Developing the biodegradable and renewable materials in the food packaging industry has become one of the most important topics in modern society, where has attracted a lot of efforts in this field. ...In this review, we have discussed the additives that used to regulate the mechanical and antimicrobial properties by blending into cellulose and its derivatives. Cellulose is one of the best biomass composites for film formation with resource abundance and biodegradability. To realize the further benefits of cellulose and its derivatives in the food packaging manufacture, there are still a quantity of opportunities in improving the practicality and cost of the additives.
The nanocomposites of reduced graphene oxide (RGO) and polyoxometalates (POMs) have been considered to be effective to boost more Li
+
to participate in intercalation/deintercalation process of ...lithium-ion batteries (LIBs). In this paper, a nanocomposite (PMo
12
@RGO-AIL) with electrostatic interaction of RGO and Keggin-type PMo
12
O
40
3−
has been fabricated and characterized by XRD, XPS, SEM, and TEM. To prepare PMo
12
@RGO-AIL, a strategy of covalent modification is developed between amino-based ionic liquid and RGO, helping to achieve the uniform dispersion of PMo
12
O
40
3−
. When the PMo
12
@RGO-AIL was used as a cathode for LIBs, it could exhibit more excellent reversible capacity, cycle stability, and rate capability than those of samples without modifying by ionic liquids.
Mycotoxins are secondary metabolites produced by fungi. These contaminate dried seafoods during processing and storage and represent a potential health hazard for consumers. A sensitive, selective ...and accurate liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was established for simultaneous quantification of four common mycotoxins (aflatoxin B1 (AFB1), T-2 toxin (T-2), ochratoxin A (OTA) and deoxynivalenol (DON)) in dried shrimp, dried fish and dried mussel products. Mycotoxins were extracted from dried seafood samples by acetonitrile/water (85/15, v/v), subjected to ultrasound for 60 min at 20 °C and cleaned up by defatting with n-hexane. The sample matrix affected the linearity of detection (R2 ≥ 0.9974). The limit of detection (LOD) and limit of quantification (LOQ) in dried seafood products varied from 0.1 to 2.0 µg·kg−1 and 0.3 to 5.0 µg·kg−1, respectively. The method was validated by spiking samples with specific mycotoxin levels, and the recoveries, intra-relative standard deviation (RSDs) and inter-RSDs ranged between 72.2–98.4%, 2.8–10.6%, and 5.5–15.4%, respectively. This method was used to analyze 40 dried seafood products purchased from the Zhanjiang seafood market. Results of this product sampling showed that while no DON was detected, AFB1, T-2 and OTA were detected in 30.8%, 17.5% and 33.3% of the samples, respectively. AFB1, T-2 and OTA concentrations varied at 0.58–0.89, 0.55–1.34 and 0.36–1.51 µg·kg−1, respectively. Relatively high frequency of contamination and the presence of AFB1, OTA and T-2 residues indicate the need to monitor mycotoxins in dried seafood products.
(Vp), a major food-borne pathogen, is responsible for severe infections such as gastroenteritis and septicemia, which may be accompanied by life-threatening complications. While studies have ...evaluated factors that affect the virulence of the pathogen, none have investigated the interaction of Vp with gut microbiota. To address this knowledge gap, we compared the effect of Vp on gut bacterial community structure, immunity, liver and kidney function, in pseudo germ-free (PGF) mice and normal (control) mice. Significant damage to the ileum was observed in normal mice compared with the PGF mice. The inflammatory factors IL-1β, IL-6, and TNF-α in normal mice were ∼2.5-fold higher than in the PGF mice, and liver (ALT, AST, ALP) and kidney (BUN) function indices were ∼1.6-fold higher. The Vp infection substantially reduced species composition and richness of the gut microbial communities. In particular, there was a shift in keystone taxa, from protective species of genera
,
,
, and
in the gut of control mice to opportunistic pathogens
,
,
, and
in Vp-infected mice, thus affecting microbiota-related biological functions in the mice. Specifically, pathways involved in infectious diseases and ion channels were significantly augmented in infected mice, while the pathways involved in metabolism, digestion and cell growth declined. We propose that the normal mice are more prone to Vp infection because of the alteration in gut-microbe-mediated functions. All these effects reduce intestinal resistance, with marked damage to the gut lining and pathogen leakage into the blood culminating in liver and kidney damage. These findings greatly advance our understanding of the mechanisms underlying interactions between Vp, the gut microbiota and the infected host.
