Analysis, occurrence, toxicity and environmental health risks of synthetic phenolic antioxidants: A review

Tert-Butylhydroquinone retards longan fruit deterioration by regulating membrane lipid and energy metabolisms

Longan fruit deteriorates rapidly after harvest, which limits its storability. This study aimed to investigate the effect of tert-butylhydroquinone (TBHQ) on quality maintenance, membrane lipid metabolism, and energy status of longan fruit during 25 °C storage. Compared with control fruit, TBHQ treatment maintained better marketable fruit rate and suppressed activities of phospholipase D (PLD), lipase, and lipoxygenase (LOX), and downregulated expressions of DlPLD, DlLOX, and Dllipase. TBHQ also increased the ratio of unsaturated fatty acids to saturated fatty acids (U/S) and the index of unsaturated fatty acids (IUFA). In addition, higher levels of ATP, ADP, energy charge, NADP+/ NADPH as well as higher activities of H+-ATPase, Ca2+-ATPase and NADK were also observed in TBHQ-treated fruit. These results suggested that TBHQ may maintain postharvest quality of longan fruit by regulating membrane lipid and energy metabolisms.

Dietary supplementation of Cannabis sativa residues in broiler chickens affects performance, carcass characteristics, intestinal morphology, blood biochemistry profile and oxidative stability

Public interest in the cannabis plant has increased after its legalization in many countries. Cannabis sativa residues (CR) are a part of the plant waste in the cannabis industry. The CR contain medicinal properties that could be used as a feed additive in poultry production. The trial was conducted to investigate the effects of CR on growth performance, carcass characteristics, intestinal morphology, and blood biochemistry profile of broiler chickens. In a completely randomized design, 256 one-day-old male Ross 308 broilers were randomly allocated to 4 treatments with 8 replicates and 8 birds per replicate. These 4 dietary treatments included a basal diet with 0, 0.5, 1 and 2% CR for 40 d. The results showed that 2% CR supplementation reduced feed intake (FI) in the starter phase (d 3-23, P < 0.05). The birds in the CR groups had lower FI in the finishing phase (d 24-40, P < 0.01) and the whole raising period (d 3-40, P < 0.01) than the control. However, the body weight and carcass yield were not different (P > 0.05). In addition, the CR diet had no adverse effects on the blood biochemistry profile, including total cholesterol, triglycerides, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total protein, globulin, albumin, and direct bilirubin (P > 0.05). In addition, total bilirubin and malondialdehyde were better in the plasma of CR-supplemented birds than in the control groups (P < 0.05). The observations on intestinal morphology showed that CR supplementation improved the ratio between villus height and crypt depth in the ileum (P < 0.05). In conclusion, CR supplementation can improve intestinal morphology and oxidative stability of broiler chickens. This suggests that CR could potentially be used as an alternative feed additive in broiler production.

Trends in pulse voltammetric techniques applied to foodstuffs analysis: The food additives detection

Food additives are chemical compounds intentionally added during foodstuff production to control technological functions, such as pH, viscosity, stability (color, flavor, taste, and odor), homogeneity, and loss of nutritional value. These compounds are fundamental in inhibition the degradation process and prolonging the shelf life of foodstuffs. However, their inadequate employment or overconsumption can adversely affect consumers' health with the development of allergies, hematological, autoimmune, and reproductive disorders, as well as the development of some types of cancer. Thus, the development and application of simple, fast, low-cost, sensitivity, and selectivity analytical methods for identifying and quantifying food additives from various chemical classes and in different foodstuffs are fundamental to quality control and ensuring food safety. This review presents trends in the detection of food additives in foodstuffs using differential pulse voltammetry and square wave voltammetry, the main pulse voltammetric techniques, indicating the advantages, drawbacks, and applicability in food analysis. Are discussed the importance of adequate choices of working electrode materials in the improvements of analytical results, allowing reliable, accurate, and inexpensive voltammetric methods for detecting these compounds in foodstuffs samples.

Ecological risk of synthetic phenolic antioxidants: A study based on their spatial distribution in water, sediment, and soil from the Yangtze River Delta, China

Environmental occurrence and risks of novel synthetic phenolic antioxidants (SPAs) remain largely unclear. By using a typical algae (Chlorella pyrenoidosa) as model organism, we evaluated the ecological risks of both traditional and novel SPAs, based on their concentrations in water, sediment, and soil collected from the Yangtze River Delta, China. Detection frequencies (DFs) of 10 novel SPAs were 25-100% in water, 3-100% in sediment, and 0-100% in soil, with geometric means (GMs) of 2700 ng/L, 1270 ng/g, and 2440 ng/g, respectively. For 8 traditional SPAs, DFs were 50-100% (GM: 680 ng/L), 3-100% (534 ng/g), and 47-100% (2240 ng/g) in water, sediment, and soil, respectively. AO3114 was the main pollutant in water, while AO1010 dominated in sediment and soil. Notably, low-molecular-weight SPAs showed migration behavior from sediment to water. Four SPAs (AO626, AO1035, AO1098, and AO1076) showed dose- and time-dependent toxicity on Chlorella pyrenoidosa. As time progressed, sediment-released SPAs became more toxic than those in water. Two SPAs (AO1135 and BHT-Q) posed high risks (RQW > 1) to green algae, daphnia, and fish. The SPA mixture exhibited high risks (RQmix > 1) to these organisms, increasing with the trophic level. This research holds valuable guidance for further SPA risk assessments.

Colorimetric/fluorescent dual-mode assay for antioxidant capacity of gallnuts based on CuCo nanozyme and AIE luminogen

In this work, we present a dual-mode assay system consisting of a nanozyme and a luminogen with the aggregation-induced emission (AIE) feature. In the assay system, the chosen nanozyme named CuCo-0 catalyzes the substrate to produce colorimetric signals, while the aggregates of H4ETTC (4,4',4″,4‴-(ethene-1,1,2,2-tetrayl) tetrakis ([1,1'-biphenyl]-4-carboxylic acid), a typical AIE luminogen, generate fluorescent signals. The peroxidase-like activity of the CuCo-0 nanozyme can be remarkably suppressed with sequential additions of antioxidants, leading to a dual-signal response characterized by enhanced fluorescence emission and reduced UV-vis absorbance. On this basis, a dual-mode assay capable of producing both colorimetric and fluorescent signals for the assessment of antioxidant capacity using gallic acid as a representative antioxidant was exploited. Good linearity can be obtained in the 0-60 μM range for both colorimetric analysis and fluorescent analysis, with detection limits of 1.3 μM and 0.35 μM, respectively. Furthermore, this dual-mode assay was successfully applied to real gallnut samples, yielding satisfactory results.

Transforming wastewater treatment: Recent advancements in Catalytic Wet Air Oxidation with pillared clay catalysts for phenol remediation

Catalytic Wet Air Oxidation (CWAO) has recently been recognized as a promising technique for degrading persistent organic pollutants, such as phenol, in wastewater. Among various catalysts, Pillared Interlayer Clays (PILCs) stand out due to their high specific surface area and porous nature. This review delves into the latest progress in CWAO processes utilizing PILCs for the degradation of organic contaminants such as phenol in wastewater. It meticulously assesses the synthesis of PILCs, and their structural properties, including monolithic forms, to understand their effect on catalyst efficiency. Key insights into how these attributes affect the phenol degradation rate and the CWAO process's stability are discussed, providing crucial direction for enhancing catalyst performance. The review highlights the significance of choosing catalysts that offer a balance between cost-efficiency and operational efficacy under mild conditions. The recent results are reported, summarized, and compared, thus proving the feasibility of using PILCs as promising materials for phenol removal. The reaction parameters, phenol conversion, and degradation mechanisms are highlighted. The catalytic efficiency of PILCs was significantly affected by the synthesis methods and reaction parameters, and outperformed most costly catalysts. PILCs are highlighted as especially advantageous catalysts, offering strong performance at lower costs, which boosts the up-scaling opportunities of CWAO methods. This analysis also points out research gaps and proposes directions for future studies, such as exploring innovative PILC synthesis methods to improve their catalytic effectiveness and durability further. It stresses the need to incorporate environmental and sustainability considerations into catalyst design and selection, aligning with the principles of green chemistry in wastewater treatment. Finally, we conclude that proposing new directions for PILCs in CWAO in further naturally-based surface modifications, is also a promising approach for PILCs to perform more efficiently.

