The aim of this study was to investigate the effect of hydrotrope as a pretreatment process on rice straw for bioethanol production. Sodium cumene sulfonate and sodium xylene sulfonate (Na–X) were ...used as hydrotropes to delignify rice straw. Effects of biomass loading, time, temperature and hydrotrope concentration were studied for both the hydrotropes. There was no loss of cellulose & hemicellulose in the hydrotrope solution. Sodium cumene sulfonate could remove more than 50% of lignin from rice straw with 5% biomass loading at 121 °C for 1 h. Reusability of aqueous hydrotrope solution was demonstrated. Enzymatic digestibility of the hydrotrope pretreated rice straw was studied and evaluated for subsequent bioethanol production. The use of the hydrotrope for biomass pretreatment has the potential to mitigate the environmental impact of chemical pretreatment.
•Hydrotropic pretreatment was carried out on rice straw using alkyl benzene sulfonates.•Glucose yield significantly improved after hydrotropic pretreatment.•Hydrotrope solution of sodium cumene sulfonate can be efficiently reused for five cycles.•First report on hydrotropic pretreatment on rice straw for bioethanol production.
The production of cellulosic ethanol from biomass is considered as a promising alternative to fossil fuels, providing a sustainable option for fuels production in an environmentally compatible ...manner. The presence of lignin poses a significant challenge for obtaining biofuels and bioproducts from biomass. Part of that problem involves understanding fundamental aspects of lignin structure which can provide a pathway for the development of improved technologies for biomass conversion. Hydrotropic pretreatment has several attractive features that make it an attractive alternative for biofuel production. This review highlights the recent developments on hydrotropic pretreatment processes for lignocellulosic biomass on a molecular structure basis for recalcitrance, with emphasis on lignin concerning chemical structure, transformation and recalcitrance. The review also evaluates the hydrotropic delignification in comparison to alkaline delignification on lignin reduction and surface coverage by lignin. The effect of hydrotrope pretreatment on enzymatic saccharification has also been discussed.
Lignin nanoparticles (LNP), extracted from spent materials of Dashamoola Arishta (Ayurvedic formulation), shared a molecular weight of 14.42 kDa with commercial lignin. Processed into LNPs ...(496.43 ± 0.54 nm) via planetary ball milling, they demonstrated stability at pH 8.0 with a zeta potential of −32 ± 0.27 mV. Operating as Pickering particles, LNP encapsulated curcumin and vitamin D3 in sunflower oil, forming LnE + Cu + vD3 nanoemulsions (particle size: 347.40 ± 0.71 nm, zeta potential: −42.27 ± 0.72 mV) with high encapsulation efficiencies (curcumin: 87.95 ± 0.21%, vitamin D3: 72.66 ± 0.11%). The LnE + Cu + vD3 emulsion exhibited stability without phase separation over 90 days at room (27 ± 2 °C) and refrigeration (4 ± 1 °C) temperatures. Remarkably, LnE + Cu + vD3 exhibited reduced toxicity, causing 29.32% and 34.99% cell death in L6 and RAW264.7 cells respectively, at the highest concentration (50 μg/mL). This underscores the potential valorization of Ayurvedic industry spent materials for diverse industrial applications.
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•Lignin nanoparticles (LNP) were produced from Ayurvedic spent materials•LNPs were maximally stable, had lowest particle size and highest zeta potential at pH 8.0•LNP produced stable Pickering emulsions and encapsulated curcumin and vitamin D3•These Pickering emulsions were stable for 90-day at refrigerated temperature•There was no observable phase separation even at room temperature for 90 days
Acid and alkali pretreatment are the most commonly employed strategy in a lignocellulosic biorefinery. The main objective of the study was to evaluate the chemical implications of acid and alkali on ...the lignin structure and subsequently on the adhesive performance. The study also aimed to investigate the effect of complete replacement of phenol and formaldehyde in the commercial wood adhesive with phenolic lignin and glyoxal, respectively. The phenolic lignin was derived from the two differentially pretreated sugarcane bagasse, i.e., acid and alkali. The isolated lignin was characterized and utilized for the synthesis of lignin-based glyoxal resin. The resins were comparatively evaluated for their mechanical properties as wood adhesives. Adhesives derived from acid pretreated sugarcane bagasse were found to be superior to lignin derived from alkali pretreated sugarcane bagasse in terms of mechanical properties and shear strength.
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Acid pretreatment is the most common method employed in the lignocellulosic biorefinery leading to the separation of pentose and hexose sugar. The liquor obtained after pretreatment (acid ...pretreatment liquor or APL) needs to be detoxified prior to fermentation. The aim of this study was to design functional groups on a polymer matrix which are selective in their interaction to inhibitors with little or no specificity to sugars. Molecular modeling was used as a tool to design a suitable adsorbent for selective adsorption of inhibitors from a complex mixture of APL. Phenyl glycine-
p
-sulfonic acid loaded on chloromethylated polystyrene polymer was designed as an adsorbent for selective interaction with inhibitors. Experimental verification of the selectivity was successfully achieved. The current study provides insights on the adsorptive separation processes at the molecular level by design of specific adsorbent which can be tailor made for the better selectivity of the desired component.
