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1.
J Food Sci ; 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39042498

ABSTRACT

The present work investigates the in vitro cholesterol reduction bioactivity of epigallocatechin gallate (EGCG) prior to and after nano-encapsulation using potato starch nanoparticle (SNP) as wall material. EGCG encapsulation in potato SNPs was achieved through a green inclusion complexation method. The encapsulated EGCG was characterized for its morphology, thermal, and crystalline properties using FESEM, DSC, XRD, and Fourier transform infrared (FTIR) studies. The bioactivity of EGCG to reduce gut cholesterol was studied using in vitro micellar cholesterol solubility study. The encapsulated EGCG exhibited enhanced thermal and crystalline properties. The FESEM results indicated successful nano-encapsulation of EGCG at 20-120 nm diameter. The melting point enhanced from 225.7°C in EGCG to 282.9°C in encapsulated EGCG. The crystallinity also enhanced and could be observed through the increased intensity in the encapsulated EGCG. The FTIR results affirmed a shifting of peaks at 3675, 2927, 1730, and 1646 cm-1, which corresponds to formation of new H bonds and confirms successful encapsulation of EGCG in SNPs. Further, EGCG had significantly reduced the cholesterol concentration by 91.63% as observed through the in vitro micellar inhibition study. The encapsulated EGCG was not able to reduce cholesterol as observed in the in vitro micellar cholesterol solubility study. This effect occurred due to the unavailability of EGCG after it formed a complex with SNPs. PRACTICAL APPLICATION: This study first investigates the utilization of newly synthesized potato starch nanoparticles as a coating material for nano-encapsulation of EGCG. The enhanced thermal and crystalline properties of these nanoparticles contribute to improved attributes in the nano-encapsulated EGCG. Such properties hold promise for applications in functional food matrices subjected to high-temperature processing, including functional cookies, bread, and cakes. Furthermore, this research explores the bioactivity of EGCG concerning its capacity to reduce gut cholesterol levels. It also examines the potential application of nano-encapsulated EGCG in lowering gut cholesterol through a micellar solubility study.

2.
Article in English | MEDLINE | ID: mdl-38858287

ABSTRACT

Growing concern about global warming and greenhouse effects has led to persistent demands for increased energy efficiency and reduced carbon dioxide emissions. As a result, energy-intensive processing of carbon dioxide separation became imperative. Accordingly, energy-efficient, economically viable carbon dioxide separation technologies are sought as carbon dioxide capture options for future industrial process schemes. The article provides an overview of current technology for the separation of carbon dioxide, specifically focusing on adsorption. In this study, amine-loaded Zeolite-Y adsorbents were evaluated to enhance carbon dioxide adsorption capacity through synthesis, characterization, and the adsorption of carbon dioxide, within the context of current trends in separation technology. This study aims to study the ability of amine-loaded Zeolite-Y to adsorb carbon dioxide using three different loadings ethanolamine, diethanolamine, and triethanolamine. The amine-loaded materials were characterized by various technologies, including X-ray diffraction pattern (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), and field emission scanning electron microscope (FESEM) studies. The study suggests that monoethanolamine-loaded Zeolite-Y is a promising and cost-effective adsorbent for carbon dioxide adsorption in comparison to other synthesized amine-loaded adsorbents. The adsorbent has been able to adsorb carbon dioxide in the range of 1.14-2.26 mmol g-1 at 303 K and 1 bar for a loading of 1, 5, and 10 wt.% amine groups.

3.
Chemosphere ; 354: 141653, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38485000

ABSTRACT

Contemporary advances in material development associated with membrane gas separation refer to the cost-effective fabrication of high-performance, defect-free mixed matrix membranes (MMMs). For clean energy production, natural gas purification, and CO2 capture from flue gas systems, constituting a functional integration of polymer matrix and inorganic filler materials find huge applications. The broad domain of research and development of MMMs focused on the selection of appropriate materials, inexpensive membrane fabrication, and comparative study with other gas separation membranes for real-world applications. This study addressed a comprehensive review of the advanced MMMs wrapping various facets of membrane material selection; polymer and filler particle morphology and compatibility between the phases and the relevance of several fillers in the assembly of MMMs are analyzed. Further, the research on binary MMMs, their problems, and solutions to overcome these challenges have also been discussed. Finally, the future directions and scope of work on quaternary MMM are scrutinized in the article.