Occupational exposure of nail technicians to industrial chemicals: A pilot study

Previous studies have observed the use of complex industrial chemicals in beauty products. However, occupational exposure of beauty practitioners to various chemicals has not been sufficiently assessed. Our study recruited 37 female nail technicians from 28 nail salons in South China and investigated the abundances and profiles of more than 60 industrial chemicals or their metabolites in indoor dust, hand wipes, and urine of nail technicians. Thirty female college students were also recruited for comparison. The results revealed broad exposure of nail technicians to 42 target chemicals or their metabolites, with mono-phthalate esters (mono-PAEs) exhibiting the highest concentrations (median 284 ng/mL), followed by parabens (median 57.9 ng/mL) and antioxidants (median 19.6 ng/mL) in urine. The urinary concentrations of mono-PAEs, parabens, triclosan (TCS) and triclocarban of nail technicians were significantly higher than those of college students. Pre-shift and post-shift urine did not exhibit significant differences for most chemicals, likely reflecting continuous and long-term exposure. Hand wipe levels of TCS and 2,6-di-tert-butyl-4-methylpheno were significantly associated with urinary levels of these chemicals or their metabolites, while such a pattern was not observed between dust and urinary levels. This highlights the influence of dermal contact or hand-to-mouth transfer on the intake of these chemicals. Collectively, our pilot study demonstrates the occupational exposure of nail technicians to industrial chemicals in beauty products and calls for vigilant self-protection measures to mitigate exposure risks in beauty practitioners.

The potential significance of antioxidants in livestock reproduction: Sperm viability and cryopreservation

Male reproductive efficiency is primarily defined by the generation of high-quality and viable sperm cells in farm animals. However, the literature shows that male fertility has declined in recent years due various factors including heat stress, which causes the development of free radicals and reactive oxygen species (ROS) which damages sperm cells. This review aimed to examine the potential significance of antioxidants in increasing and preserving sperm quality and viability. Data used to produce this review paper came from recently published articles in peer reviewed journals. Google Scholar, Science Direct, Research Gate, Web of Science, and the Directory of Open Access Journals were used to access the data. Various studies have shown that antioxidants play acritical role in preserving the sperm quality and viability by protecting sperm cells from the potential damage from oxidative stress induced by the development of oxygen species imbalances. However, there is less information on the use of natural or synthetic antioxidants to preserve semen quality through in vivo procedures, despite its growing popularity and promising results. Hence, there is a need for researchers to explore more on this topic, especially in other livestock species than poultry.

Evaluation of the qualitative properties of the oil extracted from the mixture of Helianthus annuus and Nigella sativa seeds during heating

The oil obtained from black cumin (Nigella sativa) seeds has many health-effective properties, which is used in food applications and in traditional medicine. One practical method to extract its oil is mixing with other seeds such as sunflower (Helianthus anuus) seeds before oil extraction by press. The effectiveness of the cold-press oil obtained from the mixture of black cumin seeds (BS) and sunflower seeds (SF) in different proportions 100:0, 95:5, 90:10, 85:15 and 0:100 (w/w) was studied to evaluate their qualitative properties including peroxide value (PV), acid value, p-anisidine value (AnV), pigments (carotenoid and chlorophyll) content, polyphenols, and profile of fatty acids during heating process (30-150 min at 180 °C). The results revealed that the acid and p-anisidine value of the all samples enhanced with the extension of the heating time, and the peroxide value increased at the beginning of the heating and then decreased with the prolongation of the heating time (p < .05). With the increase of temperature and heating time, the peroxide of sunflower oil increased with a higher slope and speed than that of black seed and blends oil. Changes in the PV and AnV were the fastest in sunflower oil. Blending and heating caused considerable changes in the fatty acid composition of oils, especially myristic, palmitic, and stearic acids. Moreover, the levels of certain unsaturated fatty acids, namely linoleic, oleic, and linolenic acids declined after heating. The carotenoids, chlorophyll and total phenol content decreased gradually during heating treatments. Among extracted oils, SF:BS (15%) had the good potential for stability, with total phenol content of 95.92 (Caffeic acid equivalents/100 g), PV of 2.16 (meq O2/kg), AV of 2.59 (mg KOH/g oil), and AnV of 8.08 after the heating. In conclusion, oil extracted from the mixture of SF and BS can be used as salad and cooking oils with a high content of bioactive components and positive nutritional properties.

Open dumping site as a point source of microplastics and plastic additives: A case study in Thailand

Microplastics (MPs) and plastic additive chemicals are emerging pollutants of great concerns around the world. Open dumping sites can be important sources of those pollutants in emerging countries, but little is known about their occurrence, distribution, transport pathway, and remediation approach. This study aimed to obtain the comprehensive dataset on plastic pollution in an open dumping site in Thailand, including (1) the polymer types and organic/inorganic plastic additives in plastic garbage, (2) horizontal distribution of MPs and plastic additives in the surface soil, (3) the effects of soil-capping treatment, and (4) the vertical transport. First, thirty-two plastic garbage collected from the dumping site were analyzed, and a total of 40 organic chemicals (mean: 1400,000 ng/g dw) and 7 heavy metals (mean: 2,030,000 ng/g dw) were identified. The burdens stored in the dumping site were estimated to reach to 3.3-18 tons for organic additives and 4.9-26 tons for heavy metals. In the surface soil analysis, 13 types of polymers in MPs, 20 elements, and 37 organic plastic additives were detected. The pollution levels were significantly higher near the dumping site than at control sites, indicating that the open dumping site is a point source of MPs and plastic additives. Interestingly, a significantly positive correlation was found between the concentrations of MPs and organic additives in soil. This suggests that MPs act as carriers of plastic-derived chemicals. Soil-capping treatment (including removal of some trash) drastically mitigated the contaminant levels in the surface soil, indicating this treatment is one of the effective approaches to control the horizontal distribution of MPs and plastic additives. However, soil core analyzes implied that the vertical transport is still continued even after soil-capping treatment. Our findings provided the comprehensive dataset to support for understanding plastic pollution in the open dumping site.

Prevalence of synthetic phenolic antioxidants in food contact materials from China and their implications for human dietary exposure through take-away food

The application of disposable tableware has increased substantially in recent times due to the rapidly growing food delivery business in China. Synthetic phenolic antioxidants (SPAs) are widely used in food contact materials (FCMs) to delay the process of oxidation; however, their compositions, concentrations, and potential health hazards remain unclear. Therefore, FCMs comprised of five materials obtained from 19 categories (n = 118) in China were analyzed for SPAs concentrations. FCMs have been found to contain a variety of SPAs, with ∑SPAs concentrations ranging from 44.18 to 69,485.12 μg/kg (median: 2615.63 μg/kg). The predominant congeners identified in the sample include 2,4-di-tert-butylphenol (2,4-DTBP), 2,6-di-tert-butylphenol (2,6-DTBP), and 2,6-di-tert-butyl-p-benzoquinone (BHT-Q) with a median concentration of 885.75, 555.45 and of 217.44 μg/kg, respectively. Milky tea paper cups, instant noodle buckets, milky teacups, and disposable cups showed high levels of SPAs. 2,2'-methylenebis(4-methyl-6-tert-butylphenol) (AO 2246) was predominantly detected in polyethylene and polyethylene terephthalate-based products. The migration test identified disposable plastic cups and bowls as the predominant FCMs and 2,4-DTBP as the dominant SPA. The exposure risk of SPAs decreased with age. In children, the estimated daily intake of ∑SPAs from FCMs was determined to be 17.56 ng/kg body weight/day, which was 8.3 times higher than that of phthalic acid esters. The current findings indicate the potential ingestion risk of SPAs during the daily life application of multiple FCM categories.