Free amino acids (AAs) formed in fermented meat products are important nitrogen sources for the survival and metabolism of contaminating fungi. These AAs are mainly regulated by the TORC1-
signaling ...pathway.
spp., a common contaminant of fermented products, is a potential threat to food safety. Therefore, there is an urgent need to clarify the effect of different AAs on
spp. growth and metabolism. This study investigated the effect of 18 AAs on
(Fo17) growth, sporulation, T-2 toxin (T-2) synthesis and
expression through
gene regulation. Co-immunoprecipitation and Q Exactive LC-MS/MS methods were used to detect the interacting protein of Tap42 during specific AA treatment.
positively regulated L-His, L-Ile and L-Tyr absorption for Fo17 colony growth. Acidic (L-Asp, L-Glu) and sulfur-containing (L-Cys, L-Met) AAs significantly inhibited the Fo17 growth which was not regulated by
. The L-Ile and L-Pro addition significantly activated the sporulation of ΔFo
L-His and L-Ser inhibited the sporulation of ΔFo
. In T-2 synthesis, ΔFo
was increased in GYM medium, but was markedly inhibited in L-Asp and L-Glu addition groups. Dose-response experiments showed that 10-70 mg/mL of neutral AA (L-Thr) and alkaline AA (L-His) significantly increased the T-2 production and
expression of Fo17, but
expression was not activated in ΔFo
. Inhibition of T-2 synthesis and
expression were observed in Fo17 following the addition of 30-70 mg/mL L-Asp. KEGG enrichment pathway analysis demonstrated that interacting proteins of Tap42 were from glycerophospholipid metabolism, pentose phosphate pathway, glyoxylate and dicarboxylate metabolism, glycolysis and gluconeogenesis, and were related to the MAPK and Hippo signaling pathways. This study enhanced our understanding of AA regulation in fermented foods and its effect on
growth and metabolism, and provided insight into potential ways to control fungal contamination in high-protein fermented foods.
The present study focused on the determination of color, flavor, taste, and volatile organic compounds (VOCs) changes of shrimp paste fermented for 1, 2, 3, and 8 years by E-nose, E-tongue, and ...headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS). During fermentation, the color of shrimp paste turned dark brown with decreases in L*, a*, and b* values. Inorganic sulfide odor was dominant in all fermented samples. The umami, richness, and aftertaste-B reached a maximum in year 3 of fermentation. A total of 182 volatiles, including long-chain alkanes, esters, aldehydes, olefins, ketones, acids, furans, and pyrazines, were detected. Sixteen VOCs including dimethyl disulfide, methional, trimethyl-pyrazine, (E,E)-2,4-heptadienal, benzeneacetaldehyde were selected as flavor markers. Correlation analysis showed that 94 VOCs were related to saltiness while 40, 17, 21, 22, and 24 VOCs contributed to richness, umami, aftertase-B, sourness, and bitterness, respectively. These novel data may help in optimizing fermentation duration to achieve target flavor indicators in opossum shrimp paste production.
Fusarium oxysporum is ubiquitous and can easily contaminate food during processing and storage, potentially producing T-2 toxin, which can pose a severe health risk to public health. Previous ...research on the presence of T-2 has focused on starch-rich foods, while protein- and amino acid-rich foods have received relatively little attention. In this study, the effects of amino acids on the growth of F. oxysporum and its T-2 production were investigated by gene deletion and complementation experiments. The results showed that amino acids, including aspartic acid, methionine, isoleucine, serine, phenylalanine, and cysteine, significantly inhibited the growth of F. oxysporum, while promoting T-2 synthesis, with cysteine having the most pronounced effect. The target of rapamycin complex 1 (TORC1) is a key pathway in response to a variety of amino acids, including cysteine.
and
were found to be negative regulators of T-2 synthesis. The study highlights the elevated risk of T-2 production by F. oxysporum in cysteine-rich foods and the need to take appropriate measures to prevent and control the potential harm that such foods may present to public health.
