有高孔隙率和比表面积而闻名,并可以提供一种支持乙酸细菌(AAB)生长的新手段,以提高生物量产量和乙酸化率,从而促进更高效和可持续的食醋生产。此外,LS和涂有κ-角叉菜胶(LSK)的丝瓜海绵的有前途的潜力意味着它们可能代表着共同生产具有工业价值的生物产品的有效替代品,例如细菌纤维素(BC)和乙酸。
    LS和LSK在浸没式半连续乙酸化过程中用作巴氏醋杆菌UMCC2951的吸附剂。实验是在1Hz和32℃的温度下往复摇动下进行的。根据细胞干重(CDW)评估了两种系统(分别为LS-AAB和LSK-AAB)的性能,酸化率,和BC生物膜的形成。
    使用LS显著提高了醋化过程中的生物量产量,与浮游细胞获得的0.91mg/L相比,CDW为3.34mg/L。用κ-角叉菜胶涂覆LS进一步提高了产量,CDW为4.45mg/LLSK-AAB系统的固化率也较高,达到3.33±0.05g/Ld,而LS-AAB为2.45±0.05g/Ld,浮游细胞为1.13±0.05g/Ld。此外,在第二个操作周期中,BC生物膜的形成在LSK-AAB系统中更为明显(37.0±3.0mg/L,与LS-AAB中的25.0±2.0mg/L相反)。
    这项研究表明,LS显着提高了乙酸化过程的效率,特别是用κ-角叉菜胶增强时。生物量产量的增加,加速乙化,增强的BC生物膜形成突出了LS-AAB系统的潜力,尤其是LSK-AAB变体,在可持续和有效的食醋生产中。这些系统为小规模,符合生态友好做法并满足专门市场需求的半连续乙化工艺。最后,这种创新的方法促进了乙酸和细菌纤维素的双重生产,在生物技术领域具有潜在的应用。
    UNASSIGNED: This study explored the utilization of luffa sponge (LS) in enhancing acetification processes. LS is known for having high porosity and specific surface area, and can provide a novel means of supporting the growth of acetic acid bacteria (AAB) to improve biomass yield and acetification rate, and thereby promote more efficient and sustainable vinegar production. Moreover, the promising potential of LS and luffa sponge coated with κ-carrageenan (LSK) means they may represent effective alternatives for the co-production of industrially valuable bioproducts, for example bacterial cellulose (BC) and acetic acid.
    UNASSIGNED: LS and LSK were employed as adsorbents for Acetobacter pasteurianus UMCC 2951 in a submerged semi-continuous acetification process. Experiments were conducted under reciprocal shaking at 1 Hz and a temperature of 32 °C. The performance of the two systems (LS-AAB and LSK-AAB respectively) was evaluated based on cell dry weight (CDW), acetification rate, and BC biofilm formation.
    UNASSIGNED: The use of LS significantly increased the biomass yield during acetification, achieving a CDW of 3.34 mg/L versus the 0.91 mg/L obtained with planktonic cells. Coating LS with κ-carrageenan further enhanced yield, with a CDW of 4.45 mg/L. Acetification rates were also higher in the LSK-AAB system, reaching 3.33 ± 0.05 g/L d as opposed to 2.45 ± 0.05 g/L d for LS-AAB and 1.13 ± 0.05 g/L d for planktonic cells. Additionally, BC biofilm formation during the second operational cycle was more pronounced in the LSK-AAB system (37.0 ± 3.0 mg/L, as opposed to 25.0 ± 2.0 mg/L in LS-AAB).
    UNASSIGNED: This study demonstrates that LS significantly improves the efficiency of the acetification process, particularly when enhanced with κ-carrageenan. The increased biomass yield, accelerated acetification, and enhanced BC biofilm formation highlight the potential of the LS-AAB system, and especially the LSK-AAB variant, in sustainable and effective vinegar production. These systems offer a promising approach for small-scale, semi-continuous acetification processes that aligns with eco-friendly practices and caters to specialized market needs. Finally, this innovative method facilitates the dual production of acetic acid and bacterial cellulose, with potential applications in biotechnological fields.