An insight into the antioxidant activities and the exploration of record high quantities of quercetin and luteolin in the plant parts of Myxopyrum smilacifolium (wall.) Blume

This study attempts to reveal antioxidants in the plant parts of Myxopyrum smilacifolium (Wall.) Blume using antioxidant assays and LC-MS/MS analysis. Methanol is the most effective solvent for collecting antioxidants. The roots-derived methanol extract demonstrates the greatest antioxidant activity, corresponding to the extremely low IC50 values of 16.39 µg/mL and 19.80 µg/mL for DPPH and ABTS radicals, respectively. The high phenolic and flavonoid contents are the primary reason for outstanding total antioxidant capacity (TAC; i.e. 247.73 ± 1.62 mg GA/g or 163.93 ± 0.83 mg AS/g) of the root extract. LC-MS/MS quantification of five phenolic compounds reveals exceptionally high amounts of quercetin and luteolin in the root extract, ranging from 238.86 ± 5.74 to 310.99 ± 1.44 µg/g and from 201.49 ± 7.84 to 234.10 ± 2.54 µg/g, respectively, in the root-derived methanol extract. The achievement highlights M. smilacifolium as a promising source of natural antioxidants for large-scale medical applications.

Hyaluronic Acid/Ellagic Acid as Materials for Potential Medical Application

The aim of this work was to develop and characterize a thin films composed of hyaluronic acid/ellagic acid for potential medical application. Its principal novelty, distinct from the prior literature in terms of hyaluronic acid films supplemented with phenolic acids, resides in the predominant incorporation of ellagic acid-a distinguished compound-as the primary constituent of the films. Herein, ellagic acid was dissolved in two different solvents, i.e., acetic acid (AcOH) or sodium hydroxide (NaOH), and the surface properties of the resultant films were assessed using atomic force microscopy and contact angle measurements. Additionally, various physicochemical parameters were evaluated including moisture content, antioxidant activity, and release of ellagic acid in phosphate buffered saline. Furthermore, the evaluation of films' biocompatibility was conducted using human epidermal keratinocytes, dermal fibroblasts, and human amelanotic melanoma cells (A375 and G361), and the antimicrobial activity was elucidated accordingly against Staphylococcus aureus ATCC 6538 and Pseudomonas aeruginosa ATCC 15442. Our results showed that the films exhibited prominent antibacterial properties particularly against Staphylococcus aureus, with the 80HA/20EA/AcOH film indicating the strong biocidal activity against this strain leading to a significant reduction in viable cells. Comparatively, the 50HA/50EA/AcOH film also displayed biocidal activity against Staphylococcus aureus. This experimental approach could be a promising technique for future applications in regenerative dermatology or novel strategies in terms of bioengineering.

Ubiquity of Synthetic Phenolic Antioxidants in Children's Cerebrospinal Fluid from South China: First Evidence for Their Penetration across the Blood-Cerebrospinal Fluid Barrier

Synthetic phenolic antioxidants (SPAs) and relevant transformation products (TPs) are potentially neurotoxic pollutants to which humans are widely exposed. However, their penetration behavior across the brain barrier and associated exposure to the central nervous system (CNS) remain unknown. This study is the first to investigate a wide range of 30 SPAs and TPs, including emerging SPAs, in matched serum and cerebrospinal fluid (CSF) samples from children in Guangzhou, China. Sixty-two children of either sex aged <14 years with nonbloody CSF and complete clinical information were included. The findings demonstrated the ubiquitous occurrence of many SPAs and TPs, particularly BHT, 2,4-di-tert-butylphenol (DBP), AO 1010, AO 1076, BHT-Q, and BHT-quinol, not only in serum but also in the CSF. Median total concentrations of SPAs and TPs were up to 22.0 and 2.63 ng/mL in serum and 14.5 and 2.11 ng/mL in CSF, respectively. On calculating the penetration efficiencies across the blood-CSF barrier (BCSFB) (RCSF/serum, CCSF/Cserum) for selected SPAs and TPs, their RCSF/serum values (median 0.52-1.41) were highly related to their physicochemical properties, indicating that passive diffusion may be the potential mechanism of BCSFB penetration. In addition, the RCSF/serum values were positively correlated with the barrier permeability index RAlb (AlbuminCSF/Albuminserum), indicating that barrier integrity is an important determinant of BCSFB penetration. Overall, these results will improve our perception of human internal exposure to SPAs and lay a solid foundation for assessing the risk of CNS exposure to various SPAs.

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.

Thermal decomposition characteristics of BHT and its peroxide (BHTOOH)

2,6-Di-tert-butyl-4-methylphenol (BHT) is an excellent antioxidant that is easily oxidized to 2,6-di-tert-butyl-4-hydroperoxyl-4-methyl-2,5-cyclohexadienone (BHTOOH). For the safety of BHT production and usage, it is meaningful to study the thermal stability and decomposition properties of BHT and BHTOOH. In this paper, the thermal decomposition properties of BHT and BHTOOH were compared by the mini closed pressure vessel test (MCPVT) and differential scanning calorimetry (DSC). Their kinetics of thermal decomposition were studied using thermogravimetric analysis (TGA). The thermal decomposition products of BHT and BHTOOH were analyzed by gas chromatography-mass spectrometry (GC-MS). The results show that there was no significant change in temperature pressure when BHT was warmed up under a nitrogen atmosphere, indicating that BHT was stable within 400 K. The thermal decomposition reaction of BHTOOH was rapid with an initial reaction temperature of 375.2 K. The initial exothermic temperature (Ti) and heat release (QDSC) of DSC were 384.9 K and 865.0 J g-1, respectively. The apparent activation energies (Ea) for the thermal decomposition reactions of BHT and BHTOOH calculated by the Kissinger method were 151.8 kJ mol-1 and 66.07 kJ mol-1, respectively. The main decomposition products of BHT were isobutene and 2-tert-butyl-4-methylphenol. The thermal decomposition products of BHTOOH included BHT, 2,6-di-tert-butyl-4-ethylphenol, 3,5-di-tert-butyl-4-hydroxybenzaldehyde, 4,4'-(1,2-ethanediyl) bis [2,6-bis (1,1-dimethylethyl) phenol, etc. Based on the thermal decomposition behavior and products, the reaction pathway has been described. These results indicate that BHT is a potential thermal hazard during production, storage and application. For the safety of the chemical industry, the oxidation of BHT should be avoided.

Copper-crosslinked carbon dot hydrogel nanozyme for colorimetric - tert-butylhydroquinone biosensing and smartphone-assisted visual ratiometric assay

Due to the potential environment and health risks of tert-butylhydroquinone (TBHQ), rapid, portable, selective and sensitive quantification of TBHQ in food and the environment are strictly essential. With this in mind, a selective, sensitive and rapid colorimetric TBHQ biosensor was developed using rationally designed copper-crosslinked carbon dot hydrogel nanozyme (BC-CDs@Cu). The BC-CDs@Cu had a high peroxidase-like activity toward the chromogenic reaction of hydrogen peroxide with dopamine via the generation of hydroxyl radicals and electron transfer process. The Michaelis-Menten constants of BC-CDs@Cu for dopamine and hydrogen peroxide were determined to be 0.86 and 0.91 mM. The added TBHQ markedly inhibited the BC-CDs@Cu-catalyzed dopamine oxidation by hydrogen peroxide, ascribing to the highly effective and rapid scavenging of hydroxyl radicals and the suppression of electron transfer. The inhibitory extent was applied for well quantifying TBHQ in the range of 0.5 - 20.0 μM with a detection limit of 70 nM. The proposed biosensor had a negligible response to various interfering substances. Moreover, a smartphone-assisted visual ratiometric biosensor was fabricated, and used to accomplish portable quantification of TBHQ in edible oils and water samples. This work reveals the enormous potential of hydrogel nanozyme, which will open a new situation for the detection of hazardous substances.

