Biotechnological innovations in nanocellulose production from waste biomass with a focus on pineapple waste.

New materials' synthesis and utilization have shown many critical challenges in healthcare and other industrial sectors as most of these materials are directly or indirectly developed from fossil fuel resources. Environmental regulations and sustainability concepts have promoted the use of natural compounds with unique structures and properties that can be biodegradable, biocompatible, and eco-friendly. In this context, nanocellulose (NC) utility in different sectors and industries is reported due to their unique properties including biocompatibility and antimicrobial characteristics. The bacterial nanocellulose (BNC)-based materials have been synthesized by bacterial cells and extracted from plant waste materials including pineapple plant waste biomass. These materials have been utilized in the form of nanofibers and nanocrystals. These materials are found to have excellent surface properties, low density, and good transparency, and are rich in hydroxyl groups for their modifications to other useful products. These materials are well utilized in different sectors including biomedical or health care centres, nanocomposite materials, supercapacitors, and polymer matrix production. This review explores different approaches for NC production from pineapple waste residues using biotechnological interventions, approaches for their modification, and wider applications in different sectors. Recent technological developments in NC production by enzymatic treatment are critically discussed. The utilization of pineapple waste-derived NC from a bioeconomic perspective is summarized in the paper. The chemical composition and properties of nanocellulose extracted from pineapple waste may have unique characteristics compared to other sources. Pineapple waste for nanocellulose production aligns with the principles of sustainability, waste reduction, and innovation, making it a promising and novel approach in the field of nanocellulose materials.

A review on the treatment of intimal hyperplasia with perivascular medical devices: role of mechanical factors and drug release kinetics.

INTRODUCTION: Intimal hyperplasia (IH) is a significant factor limiting the success of revascularization surgery for blood flow restoration. IH results from a foreign body response and mechanical disparity that involves complex biochemical reactions resulting in graft failure. The available treatment option utilizes either different pharmacological interventions or mechanical support to the vascular grafts with limited success. AREAS COVERED: This review explains the pathophysiology of IH, responsible mechanical and biological factors, and treatment options, emphasizing perivascular devices. They are designed to provide mechanical support and pharmacology actions. The perivascular drug delivery concept has successfully demonstrated efficacy in various animal studies. Accurate projections of drug release mechanisms using mathematical modeling could be used to formulate prolonged drug elution devices. Numerical modeling aspects for the prediction of design outcomes have been given due importance that fulfills the unmet clinical need for better patient care. EXPERT OPINION: IH could be effectively prevented by simultaneous mechanical scaffolding and sustained local drug delivery. Future perivascular medical devices could be designed to integrate these essential features. Numerical modeling for device performance prediction should be utilized in the development of next-generation perivascular devices.

Perivascular patch using biodegradable polymers: Investigation of mechanical and drug elution characteristics.

Intimal hyperplasia (IH) is the primary cause for the vascular graft stenosis. Perivascular devices offer a potential treatment option to reduce the impact of intimal hyperplasia by providing mechanical support and local administration of therapeutic agents to control cellular overgrowth. In the present study, a perivascular patch primarily made up of biodegradable polymer, Poly L-Lactide, has been designed with adequate mechanical strength and ability for sustained drug elution of anti-proliferative drug (Paclitaxel). The elastic modulus of the polymeric film has been optimized by blending the base polymer with different grades of biocompatible polyethylene glycols. Using design of experiments, the optimized parameters were obtained as PLLA with 2.5% PEG-6000 and have shown 3.14 MPa elastic modulus. The film prepared based on optimum conditions has been employed for prolonged drug delivery (about four months) under simulated physiological conditions. The addition of drug release rate enhancer (polyvinyl pyrrolidone K90F) has improved the drug elution rate and ∼83% drug was released over entire study period. The molecular weight of the base biodegradable polymer was estimated by gel permeation chromatography (GPC) which remained unchanged during the drug release study duration. Evidences of Paclitaxel drug crystallization were found to contribute to the sustained drug elution. The SEM examination of the surface morphology post-incubation revealed micropores on the surface, contributing to the overall drug release rate. The study concluded that perivascular biodegradable films could be tailored for their mechanical properties, and sustained drug elution could also be formulated with reasonable choices of biodegradable polymer and biocompatible additives.

Advances and trends in encapsulation of essential oils.