The extraction of forskolin from Coleus forskohlii roots using organic solvents was facilitated by irradiation of the raw material by microwave and studied for effect of time of irradiation, power ...level and water soaking of the raw material prior to irradiation on the rate of extraction. Methanol gave 92% extraction of forskolin after 2 min of the irradiation at 160 W under optimized conditions, with simultaneous increase in the rate of extraction. Molecular modeling approach was taken to design a specific adsorbent for selective adsorption of forskolin analogues from the complex extract. The forskolin analogues showed greater affinity toward a diethanolamine-loaded polymer as compared to forskolin. The purification of forskolin by adsorption on diethanolamine substituted polystyrene validated the predictions from molecular simulation.
•Isolation of lignin from the enzymatic residue of acid pretreated sugarcane bagasse yielded high recovery and purity using alkaline and organosolv process.•Organosolv lignin and Alkali lignin with ...higher guaiacyl units and free ortho(C5) positions have great potential to replace the phenol in phenol-formaldehyde resin•Oxidation of lignin using Laccase improved its reactivity for the synthesis of 100% lignin-based resin.•First report on the comparative evaluation of Laccase mediated oxidized and unoxidized lignin for the synthesis of lignin-based formaldehyde resin.
Pretreatment using dilute acid is one of the strategies employed in a lignocellulosic biorefinery. The current study deals with the isolation, characterization, and oxidation of lignin from the enzymatic residue of acid pre-treated sugarcane bagasse. The study also focused on evaluating the reactivity of Laccase mediated oxidized lignin with the non-oxidized one for the preparation of lignin-based formaldehyde (LF) resin. In the current study, 100 % phenolic lignin was utilized for the synthesis of LF resin. Three different approaches (Alkaline hydrolysis, mild acidolysis & organosolv) have been employed to evaluate the effect of isolation method on the physicochemical properties of lignin. The isolation method had a bearing on the properties of lignin and its reactivity towards formaldehyde for the synthesis of LF resin. Alkali and organosolv lignin were found as promising candidates for the preparation of LF resin. Oxidized lignin exhibited better reactivity than the non-oxidized one.
The adsorption of forskolin and its analogues has been studied, a priori, by molecular modeling to design a suitable adsorbent for selective adsorption of forskolin from a complex extract. Ligands ...selective for forskolin have been designed on the basis of two-point attachments with forskolin so as to have desired selectivity. Dynamic adsorption and desorption experiments were conducted to establish the optimum parameters for the purification process using a functionalized polymer. After a single adsorption and desorption cycle, the purity of the forskolin increased to 98% using phenyl glycine-p-sulfonic acid substituted polystyrene as a functionalized polymer. Experimental verification of the selectivity of the ligand toward forskolin was successfully achieved.
The objective of this study was to evaluate the effect of hydrotropic delignification of cotton stalk on sugar release performance for bioethanol production. In this study, different alkyl benzene ...sulfonates were screened to select the best pretreatment agent, and the effectiveness of pretreatment was evaluated by enzymatic saccharification. Sodium cumene sulfonate was found to be the best hydrotropic agent in terms of reducing sugar yield. Parameters such as hydrotrope concentration, biomass loading and incubation time were optimized by adopting a central composite design. Under optimized pretreatment conditions, 0.211 g reducing sugar/g of dry biomass was obtained. Reusability of aqueous hydrotrope solution was also demonstrated.
Hydrotropic delignification using alkyl benzene sulfonates was studied on cotton stalk.
Total reducing sugar was fairly enhanced after hydrotropic pretreatment using sodium cumene sulfonate.
Hydrotrope solution of sodium cumene sulfonate can be efficiently reused for five cycles.
This is the first report on hydrotropic delignification of cotton stalk by statistical optimization for the efficient release of reducing sugars by enzymatic hydrolysis.
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/locate/withdrawalpolicy).
This article has been retracted at the request of Elsevier's ...Research Integrity & Publishing Ethics team and an independent ethics advisor.
A journal-wide investigation identified violations of the journal's policies on authorship and conflict of interest related to the submission and review of this paper.
Review of the initial submission of this paper was handled by the then journal Editor-in-Chief (Ashok Pandey) and revision required. Upon submission of the revised version, the journal Editor-in-Chief was added as a co-author and the Editor-in-Chief continued to handle the review process, eventually accepting the paper for publication. This compromised the editorial process and breached the journal's policies.
This investigation was carried out by Elsevier's Research Integrity & Publishing Ethics team, independent of the journal editorial board. The findings and recommendations have been confirmed by an independent ethics advisor.
The authors disagree with the retraction and dispute the grounds for it.