Assessing developmental neurotoxicity of emerging environmental chemicals using multiple in vitro models: A comparative analysis

Newly synthesized chemicals are being introduced into the environment without undergoing proper toxicological evaluation, particularly in terms of their effects on the vulnerable neurodevelopment. Thus, it is important to carefully assess the developmental neurotoxicity of these novel environmental contaminants using methods that are closely relevant to human physiology. This study comparatively evaluated the potential developmental neurotoxicity of 19 prevalent environmental chemicals including neonicotinoids (NEOs), organophosphate esters (OPEs), and synthetic phenolic antioxidants (SPAs) at environment-relevant doses (100 nM and 1 μM), using three commonly employed in vitro neurotoxicity models: human neural stem cells (NSCs), as well as the SK-N-SH and PC12 cell lines. Our results showed that NSCs were more sensitive than SK-N-SH and PC12 cell lines. Among all the chemicals tested, the two NEOs imidaclothiz (IMZ) and cycloxaprid (CYC), as well as the OPE tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), generated the most noticeable perturbation by impairing NSC maintenance and neuronal differentiation, as well as promoting the epithelial-mesenchymal transition process, likely via activating NF-κB signaling. Our data indicate that novel NEOs and OPEs, particularly IMZ, CYC, and TDCIPP, may not be safe alternatives as they can affect NSC maintenance and differentiation, potentially leading to neural tube defects and neuronal differentiation dysplasia in fetuses.

Progress in Understanding Oxidative Stress, Aging, and Aging-Related Diseases

Under normal physiological conditions, reactive oxygen species (ROS) are produced through redox reactions as byproducts of respiratory and metabolic activities. However, due to various endogenous and exogenous factors, the body may produce excessive ROS, which leads to oxidative stress (OS). Numerous studies have shown that OS causes a variety of pathological changes in cells, including mitochondrial dysfunction, DNA damage, telomere shortening, lipid peroxidation, and protein oxidative modification, all of which can trigger apoptosis and senescence. OS also induces a variety of aging-related diseases, such as retinal disease, neurodegenerative disease, osteoarthritis, cardiovascular diseases, cancer, ovarian disease, and prostate disease. In this review, we aim to introduce the multiple internal and external triggers that mediate ROS levels in rodents and humans as well as the relationship between OS, aging, and aging-related diseases. Finally, we present a statistical analysis of effective antioxidant measures currently being developed and applied in the field of aging research.

Exposure to environmental levels of 2,4-di-tert-butylphenol affects digestive glands and induces inflammation in Asian Clam (Corbicula fluminea)

2,4-Di-tert-butylphenol (2,4-DTBP) is used as an antioxidant added to plastics. Due to its potential toxicity and relatively high concentrations in environments and presence in human tissue, concern has been raised for 2,4-DTBP as a contaminant associated with adverse health outcomes. However, studies on the toxicity of 2,4-DTBP are relatively limited, especially for benthic aquatic organisms. In this study, Asian clams (Corbicula fluminea) were exposed to environmentally relevant concentrations of 2,4-DTBP (0.01-1 μM, corresponding to 2.06-206.32 μg/L) for 21 days. Accumulation of 2,4-DTBP was noted in both gills and digestive glands, with the latter presenting as the primary target tissue. Increased damage rate of digestive tube and cellular DNA damage were observed in the digestive glands of 2,4-DTBP exposed clams. The injury was attributed to the imbalance of the antioxidant system, characterized by elevated oxidative stress and inflammation (upregulation of ROS, MDA, NO, and pro-inflammatory factors). In contrast, upon 2,4-DTBP exposure, antioxidant system in gills was activated, while ROS and NO were not promoted. Moreover, NF-κB and IL-1 were significantly decreased. These results suggested that biochemical mechanisms were activated in gills to maintain homeostasis. Internal exposure in the digestive gland was significantly correlated with the biochemical biomarkers tested, underscoring the potential risk associated with the bioaccumulation of 2,4-DTBP from contaminated environments. These findings provide novel insights into toxicity of 2,4-DTBP in bivalves, contributing valuable knowledge to risk assessment and chemical management.

Kappaphycus alvarezii as a renewable source of kappa-carrageenan and other cosmetic ingredients

Kappa-carrageenan is one of the most traded marine-derived hydrocolloids used in the food-and-beverage, pharmaceuticals, and personal care/cosmetics industries. K. alvarezii (previously known as Kappaphycus alvarezii) is arguably the most important natural producer based on annual production size and near-homogeneity of the product (i.e., primarily being the kappa-type). The anticipated expansion of the kappa-carrageenan market in the coming years could easily generate >100,000 MT of residual K. alvarezii biomass per year, which, if left untreated, can severely affect the environment and economy of the surrounding area. Among several possible valorization routes, turning the biomass residue into anti-photoaging cosmetic ingredients could potentially be the most sustainable one. Not only optimizing the profit (thus better ensuring economic sustainability) relative to the biofuels- and animal feed-routes, the action could also promote environmental sustainability. It could reduce the dependency of the current cosmetic industry on both petrochemicals and terrestrial plant-derived bioactive compounds. Note how, in contrast to terrestrial agriculture, industrial cultivation of seaweeds does not require arable land, freshwater, fertilizers, and pesticides. The valorization mode could also facilitate the sequestration of more greenhouse gas CO2 as daily-used chemicals, since the aerial productivity of seaweeds is much higher than that of terrestrial plants. This review first summarizes any scientific evidence that K. alvarezii extracts possess anti-photoaging properties. Next, realizing that conventional extraction methods may prevent the use of such extracts in cosmetic formulations, this review discusses the feasibility of obtaining various K. alvarezii compounds using green methods. Lastly, a perspective on several potential challenges to the proposed valorization scheme, as well as the potential solutions, is offered.

Effect of type and concentration of antioxidant on sperm motility, viability, and DNA integrity of climbing perch Anabas testudineus Bloch, 1792 (Pisces: Anabantidae) post-cryopreservation

Sperm quality is preserved through the crucial involvement of antioxidants, which play a vital role in minimizing the occurrence of reactive oxygen species (ROS) during the cryopreservation process. The suitability of the type and concentration of antioxidants are species-dependent, and this study is crucial in order to improve the quality of the climbing perch sperm post-cryopreservation. Therefore, this study aimed to determine the best type and concentration of antioxidants for cryopreservation of climbing perch Anabas testudineus sperm. To achieve this, 6 types of antioxidants, namely, ascorbic acid, beta-carotene, glutathione, butylated hydroxytoluene (BHT), myo-inositol, and alpha-tocopherol, with inclusion of a control were tested in 3 replications at three concentration levels of 0 mg/L (control), 20 mg/L, 40 mg/L, and 60 mg/L. Sperm was diluted in a glucose-base extender at a ratio of 1:60 (sperm: glucose base), then 10 % DMSO and 5 % egg yolk was added before cryopreservation for two weeks. The results showed that the type and concentration of antioxidants had a significant effect on the motility and viability of cryopreserved climbing perch sperm (P < 0.05), where the best results for ascorbic acid, beta-carotene, glutathione, myo-inositol, and alpha-tocopherol were obtained at a concentration of 60 mg/L, while BHT was at a concentration of 20 mg/L. The best results for glutathione, myo-inositol, and alpha-tocopherol were significantly different from other treatments, while the best results for ascorbic acid and beta-carotene (60 mg/L) were not significantly different from the 40 mg/L concentration, while the best results for BHT were not significantly different from the control treatments. Therefore, the best concentration of glutathione, myo-inositol, and alpha-tocopherol was 60 mg/L, while for ascorbic acid and beta-carotene it was 40 mg/L, and BHT was not recommended. DNA integrity analysis indicated the absence of fragmentation in all samples, including fresh, control, and treated sperm. Based on practical and economic considerations, myo-inositol at 60 mg/L was recommended for cryopreservation of climbing perch A. testudineus sperm.

The impact of natural spices additions on hazards development and quality control in roast beef patties

The current focus in thermally processed meat production is to reduce the presence of hazardous compounds while maintaining product quality. This study utilized UPLC-MS/MS to examine the effects of rosemary, turmeric, and bay leaf on the development of hazards in roast beef patties, which demonstrated simultaneous inhibitory effects on malondialdehyde, glyoxal, methylglyoxal, 12 heterocyclic aromatic amines, acrylamide, and 5-hydroxymethylfurfural. Correlation analysis revealed that the total phenolic content and ferric-reducing antioxidant power of the spices were negatively correlated with polar hazards, non-polar heterocyclic aromatic amines, and aldehyde hazards, respectively. These findings underscore the vital role of hydroxyl groups and aromatic rings of phenols in inhibiting hazards formation. Additionally, the application of spices significantly reduced cooking loss and water loss and positively influenced textural quality and amino acid retention. These findings contribute to the understanding of the inhibitory effects of spices on multiple hazards and the quality control of heat-processed meat products.