There is a huge concern regarding the potential carcinogenic and mutagenic risks associated with the usage of synthetic chemicals as preservatives in various consumer products such as food and pharmaceutical formulations. In this aspect, there is a need for the development of alternative natural preservatives to replace these synthetic chemicals. More recently, naturally occurring essential oils have emerged as popular ingredients owing to their unique characteristics like antioxidant and antimicrobial activity, to enrich and enhance the functional properties of consumer products. However, due to their high volatility and hydrophobicity, their functionality is lost and their incorporation in aqueous products is challenging. One of the promising strategies to overcome this challenge is encapsulation which involves the entrapment of the essential oil inside a biocompatible material for its controlled release and increased bioavailability. Also, the choice of encapsulation method depends on the component to be encapsulated and the shell material. In this review, encapsulation in various colloidal systems that facilitate the potential delivery of essential oils is discussed. The focus is on encapsulation techniques along with their advantages and disadvantages, encapsulation efficiency, and in vitro release studies.

Pineapple peel waste valorization for extraction of bio-active compounds and protein: Microwave assisted method and Box Behnken design optimization.

Pineapple peel waste (PPW) is obtained in huge quantities out of pineapple canning industries and it is found to be rich in bioactive compounds with antioxidant activity and an opulent source of bromelain protein having commercial importance. To fulfil the purpose, microwave assisted extraction was considered. Three parameters varied were solvent to substrate ratio, microwave power and extraction time. The independent variables were solvent to substrate ratio (10:1 mL/g to 20:1 mL/g), microwave power (300 W-600 W) and extraction time (40 min-50 min). Optimization was done with three factors and three level Box- Behnken Design (BBD). Each of the experiment has been analysed for Total phenolic content (TPC), Total flavonoid content (TFC), Total tannin content (TTC) as well as for protein content. The Folin- Ciocalteu method was utilized for analysing TPC, TTC and the colorimetric method (AlCl3) was used for the analysis of TFC, protein content was analysed by lowry's method and antioxidant activity making use of 2,2-diphenyl-1-picrylhydrazyl (DPPH). The p values were less than 0.05 which showed all the four models were significant. The experimental values and the predicted values were harmonious for the optimum conditions. The optimum condition obtained out of BBD were solvent to substrate ratio of 20:1 mL/g, microwave power of 600 W and extraction time 40 min. Antioxidant activity for the extract was found out by DPPH assay under the optimized conditions was 75% along with proteolytic activity of bromelain as 1647.612 GDUgconcentrate-1.

Unraveling the solubilization and cytotoxicity study of poorly water-soluble anti-inflammatory drug in aqueous Gemini surfactants solution with physicochemical characterization and simulation study.

This work investigates the use of quaternary ammonium based Gemini surfactants (GS) to examine the solubilization and stabilization of a poorly water soluble anti-inflammatory drug Diclofenac (Df). Here we demonstrate the effect of pH on the suspension profile of Df release where it exhibits maximum solubility and absorbance at pH = 10. Interaction process of such cationic GS with Df have been systematically characterized using tensiometry and UV-vis spectroscopy techniques from pre-micellar to post-micellar regions. The spectral results revealed that all the individual GS bind on Df electrostatically resulting in GS + Df complexation. For all the three GS examined, the critical micelle concentration (CMC) was found to decrease in presence of Df following the order: 12-2-12 > 12-2-16 > 16-2-16 which inferred that 12-2-12 can effectively suppress Df degradation at very low concentration. In comparison to 12-2-12, 12-2-16 and 16-2-16 exhibited weaker interaction with Df which limits the stability/solubility of Df in their respective micelles. The aggregation behavior of Df with various GS was investigated by dynamic light scattering (DLS) method. The structural orientation of GS and Df was elucidated by molecular simulation study using Gauss View 5.0.9. The influence of the 12-2-12 in presence of Df on the cervical cell morphology has been undertaken to understand the cytotoxic effect using MTT assay.

Sono hydrodistillation for isolation of citronella oil: A symbiotic effect of sonication and hydrodistillation towards energy efficiency and environment friendliness.

