Identification and assessment of residual levels of the main oxidation product of tert-butylhydroquinone in frying oils after heating and its cytotoxicity to RAW 264.7 cells

Cytotoxic and genotoxic effects of tert-butylhydroquinone, butylated hydroxyanisole and propyl gallate as synthetic food antioxidants

Synthetic food antioxidants such as tert-butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA), and propyl gallate (PG) have been extensively utilized in different food industries because of their high protectant activities to stop food spoilage and remove foodborne diseases in humans and animals. It would be emphasized that increasing the intake of antioxidants through intracellular may lead to cyto/genotoxicity, and their complex formation with biological molecules eventually accelerate the progress of various diseases like multiple sclerosis, diabetes, neurological disorders, cardiac vascular disease, cancer, etc. Therefore, their toxicity is one of the challenging subjects due to their extensive use in food-related industries. TBHQ, BHA, and PG antioxidants have cytotoxic, genotoxic, and carcinogenic effects if absorbed in high doses through the gastrointestinal tract. Thermodynamic parameters presented that the hydrophobic bind plays a key role in the complexation of the TBHQ, BHA, and PG with albumin. The molecular modeling results showed that subdomain IIA plays a vital role in the interaction of TBHQ and BHA with albumin. To comprehend the mechanisms of the cyto/genotoxicity effects of these food antioxidants and conformational alterations of albumin macromolecule, we aim to overview numerous types of research that evaluated the cyto/genotoxicity effects of these antioxidants using several procedures.

Influence and mechanism of food matrices onto the TBBQ-eliminated performance during in-vitro digestion

Food matrices greatly impact TBBQ content during digestion, while lacking sufficient research and understanding. This study investigated the influence and mechanism of fried foods on the TBBQ-eliminated performance during in-vitro digestion. The results indicated that TBBQ content varied significantly among food matrices after in-vitro digestion, with the highest in peanuts (38.3%). The correlation analysis revealed that proteins remarkably facilitated TBBQ-eliminations while fats decreased the TBBQ-eliminated rate. The TBBQ-eliminated performance of proteins, protein digestive mixtures, and amino acids uncovered that sulfhydryl groups were crucial reactive groups to eliminate TBBQ, and TBBQ-eliminated rates under intestinal pH (8.0) were faster than gastric pH (1.5). Additionally, fats significantly reduced the protein-triggered TBBQ-eliminations, originating that the oil-water interface increased the interaction difficulty between lipophilic TBBQ and proteins. Thus, this work provided an in-depth understanding of food matrices (especially proteins and fats) in TBBQ eliminations to enlighten the promising TBBQ-risk-reduced strategies with high-protein and low-fat foods.

Nanozyme-integrated alcogel colorimetric sensor for rapid and on-site detection of tert-butyl hydroquinone

Tert-butyl hydroquinone (TBHQ) stand as one of the most widely used antioxidants in food and daily chemical products. Rapid and sensitive monitoring of TBHQ holds considerable importance in safeguarding human health due to its potential risks. In this study, we devised an alcogel-based colorimetric sensor enabling the portable and visual detection of TBHQ. The Ce-UiO-66 nanozyme exhibiting remarkable oxidase-like activity, was synthesized and characterized, facilitating the catalysis of TBHQ oxidation to 2-tert-butyl-1,4-benzoquinone (TBBQ). The ensuing chromogenic reaction between TBBQ and ethylenediamine produced a stable and colored product, serving as a reliable indicator for the rapid and specific detection of TBHQ. Building upon this discovery, a portable and low-cost colorimetric sensor was fashioned by integrating the nanozyme into κ-carrageenan alcogel, thereby enabling on-site TBHQ detection via a smartphone-based sensing platform. The colorimetric sensor exhibited a detection limit of 0.8 μg mL-1, demonstrating robust performance across various matrices such as edible oils, cosmetics, and surface water. Recoveries ranged from 84.9 to 95.5%, with the sensor's accuracy further validated through gas chromatography-mass spectrometry. Our study presents an effective approach to rapid and convenient monitoring of TBHQ, exhibiting good extensibility and practicability.

