-
1.
Synthesis and characterization of cellulose/TiO2 nanocomposite: Evaluation of in vitro antibacterial and in silico molecular docking studies.
M V, A, Harb, M, Sundaram, R
Carbohydrate polymers. 2020;:116868
Abstract
Cellulose/TiO2 nanocomposite was synthesized using coagulation in sodium hydroxide-thiourea-urea aqueous solution medium by precipitation method. This method was accomplished green and cost-effective for the fabrication of composite nanomaterials. Structure, morphology and optical properties of the nanocomposite were characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, and ultraviolet diffuse reflectance spectra respectively. XRD results showed the anatase structure of TiO2 while FESEM micrograph showed evidence of particle size ranging from 20 to 40 nm for cellulose/TiO2 nanocomposite. The Fourier transfer infrared spectroscopy investigation reveals that the TiO2 is bound to hydroxyl groups to the cellulose by hydrogen bonding. The optical energy bandgap is found to be 2.71 eV for nanocomposite from the UV-DRS. The mechanical strength of the composites gently escalated with the addition of TiO2 nanoparticles into cellulose polymer matrix. Cellulose/TiO2 nanocomposite was screened for their in vitro antibacterial activity against Staphylococcus aureus and Escherichia coli bacteria have been investigated. Additionally, the results obtained from in silico molecular docking studies confirm the interaction of nanocomposite with proteins, were in good agreement with the experimental data. This finding provides a novel and simple method for the synthesis of cellulose/TiO2 nanocomposite as functional biomaterials.
-
2.
The Effects of Irvingia gabonensis Seed Extract Supplementation on Anthropometric and Cardiovascular Outcomes: A Systematic Review and Meta-Analysis.
Lee, J, Chung, M, Fu, Z, Choi, J, Lee, HJ
Journal of the American College of Nutrition. 2020;(5):388-396
Abstract
Background: It has been hypothesized that Irvingia gabonensis can promote weight loss by increasing fatty acid breakdown and inhibiting fatty acid synthesis.Objective: We conducted a systematic review and meta-analysis to evaluate the efficacy and safety of Irvingia gabonensis seed extract supplementation on weight-related health outcomes.Methods: Literature searches were conducted in 4 databases from January 2018 to identify randomized controlled trials (RCTs) investigating the effects of Irvingia gabonensis seed extract supplementation on anthropometric measures and cardiovascular biomarkers. Two investigators independently performed abstract screenings, full-text screenings, data extraction, and risk of bias (ROB) assessments. Random effects meta-analyses were performed when 3 or more RCTs reported the same outcome.Results: Five RCTs met the eligibility criteria for this systematic review. Four of the 5 RCTs were rated as having a high ROB, and only one RCT was rated as having a low ROB. Random-effects meta-analysis of the 5 RCTs showed that a significant decrease in body weight, body fat, and waist circumference was observed in relation to Irvingia gabonensis seed extract supplementation. However, the only one low-ROB trial did not have significantly different outcomes. Meta-analysis also showed beneficial effects of Irvingia gabonensis seed extract supplementation on total cholesterol, LDL-cholesterol, HDL-cholesterol, and triglycerides. Only the low-ROB trial showed a trend of increasing HDL-cholesterol levels (net percent change = 11.61%; 95% confidence interval (CI: -6.12%, 29.34%) and decreasing triglyceride levels (net percent change = -29%; 95% CI: -76%, 19%). The reported adverse events were minor in these 5 RCTs.Conclusions: Overall efficacy of Irvingia gabonensis seed extract supplementation on weight loss seems positive but is limited due to poor methodological quality and the insufficient reporting of the clinical trials. Further high quality RCTs are needed to determine the effectiveness of Irvingia gabonensis seed extract supplement on the weight-related health outcomes.
-
3.
Combined pretreatment of sugarcane bagasse using alkali and ionic liquid to increase hemicellulose content and xylanase production.
Rashid, R, Ejaz, U, Ali, FI, Hashmi, IA, Bari, A, Liu, J, Wang, L, Fu, P, Sohail, M
BMC biotechnology. 2020;(1):64
Abstract
BACKGROUND Lignin in sugarcane bagasse (SB) hinders its utilization by microorganism, therefore, pretreatment methods are employed to make fermentable components accessible to the microbes. Multivariate analysis of different chemical pretreatment methods can aid to select the most appropriate strategy to valorize a particular biomass. RESULTS Amongst methods tested, the pretreatment by using sodium hydroxide in combination with methyltrioctylammonium chloride, an ionic liquid, (NaOH+IL) was the most significant for xylanase production by Bacillus aestuarii UE25. Investigation of optimal levels of five significant variables by adopting Box-Behnken design (BBD) predicted 20 IU mL- 1 of xylanase and experimentally, a titer of 17.77 IU mL- 1 was obtained which indicated the validity of the model. The production kinetics showed that volumetric productivity of xylanase was much higher after 24 h (833.33 IU L- 1 h- 1) than after 48 h (567.08 IU L- 1 h- 1). The extracted xylan from SB induced more xylanase in the fermentation medium than pretreated SB or commercially purified xylan. Nuclear Magnetic Resonance, Fourier transform infrared spectroscopy and scanning electron microscopy of SB indicated removal of lignin and changes in the structure of SB after NaOH+IL pretreatment and fermentation. CONCLUSION Combined pretreatment of SB with alkali and methyltrioctylammonium chloride appeared better than other chemical methods for bacterial xylanase production and for the extraction of xylan form SB.