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  • 文章类型: Journal Article
    细菌纤维素是一种具有独特大分子结构的生物相容性生物材料。与植物来源的纤维素不同,细菌纤维素是由某些细菌产生的,产生由具有高结晶度的自组装纳米结构纤维组成的可持续材料。由于它的纯度,细菌纤维素对生物医学应用具有吸引力,并引起了越来越多的兴趣,特别是在3D打印用于组织工程和再生医学应用的背景下。细菌纤维素可以作为3D打印中的优秀生物墨水,由于其生物相容性,生物降解性,以及模拟结缔组织的细胞外基质(ECM)的胶原纤维的能力。它的纳米纤丝结构为细胞附着提供了合适的支架,扩散,和差异化,对组织再生至关重要。此外,其机械强度和灵活性允许复杂的组织结构的精确打印。细菌纤维素本身没有抗菌活性,但是由于其理想的结构,它作为其他生物活性分子的基质,产生具有抗菌特性的混合产品,特别有利于慢性伤口愈合过程的管理。总的来说,这种独特的特性组合使细菌纤维素成为制造水凝胶和3D打印支架的有前途的材料,推进组织工程和再生医学领域。
    Bacterial cellulose is a biocompatible biomaterial with a unique macromolecular structure. Unlike plant-derived cellulose, bacterial cellulose is produced by certain bacteria, resulting in a sustainable material consisting of self-assembled nanostructured fibers with high crystallinity. Due to its purity, bacterial cellulose is appealing for biomedical applications and has raised increasing interest, particularly in the context of 3D printing for tissue engineering and regenerative medicine applications. Bacterial cellulose can serve as an excellent bioink in 3D printing, due to its biocompatibility, biodegradability, and ability to mimic the collagen fibrils from the extracellular matrix (ECM) of connective tissues. Its nanofibrillar structure provides a suitable scaffold for cell attachment, proliferation, and differentiation, crucial for tissue regeneration. Moreover, its mechanical strength and flexibility allow for the precise printing of complex tissue structures. Bacterial cellulose itself has no antimicrobial activity, but due to its ideal structure, it serves as matrix for other bioactive molecules, resulting in a hybrid product with antimicrobial properties, particularly advantageous in the management of chronic wounds healing process. Overall, this unique combination of properties makes bacterial cellulose a promising material for manufacturing hydrogels and 3D-printed scaffolds, advancing the field of tissue engineering and regenerative medicine.
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  • 文章类型: Journal Article
    Natadecoco,可食用的细菌纤维素(BC)产品,是在椰子水中发酵的传统甜点。通过预发酵的椰子水增强了Komagataeibacternataicola对Natadecoco的生产,但是它的不稳定性是一个挑战。这里,通过塑造椰子水的代谢物谱,酿酒酵母84-3显着改善了纳塔科拉Y19的BC产量。酿酒酵母84-3的不同发酵时间导致不同的代谢产物谱和对BC产量的不同促进作用。与未发酵的椰子水相比,由酿酒酵母84-3发酵1d和7d的椰子水使BC产量提高了14.1倍和5.63倍,分别。未发酵椰子水和1d发酵椰子水之间的分析表明129种明显不同的代谢产物,包括有机酸,氨基酸,核苷酸,以及它们的衍生物。延长发酵7d改变水平的155种代谢产物属于有机酸,氨基酸,核苷酸及其衍生物。Spearman相关分析进一步显示,17种代谢物与BC产量呈正相关,21种代谢物与BC产量呈负相关。这些代谢物可能会影响能量代谢,细胞信号,膜完整性,以及K.nataicolaY19的BC生产。进一步的验证实验表明,BC的产量不仅与代谢物的类型密切相关,而且与代谢物的浓度密切相关。这项研究为利用稳定的发酵椰子水介质的高效BC发酵系统提供了新的理论框架。
    Nata de coco, an edible bacterial cellulose (BC) product, is a traditional dessert fermented in coconut water. Production of Nata de coco by Komagataeibacter nataicola is enhanced by pre-fermented coconut water, but its instability is a challenge. Here, BC production by K. nataicola Y19 was significantly improved by Saccharomyces cerevisiae 84-3 through shaping the metabolite profile of the coconut water. Different fermentation time with S. cerevisiae 84-3 resulted in distinct metabolite profiles and different promoting effect on BC yield. Compared to unfermented coconut water, coconut water fermented by S. cerevisiae 84-3 for 1d and 7d enhanced BC yield by 14.1-fold and 5.63-fold, respectively. Analysis between unfermented coconut water and 1d-fermented coconut water showed 129 significantly different metabolites, including organic acids, amino acids, nucleotides, and their derivatives. Prolonged fermentation for 7d changed levels of 155 metabolites belongs to organic acids, amino acids, nucleotides and their derivatives. Spearman correlation analysis further revealed that 17 metabolites were positively correlated with BC yield and 21 metabolites were negatively correlated with BC yield. These metabolites may affect energy metabolism, cell signaling, membrane integrity, and BC production by K. nataicola Y19. The further verification experiment gave the view that BC yield was not only closely related to the types of metabolites but also the concentration of metabolites. This study provides a novel theoretical framework for a highly efficient BC fermentation system utilizing stable fermented coconut water mediums.