Subject(s)
Carbon Dioxide , Excipients , Membranes , Natural Gas , Polymers
4.
Chemosphere ; 340: 139780, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37572711

ABSTRACT

The global issue of environmental contamination from industrial wastewater comprising Cu, Fe and Pb demands effective treatment strategies. In this article, a functional composite sorbent was devised to selectively remove copper, iron, and lead from a real-world mimicking wastewater system. For the purpose, high, medium, and low molecular weight chitosan with amine and hydroxyl functional groups were used as a substrate, and glutaraldehyde was used to anchor the organic compound with carboxymethyl groups. Characterization with X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray analyzer accompanied by field emission scanning electron microscope, and Brunauer-Emmett-Teller were conducted for the synthesized adsorbent. Accordingly, the properties of the adsorbent were evaluated to infer that the synthesis assured a purified and functionalized system. The surface area of the medium carboxymethyl chitosan derivative was analyzed as 31.43 m2 g-1. Various adsorption parameters were examined methodically to assess upon optimal removal requirements. The effect of adsorbent dosage, contact time and concentration on the adsorption of the studied metal ions were conducted and the optimum values were achieved at pH 3.82, 540 min contact duration and 1.2 g L-1 sorbent dose. Maximum adsorbent capacities of 344.83 mg g-1, 9.59 mg g-1, and 90.09 mg g-1 were realized for Cu, Pb, and Fe, respectively. The experimental measurements of the studied heavy metal ions inferred the best fitness of Langmuir isotherm equilibrium and pseudo second order kinetic models. Further, elution studies with easy-to-deploy low-cost acidic and basic eluents (HCl, HNO3, H2SO4, KOH, and NaOH) were conducted with cyclic adsorption-desorption strategies. These investigations confirmed the adsorbent's good reusability up to 3 cycles of adsorption and its proximity to serve as a potential material for multi-heavy metal ions elimination from complex adsorbate systems.


Subject(s)
Chitosan , Metals, Heavy , Water Pollutants, Chemical , Copper , Chitosan/chemistry , Lead , Wastewater , Adsorption , Metals, Heavy/chemistry , Ions , Water Pollutants, Chemical/chemistry , Kinetics , Hydrogen-Ion Concentration
5.
Int J Biol Macromol ; 242(Pt 1): 124812, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37178895

ABSTRACT

The simultaneous removal of Cu, Pb and Fe from water bodies has been targeted in this work with polyvinyl alcohol (PVA) and chitosan (low, medium, and high molecular weight) derivative and with cyclic desorption efficacy target. For a varied range of adsorbent loading (0.2-2 g L-1), initial concentration (187.7-563.1 mg L-1 for Cu, 5.2-15.6 mg L-1 for Pb, and 61.85-185.55 mg L-1 for Fe), and resin contact time (5 to 720 min), batch adsorption-desorption studies were conducted. After first adsorption-desorption cycle, the optimum absorption capacity was 6.85 mg g-1 for Pb, 243.90 mg g-1 for Cu, and 87.72 mg g-1 for Fe for the high molecular weight chitosan grafted polyvinyl alcohol resin (HCSPVA). The alternate kinetic and equilibrium models were analyzed along with the interaction mechanism between metal ions and functional groups. The cyclic desorption studies were carried out with simple eluent systems such as HCl, HNO3, H2SO4, KOH, and NaOH. The experiments revealed that the HCSPVA derivative has been an impressive, reusable, and effective sorbent for the mitigation of Pb, Fe, and Cu in complex wastewater systems. This is due to its easy synthesis, excellent adsorption capacity, quick sorption rate, and remarkable regeneration capabilities.


