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1.
Nanotechnology ; 35(33)2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38759636

ABSTRACT

This research aims to develop relatively new membranes from starch biopolymer incorporated with different concentrations (0, 5, 10, 15, 20% w/w of solid starch) of chitosan nanoparticles (CNP) that can be used for water treatment. The membranes were fabricated using the solvent casting method while the CNP was produced using the ionic gelation method. The membranes were characterized in terms of morphology, porosity, water vapor permeability (WVP), and water contact angle. The application of the membranes to treat water was demonstrated on methylene blue solution because methylene blue is a commonly used dye in many industries. It was found that the starch/10% CNP membrane was the optimum membrane for methylene blue dye treatment because the membrane exhibits a smooth surface, high WVP (1.67 × 10-10g Pa-1h-1m-1), high porosity (59.92%), low water contact angle value (44.8°), and resulted in the highest percentage removal of methylene blue (94.0%) after the filtration. After filtration, the starch/10% CNP membrane was still in good condition without breakage. In conclusion, the starch/CNP membranes produced in this study are promising for sustainable and environmentally friendly water treatment, especially for water containing methylene blue dye. This research aligns with current thematic trends in bionanohybrid composite materials utilization, offering innovative solutions for addressing water pollution challenges.

2.
Carbohydr Polym ; 329: 121735, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38286535

ABSTRACT

Starch biopolymer films incorporated with chitosan nanoparticles (CNP) or starch/CNP films are promising alternatives to non-degradable food packaging materials. The films can be utilized for active food packaging applications because CNP exhibits antimicrobial and antioxidant properties, which can improve food shelf-life. Nonetheless, knowledge of the effects of CNP inclusion on the properties of starch films is not fully elucidated. This paper reviews the influences of various concentrations of CNP, sizes of CNP, and other additives on the mechanical, thermal, barrier, antimicrobial, antioxidant, biodegradability, and cytotoxicity properties of starch/CNP films as well as the mechanisms involved in relation to food packaging applications. The usage of starch/CNP films for active food packaging can help to reduce environmental issues and contribute to food safety and security.


Subject(s)
Anti-Infective Agents , Chitosan , Nanoparticles , Antioxidants/pharmacology , Starch , Food Packaging
3.
Int J Biol Macromol ; 212: 220-231, 2022 Jul 01.
Article in English | MEDLINE | ID: mdl-35597382

ABSTRACT

Active and pH-sensitive films of poly(lactic acid) (PLA)/nanofibrillated cellulose (NFC) have been fabricated and tested. The PLA and PLA/NFC films with 1.5% NFC were prepared via solvent casting method, with different loadings of essential oil (EO), including thymol and curry, being added at 5, 10, and 15%. The fixed content of anthocyanin powder (1%) was incorporated into the films as a pH indicator. The active PLA and PLA/NFC films were characterised on their physical, mechanical, thermal, and biodegradation properties. The addition of NFC reduced the tensile strength but increased the flexibility of films due to the plasticizing effect of EOs. The PLA/EO and PLA/NFC/EO films containing curry demonstrated a slightly higher strength than the films with thymol. The flexibility of films was increased at higher loading of EO regardless of the types of EO. The thermal profile demonstrated that the neat PLA film had a higher maximum degradation temperature than the active PLA/EO and PLA/NFC/EO films. The active PLA/EO and PLA/NFC/EO films containing anthocyanin successfully changed its colour in pH 2.0 and 14.0. The PLA/NFC films with thymol and anthocyanin formulation could inhibit fungus growth better in the cherry tomato sample than the PLA/NFC films with curry and anthocyanin.


Subject(s)
Food Packaging , Oils, Volatile , Anthocyanins , Cellulose/chemistry , Hydrogen-Ion Concentration , Oils, Volatile/chemistry , Polyesters/chemistry , Thymol
4.
Polymers (Basel) ; 13(23)2021 Nov 23.
Article in English | MEDLINE | ID: mdl-34883563