F. oxysporum and its T-2 contamination of food not only leads to food wastage but also poses a major food safety challenge to humans. The growth and T-2 production characteristics of F. oxysporum in high-protein substrates are considerably different from those in grains. Here, we show that the abundant free amino acids in a protein-rich food matrix are a key regulatory factor for the growth of, and toxin production by, F. oxysporum. Cysteine has the most pronounced effect on inhibiting mycelial growth and promoting T-2 synthesis through the TORC1 pathway. This implies that consumers tend to overlook T-2 contamination due to the poor growth of F. oxysporum in food rich in protein and amino acids, especially cysteine. Therefore, particular attention should be paid to the protection of those products.
(
) is a common contaminant of dried fish, and the T-2 synthesis by this organism in dried fish products poses a serious public health risk. In this study, we investigated the effects of iturin A, a ...cyclic lipopeptide produced by
, on the growth and synthesis of the T-2 toxin of
, and transcriptomics was conducted. Results showed that the inhibitory effect of iturin A on
was significantly enhanced with an increase in iturin A concentrations. More specifically, compared with the control group, all indexes in the iturin A treatment group with 50 μg/mL were decreased to 24.84 mm, 0.33 × 10
cfu/mL, and 5.86 ng/mL for the colony diameter, number of spores, and concentration of T-2 toxin, respectively. Furthermore, iturin A was proven to destroy the integrity of cell membranes and cause a significant increase in ROS at 25 μg/mL or 50 μg/mL. Transcriptomic analysis revealed that with the treatment of iturin A, the genes of the oxidation-reduction process were up-regulated, while the gene expression of mycelial growth, cell integrity, transmembrane transport, energy metabolism, and others were down-regulated. More importantly, the
gene cluster was significantly inhibited. This study provided new insights into the mechanism for the inhibitory effect of iturin A on the growth and T-2 toxin synthesis of
and theoretical guidance for the application of iturin A in the preservation of dried aquatic products.
Two strains of Vibrio parahaemolyticus (ATCC 17802 and 33847) in shrimp, oyster, freshwater fish, pork, chicken and egg fried rice were evaluated for production of hemolysin and exoenzymes of ...potential importance to the pathogenicity of this bacterium.
The two strains of V. parahaemolyticus produced hemolysin, gelatinase, caseinase, phospholipase, urease, DNase and amylase in selected food matrices. Significantly higher (p < 0.05) hemolytic activity was produced by V. parahaemolyticus in egg fried rice > shrimp > freshwater fish > chicken > oyster > pork. But the exoenzyme activities were not consistent with the hemolytic activity profile, being significantly higher (p < 0.05) in shrimp > freshwater fish > chicken > oyster > pork > egg fried rice. Filtrates of V. parahaemolyticus from shrimp, freshwater fish and chicken given intraperitoneally to adult mice induced marked liver and kidney damage and were highly lethal compared with the filtrates of V. parahaemolyticus from oyster > egg fried rice > pork.
From in vitro and in vivo tests, it appears that the food matrix type has a significant impact on the activity of extracellular products and the pathogenicity of V. parahaemolyticus. From a food safety aspect, it is important to determine which food matrices can stimulate V. parahaemolyticus to produce additional extracellular factors. This is the first report of non-seafood including freshwater fish and chicken contaminated with V. parahaemolyticus to have been shown to be toxic to mice in vivo.
Plastics, accumulating globally as microplastics in living organisms, significantly contribute to environmental issues. Current materials like polylactic acid and commercial paper face limitations ...due to inadequate heat and water resistance, resulting in various practical inconveniences. This study reports a high-strength, water-resistant, recyclable, and naturally degradable pure cellulose food packaging material, which is crafted from bacterial cellulose (BC) and ethyl cellulose (EC) by a straightforward filtration and scratch coating process. The use of the EC ethanol solution eliminates the need for additional binders. Remarkably, the EC-BC pure cellulose material exhibits excellent mechanical properties (tensile strength of 195.3 ± 23.2 MPa), a stability in liquid environments (136.9 ± 24.2 MPa mechanical strength after 30 minutes of immersion in water), recyclability, natural degradability, cost-effectiveness, and non-toxicity. These attributes position binder-free hybrid designs, based on cellulose structures, as a promising solution to address environmental challenges arising from the extensive use of single-use plastics.
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