Subject(s)
Chitosan , Metals, Heavy , Water Pollutants, Chemical , Polyvinyl Alcohol , Lead , Adsorption , Kinetics , Hydrogen-Ion Concentration
6.
J Food Sci ; 86(2): 443-453, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33486781

ABSTRACT

This work addresses the optimality of hot water bath based refractance window drying (RWD) characteristics of 1 mm Curcuma longa (turmeric) slices. Mylar film thickness (125 to 350 µm) and water bath temperature (65 to 95 °C) have been considered as independent variables to evaluate drying kinetics and nutritional characteristics of the process product combination. Equilibrium drying time, moisture diffusivity, fitness of thin layer models, moisture content, total phenolic content, total flavonoids content, curcumin content, and antioxidant activity have been considered to evaluate the optimality of the RWD process parameters. It has been analyzed that while both parameters critically influence equilibrium drying time, only temperature had profound influence on nutritional characteristics. PRACTICAL APPLICATION: There is a need for a fast-drying method without significant loss in bioactive compounds. Refractance window drying (RWD) method is such a process. The study of RWD of turmeric slices will help in understanding the relations between different drying temperatures and mylar film thickness and its relation to nutritional characteristics of the product.


Subject(s)
Curcuma/chemistry , Desiccation/methods , Flavonoids/chemistry , Antioxidants , Food Handling , Heating , Phenols/analysis , Plant Extracts/chemistry , Temperature , Water
7.
J Food Sci Technol ; 57(12): 4599-4612, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33087972

ABSTRACT

Musa balbisiana Colla blossom has enriched applications as a key constituent of dried vegetable formulations. With restricted prior art, the article addresses the optimality of tray drying characteristics of the blossom from both statistical design and drying kinetics perspective. The process variables in due course of optimization refer to moisture content, antioxidant activity and vitamin C for variation in drying time and temperature. Model fitness, analysis of variance based analysis and numerical optimization were considered during the statistical design of experiments. Drying kinetics involved fitness studies of alternate models, moisture diffusivity and process variable characteristics. Thereby, the sensitivity of both approaches to obtain optimal parameters associated with tray dried product have been targeted for a comparative assessment.

8.
Int J Biol Macromol ; 155: 260-272, 2020 Jul 15.
Article in English | MEDLINE | ID: mdl-32224173

ABSTRACT

This work addresses response surface methodology (RSM) design based investigations to obtain optimality of quaternary formulations [variant macromolecular concentrations of starch (St, 5-10 w/w%), polyvinyl alcohol (PVA, 5-10 w/w%), citric acid (CA, 15-40 wt%) and glycerol (Gl, 15-40 wt%)] associated to wound dressing films. Appropriate combinations of the swelling index (SI), weight loss (WL%) during 27 days, tensile strength (TS) and percentage elongation (%E) have been considered during such studies. The optimized composition was achieved through RSM optimization and exhibited very good water absorption (300.5% SI) and flexibility (87.5%E), and acceptable in-vitro degradation (51.4% WL) and TS (5 MPa) values, which are significantly better than reported data. Further, the film constitution indicated amplified antibacterial effectiveness against both Gram-positive (Listeria monocytogenes) and Gram-negative (Escherichia coli) bacteria and enhanced cell growth (145.5%) to thereby infer upon the potential associated with its application as a viable wound dressing film.


Subject(s)
Anti-Bacterial Agents/pharmacology , Citric Acid/chemistry , Glycerol/chemistry , Occlusive Dressings , Polyvinyl Alcohol/chemistry , Starch/chemistry , Escherichia coli/drug effects , Listeria monocytogenes/drug effects , Tensile Strength , Wound Healing
9.
Int J Biol Macromol ; 146: 70-79, 2020 Mar 01.
Article in English | MEDLINE | ID: mdl-31883901

ABSTRACT

This work addresses response surface methodology (RSM) design based investigations to obtain useful insights on the compatibility and synergy of quaternary formulations [variant macromolecular concentrations of starch (5-10 w/w%), polyvinyl alcohol (5-10 w/w%), citric acid (15-40 wt%) and glycerol (15-40 wt%)] and to yield wound dressing films with appropriate combinations of swelling index (SI), in-vitro degradation during 27 days and tensile strength (TS). The design studies inferred that while SI and in-vitro degradation followed quadratic expressions with respect to variations in the quaternary compositions, the TS was relatively less complex with bilinear and linear terms of the independent variables. Based on experimental investigations, optimized film (composition: 5 w/w% PVA, 10 w/w% St, 15 wt% CA and 15 wt% Gl) exhibited excellent SI (338.37%), acceptable in-vitro degradation (53.27%) and gel fraction (GF 34%), higher TS (7.65 MPa) and water solubility (66%) but poor elongation (9.13%). Further, the optimal composition based polymer composite film possessed promising antibacterial activity with gram-negative (Escherichia coli) and gram-positive (Listeria monocytogenes) bacteria to indicate its competence in terms of a durable and inexpensive biocompatible wound dressing film.


