No abstract

No abstract

Bacterial cellulose (BC) has profound applications in different sectors of biotechnology due to its unique properties preferring it about plant cellulose.Although this polymer is extremely important in various applications, many problems still hinder the sustainable production in terms of increasing productivity and low-cost production. In order to overcome these problems, this study will focuses on the continuous production of cellulose using immobilized Glucanobacter xylinum cells onto Sugar Cane Bagasse (SCB) and Ca-alginate beads. Comparatively, adsorption of Glucanobacter xylinum cells to the cavum of stalk cells of SCB could be efficiently stable while, entrapment of cells onto Ca-alginate has drawback observed by the rapid disruption and instability of the beads in the Potato Peel Waste (PPW) culture medium. Our findings demonstrate that a combination between alternative low-cost medium with continuous production mode by immobilization onto inexpensive natural polymer can promote a sustainable bioprocess and reduction the production cost.

No abstract

Biopolymers have attracted much of interest in various applications needed for sustainable and biodegradable solutions. Indeed, biopolymers lessen the requirement for petroleum‐based resources, municipal solid waste output, and carbon dioxide emissions. Polysaccharides are a unique category of biopolymers that are especially characteristic such as biocompatibility and editability. Polysaccharides functionalization plays a significant role in various applications and their suitability for additive applications. Sensor‐based polysaccharides are widely used with many drawbacks localized in durability, moldability, and sensitivity. Otherwise, biosensors are devices monitoring a specimen's biological phenomena or measurements, usually not disposable devices. For that, biosensors are needed urgently to address the high cost of disposable supplies in the medical diagnostic industry, which span many elements of medical diagnostic applications. Additionally, manipulating of polysaccharide‐based materials is considered accessible and usable and requires low equipment requirements. Herein the main features of polysaccharides will be discussed, along with potential applications as biosensors for medical diagnosis and new lines of inquiry with such focus on the main required to formulate polysaccharides biosensors.This article is protected by copyright. All rights reserved

Paper coating plays an important role in the paper properties, printability and application. The nanocoating is a multifunction layer that provides the paper with unique features. In this work, nanocoating formulas were prepared using a green method and component. The nanocoating formulas were based on biopolymers nanostarch NSt and nanochitosan NCh (NCS) decorated with Egyptian kaolinite Ka doped with zinc nanoparticles NCS@xka/ZnONPs (x represents different ratios) support for multifunctional uses. The nanocoating formulas were characterized using a physiochemical analysis as well as a topographical study. FTIR, XRD, SEM and TEM techniques were used. Additionally, the antimicrobial activity of the tested samples was assessed against six microorganisms including Gram-negative and Gram-positive bacteria. The prepared nanocoating formulas affirmed excellent antimicrobial activity as a broad-spectrum antimicrobial active agent with excellent activity against all representative microbial communities. The nanocoating with the highest ratio of Ka/ZnONPs (NCS@40 ka/ZnONPs) showed excellent antimicrobial activity with an inhibition percentage of more than 70% versus all microorganisms presented. The paper was coated with the prepared suspensions and characterized concerning optical, mechanical and physical properties. When Ka/ZnONPs were loaded into NCS in a variety of ratios, the characteristics of coated paper were enhanced compared to blank paper. The sample NCS@40 ka/ZnONPs increased tensile strength by 11%, reduced light scattering by 12%, and improved brightness and whiteness by 1%. Paper coated with NCh suspension had 35.32% less roughness and 188.6% less porosity. When coated with the sample NCS@10 ka/ZnONPs, the coated paper's porosity was reduced by 94% and its roughness was reduced by 10.85%. The greatest reduction in water absorptivity was attained by coating with the same sample, with a reduction percentage of 132%.

The paper coating is an out-layer of the paper that plays an important role in a paper’s properties, functionality and application. The nanocoating is a multifunction layer that supplied the paper with unique features. In this present work, nanocoating formulas were prepared using a green method and component as well. The nanocoating formulas were based on biopolymers (nanostarch and nanochitosan) decorated with Egyptian kaolinite doped with zinc nanoparticles (Ka/ZnONPs) as support for multifunctional uses. The nanocoating formulas were characterized using a physiochemical analysis as well as a topographical study. Additionally, the prepared nanocoating formulas affirmed an excellent antimicrobial activity as a broad-spectrum antimicrobial active agent with excellent activity against all representative microbial communities. Besides, the coated paper's optical, mechanical and physical properties were improved.

Bacterial Cellulose (BC) is still the most renewable available biopolymer produced in fine nature from alternative microbial sources as bacteria. In the present study, newly BC producing bacteria were successfully isolated from acidic fruits. The most potent producer was isolated from strawberry and identified genetically using 16 s rRNA technique as Achromobacter S3. Different fruit peels were screened to produce BC using the cheapest culture medium. Among them, Mango peel waste (MPW) hydrolysate proved to be the significant inducible alternative medium without any extra nutrients for the maximum productivity. Improvement of the BC yield was successfully achieved via statistical optimization of the MPW culture medium, from 0.52 g/L to 1.22 g/L with 2.5-fold increased about the standard HS culture medium. Additionally, the physicochemical analysis affirmed the cellulose molecular structure as well as observed the crystallinity of nanofiber as 72 and 79% for BC produced by Achromobacter S33 on HS and MPW media, respectively. Moreover, the topographical study illustrated that the BC nanofibers had close characteristics upon fiber dimeter and length as about 10 and 200 nm, respectively.