Environmental benign approach for extraction of essential oil was made. An essential oil rich in citronellol, linalool and citronellal was extracted from the leaves of Cymbopogon winterianus using a clean hybrid extraction technique, sono hydrodistillation. Sono hydrodistillation combines ultrasonic waves along with conventional hydrodistillation process to have symbiotic outcomes in terms of process improvement. Significant process parameters such as size of the plant material, extraction time, power, ultrasound amplitude, pulse interval and solid loading were investigated independently to study the effect on yield of oil and composition of oil. The water residue remained after extraction of volatile oil was analyzed using Folin-Ciocalteu method to determine the total phenolic content (TPC) which would help in assessing the residue as a useful by-product. Substantial reduction in time was observed with the inclusion of ultrasound compared to conventional hydrodistillation. Further, to optimize the extraction conditions, observe interactive effects of various parameters and develop mathematical model, response surface methodology was employed. The maximum yield of oil was found to be 4.118% (w/w) at 21 min extraction time, 5 g solid loading, 250 mL water volume, 500 W heating mantle power, 70% ultrasonic amplitude and 10:50 pulse interval. Total phenolic content was 13.84 mg GAE/g DM. The citronella oil was found to be composed of 27.47% of linalool, 11.52% of citronellal, 34.25% citronellol and 11.15% of elemol. Extraction time, solid loading and pulse interval had the significant influence on the yield of oil and total phenolic contents. Microscopic analysis has assisted in envisaging the probable mechanism indicating the role of sonication for rapid extraction. This novel technique was compared with the conventional hydrodistillation to ascertain the impact towards process intensification. Sono hydrodistillation was found to be a greener and cleaner process as energy consumption has been reduced by 40% while carbon footprint has shrunken by 47%.

Synergism and aggregation behaviour in an aqueous binary mixture of cationic-zwitterionic surfactants: physico-chemical characterization with molecular simulation approach.

Aqueous interactions between a cationic surfactant benzyl dimethylhexadecylammonium chloride (BDHAC) and alkyldimethylammoniopropane sulfonates (CnDAPS) based three zwitterionic surfactants n = 10, 12, and 14 (abbreviated as C10DAPS, C12DAPS and C14DAPS, respectively) were studied using tensiometry, and fluorescence spectrophotometry techniques. The critical micelle concentration degree of synergism and various other parameters such as interaction parameter (ß), activity coefficients (fm) and interfacial parameters such as surface pressure (πCMC), packing parameter (P), surface excess concentration (Γmax), surface tension at CMC (γCMC), and minimum area per molecule (Amin) were evaluated using the Regular Solution Theory (RST) of mixed systems. The results indicate a strong dependency on the mixed system and their composition. For the quantitative prediction, the molecular architecture of the surfactants in mixed systems and their synergistic interactions were investigated by computational simulation using Spartan'14 V1.1.8. The structural optimization results obtained were found to be in good agreement with the estimations made using RST. The reduction in surface tension indicates a certain efficiency in mixed micelle formation owing to electrostatic attraction between the cationic and zwitterionic surfactants. In addition, the binary surfactant systems evaluated by Maeda's approach infer the mixed micelles are thermodynamically stable. The aggregation number (Nagg) appeared to be larger at the composition point where the efficiency of mixed micelle formation is greatest. The strength of the interaction between BDHAC and CnDAPS followed the order: C14DAPS > C12DAPS > C10DAPS indicating a greater synergism at 0.25 molar ratio of zwitterionic surfactants to cationic surfactants in the aqueous solution at 303.15 K.

Highly efficient micellar extraction of toxic picric acid into novel ionic liquid: Effect of parameters, solubilization isotherm, evaluation of thermodynamics and design parameters.

A simple and new approach in cloud point extraction (CPE) method was developed for removal of picric acid (PA) by the addition of N,N,N,N',N',N'-hexaethyl-ethane-1,2-diammonium dibromide ionic liquid (IL) in non-ionic surfactant Triton X-114 (TX-114). A significant increase in extraction efficiency was found upon the addition of dicationic ionic liquid (DIL) at both nearly neutral and high acidic pH. The effects of different operating parameters such as pH, temperature, time, concentration of surfactant, PA and DIL on extraction of PA were investigated and optimum conditions were established. The extraction mechanism was also proposed. A developed Langmuir isotherm was used to compute the feed surfactant concentration required for the removal of PA up to an extraction efficiency of 90%. The effects of temperature and concentration of surfactant on various thermodynamic parameters were examined. It was found that the values of ΔG° increased with temperature and decreased with surfactant concentration. The values of ΔH° and ΔS° increased with surfactant concentration. The developed approach for DIL mediated CPE has proved to be an efficient and green route for extraction of PA from water sample.