Biomass - metal oxide nano composite for the decontamination of phenol from polluted environment - parametric, kinetics and isotherm studies

The contamination of aqueous environment by phenol poses a major threat due to its hyper toxic effects and removal of phenol is challenging due to its hydrophilic properties. This research study examines the surface encapsulation of iron oxide (IO) with bio-derived carbon-based date palm (DP) to make date palm-iron oxide (DP-IO) nanocomposite to potentially remediate phenol in aqueous environment. Phenol removal percentage is predominantly influenced by environmental factors, namely pH, nano sorbent loading, temperature, agitation speed, and initial phenol concentration. Under optimum conditions of 30 °C and pH 7.8, 80.30% of phenol was removed using a 0.75 g/L sorbent load with 100 mg/L initial phenol concentration. Langmuir isotherm fitted well (R2 > 0.997), supporting single-layer phenol attachment with maximum bio-sorption capacity of 72.46 mg/g. A pseudo-2nd-order (PSO) kinetic model is identified to be the most appropriate for the DP-IO sorption experiment (R2>0.999). Scanning electron microscopic images, X-ray diffraction observations, FT-IR plots, and thermogravimetric analysis have been used to characterize. The removal mechanism involves unimolecular layer and chemisorption is identified as a rate determining step. The reuse potential proved that the synthesized nanocomposite as a sustainable solution for phenolic wastewater treatment.

Synthetic Antioxidants as Contaminants of Emerging Concern in Indoor Environments: Knowns and Unknowns

Synthetic antioxidants, including synthetic phenolic antioxidants (SPAs), amine antioxidants (AAs), and organophosphite antioxidants (OPAs), are essential additives for preventing oxidative aging in various industrial and consumer products. Increasing attention has been paid to the environmental contamination caused by these chemicals, but our understanding of synthetic antioxidants is generally limited compared to other emerging contaminants such as plasticizers and flame retardants. Many people spend a significant portion (normally greater than 80%) of their time indoors, meaning that they experience widespread and persistent exposure to indoor contaminants. Thus, this Perspective focuses on the problem of synthetic antioxidants as indoor environmental contaminants. The wide application of antioxidants in commercial products and their demonstrated toxicity make them an important family of indoor contaminants of emerging concern. However, significant knowledge gaps still need to be bridged: novel synthetic antioxidants and their related transformation products need to be identified in indoor environments, different dust sampling strategies should be employed to evaluate human exposure to these contaminants, geographic scope and sampling scope of research on indoor contamination should be broadened, and the partition coefficients of synthetic antioxidants among different media need to be investigated.

Applications of Plant Bioactive Compounds as Replacers of Synthetic Additives in the Food Industry

According to the Codex Alimentarius, a food additive is any substance that is incorporated into a food solely for technological or organoleptic purposes during the production of that food. Food additives can be of synthetic or natural origin. Several scientific evidence (in vitro studies and epidemiological studies like the controversial Southampton study published in 2007) have pointed out that several synthetic additives may lead to health issues for consumers. In that sense, the actual consumer searches for "Clean Label" foods with ingredient lists clean of coded additives, which are rejected by the actual consumer, highlighting the need to distinguish synthetic and natural codded additives from the ingredient lists. However, this natural approach must focus on an integrated vision of the replacement of chemical substances from the food ingredients, food contact materials (packaging), and their application on the final product. Hence, natural plant alternatives are hereby presented, analyzing their potential success in replacing common synthetic emulsifiers, colorants, flavorings, inhibitors of quality-degrading enzymes, antimicrobials, and antioxidants. In addition, the need for a complete absence of chemical additive migration to the food is approached through the use of plant-origin bioactive compounds (e.g., plant essential oils) incorporated in active packaging.

Occurrence and distribution of PPCPs in water from two largest urban lakes of China: First perspective from DGT in-situ measurement

Pharmaceutical and personal care products (PPCPs) are an important group of emerging contaminants that may threaten organisms at trace concentrations. However, research on the occurrence of PPCPs in urban lakes in China is still scarce. In this study, 15 PPCPs in the Tangxun Lake and the Donghu Lake were collected using the diffusive gradients in thin-films (DGT) technique and analyzed by high performance liquid chromatography tandem-mass spectrometry (HPLC-MS/MS). Thirteen of the 15 targeted PPCPs were detected in the Tangxun Lake, and all PPCPs were detected in the Donghu Lake, with total concentrations ranging from 160 to 730 ng/L (average: 401 ng/L) and 187 to 1933 ng/L (average: 653 ng/L), respectively. Bisphenol A (BPA) was the dominant PPCP, followed by disinfectants in both lakes. The total concentrations of PPCPs in the Donghu Lake were higher than those in the Tangxun Lake. The spatial distribution characteristics of PPCPs in the two lakes were different, with higher total concentrations in the eastern part than in the western part of the Tangxun Lake spatially and higher in the north-western part than in the south-eastern part of the Donghu Lake. The results of the risk assessment showed that BPA and estrone posed high risks to the aquatic environment (RQ ≥ 1), while triclosan and estriol presented a medium risk (0.1 ≤ RQ < 1) in some sites. This study was the first attempt to apply DGT for providing vital data on the evaluation of the ecological risk of PPCPs in the two largest lakes in China, and attention should be paid to the long-term ecological effects caused by the occurrence of PPCPs in lakes.

Development of a simplified human embryonic stem cell-based retinal pre-organoid model for toxicity evaluations of common pollutants

OBJECTIVE

To explore the retinal toxicity of pharmaceuticals and personal care products (PPCPs), flame retardants, bisphenols, phthalates, and polycyclic aromatic hydrocarbons (PAHs) on human retinal progenitor cells (RPCs) and retinal pigment epithelial (RPE) cells, which are the primary cell types at the early stages of retinal development, vital for subsequent functional cell type differentiation, and closely related to retinal diseases.

MATERIALS AND METHODS

After 23 days of differentiation, human embryonic stem cell (hESC)-based retinal pre-organoids, containing RPCs and RPE cells, were exposed to 10, 100, and 1000 nM pesticides (butachlor, terbutryn, imidacloprid, deltamethrin, pendimethalin, and carbaryl), flame retardants (PFOS, TBBPA, DBDPE, and TDCIPP), PPCPs (climbazole and BHT), and other typical pollutants (phenanthrene, DCHP, and BPA) for seven days. Then, mRNA expression changes were monitored and compared.

RESULTS

(1) The selected pollutants did not show strong effects at environmental and human-relevant concentrations, although the effects of flame retardants were more potent than those of other categories of chemicals. Surprisingly, some pollutants with distinct structures showed similar adverse effects. (2) Exposure to pollutants induced different degrees of cell detachment, probably due to alterations in extracellular matrix and/or cell adhesion.

CONCLUSIONS

In this study, we established a retinal pre-organoid model suitable for evaluating multiple pollutants' effects, and pointed out the potential retinal toxicity of flame retardants, among other pollutants. Nevertheless, the potential mechanisms of toxicity and the effects on cell detachment are still unclear and deserve further exploration. Additionally, this model holds promise for screening interventions aimed at mitigating the detrimental effects of these pollutants.

Developmental and neurobehavioral toxicity of 2,2'-methylenebis(6-tert-butyl-4-methylphenol) (antioxidant AO2246) during the early life stage of zebrafish

BACKGROUND

2,2'-Methylenebis (4-methyl-6-tert-butylphenol) (AO2246) is a synthetic phenolic antioxidant extensively used in food packaging bags and cosmetics. Recently, AO2246 was detected with unexpectedly high concentrations in plasma and breast milk samples from pregnant and lactating women. Hence, it is essential to conduct a thorough investigation to evaluate the detrimental effects of AO2246 on biota.

OBJECTIVE

To investigate the developmental and behavioral toxicity of AO2246 in zebrafish, as well as the molecular mechanisms underlying these effects.