Subject(s)
Anti-Bacterial Agents/chemistry , Bandages , Citric Acid/chemistry , Glycerol/chemistry , Membranes, Artificial , Polyvinyl Alcohol/chemistry , Starch/chemistry , Escherichia coli/growth & development , Listeria monocytogenes/growth & development
10.
Heliyon ; 5(11): e02934, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31844774

ABSTRACT

Given a sizable proportion of bio-resource production in the North-east (NE) India and the need to enhance the shelf life of perishable horticultural regional produce, this work addresses the optimality of inexpensive oven and intermittent airflow assisted tray drying processes for Kolmou (Ipomoea aquatica Forssk.), Pui (Basella alba), Jatialao sak (Lagenaria siceraria leaves), Kolphul (Musa balbisiana Colla blossom), Kaskal (Musa splendida), green Komora (Benincasa hispida) and Posola (Musa balbisiana Colla pseudostem) vegetables of NE India. Characterization parameters for process parametric optimality include proximate analysis based evaluation of moisture content, yield, carbohydrate, crude protein, soluble protein, vitamin C, antioxidant activity, ash, crude fibre and fat content. For most vegetables, tray drying process performance is superior in terms of better moisture removal, higher yield and higher anti-oxidant activity. Among all considered samples, tray dried Kolmou possessed highest antioxidant activity. Vitamin C content was seen to be highest in tray dried Komora.

11.
Int J Biol Macromol ; 131: 998-1007, 2019 Jun 15.
Article in English | MEDLINE | ID: mdl-30914366

ABSTRACT

This work addresses the competence of PVA/starch/citric acid (PVA/St/CA) based composite films for wound dressing applications. Literature reported composition of PVA, starch and glycerol were adopted and the optimality of crosslinking temperature (40 to 60 °C) and citric acid concentration (0.5 to 3 g) have been investigated during solution casting based composite film fabrication. The prepared polymer films have been characterized with swelling index, solubility based biodegradability, gel fraction, mechanical strength, water vapor transmission rate and antimicrobial effectiveness. The optimized film (composition) were analyzed to possess excellent swelling (260.5 ±â€¯2.9%) and in-vitro degradation (45.5 ±â€¯1.8-59.8 ±â€¯0.4% degradation, during 14 days) characteristics. Further, the film possesses enhanced combinations of water vapor transmission rate and antibacterial activity with Gram-negative (Escherichia coli) and Gram-positive (Listeria monocytogenes) bacteria. With all these promising characteristics, the low temperature (50 °C) and long duration (12 h) fabricated PVA-St-CA films have been inferred to be a potential candidate for wound dressing applications.


Subject(s)
Biological Dressings , Citric Acid/chemistry , Glycerol/chemistry , Polyvinyl Alcohol/chemistry , Starch/chemistry , Anti-Bacterial Agents , Biocompatible Materials/chemistry , Chemical Phenomena , Disk Diffusion Antimicrobial Tests , Materials Testing , Permeability , Spectroscopy, Fourier Transform Infrared , Steam , Temperature , Tensile Strength
12.
Phys Chem Chem Phys ; 16(33): 17588-94, 2014 Sep 07.
Article in English | MEDLINE | ID: mdl-25025524

ABSTRACT

The electrochemical reduction of gaseous CO2 is studied for the first time using sterically hindered bulky quaternary ammonium ions in a solid polymer matrix at room temperature and atmospheric pressure in a developed electrochemical reactor. Some new insights are found, leading to an effective reaction process. It is found that the reaction zone can be tuned to a great extent with the help of fixed functional groups attached to the solid polymer. To illustrate the concept, solid polymer electrolytes with the same backbone and different fixed functional groups are synthesized. It is found that only a change to the functional group in the membrane is needed to dramatically change the efficiency and selectivity of the reaction products. Suitable groups may increase the mass transfer of CO2 at the reaction interface and help as a co-catalyst. This work may open a new approach for the development of next generation processes for gaseous CO2 electroreduction to fuels, which is a present need.

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