Synthesis, Characterization and Evaluation of a Novel Tetraphenolic Compound as a Potential Antioxidant

A novel antioxidant containing four hydroxyl groups, namely 2,2'-(2-methylpropane-1,3-diyl)bis(hydroquinone) (MPBHQ), was synthesized using hydroquinone and methylallyl alcohol as the raw materials, phosphoric acid as the catalyst, and toluene as the solvent system. The structure of MPBHQ was characterized by mass spectrometry, nuclear magnetic resonance, ultraviolet spectroscopy, and infrared spectroscopy. The results showed that MPBHQ has a good radical scavenging effect, as measured by the ORAC assay, DPPH radical scavenging assay, ABST radical scavenging assay, and Rancimat test. In fatty acid methyl ester and lard without exogenous antioxidants, MPBHQ showed better antioxidant performance than butylated hydroxytoluene (BHT), hydroquinone (HQ), tert-butyl hydroquinone (TBHQ), and propyl gallate (PG), meeting the need for a new antioxidant with better properties to ensure the oxidative stability of lipids and biodiesel.

Porous carbon derived from ZIF-8 modified molecularly imprinted electrochemical sensor for the detection of tert-butyl hydroquinone (TBHQ) in edible oil

In this manuscript, ZIF-8 derived nanoporous carbon material (ZC) was prepared and used as modification material to construct a molecularly imprinted electrochemical sensor for the direct detection of tert-butyl hydroquinone (TBHQ) in edible oil. Electrochemical characterizations, scanning electron microscopy and X-ray diffraction show that ZC has excellent conductivity, high electrochemical active area and stable porous framework structure. Using TBHQ as template and o-phenylenediamine as functional monomer, the sensor was constructed. Experimental parameters such as the number of polymerization cycle, polymerization speed, and pH of the measured solution, removal and rebinding time were studied. Under optimized conditions, the prepared sensor showed a wider linear range from 1.0 μmol L^-1 to 75.0 μmol L^-1 with the detection limit of 0.42 μmol L^-1 (S/N = 3). Meanwhile, the sensor also expressed good selectivity, repeatability, reproducibility, stability and successfully applied for the determination of TBHQ in real edible oil, giving satisfactory results.

Distribution of 2-tert-butyl-1,4-benzoquinone and its precursor, tert-butylhydroquinone, in typical edible oils and oleaginous foods marketed in Hangzhou City, China

This study aimed to obtain a reliable evaluation about addition of tert-butylhydroquinone (TBHQ), and distribution of TBHQ and 2-tert-butyl-1,4-benzoquinone (TBBQ) contents in typical edible oils and oleaginous foods marketed in Hangzhou City. Briefly, the probability of labeled with addition of TBHQ in foods decreased from 36.45 ± 2.6% to 28.78 ± 3.7% in the period from 2018 to 2020. In the 135 analyzed samples, TBHQ contents were far less than the maximum legal additive amount, and TBBQ contents ranged from below its limit of quantification (LOQ) to 13.54 ± 1.15 mg/kg. The conversion rate from TBHQ to TBBQ in edible oils was 2.94 ± 1.17%, much lower than that in other food categories. Further research determined that the process method and food composition were the main factors for different conversion rates from TBHQ to TBBQ in various food categories. In addition, oil consumption was found to be the primary source of dietary intake of TBHQ and TBBQ.

Astragaloside IV, a saponin from Astragalus membranaceus var. mongholicus, induces expressions of heme recycle proteins via signaling of Nrf2/ARE in cultured macrophages

ETHNOPHARMACOLOGICAL RELEVANCE

In traditional Chinese medicine (TCM) theory, "Qi" is classified as energetic essence supporting the life activities in human. "Blood" is categorized as nourishing essence and circulating in the body. "Blood" and "Qi" have an intimate relationship. Astragali Radix (AR; root of Astragalus membranaceus (Fisch.) Bge. Var. mongholicus (Bge.) Hsiao) has a broad spectrum of application for "Qi-Blood" enrichment. Astragaloside IV, a major saponin in AR, has therapeutic functions in erythropoietic, cardiovascular and immune systems. However, the efficacy of astragaloside IV in erythrophagocytosis has not been elucidated.

AIM OF THE STUDY

The possible functions of astragaloside IV in heme iron recycling during erythrophagocytosis in cultured macrophage were elucidated.

METHODS

The translational and transcriptional expressions of heme recycling enzymes were determined after incubating of astragaloside IV for 24 h in cultured macrophage.