-
4.
Effect of carboxylation cellulose nanocrystal and grape peel extracts on the physical, mechanical and antioxidant properties of konjac glucomannan films.
Tong, C, Wu, Z, Sun, J, Lin, L, Wang, L, Guo, Y, Huang, Z, Wu, C, Pang, J
International journal of biological macromolecules. 2020;:874-884
Abstract
Active bionanocomposite films were prepared by incorporating konjac glucomannan (KGM) as a matrix, with carboxylation cellulose nanocrystal (C-CNC) as a reinforcement agent and grape peel extracts (GPE) as a natural antioxidation agent. The effects of C-CNC and/or GPE addition on the structural, morphological, barrier, thermal, mechanical and antioxidant properties of the bionanocomposite films were investigated. The rheological results of film forming solutions revealed that C-CNC and GPE were well dispersed in the KGM matrix. Scanning electron micrographs observed the addition of C-CNC had little effect on the microstructure, while more roughness and unevenness were observed on the film surface and cross-section with the C-CNC and GPE. Furthermore, the water vapor barrier property and transparency of the films improved by the addition of the C-CNC and GPE. Notably, the incorporating of C-CNC or GPE significantly alter the mechanical of the KGM/C-CNC/GPE bionanocomposite films. The highest tensile strength was achieved for the KGM/GPE bionanocomposite film with 10 wt% C-CNC, indicating C-CNC and GPE had synergistic effect on enhancing the TS of KGM film. Moreover, the KGM/C-CNC/GPE films exhibited strong antioxidant activity. These results suggested that KGM/C-CNC/GPE bionanocomposite films can be used as an active food packaging for increasing shelf life of packaged foods.
-
5.
Facile synthesis of a Co/Fe bi-MOFs/CNF membrane nanocomposite and its application in the degradation of tetrabromobisphenol A.
Hou, C, Chen, W, Fu, L, Zhang, S, Liang, C, Wang, Y
Carbohydrate polymers. 2020;:116731
Abstract
In this study, a sulfate radical-advanced oxidation process (SR-AOP) was proposed by utilizing a bimetallic Co/Fe metal-organic frameworks/cellulose nanofiber membrane (Co/Fe bi-MOFs/CNF) as a catalyst for TBBPA degradation. Sulfate radicals (SO4-) and hydroxyl radicals (OH·) were generated through the activation of peroxymonosulfate (PMS) by Co/Fe bi-MOFs/CNF. Co/Fe bi-MOFs/CNF was prepared by a facile solvothermal method and vacuum filtration. CNF acted as a natural substrates material to relieve the agglomeration of loaded MOFs. Additionally the composite membranes was easily separated from the reaction solution. The properties of the composite materials and the main factors that influenced TBBPA degradation were elucidated in detail, along with the TBBPA degradation intermediates, recyclability, and TBBPA degradation pathway. Almost 100 % of TBBPA was degraded within 30 min under optimal conditions, and the rate constant was determined to be 0.764 min-1. Furthermore, the degradation rate of the composite membrane was 60 % after 4 cycles.
-
6.
High-strength, blood-compatible, and high-capacity bilirubin adsorbent based on cellulose-assisted high-quality dispersion of carbon nanotubes.
Qiao, L, Li, Y, Liu, Y, Wang, Y, Du, K
Journal of chromatography. A. 2020;:461659
Abstract
Excess bilirubin can accumulate in body organs and has serious effects on human health. In this work, a simple engineering strategy, based on cellulose-assisted high-quality dispersion of carbon nanotubes (CNTs), is proposed to produce high-performance bilirubin adsorbents. By dispersing cellulose and CNTs in NaOH/thiourea aqueous solution, a homogeneous and stable cellulose/CNTs solution is achieved. The obtained cellulose/CNTs solution is applied for the fabrication of cellulose/CNTs microspheres (CCMs), in which cellulose serves as a base material and guarantees the blood compatibility of the composite material, and CNTs contribute to the improved mechanical strength and high adsorption capacity. To further improve blood compatibility and adsorption capacity, lysine is immobilized on the CCMs. The obtained lysine-modified CCMs (LCCMs) exhibit a large surface area (171.31 m2/g) and hierarchically porous structure. Experimental results demonstrate LCCMs have high bilirubin adsorption capacity (204.12 mg/g) that is significantly higher than most of the reported adsorbents. The combination of high strength, blood compatibility, and high adsorption capacity positions the LCCMs as a promising candidate for bilirubin removal.
-
7.
Engineering of Saccharomyces cerevisiae for efficient fermentation of cellulose.
