Visible light-activated dye-sensitized TiO antibacterial film: A novel strategy for enhancing food safety and quality.

Antibacterial packaging holds promise in addressing food spoilage by inactivating bacteria, but current antimicrobial packaging solutions face challenges like depletion of antibacterials and concerns of antibiotic abuse. In response to these limitations of existing packaging materials, we developed a novel antibacterial packaging film by incorporating titanium dioxide (TiO)- tetra(4-carboxyphenyl) porphyrin (TcPP) conjugates into cellulose nanofibrils (CNF) films. Unlike conventional antimicrobial packaging, this film harnesses visible light energy to excite electrons from TcPP to TiO, generating reactive oxygen species (ROS) that inactivate bacteria without relying on antibiotics.

Synthesis and Characterization of Poly(Butylene Sebacate-o-Terephthalate) Copolyesters with Pentaerythritol as Branching Agent.

Poly(butylene sebacate-co-terephthalate) (PBSeT) copolyesters are prepared by melt polymerization via two-step transesterification and polycondensation using pentaerythritol (PE) as a branching agent. The effects of the incorporated PE on its chemical, thermal, mechanical, and degradation properties, along with the rheological properties of its melt, are investigated. The highest molecular weight and intrinsic viscosity along with the lowest melt flow index were achieved at a PE content of 0.

TEMPO-Oxidized Cellulose Nanofibril Films Incorporating Graphene Oxide Nanofillers.

To design a new system of novel TEMPO-oxidized cellulose nanofibrils (TOCNs)/graphene oxide (GO) composite, 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidation was utilized. For the better dispersion of GO into the matrix of nanofibrillated cellulose (NFC), a unique process combining high-intensity homogenization and ultrasonication was adopted with varying degrees of oxidation and GO percent loadings (0.4 to 2.

A New Method to Determine Antioxidant Activities of Biofilms Using a pH Indicator (Resazurin) Model System.

Biopolymeric films were prepared with gelatin, plasticizer, and three different types of antioxidants (ascorbic acid, phytic acid, and BHA) corresponding to different mechanisms in activity. The antioxidant activity of films was monitored for 14 storage days upon color changes using a pH indicator (resazurin). The instant antioxidant activity of films was measured by a DPPH free radical test.

Grape pomace and its secondary waste management: Biochar production for a broad range of lead (Pb) removal from water.

Grape pomace (GP) management has been a challenge worldwide. We have previously demonstrated a biorefinery process to recover oil and polyphenols, and produce biofuels from GP sequentially, although over 50% of GP solid waste remains post-processing. To approach zero solid waste during GP processing, herein a pyrolysis process was designed for converting GP and its secondary processing wastes to biochars, which were then evaluated for lead (Pb) adsorption from water.

Compositional Characterization of Different Industrial White and Red Grape Pomaces in Virginia and the Potential Valorization of the Major Components.

To better evaluate potential uses for grape pomace (GP) waste, a comprehensive chemical composition analysis of GP in Virginia was conducted. Eight commercial white and red pomace samples (cv. Viognier, Vidal Blanc, Niagara, Petit Manseng, Petit Verdot, Merlot, Cabernet Franc, and Chambourcin) obtained from different wineries in Virginia, USA were used.

Exploration of hybrid nanocarbon composite with polylactic acid for packaging applications.

Polylactic acid (PLA) nanocomposite films were fabricated with graphene oxide (GO) and single-walled carbon nanotubes (CNT) as a hybrid-co-filler with GOCNT fraction varying from 0.05 to 0.4% by weight.

Utilization of Lignin in Biopolymeric Packaging Films.

Lignin is a byproduct of agricultural industries and only has limited applications. In this study, lignin was investigated for use in sustainable biopolymeric packaging film. Alkali lignin (AL) and lignosulfonate (LSS) were added to enzymatically modified soy protein isolate (SPI) biopolymeric film with different concentrations with the goal of improvement of film physical and functional properties.

Lignin-Based Biopolymeric Active Packaging System for Oil Products.

Antioxidant activity of enzymatically modified soybean protein film with two different forms of added lignin (alkali lignin and lignosulfonate) was investigated using two stimulated food systems involving direct and indirect contact with soybean oil and fish fatty acid ethyl ester (FAEE). For the direct system, control and lignin-doped films were added to oil vials which were stored at dark under 40 °C whereas for indirect, films were used to cover oil-containing glass vials stored under standard commercial lighting conditions. Autoxidation of oil samples in the direct contact system was determined by peroxide value (PV), color, headspace oxygen, and volatile compounds, while for the indirect contact system photoxidation was determined by using PV and color.

Self-enzyme chemiluminescence immunoassay capable of rapidly diagnosing the infection of influenza A (H1N1) virus.

A highly sensitive self-enzyme immunoassay with 1,1'-oxalyldiimidazole chemiluminescence (ODI-CL) detection was developed for the first time to quantify influenza A (H1N1) virus. A specific capture antibody, capable of capturing hemagglutinin (HA) subtypes of H1N1, was immobilized on the surface of the magnetic Au-FeO nanocomposite. Neuraminidase (NA) subtype of H1N1 was acts as an enzyme in the self-enzyme immunoassay.