RESULTS

In astragaloside IV-treated macrophage, the expressions, both RNA and protein levels, of regulators of heme recycling, e.g. heme oxygenase-1 (HO-1), ferroportin (FPN), biliverdin reductase A and B (BVRA, BVRB), were markedly induced in dose-dependent manners. In parallel, the transcriptional activity of antioxidant response element, cloned within an expression vector as pARE-Luc and transfected in cultured macrophages, was markedly induced after a challenge with astragaloside IV in a dose-dependent manner. Moreover, the translocation of Nrf2, a transcriptional factor in regulating expression of heme recycling protein, was induced by astragaloside IV, leading to an enrichment at nucleus fraction.

CONCLUSION

Astragaloside IV shed lights in enhancing the expression of heme recycle proteins via Nrf2/ARE signaling pathway.

Simple synthesis of a clew-like tungsten carbide nanocomposite decorated with gold nanoparticles for the ultrasensitive detection of tert-butylhydroquinone

The excessive use of food additives in manufactured food products negatively affects their quality and potentially impacts human health. In the present study, a composite consisting of gold nanoparticles decorated on tungsten carbide (AuNP-WC) was successfully fabricated using a facile and cost-effective ultrasonication technique. Compared to a bare glassy carbon electrode (GCE), AuNP-GCE, and WC-GCE, the AuNP-WC-GCE demonstrated excellent sensing performance for tert-butylhydroquinone (TBHQ) when used as an electrocatalyst in 0.05 M phosphate buffer solution (PBS), with a low working potential and a high peak current. In particular, the composite was able to detect the oxidation of TBHQ within a linear concentration range of 5 to 75 nM, with an extremely low detection limit of 0.20 nM. The practicability of the sensor was also assessed in the analysis of TBHQ in real samples of soybean oil, blended oil, and red wine, with satisfactory recovery rates obtained.

tert-Butyl-p-benzoquinone induces autophagy by inhibiting the Akt/mTOR signaling pathway in RAW 264.7 cells

tert-Butyl-p-benzoquinone (TBBQ), a metabolite of tert-butylhydroquinone from food, has cytotoxicity, the underlying mechanism of which is not clear. In this study, the viability of RAW 264.7 cells exposed to TBBQ at concentrations of 0.5-10 μg mL^-1 was assayed by MTT. Results suggest that TBBQ decreased the viability in a dose-dependent manner. Monodansylcadaverine (MDC) staining results indicate the occurrence of autophagy induced by TBBQ, which was manifested by activation of LC3-II concurrent with the increased levels of Beclin1 and reduced levels of p62. Elevated lipid peroxide and decreased SOD activity by TBBQ exposure suggest the overproduction of ROS, which may account for the increase in the genotoxic stress protein p53. Both upregulation of p53 and reduction of Akt levels inhibited mTOR, which activated autophagy. Addition of 3-MA counteracted the impact of TBBQ on ATG proteins and cell viability. All of these results suggest that TBBQ induces autophagy of RAW 264.7 cells principally by inhibition of the Akt/mTOR signaling pathway, and they implicate ROS in this regulation.

Redox-responsive blend hydrogel films based on carboxymethyl cellulose/chitosan microspheres as dual delivery carrier

A simple method to fabricate redox-responsive composite hydrogel films via incorporating chitosan (CS) microspheres into carboxymethyl cellulose (CMC) hydrogel using a di-sulphide cross-linker cystamine dihydrochloride (CYS) have done in this paper. Dual drugs, an anticancer, 5-Fluorouracil (5-FU) and an antibiotic, Tetracycline Hydrochloride (TH) were used as model drugs. The prepared composite hydrogel films were characterized using FTIR, SEM, rheology measurement, mechanical and swelling tests. Our results showed that the well dispersed spherical CS microspheres endowed hydrogel film increased mechanical properties and swellability. In vitro drug release displayed an accelerated release under weak acidic or reducing media. The in vitro cytotoxicity and cell apoptosis studies showed the drug-loaded composite film caused enhanced inhibition to HepG2 cells in presence of glutathione (GSH). Moreover, the film has exhibited excellent antimicrobial efficacy against E.coli and Staphylococcus aureus. Therefore, our simple and effective dual drug-loaded system has the potential to be used for cancer therapy in the future.

Broadening AIEgen application: rapid and portable sensing of foodstuff hazards in deep-frying oil

We report the first example of an AIEgen probe, QM-TPA, for sensing of triacylglycerol-based polymers in frying oil.