Oh, EJ, Jin, YS
FEMS yeast research. 2020;(1)
Abstract
Conversion of lignocellulosic biomass to biofuels using microbial fermentation is an attractive option to substitute petroleum-based production economically and sustainably. The substantial efforts to design yeast strains for biomass hydrolysis have led to industrially applicable biological routes. Saccharomyces cerevisiae is a robust microbial platform widely used in biofuel production, based on its amenability to systems and synthetic biology tools. The critical challenges for the efficient microbial conversion of lignocellulosic biomass by engineered S. cerevisiae include heterologous expression of cellulolytic enzymes, co-fermentation of hexose and pentose sugars, and robustness against various stresses. Scientists developed many engineering strategies for cellulolytic S. cerevisiae strains, bringing the application of consolidated bioprocess at an industrial scale. Recent advances in the development and implementation of engineered yeast strains capable of assimilating lignocellulose will be reviewed.
-
8.
Cellulose cone tip as a sorbent material for multiphase electrical field-assisted extraction of cocaine from saliva and determination by LC-MS/MS.
Sousa, DVM, Pereira, FV, Nascentes, CC, Moreira, JS, Boratto, VHM, Orlando, RM
Talanta. 2020;:120353
Abstract
A porous and hydrophilic sorbent material was used in an extraction system, assisted by electric fields, for the extraction of cocaine in saliva and subsequent determination by ultra-high-performance liquid chromatography associated with sequential triple quadrupole mass spectrometry (UHPLC-MS/MS). The cellulose-based material was characterized by scanning electron microscopy, infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction. The time and voltage variables applied in the extraction process were investigated through a Doehlert experimental design, and with the best conditions found (35min and 300 V) some validation parameters were evaluated. The established working range was 1-100 μg L-1 (R2 > 0.99), and the detection and quantification limits determined were 0.3 and 0.8 μg L-1, respectively. Recoveries from 80 to 115% and coefficient of variation ≤15 and 16% for intra-day and inter-day assays, respectively, were obtained for sample concentrations of LOQ, 5, 25, and 75 μg L-1, indicating satisfactory accuracy and precision for the proposed method. In addition, the method presented no matrix effect, and the extraction efficiency was between 56 and 70%. The results showed that the material used has adequate physicochemical characteristics and can be applied as a sorbent and electrolyte support in multiphase extractions using electric fields.
-
9.
Imaging and Analysis of the Content of Callose, Pectin, and Cellulose in the Cell Wall of Arabidopsis Pollen Tubes Grown In Vitro.
Sede, AR, Wengier, DL, Borassi, C, Estevez, JM, Muschietti, JP
Methods in molecular biology (Clifton, N.J.). 2020;:233-242
Abstract
To achieve fertilization, pollen tubes have to protect and properly deliver sperm cells through the pistil to the ovules. Pollen tube growth is a representative example of polarized growth where new components of the cell wall and plasma membrane are continuously deposited at the tip of the growing cell. The integrity of the cell wall is of fundamental importance to maintain apical growth. For this reason, pollen tube growth has become an excellent model to study the role of polysaccharides and structural cell wall proteins involved in polar cell expansion. However, quantification of structural polysaccharides at the pollen tube cell wall has been challenging due to technical complexity and the difficulty of finding specific dyes. Here, we propose simple methods for imaging and quantification of callose, pectin , and cellulose using specific dyes such as Aniline Blue, Propidium Iodide, and Pontamine Fast Scarlet 4B.
-
10.
Effect of cellulosic filler loading on mechanical and thermal properties of date palm seed/vinyl ester composites.
Nagaraj, N, Balasubramaniam, S, Venkataraman, V, Manickam, R, Nagarajan, R, Sikiru Oluwarotimi, I
International journal of biological macromolecules. 2020;:53-66
Abstract
There are numerous better applications of fibre reinforced polymer composites today, when compared with metals and alloys. Many studies have been conducted to further improve the inherent mechanical and thermal properties of the composite materials, especially with sustainable, environmental friendly, recyclable and biodegradable reinforcements. Consequently, in this current study, the composites were prepared by combining bio solid waste (date seed filler) and vinyl ester to enhance the properties of polymer composites. The date seed filler reinforced vinyl ester (DSF-VE) composites were prepared by using conventional compression moulding technique with varying fillers loadings from 5% to 50%. The mechanical (tensile, flexural, impact and hardness), water absorption and thermal (heat deflection temperature and thermo-gravimetric analysis) properties of the DSF-VE composites were experimentally evaluated. Scanning electron microscopic analysis was carried out to analyse the surface characteristics and fractured surface of the DSF-VE composites. It was evident from the results obtained that 30 wt% of the DSF-VE composites exhibited the highest mechanical properties: impact, tensile, hardness and flexural of 17.03 KJ/m2, 40.3 MPa, 51 and 149 MPa, respectively, among the fabricated composites. Similarly, the heat deflection temperatures of DSF-VE composites increased by 58.49%, when compared with the neat, pure vinyl ester resin. The thermo-gravimetric analysis showed that the natural filler-based (DSF-VE) composites possessed thermal stability up to 400.2 °C, which was within the polymerisation process temperature. Furthermore, the DSF-VE composites have been successfully utilized for various potential applications, such as fabrication of a table fan blade, an engine guard for two-wheelers and self-motor guard for four wheelers.