ABSTRACT

The application of starch films, such as food packaging materials, has been restricted due to poor mechanical and barrier properties. However, the addition of a reinforcing agent, cellulose nanofibers (CNF) and also thymol, into the films, may improve the properties of films. This work investigates the effects of incorporating different concentrations of thymol (3, 5, 7, and 10 wt.%) on physical, mechanical, water vapor barrier, and antibacterial properties of corn starch films, containing 1.5 wt.% CNF produced using the solvent casting method. The addition of thymol does not significantly affect the color and opacity of the films. It is found that the tensile strength and Young's modulus of the films decreases from 10.6 to 6.3 MPa and from 436.9 to 209.8 MPa, respectively, and the elongation at break increased from 110.6% to 123.5% with the incorporation of 10 wt.% thymol into the films. Furthermore, the addition of thymol at higher concentrations (7 and 10 wt.%) improved the water vapor barrier of the films by approximately 60.0%, from 4.98 × 10-9 to 2.01 × 10-9 g/d.m.Pa. Starch/CNF/thymol bionanocomposite films are also found to exhibit antibacterial activity against Escherichia coli. In conclusion, the produced starch/CNF/thymol bionanocomposite films have the potential to be used as antibacterial food packaging materials.

5.
Int J Biol Macromol ; 183: 1352-1361, 2021 Jul 31.
Article in English | MEDLINE | ID: mdl-34000310

ABSTRACT

This study explores the preparation of corn starch (CS) films incorporated with nanocellulose fiber (NCF) and different concentrations of thymol (0.1, 0.3, and 0.5% weight of thymol/volume of solution (% w/v)) via the solvent casting method. The resulting films were characterized by the functional chemistry, crystallinity, morphology, mechanical, thermal, and barrier properties. The Fourier transform infrared spectroscopy analysis confirmed the presence of intermolecular hydrogen bonding between the thymol and starch, as well as the thymol and glycerol, via hydroxyl groups of glycerol, starch, and thymol. The film crystallinity decreased with increasing concentration of thymol. The addition of NCF at 1.5% weight of starch increased the tensile strength (TS) and Young's Modulus (YM), but decreased the elongation at break (EAB), oxygen permeability, and water vapor permeability of the CS films. The thermal stability of the CS films was also improved with the addition of NCF. The addition of thymol to the CS/NCF bio-nanocomposite films decreased the TS and YM, respectively but increased the EAB due to the plasticizing effect of thymol. The addition of thymol also improved the thermal stability but reduced the barrier properties of the films. The effects on the mechanical, thermal, and barrier properties were more pronounced at higher concentrations of thymol. In conclusion, the inclusion of both NCF and thymol led to the improvement of the flexibility and thermal stability of the CS films.


Subject(s)
Cellulose/chemistry , Starch/chemistry , Thymol/chemistry , Biopolymers/chemistry , Elastic Modulus , Membranes, Artificial , Nanocomposites/chemistry , Permeability , Tensile Strength
6.
Polymers (Basel) ; 13(3)2021 Jan 27.
Article in English | MEDLINE | ID: mdl-33513664

ABSTRACT

This work aims to develop corn starch/chitosan nanoparticles/thymol (CS/CNP/Thy) bio-nanocomposite films as potential food packaging materials that can enhance the shelf life of food. CS/CNP/Thy bio-nanocomposite films were prepared by the addition of different concentrations of thymol (0, 1.5, 3.0, 4.5 w/w%) using a solvent casting method. The resulting films were characterized in terms of optical, mechanical, and water vapor permeability (WVP) properties. The addition of thymol was found to reduce the tensile strength (TS), elongation at break (EAB), and Young's modulus (YM) of the films. Generally, the increment in the concentration of thymol did not significantly affect the TS, EAB, and YM values. The addition of 1.5 w/w% thymol increased the WVP of the films but the WVP reduced with the increase in thymol concentrations. CS/CNP/Thy-3% bio-nanocomposite films demonstrated the potential to lengthen the shelf life of cherry tomatoes packed with the films, whereby the cherry tomatoes exhibited no significant changes in firmness and the lowest weight loss. In addition, no mold growth was observed on the sliced cherry tomatoes that were in direct contact with the films during 7 days of storage, proving the promising application of the films as active food packaging materials.

