Biology subjects

Althuri, A.

Publications and source records attributed to Althuri, A..

4 recordsLinked to original sources

bioRxiv2026

One-pot lactic acid production from rice straw: A consolidated bioprocess with enzymatic pretreatment-saccharification and Microbial co-fermentation

Global demand for platform chemicals and biomaterials urges us to seek sustainable strategies along with waste valorization to produce lactic acid (LA) sustainably. The study has designed a one-pot fermentation strategy by employing in-house produced ligninolytic and saccharifying enzymes on rice straw along with a consortium of hexose and pentose sugar co-fermenting microorganisms. Biological pretreatment with in-house ligninolytic enzyme was selected for the one-pot strategy from a comparison study of chemical and enzymatic pretreatment of rice straw. In this study, simultaneous pretreatment and saccharification of rice straw followed by LA fermentation by Lactobacillus casei- Lactobacillus rhamnosus system (35.58{+/-}0.29 g/L) was found out to be more efficient than Lactobacillus casei-Lactobacillus pentosus system (29.80{+/-}0.92 g/L). Thus, the L. casei- L. rhamnosus system (CR system) was selected and was further statistically optimized by response surface methodology (RSM) to yield 64.96 g/L of LA. The fermentation broth was decolorized and purified by ion exchange chromatography to yield 85.56% pure LA with 84.95% optical purity. The one-pot fermentation strategy has reduced the number of unit operations involved to synthesize LA from rice straw without compromising the yield and purity through a greener route. The use of in-house enzymes and consortium of lactic acid producing bacteria in one-pot presents a strategic approach to sustainable LA production. The biological enroute and the minimum use of chemicals during upstream, fermentation, and downstream processing adds to the carbon credit of the process. HighlightsO_LILactic acid was produced from rice straw using one-pot co-fermentation strategy C_LIO_LIUpstream processing employed in-house enzymes from fungal solid-state fermentation C_LIO_LIThe process addresses the underutilization of pentose sugars after saccharification C_LIO_LIA consortium LAB produced 64.96 g/L LA with 0.855 g/L.h productivity C_LIO_LIDownstream processing yielded LA with 85.56% purity and 84.95% optical purity C_LI

bioengineering↗

bioRxiv2025

Strong STMP-Crosslinked Lignin/Chitosan Hydrogel Films with Enhanced Aqueous Stability and Bioactivity for Active Food Packaging

Plastic pollution has intensified globally due to the widespread use of non-biodegradable packaging materials. Conventional passive plastics used in food packaging lack adaptive functionality limiting their preservation efficiency. Biopolymer-based hydrogels offer promise due to their biodegradability, film-forming ability, and intrinsic bioactivity. However, their instability in aqueous environments constrains their application in high-moisture foods such as meat. Lignin extracted from sugarcane tops via acid-alkali treatment and chitosan known for its film-forming and antimicrobial properties were combined to enhance the antioxidant, antimicrobial, UV-blocking, and mechanical performance of the hydrogel. The films were cured at 25 {degrees}C under 80% relative humidity, eliminating the high temperature pre-oven drying required in conventional methods. Further, a stable lignin/chitosan hydrogel film was developed using sodium trimetaphosphate (STMP) as a crosslinker and glycerol as a plasticizer. The films treated with 1% (w/v) STMP for 15 min showed optimal performance, exhibiting 89.89% radical scavenging activity, complete UV shielding, antimicrobial activity against E. coli, and tensile strength of 2364.79 MPa with 31.49% elongation at break. The film retained its integrity in food simulants namely ethanol (10% v/v), acetic acid (3% v/v), and distilled water. In chicken breast packaging trials, the CL-0.8/3Cht film-maintained pH, moisture, and protein stability and significantly reduced microbial load during 5 days of storage. These findings establish the CL-0.8Lig/3Cht hydrogel film with agri-residue derived lignin as a robust, multifunctional, and biodegradable active packaging material for moisture-rich food systems. These findings support waste valorisation advancing cleaner and sustainable food preservation practices.

bioengineering↗

bioRxiv2025

Green Synthesis of a Novel Gelatin Crosslinked Oxidized Pullulan-Lignin biocomposite film for active food packaging