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  • 文章类型: Journal Article
    天然聚合物由于其有害影响较小,因此在更广泛的应用中得到了越来越多的应用。值得注意的是,细菌纤维素由于其特殊的物理和化学性质及其实质性的生物相容性而获得了重要的考虑,这使得它成为多种生物医学应用的有吸引力的候选者。这项研究试图彻底解开细菌纤维素前体的微观结构,被称为生物絮凝剂,迄今为止,它们的特征很差,通过采用电子和光学显微镜技术。这里,从细菌和酵母共生培养物(SCOBY)的生物絮凝剂开始,我们证明了它们的微观结构特征,如孔隙率,纤维素组装度,纤维的密度和分数,在它们朝液-气界面上升的过程中时空变化。此外,我们的研究确定了电子显微镜和光学显微镜参数之间的相关性,无需离线样品制备程序即可评估生物絮凝剂的微观结构。最终目标是确定它们作为具有可调结构特性的新型纤维素基建筑砌块材料的潜在适用性。我们的调查证实了SCOBY生物絮凝剂的能力,以独特的微观结构为特征,在微流体装置中成功组装,从而产生具有特定和有目的地设计的结构特征的纤维素片。
    Natural polymers have found increased use in a wider range of applications due to their less harmful effects. Notably, bacterial cellulose has gained significant consideration due to its exceptional physical and chemical properties and its substantial biocompatibility, which makes it an attractive candidate for several biomedical applications. This study attempts to thoroughly unravel the microstructure of bacterial cellulose precursors, known as bioflocculants, which to date have been poorly characterised, by employing both electron and optical microscopy techniques. Here, starting from bioflocculants from Symbiotic Culture of Bacteria and Yeast (SCOBY), we proved that their microstructural features, such as porosity percentage, cellulose assembly degree, fibres\' density and fraction, change in a spatio-temporal manner during their rising toward the liquid-air interface. Furthermore, our research identified a correlation between electron and optical microscopy parameters, enabling the assessment of bioflocculants\' microstructure without necessitating offline sample preparation procedures. The ultimate goal was to determine their potential suitability as a novel cellulose-based building block material with tuneable structural properties. Our investigations substantiate the capability of SCOBY bioflocculants, characterized by distinct microstructures, to successfully assemble within a microfluidic device, thereby generating a cellulose sheet endowed with specific and purposefully designed structural features.
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  • 文章类型: Journal Article
    细菌纤维素(BC)是一种以其独特的物理化学和机械属性而闻名的天然聚合物,包括显著的持水能力,结晶度和原始的纤维网络结构。虽然BC在农业领域有着广泛的应用,工业,和医学,其工业利用受到生产成本和产量限制的阻碍。在这项研究中,根瘤菌sp.从豆根中分离,并在最佳条件下系统地评估BC合成,与Komagataeibacterhansenii产生的BC进行比较分析。研究表明,根瘤菌。当提供1.5%的葡萄糖碳源和0.15%的酵母提取物氮源时,表现出最佳的BC合成。在30°C和pH6.5的静态条件下,确定了最有利于生长和BC产生的条件(2.5g/L)。使用乳链菌肽引入修饰以增强BC特性,并通过各种技术对所得的BC-Nisin复合材料进行了全面表征,包括FE-SEM,FTIR,孔隙度,肿胀,过滤,和抗菌活性评估。结果表明,根瘤菌产生的BC。显示出与K.hansenii生产的BC相当的性能。此外,BC-乳酸链球菌素复合物对大肠杆菌和铜绿假单胞菌具有显著的抑制活性。这项研究为BC的生产提供了有价值的见解,修改,并利用根瘤菌进行表征。,突出了使其在不同应用中有效的特殊属性。
    Bacterial cellulose (BC) is a natural polymer renowned for its unique physicochemical and mechanical attributes, including notable water-holding capacity, crystallinity, and a pristine fiber network structure. While BC has broad applications spanning agriculture, industry, and medicine, its industrial utilization is hindered by production costs and yield limitations. In this study, Rhizobium sp. was isolated from bean roots and systematically assessed for BC synthesis under optimal conditions, with a comparative analysis against BC produced by Komagataeibacter hansenii. The study revealed that Rhizobium sp. exhibited optimal BC synthesis when supplied with a 1.5% glucose carbon source and a 0.15% yeast extract nitrogen source. Under static conditions at 30 °C and pH 6.5, the most favorable conditions for growth and BC production (2.5 g/L) were identified. Modifications were introduced using nisin to enhance BC properties, and the resulting BC-nisin composites were comprehensively characterized through various techniques, including FE-SEM, FTIR, porosity, swelling, filtration, and antibacterial activity assessments. The results demonstrated that BC produced by Rhizobium sp. displayed properties comparable to K. hansenii-produced BC. Furthermore, the BC-nisin composites exhibited remarkable inhibitory activity against Escherichia coli and Pseudomonas aeruginosa. This study contributes valuable insights into BC\'s production, modification, and characterization utilizing Rhizobium sp., highlighting the exceptional properties that render it efficacious across diverse applications.