7.
Polymers (Basel) ; 12(11)2020 Nov 07.
Article in English | MEDLINE | ID: mdl-33171703

ABSTRACT

Food packaging has seen a growth in the use of materials derived from renewable resources such as poly(lactic acid) (PLA). However, the initial costs to produce bioplastics are typically high. Tropical fruit waste as naturally sourced fibres, such as jackfruit skin, can be used as a cost-reducing filler for PLA. The main objective in this study is to fabricate a low-cost natural fibre-reinforced polymer that potentially applies in packaging with the aid of bleaching treatment. The treatment shows a rougher surface fibre in Scanning electron microscopy (SEM) micrographs and it is expected to have better mechanical locking with the matrix, and this is found similar with a Fourier-transform infrared spectroscopy (FTIR) analysis. Unfortunately, fibre insertion does find low tensile performances, yet bleached-fibre composites improved its performance significantly. A similar situation was found in the thermal characterization where a low-thermal stability natural fibre composite has lower thermal behaviour and this increased with bleaching treatment. Besides, bleached-fibre composites have a longer service period. Besides, a 15 wt% thymol insertion inhibits the growth of Gram-positive bacteria in the composites and the non-treated fibre composite has better thymol effects. The 30 wt% of the bleached-fibre insertion composite has a high potential to reduce the cost of bioplastic products with minimum alterations of overall performances.

8.
Nanomaterials (Basel) ; 10(6)2020 May 30.
Article in English | MEDLINE | ID: mdl-32486281

ABSTRACT

This research investigated the effect of synthesis temperature on the size and shape of zinc oxide (ZnO) nanoparticles (NPs) synthesized using pineapple peel waste and antibacterial activity of ZnO NPs in starch films. Zinc oxide NPs synthesized at different temperatures were characterized by Fourier transform infrared spectroscopy, X-ray diffraction analysis, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy. Micrographs of ZnO NPs synthesized at 28 and 60 °C showed that synthesis temperature affected the sizes and shapes of ZnO NPs. The non-heated (28 °C) condition resulted in NPs with diameters in the range of 8-45 nm with a mixture of spherical and rod shapes, whereas the heated (60 °C) condition led to NPs with diameters in the range of 73-123 nm with flower rod shapes. The ZnO-starch nanocomposite films incorporated with 1, 3, and 5 wt.% ZnO NPs were prepared via a film casting method. The antibacterial activity of the films against Gram-positive and Gram-negative bacteria was investigated using the disc diffusion method. The results showed an increase in the inhibition zone for Gram-positive bacteria, particularly Bacillus subtilis, when the concentration of ZnO NPs incorporated in the film was increased from 1 to 5 wt.%.

9.
Carbohydr Polym ; 230: 115602, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31887886

ABSTRACT

Chitosan nanoparticles (CNP) were synthesized via ionic gelation and used for the preparation of starch-based nanocomposite films containing different concentration of CNP (0, 5, 10, 15, 20% w/w). Antimicrobial properties of starch/CNP films was evaluated via in vitro (disc diffusion analysis) and in vivo (microbial count in wrapped cherry tomatoes) study. It was found that inhibitory zone of the 15 and 20% of starch/CNP films were clearly observed for all the tested bacteria including Bacillus cereus, Staphylococcus aureus, Escherichia coli and Salmonella typhimurium. In vivo study revealed that the starch/CNP film (15% w/w) was more efficient to inhibit the microbial growth in cherry tomatoes (7 × 102 CFU/g) compared to neat starch film (2.15 × 103 CFU/g) thus confirmed the potential application of the films as antimicrobial food packaging.


Subject(s)
Anti-Infective Agents/chemistry , Chitosan/analogs & derivatives , Edible Films , Nanoparticles/chemistry , Starch/chemistry , Anti-Infective Agents/pharmacology , Food Packaging/methods , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects
10.
Int J Health Care Qual Assur ; 32(5): 887-908, 2019 Jun 10.
Article in English | MEDLINE | ID: mdl-31195926