Evaluation of Enzymatically Modified Soy Protein Isolate Film Forming Solution and Film at Different Manufacturing Conditions.

Unlabelled: The effects of transglutaminase on soy protein isolate (SPI) film forming solution and films were investigated by rheological behavior and physicochemical properties based on different manufacturing conditions (enzyme treatments, enzyme incubation times, and protein denaturation temperatures). Enzymatic crosslinking reaction and changes in molecular weight distribution were confirmed by viscosity measurement and SDS-PAGE, respectively, compared to 2 controls: the nonenzyme treated and the deactivated enzyme treated. Films treated with both the enzyme and the deactivated enzyme showed significant increase in tensile strength (TS), percent elongation (%E), and initial contact angle of films compared to the nonenzyme control film due to the bulk stabilizers in the commercial enzyme.

Improved thermal stability of polylactic acid (PLA) composite film via PLA-β-cyclodextrin-inclusion complex systems.

The effects of the incorporation of PLA-β-cyclodextrin-inclusion complex (IC) and β-cyclodextrin (β-CD) on biopolyester PLA films were investigated. Thermal stability, surface morphology, barrier, and mechanical properties of the films were measured at varying IC (1, 3, 5, and 7%) and β-CD (1 and 5%) concentrations. The PLA-IC-composite films (IC-PLA-CFs) showed uniform morphological structure, while samples containing β-CD (β-CD-PLA-CFs) showed high agglomeration of β-CD due to poor interfacial interaction between β-CD and PLA moieties.

Rapid and simple G-quadruplex DNA aptasensor with guanine chemiluminescence detection.

Cost-effective and sensitive aptasensor with guanine chemiluminescence detection capable of simply quantifying thrombin in human serum was developed using thrombin aptamer (TBA), one of the G-quadruplex DNA aptamers, without expensive nanoparticles and complicated procedures. Guanines of G-quadruplex TBA-conjugated carboxyfluorescein (6-FAM) bound with thrombin do not react with 3,4,5-trimethoxylphenylglyoxal (TMPG) in the presence of tetra-n-propylammonium hydroxide (TPA), whereas guanines of free TBA- and TBA-conjugated 6-FAM immobilized on the surface of graphene oxide rapidly react with TMPG to emit light. Thus, guanine chemiluminescence in 5% human serum with thrombin was lower than that without thrombin when TBA-conjugated 6-FAM was added in two samples and incubated for 20 min.

Evidence of multiple pathways capable of emitting peroxyoxalate chemiluminescence using a charge coupled device spectrometer.

Peroxyoxalate chemiluminescence (PO-CL) spectra obtained simultaneously and continuously using a CCD spectrometer provide evidence of the complexity of PO-CL reactions.

Rapid monitoring of alkaline phosphatase in raw milk using chemiluminescence detection.

A simple biosensor with 1,1'-oxalyldiimidazole chemiluminescence (ODI-CL) detection capable of rapidly quantifying and screening alkaline phosphatase (ALP) in raw and pasteurized milk was developed as an indicator for confirming whether commercial milk is properly pasteurized. Fluorescein was formed when standards containing 1.0% milk with different activities of ALP and samples containing 1.

Rapid quantification of melamine in milk using competitive 1,1'-oxalyldiimidazole chemiluminescent enzyme immunoassay.

A novel competitive 1,1'-oxalyldiimidazole (ODI) chemiluminescent enzyme immunoassay (CLEIA) was developed as a method for rapid and simple screening of melamine in milk. Fat existing in milk acts as an inhibitor in the competitive binding interaction of melamine and anti-melamine in the presence of melamine-conjugated horseradish peroxidase. Thus, the calibration curve and sensitivity of competitive ODI CLEIA for the quantification of melamine in fat free milk were wider and better than those in milk containing fat.

Microfluidic device capable of sensing ultrafast chemiluminescence.

Based on the principle of liquid core waveguide, a novel microfluidic device with micro-scale detection window capable of sensing flashlight emitted from rapid 1,1'-oxalyldi-4-methylimidazole (OD4MI) chemiluminescence (CL) reaction was fabricated. Light emitted from OD4MI CL reaction occurring in the micro-dimensional pentagonal detection window (length of each line segment: 900.0 microm, depth: 50.

New approach for characterization of gelatin biopolymer films using proton behavior determined by low field 1H NMR spectrometry.

The behavior of protons in biopolymer films (BFs) formed with gelatin, water, and glycerol was investigated at various relative humidities (RHs) and concentrations of glycerol using a low field 1H NMR spectrometer. At a RH of approximately 0%, the distributed spin-spin relaxation times (T2) of protons in BFs showed two components: a rapidly relaxing proton with the shortest T2 derived from protons in the rigid backbone of the gelatin polymer such as CH1-, CH2-, and CH3-, and a slowly relaxing component with longer T2 from protons of the functional groups in amino acid residues in gelatin such as -OH, -COOH, and -NH3. These two components are referred to as nonexchangeable (T2N) and exchangeable protons (T2E), respectively, indicating the different mobility of the protons.