Biopolymer-based plastics, made from plants and microbes, are gaining popularity in food packaging due to their eco-friendliness, but degrade upon contact with water, thus requiring the addition of water-resistant materials. Lignin was extracted from cotton stalk using the acid-alkali method and was characterized through FTIR and 2D HSQC NMR to evaluate its structure and purity. Pullulan dialdehyde, gelatin, and lignin were blended using a green process to make water-stable PGL hydrogel film. Incorporation of Lignin into PDA/Gelatin blend, having imine bonds, increased network strength and solvent-resistance by extensive physical interactions like H-bonding and electrostatic interactions, which were confirmed through FTIR and XPS analysis. These films were cured at 60{degrees}C, making the process energy efficient. PGL film exhibited water stability, high mechanical strength, moisture barrier, and bioactive properties ideal for fruit preservation. Lignin improved hydrophobicity, hydrogel strength, biodegradability, and non-flammability relative to the control. The films effectiveness for food packaging was assessed by analyzing the impact on the preservation and shelf life of kinnow oranges. Physical properties, such as weight loss, firmness, and chemical properties, including pH, titratable acidity, lipid oxidation, sucrose content, antioxidant activity, and ethylene concentration of oranges before and after packaging, were monitored. PGL film showed high stability in hot and ambient water, with a water swelling index of 303%, impressive tensile strength of 8.5 MPa, and elongation at break exceeding 72%. PGL-packed oranges produced 0.034{+/-}0.0032 ppm/g of ethylene after seven days, which is 4.2-fold lower than unpacked oranges, signifying the fruit preservation ability of PGL films.

bioengineering↗

bioRxiv2024

Tuning of Chitosan with Lignin derived Bioactive Properties to develop a Lignin Reinforced and Sustainable Food Packaging Biomaterial

The crucial component of food storage, preservation, and transportation is food packaging. Biodegradable biopolymers are a major area of focus for the future development of food packaging materials due to their ability to mitigate adverse environmental impact by reducing plastic pollution and promoting sustainable waste management practices. Exploring renewable resources is crucial for facilitating the transition from non-renewable practices to sustainability. Chitosan is known for its superior film-forming abilities but has limited antibacterial activity. The inherent properties of lignin, including its high tensile strength, antioxidant, antimicrobial, and UV barrier ability, can contribute to enhance chitosan film performance when added as a co-polymer, making it an active material for food packaging applications. The present work explores the acid-alkali treatment to extract lignin from sugarcane tops, an abundant agricultural waste, and the application of extracted lignin in biopolymer-based hydrogel synthesis for food packaging. The goal is to enhance the hydrogel formulation by incorporation and optimisation of lignin that holds high antioxidant, antimicrobial, UV barrier, and mechanical properties along with significantly low water transmissibility. This study introduces a novel approach by utilizing lignin extracted from sugarcane tops (SCT) rather than commercially derived lignin, thereby expanding the raw material scope of lignin applications. The incorporation of higher proportions of lignin in the hydrogel formulations represents an advancement over reported studies, aimed at improving the bioactivity of the hydrogel by leveraging its advantageous characteristics emanating from lignin. This approach can also reduce the dependency on chitosan which is relatively expensive. Further, the modified synthesis of hydrogels expedited through heating method contributes to shorten the time duration needed for hydrogel film casting and drying. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=139 SRC="FIGDIR/small/592363v1_ufig1.gif" ALT="Figure 1"> View larger version (48K): org.highwire.dtl.DTLVardef@c88b2forg.highwire.dtl.DTLVardef@29c658org.highwire.dtl.DTLVardef@9ce06borg.highwire.dtl.DTLVardef@151a8b5_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIEnhanced lignin extraction from sugarcane tops using Plackett Burman Design C_LIO_LIFormulating green packaging hydrogels through valorisation of sugarcane tops C_LIO_LIHeating-based short time casting method for Lignin/Chitosan hydrogel synthesis C_LIO_LIOptimization of lignin content in the hydrogels for balanced mechanical and bioactive properties C_LI

bioengineering↗