ABSTRACT

PURPOSE: According to the literature concerned with this study, less than satisfactory outcomes have been achieved through implementing business process improvements methods (BPIMs) in industries, in general, and in healthcare, in particular. The existing methods used need to be enhanced in order to create more effective outcomes. There has also been a lack of studies documenting gaps or shortfalls in implementing BPIMs, to be presented to the BPI research community. Therefore, researchers of this paper have attempted to fill gaps between theory and practice. On the contrary, there is also a need to link practical outcomes in the healthcare domain with those of the BPI research community. The purpose of this paper is to review popular BPIMs, techniques and tools applied in the healthcare domain; it seeks to examine and highlight their significant roles, clarify their pros and cons, and find opportunities to enhance their impact on the achievement of more sustainable improvements in the healthcare domain. DESIGN/METHODOLOGY/APPROACH: This study has been carried out by using a methodology combining an in-depth literature review with a comparison framework, which is called as the "Framework for Comparing Business Process Improvement Methods." The framework is composed of seven dimensions and has been adapted from four recognized, related frameworks. In addition to the in-depth review of related literature and the adapted comparison framework, researchers have conducted several interviews with healthcare BPI practitioners in different hospitals, to attain their opinions of BPI methods and tools used in their practices. FINDINGS: The main results have indicated that significant improvements have been achieved by implementing BPIMs in the healthcare domain according to related literature. However, there were some shortfalls in the existing methods that need to be resolved. The most important of these has been the shortfall in representing and analyzing targeted domain knowledge during improvement phases. The tool currently used for representing the domain, specifically flowcharts, is very abstract and does not present the domain in a clear form. The flowchart tool also fails to clearly present the separation of concerns between business processes and the information systems processes that support a business in a given domain. PRACTICAL IMPLICATIONS: The findings of this study can be useful for BPI practitioners and researchers, mainly within the healthcare domain. The findings can help these groups to understand BPIMs shortfalls and encourage them to consider how BPIMs can be potentially improved. ORIGINALITY/VALUE: This researchers of this paper have proposed a comparison framework for highlighting popular BPIMs in the healthcare domain, along with their uses and shortfalls. In addition, they have conducted a deep literature review based on the practical results obtained from different healthcare institutions implementing unique BPIMs around the world. There has also been valuable interview feedback attained from BPI leaders of specific hospitals in Saudi Arabia. This combination is expected to contribute to knowledge of BPIMs from both theoretical and practical points of view.


Subject(s)
Health Facility Administration/standards , Quality Improvement , Efficiency, Organizational , Interviews as Topic , Qualitative Research , Total Quality Management
11.
PLoS One ; 12(4): e0176223, 2017.
Article in English | MEDLINE | ID: mdl-28445486

ABSTRACT

With the rapid development of technology, mobile phones have become an essential tool in terms of crime fighting and criminal investigation. However, many mobile forensics investigators face difficulties with the investigation process in their domain. These difficulties are due to the heavy reliance of the forensics field on knowledge which, although a valuable resource, is scattered and widely dispersed. The wide dispersion of mobile forensics knowledge not only makes investigation difficult for new investigators, resulting in substantial waste of time, but also leads to ambiguity in the concepts and terminologies of the mobile forensics domain. This paper developed an approach for mobile forensics domain based on metamodeling. The developed approach contributes to identify common concepts of mobile forensics through a development of the Mobile Forensics Metamodel (MFM). In addion, it contributes to simplifying the investigation process and enables investigation teams to capture and reuse specialized forensic knowledge, thereby supporting the training and knowledge management activities. Furthermore, it reduces the difficulty and ambiguity in the mobile forensics domain. A validation process was performed to ensure the completeness and correctness of the MFM. The validation was conducted using two techniques for improvements and adjustments to the metamodel. The last version of the adjusted metamodel was named MFM 1.2.


Subject(s)
Cell Phone , Forensic Sciences/methods , Models, Theoretical , Algorithms , Crime
12.
PLoS One ; 12(2): e0170793, 2017.
Article in English | MEDLINE | ID: mdl-28146585

ABSTRACT

Database Forensics (DBF) is a widespread area of knowledge. It has many complex features and is well known amongst database investigators and practitioners. Several models and frameworks have been created specifically to allow knowledge-sharing and effective DBF activities. However, these are often narrow in focus and address specified database incident types. We have analysed 60 such models in an attempt to uncover how numerous DBF activities are really public even when the actions vary. We then generate a unified abstract view of DBF in the form of a metamodel. We identified, extracted, and proposed a common concept and reconciled concept definitions to propose a metamodel. We have applied a metamodelling process to guarantee that this metamodel is comprehensive and consistent.


Subject(s)
Databases, Factual , Forensic Sciences , Models, Theoretical , Forensic Sciences/methods , Humans , Reproducibility of Results
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