METHODS

Zebrafish embryos were exposed to AO2246 at concentrations ranging from 0.05 to 10 μM for up to 6 days postfertilization (dpf). Hatching rate, survival rate, heart rate, and body length were measured. Locomotor behavioral and electrophysiologal analyses were performed. Two fluorescence-labeled transgenic zebrafish lines (endothelium-Tg and macrophage/microglia-Tg) were employed. RNA sequencing was carried out.

RESULTS

AO2246 has a 96-hour LC50 value of 3 μM. The exposure of AO2246 resulted in a significant reduction in both hatching rate and heart rate. Analysis of locomotor behavior demonstrated that larvae exposed to AO2246 doses exceeding 2 μM exhibited a significant decrease in both total distance and mean velocity. Electrophysiological recordings demonstrated a noteworthy reduction in spike activity at a concentration of 3 μM, relative to control conditions. The administration of AO2246 at 3 μM elicited morphological reactivity and immune alteration of the midbrain microglia in the macrophage/microglia-transgenic zebrafish line, indicating a potential contribution of neurological disorders to behavioral defects. RNA sequencing analysis revealed altered gene expression profiles at high AO2246 concentrations, particularly the dysregulation of pathways associated with neuronal function.

CONCLUSIONS

The present study demonstrates that AO2246 exposure elicits developmental and neurobehavioral toxicity in zebrafish larvae. Specifically, exposure to AO2246 was found to cause disturbances in neuronal electrophysiological activity and neurological disorders, which ultimately led to the impairment of locomotor behavior in zebrafish larvae.

Natural antioxidants as strategy to minimize the presence of lipid oxidation products in canned fish: Research progress, current trends and future perspectives

Canned fish is one of the most popular forms of fish consumption due to its high nutritional value, availability, and practicality. However, canning may induce lipid oxidation. Thus, this study provides in-depth information on the impact of high temperatures applied during canning on fish lipids. The thermo-oxidation is evidenced, for example, by the high levels of both primary and secondary oxidation products determined in fish after canning, as well as the presence of harmful compounds such as cholesterol oxides. Given the role of lipid oxidation in canned fish, this study also presents a comprehensive review on using natural antioxidants to control it. The antioxidant properties of common liquid mediums (vegetable oils and sauces) are highlighted. Moreover, adding algae extracts, spices, and condiments to the liquid medium to enhance its antioxidant potential has been considered, while the exploitation of by-products and wastes from the food industry also emerges as a suitable strategy. Besides the promising results, these practices may promote positive impacts on other quality parameters (e.g. water and oil holding capacities, texture, microbiological growth). However, further studies are needed, including research on aspects related to safety, effective concentrations and application methods, without ignoring consumers' sensory acceptance.

The key constituents underlying the combined toxicity of eight cosmetic contaminants towards Vibrio qinghaiensis

Cosmetic additives (ADDs) and packaging plasticizers (PLAs) probably present potential risks and dangers to the environment and human body as emerging pollutants. To investigate their potential risks and dangers, five ADDs including methyl paraben (MET), ethyl paraben (ETH), propyl paraben (PRO), butyl-hydroxy anisole (BHA), and salicylic acid (SAL), as well as three PLAs including bisphenol A (BPA), bisphenol S (BPS) and tris(2-butoxyethyl) phosphate (TBEP) were selected as research objects, and ten mixture rays (R1-R10) composed of the eight components were designed by the uniform design ray (UD-Ray) method. The toxicities of the eight cosmetic pollutants and their eight-component mixture system towards Vibrio qinghaiensis sp.-Q67 (Q67) were systematically determined by the time-dependent microplate toxicity analysis (t-MTA) method. The three-dimensional (3D) surface of deviation from the concentration addition model (dCA) was utilized to qualitatively and quantitatively analyse the toxicity interaction of the mixtures and the correlation between toxicity interaction and the components' concentration ratios. Finally, eight individual pollutants and representative rays with significant inhibitory and interactive effects were selected to analyse DNA and soluble proteolysis as well as the microstructure and morphology of Q67 after treatment with single chemicals and their mixtures. The results showed that the eight cosmetic pollutants had conspicuous concentration-dependent toxicity and acute toxicity, and none of them, except BPS, BPA and ETH, had time-dependent toxicity. All rays had time/concentration-dependent toxicity and acute toxicity. At the same time, the toxicity interaction of these mixture rays was predominantly antagonism and the strongest antagonism appeared at high concentrations at 12 h. Nevertheless, the components' concentration ratio (pi) was the decisive factor for the type of mixture interaction. The correlation analysis revealed a significant positive linear correlation between mixture toxicity and pETH and pBPA, which indicated that ETH and BPA were the key components of the toxic effects. However, there was a significant negative linear correlation between the antagonism intensity and pBPA and pTBEP, which demonstrated that BPA and TBEP were the key components of the antagonism intensity. Pollutants and their mixtures can also damage cellular structures, and mixtures can exacerbate the dissolution of DNA and soluble proteins.

Optimization of antioxidant and lycopene extraction from tomato pomace using Hansen solubility parameters and its application in chicken meat preservation

Tomato pomace, composed of peels and seeds, is often discarded or used as animal feed. However, it contains valuable phytochemicals, including lycopene. Lycopene, a natural pigment, is an antioxidant known for reducing the risk of chronic diseases like cardiovascular ailments and cancer. In this study, we aimed to study the possibility of valorizing tomato pomace by quantifying phenolic compounds, evaluating the antioxidant activity of their extracts, as well as extracting and quantifying lycopene, and studying the effect of tomato peel extract on the oxidative stability of chicken patties during storage. The effectiveness of different solvent mixtures for the extraction of lycopene was evaluated using Hansen solubility parameters (HSPs). The obtained results showed that the best solvent mixture was hexane/acetone (50/50) with a Hansen theoretical distance of 7.2, indicating its favorable solvation power. It also achieved a notable extraction yield of 3.12% and the highest lycopene yield of 20.05 mg/100 g. This combination demonstrated the highest values in terms of total phenolic (24.06 mg equivalent gallic acid/100 g dry matter) and flavonoid content (30.55 mg equivalent catechin/100 g dry matter), indicating a significant presence of these compounds. However, its 1,1-diphenyl-2-picrylhydrazyl (13.51 µg/mL) and ABTS, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid, (8.52 µg/mL) IC50 values were comparatively lower than the other mixes. The use of this fraction as a food additive and antioxidant showed significant competitiveness with the conventional preservative, 2,6-di-tert-butyl-4-methylphenol. Tomato extract can be considered a potential natural preservative in food preparations due to its high lycopene content. PRACTICAL APPLICATION: This research provides valuable insights into optimizing the extraction of antioxidants from tomato pomace, using HSPs. The findings have the potential to benefit the food industry by developing improved methods for preserving chicken meat through the application of these optimized antioxidant extracts. By enhancing the preservation process, this study may contribute to extending the shelf life and maintaining the quality of chicken meat, leading to reduced food waste and improved consumer satisfaction.

Boric acid group-functional Tb-MOF as a fluorescent and captured probe for the highly sensitive and selective determination of propyl gallate in edible oils

This study reports the development of a Tb-metal-organic framework (Tb-MOF)-based fluorescent platform for the detection of propyl gallate (PG). The Tb-MOF using 5-boronoisophthalic acid (5-bop) as the ligand exhibited multiple emissions at 490, 543, 585, and 622 nm under an excitation wavelength of 256 nm. The fluorescence of Tb-MOF was selectively and significantly weakened in the presence of PG due to the special nucleophilic reaction between the boric acid of Tb-MOF and o-diphenol hydroxyl of PG, and the combined effect of static quenching and internal filtering. Furthermore, this sensor enabled the determination of PG within seconds in a wide linear range of 1-150 μg/mL, and with a low detection limit of 0.098 μg/mL, and high specificity against other phenolic antioxidants. This work provided a new route for the sensitive and selective determination of PG in soybean oil, thus was perspective to monitor and reduce the risk of PG overuse.