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  • 文章类型: Journal Article
    本研究首次合成了基于细菌来源的纤维素(细菌纤维素(BC))和植物来源的纤维素(燕麦壳纤维素(OHC))的纤维素硝酸盐(CN)共混复合材料。开发了由细菌和植物基纤维素制成的新型CNs共混复合材料,其BC与OHC的质量比为70/30、50/50和30/70,并对其进行了充分表征,并采用两种方法对初始BC和OHC进行硝化,和三种纤维素混合物:第一种方法涉及使用硫酸-硝酸混合酸(MA),而第二种方法在二氯甲烷(NAMC)存在下使用浓硝酸。发现使用这两种硝化方法获得的CN彼此不同,最值得注意的是,粘度:用NAMC硝化的样品具有927mPa·s的极高的粘度,直到形成固定的透明丙酮凝胶。无论硝化方法如何,发现来自BC的CN(CNBC)比来自OHC的CN(CNOHC)表现出更高的氮含量,12.20-12.32%vs.11.58-11.60%,分别。对于起始BC本身,使用SEM技术检测起始纤维素和它们的CN的所有纤维素共混物具有网状纤维纳米结构。使用IR光谱法检测纤维素样品及其CN具有碱性官能团。对起始纤维素样品和由此产生的CN的TGA/DTA分析表明,合成的CN样品具有高纯度,并且具有6.14-7.13kJ/g的高分解比热,证实了他们的能量密度。CNBC是一种出色的组件,具有按需充满活力的性能;特别是,它具有较高的氮含量,同时具有稳定的纳米结构。发现CNBC对稳定性有积极影响,结构,和复合材料的能量特性。CNOHC的存在可以使CNs共混复合材料更便宜。这些由细菌和植物纤维素制成的新型CNs混合复合材料在高级领域非常需要,高性能含能材料。
    Cellulose nitrates (CNs)-blended composites based on celluloses of bacterial origin (bacterial cellulose (BC)) and plant origin (oat-hull cellulose (OHC)) were synthesized in this study for the first time. Novel CNs-blended composites made of bacterial and plant-based celluloses with different BC-to-OHC mass ratios of 70/30, 50/50, and 30/70 were developed and fully characterized, and two methods were employed to nitrate the initial BC and OHC, and the three cellulose blends: the first method involved the use of sulfuric-nitric mixed acids (MAs), while the second method utilized concentrated nitric acid in the presence of methylene chloride (NA + MC). The CNs obtained using these two nitration methods were found to differ between each other, most notably, in viscosity: the samples nitrated with NA + MC had an extremely high viscosity of 927 mPa·s through to the formation of an immobile transparent acetonogel. Irrespective of the nitration method, the CN from BC (CN BC) was found to exhibit a higher nitrogen content than the CN from OHC (CN OHC), 12.20-12.32% vs. 11.58-11.60%, respectively. For the starting BC itself, all the cellulose blends of the starting celluloses and their CNs were detected using the SEM technique to have a reticulate fiber nanostructure. The cellulose samples and their CNs were detected using the IR spectroscopy to have basic functional groups. TGA/DTA analyses of the starting cellulose samples and the CNs therefrom demonstrated that the synthesized CN samples were of high purity and had high specific heats of decomposition at 6.14-7.13 kJ/g, corroborating their energy density. The CN BC is an excellent component with in-demand energetic performance; in particular, it has a higher nitrogen content while having a stable nanostructure. The CN BC was discovered to have a positive impact on the stability, structure, and energetic characteristics of the composites. The presence of CN OHC can make CNs-blended composites cheaper. These new CNs-blended composites made of bacterial and plant celluloses are much-needed in advanced, high-performance energetic materials.
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