Synthetic phenolic antioxidants evoked hepatoxicity in grass carp (Ctenopharyngodon idella) through modulating the ROS-PI3K/mTOR/AKT pathway: Apoptosis-autophagy crosstalk

Synthetic phenolic antioxidants (SPAs) are an environmental concern due to their persistence nature and bioaccumulation. However, the hepatoxicity and mechanisms of SPAs in aquatic organisms remain poorly understood. In this study, grass carp were exposed to two representative SPAs (BHA and BHT) at environmentally relevant levels (0.1 μM) for 30 days. We observed that BHA and BHT exposure significantly increased the levels of serum aminotransferase (ALT) and aspartate aminotransferase (AST) in grass carp, accompanied by mild inflammatory cell infiltration and irregularity in the shape of hepatocytes. Dihydro ethylenediamine staining showed that BHA and BHT exposure resulted in elevated levels of superoxide levels, accompanied by increased antioxidant enzyme activities (T-AOC, SOD, CAT, GSH-PX) and MDA levels, which is suggestive of oxidative stress responses in the liver of grass carp. Besides, BHA and BHT could dock into the pocket of phosphatidylinositol 3-kinases (PI3K) and thereby inhibiting PI3K/mammalian target of rapamycin (mTOR)/protein kinase B (AKT) signaling cascades. Meanwhile, our results clarified that BHA and BHT could promote autophagosome production and increase the expression of key autophagy proteins, likely due to inhibition of PI3K/mTOR/AKT signaling pathway. Moreover, BHA and BHT could induce apoptotic process by upregulating the expression of Bax, Caspase3 and Caspase8 and downregulating Bcl2 expression. Notably, BHT exhibited more hepatoxicity on the indicators of the apoptosis and oxidative stress than BHA. In summary, our findings demonstrated that BHA and BHT exposure could induce liver damage induced via regulating ROS/PI3K-mediated autophagic hyperactivation, which is a crucial step in triggering hepatocyte death. This study provides novel insight into the potential mechanisms underlying liver damage caused by BHA and BHT in aquatic organisms, and offers a new theoretical basis for ecological risk assessment of SPAs.

Using plant-based compounds as preservatives for meat products: A review

The susceptibility of meat and meat products (MP) to oxidation and microbial deterioration poses a risk to the nutritional quality, safety, and shelf life of the product. This analysis provides a brief overview of how bioactive compounds (BC) impact meat and MP preservation, and how they can be utilized for preservation purposes. The use of BC, particularly plant-based antioxidants, can reduce the rate of auto-oxidation and microbial growth, thereby extending the shelf life of MP. These BC include polyphenols, flavonoids, tannins, terpenes, alkaloids, saponins, and coumarins, which have antioxidant and antimicrobial properties. Bioactive compounds can act as preservatives and improve the sensory and physicochemical properties of MP when added under appropriate conditions and concentrations. However, the inappropriate extraction, concentration, or addition of BC can also lead to undesired effects. Nonetheless, BC have not been associated with chronic-degenerative diseases and are considered safe for human consumption. MP auto-oxidation leads to the generation of reactive oxygen species, biogenic amines, malonaldehyde (MDA), and metmyoglobin oxidation products, which are detrimental to human health. The addition of BC at a concentration ranging from 0.025 to 2.5% (w/w in powdered or v/w in oil or liquid extracts) can act as a preservative, improving color, texture, and shelf life. The combination of BC with other techniques, such as encapsulation and the use of intelligent films, can further extend the shelf life of MP. In the future, it will be necessary to examine the phytochemical profile of plants that have been used in traditional medicine and cooking for generations to determine their feasibility in MP preservation.

Synthetic Phenolic Antioxidants and Their Metabolites in Follicular Fluid and Association with Diminished Ovarian Reserve: A Case-Control Study

BACKGROUND

Diminished/decreased ovarian reserve (DOR) is a disorder of ovarian function, which severely affects women's reproductive health. Accumulating evidence has found that adverse environmental factors can affect ovarian function. However, whether synthetic phenolic antioxidants (SPAs) exposure is associated with DOR is still unknown.

OBJECTIVES

We explored whether concentrations of SPAs and their metabolites are associated with DOR.

METHODS

A case-control study was conducted from January 2019 to January 2020 in China. One hundred eighty-one women 20-44 years of age, with (case group, n=63) and without DOR (control group, n=118) were included in our study. The follicular fluid concentrations of typical SPAs and their metabolites were measured, including butylated hydroxyanisole (BHA), tert-butylhydroquinone (TBHQ), butylated hydroxytoluene (BHT), and five BHT metabolites [3,5-di-tert-butyl-4-hydroxy-benzylalcohol (BHT-OH), 3,5-di-tert-butyl-4-hydroxybenzaldehyde (BHT-CHO), 3,5-di-tert-butyl-4-hydroxybenzoic acid (BHT-COOH), 2,6-di-tert-butyl-1,4-benzoquinone (BHT-Q), and 2,6-di-tert-butyl-4-hydroxy-4-methylcyclohexa-2,5-dien-1-one (BHT-quinol)]. Information about serum basal concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), and anti-Müllerian hormone (AMH) and the basal antral follicle count (AFC) was collected.

RESULTS

The measured frequencies of BHA, TBHQ, BHT, BHT-OH, BHT-CHO, BHT-COOH, BHT-Q, and BHT-quinol in follicular fluid were 1.7%, 2.2%, 40.3%, 46.4%, 57.5%, 100%, 64.6%, and 49.2%, respectively. The concentrations of BHT-CHO (0.49 ng/mL vs. 0.12 ng/mL, p=0.041), BHT-COOH (0.45 ng/mL vs. 0.28 ng/mL, p<0.001), BHT-Q (0.70 ng/mL vs. 0.13 ng/mL, p<0.001), and the sum of five BHT metabolites (Σ5metabolites; 1.79 ng/mL vs. 1.0 ng/mL, p<0.001) in the case group were significantly higher than those in the control group. The risk of DOR was further analyzed according to the tertiles of chemical concentration. Compared with the low levels of BHT metabolites, the adjusted odds ratios (ORs) for DOR were significantly increased in the high levels of BHT-CHO [OR=3.19, 95% confidence interval (CI): 1.22, 8.31, p=0.018], BHT-COOH [OR=4.73 (95% CI: 1.63, 13.71), p=0.004], and BHT-Q [OR=4.48 (95% CI: 1.69, 11.86), p=0.003] after adjusting for age, body mass index, education, infertility type, triglycerides, and total cholesterol. Moreover, compared with the low level of Σ5metabolites, increased adjusted ORs for DOR were found both in the middle level [OR=4.11 (95% CI: 1.44, 11.75), p=0.008] and high level [OR=5.51 (95% CI: 1.81, 16.77), p=0.003], showing an obvious dose-response relationship (pTrend=0.003).

CONCLUSION

In this study, we report the measured frequency and concentrations of BHA, TBHQ, BHT, and their metabolites in follicular fluid. Moreover, we found the concentrations of BHT metabolites, especially BHT-CHO, BHT-COOH, and BHT-Q, are positively associated with the increased risk of DOR. https://doi.org/10.1289/EHP11309.

Lactic acid bacteria with a strong antioxidant function isolated from "Jiangshui," pickles, and feces

Excessive free radicals and iron death lead to oxidative damage, which is one of the main causes of aging and diseases. In this field of antioxidation, developing new, safe, and efficient antioxidants is the main research focus. Lactic acid bacteria (LAB) are natural antioxidants with good antioxidant activity and can regulate gastrointestinal microecological balance and immunity. In this study, 15 LAB strains from fermented foods ("Jiangshui" and pickles) or feces were evaluated in terms of their antioxidant attributes. Strains with strong antioxidant capacity were preliminarily screened by the following tests: 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical, superoxide anion radical scavenging capacity; ferrous ion chelating assay; hydrogen peroxide tolerance capacity. Then, the adhesion of the screened strains to the intestinal tract was examined using hydrophobic and auto-aggregation tests. The safety of the strains was analyzed based on their minimum inhibitory concentration and hemolysis, and 16S rRNA was used for molecular biological identification. Antimicrobial activity tests showed them probiotic function. The cell-free supernatant of selected strains were used to explore the protective effect against oxidative damage cells. The scavenging rate of DPPH, hydroxyl radicals, and ferrous ion-chelating of 15 strains ranged from 28.81-82.75%, 6.54-68.52%, and 9.46-17.92%, respectively, the scavenging superoxide anion scavenging activity all exceeded 10%. According to all the antioxidant-related tests, strains possessing high antioxidant activities J2-4, J2-5, J2-9, YP-1, and W-4 were screened, these five strains demonstrated tolerance to 2 mM hydrogen peroxide. J2-4, J2-5, and J2-9 were Lactobacillus fermentans and γ-hemolytic (non-hemolytic). YP-1 and W-4 were Lactobacillus paracasei and α-hemolytic (grass-green hemolytic). Although L. paracasei has been proven as a safe probiotic without hemolytic characteristics, the hemolytic characteristics of YP-1 and W-4 should be further studied. Due to the weak hydrophobicity and antimicrobial activity of J2-4, finally, we selected J2-5, J2-9 for cell experiment, J2-5 and J2-9 showed an excellent ability that resistant to oxidative damage by increasing SOD, CAT, T-AOC activity of 293T cells. Therefore, J2-5, and J2-9 strains from fermented foods "Jiangshui" could be used as potential antioxidants for functional food, health care, and skincare.

Profiles of novel high-molecular-weight synthetic antioxidants in urine and associated child exposure in China

The aim of this study is to investigate the exposure of novel high-molecular-weight (HMW) synthetic antioxidants (AOs), including nine synthetic phenolic antioxidants (SPAs), one low-molecular-weight (LMW) SPA, two organophosphite antioxidants (OPAs) as well as one transformation product in children's urine from eastern (n = 82) and western (n = 105) China. For the first time, all analytes were detected in children's urine such as the representative HMW SPAs pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate) (AO1010, median = 0.447 ng/mL), octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (AO1076, median = 0.0300 ng/mL), and 1,3,5-tris[(3,5-di-tert-butyl-4-hydroxyphenyl)methyl]-1,3,5-triazinane-2,4,6-trione(1,2-dioxoethylene)bis(iminoethylene) (AO3114, median = 0.0166 ng/mL) and representative OPAs bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite (AO626, median = 0.00216 ng/mL), tris(2,4-di-tert-butylphenyl) phosphite (AO168, median = 0.0296 ng/mL) as well as its transformation product tris(2,4-di-tert-butylphenyl) phosphate (AO168O, median = 1.53 ng/mL). Significant differences were observed in the concentrations of AO1010, AO3114, AO168, and AO168O between urine samples from eastern and western China (p < 0.01). The high-frequency combination of AOs from binary to a mixture of six AOs was acquired, which would provide a better investigation of the mixture toxicity. The high estimated daily intakes of AO1010 (85.4 ng/kg/day), AO1076 (10.2 ng/kg/day), AO3114 (4.50 ng/kg/day), and AO168 (1231 ng/kg/day) were less than the values of the tolerable daily intake (3,020,000, 1,500,000, 10,000,000, and 580,000 ng/kg/day for AO1010, AO1076, AO3114, and AO168, respectively), indicating low health risk to children. Our findings showed the co-occurrence of those novel AOs and transformation products in children, the overall risks associated with the mixture of transformation products and the mixture with other emerging pollutants need to be considered when assessing the risks of AOs in further studies.

Prevalence of Novel and Traditional Synthetic Phenolic Antioxidants in Baby Food from China: A Dominant Pathway for Infant Exposure

Synthetic phenolic antioxidants (SPAs) are a group of ubiquitous contaminants with multiple toxicities. However, current knowledge on the occurrence of SPAs in baby food and associated infant exposure is lacking. Herein, we analyzed three categories of baby food from China: infant formula, cereal, and puree, for a broad suite of 11 traditional and 19 novel SPAs. In addition to 11 traditional SPAs, up to 13 novel SPAs were detected in the baby food samples. The median concentrations of novel SPAs for infant formula, cereal, and puree were 604, 218, and 24.1 ng/g, respectively, surpassing those of traditional SPAs (53.4, 62.1, and 10.0 ng/g). The prevalent SPAs in the samples were butylated hydroxytoluene, 2,4-di-tert-butylphenol, pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (AO 1010), and octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (AO 1076). Source analysis indicated that the prevalence of these four SPAs in baby food was associated with contamination of packaging materials, mechanical processing, or raw ingredients. Migration experiments demonstrated that contamination of plastic packaging constituted an important source. Exposure assessment suggested that there may be no appreciable health risk posed by the SPAs in baby food. Even so, baby food consumption was still a dominant pathway for infant exposure to SPAs, with a higher contribution than breast milk consumption, dust ingestion, dermal dust absorption, and air inhalation, which requires special attention.

Sustainable recovery of phenolic antioxidants from real olive vegetation water with natural hydrophobic eutectic solvents and terpenoids

Olive oil production leads to the generation of olive mill wastewater (OMWW). Due to the presence of phenolic compounds, they are difficult to process, but they represent a source of high-added value chemicals since they have antioxidant and therapeutic properties. This work has studied the extraction of phenolic compounds from a type of OMWW, olive vegetation water, which presents these compounds in a more diluted dosage than in other studied to date, to revalue this waste stream. A real olive vegetation water from a Spanish olive oil producer was used, and liquid-liquid extraction was applied. Terpenoids and terpene-based hydrophobic eutectic solvents were systematically used to extract phenolic compounds following the concentrations of tyrosol, catechol, caffeic acid, and total phenolic content. By molecular simulation with the COSMO-RS method, 4 terpenoids, and 2 eutectic solvents were selected and compared with 2 conventional solvents. The Solvent/Feed ratio in the extraction of phenolic compounds was studied, showing that the solvents with the highest extraction results were geraniol, eucalyptol, and eutectic solvent menthol + camphor, which outperformed conventional solvents methyl isobutyl ketone and diisopropyl ether. Menthol + camphor gave total phenol extraction yields of 88.73% at a Solvent/Feed ratio in volume of 0.50, surpassing all solvents tested. A solvent reuse and regeneration process was applied by back-extraction of the 4 solvents: FTIR results showed the stability of the solvents while maintaining yields in the solvent reuse process. The phenolic compounds could be concentrated in the alkaline phase to factors up to 49.3 to the initial concentration in olive vegetation water. The alkaline phases were neutralized to obtain a precipitate with a caffeic acid content of up to 26 % wt%, and a tyrosol-rich supernatant with a concentration of up to 6.54 g/L. This work proposes a process using natural solvents to extract phenolic compounds from olive vegetation water.

A New Route of Valorization of Petrochemical Wastewater: Recovery of 1,3,5-Tris (4-tert-butyl-3-hydroxy-2,6-dimethyl benzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione (Cyanox 1790) and Its Subsequent Application in a PP Matrix to Improve Its Thermal Stability

The various chemicals in industrial wastewater can be beneficial for improving its circularity. If extraction methods are used to capture valuable components from the wastewater and then recirculate them throughout the process, the potential of the wastewater can be fully exploited. In this study, wastewater produced after the polypropylene deodorization process was evaluated. These waters remove the remains of the additives used to create the resin. With this recovery, contamination of the water bodies is avoided, and the polymer production process becomes more circular. The phenolic component was recovered by solid-phase extraction and HPLC, with a recovery rate of over 95%. FTIR and DSC were used to evaluate the purity of the extracted compound. After the phenolic compound was applied to the resin and its thermal stability was analyzed via TGA, the compound's efficacy was finally determined. The results showed that the recovered additive improves the thermal qualities of the material.

Use of cryoprotectors and antioxidants in sturgeon semen cryopreservation

In recent years, the possibility of increasing the low cryoresistance of sturgeon sperm by using antioxidants in basic cryoprotective media has been studied. The goal of this work was to review the current literature on impact of the cryoprotectors, well-known antioxidants and new multifunctional compounds on the activity indicators and fertilizing capability of sperm, as well as on biomarkers of cryostress. A special attention is given to the radical scavenging activity of studied compounds in relation to the highly reactive oxygen species, to prevent and negate oxidative stress damage of sturgeon sperm. Also, new trends for future research through the application of novel polyfunctional antioxidants to sturgeon sperm cryopreservation were indicated.

Effects of Fermentation Process on the Antioxidant Capacity of Fruit Byproducts

A substantial amount of fruit byproducts is lost annually due to lack of valorization applications at industrial scale, resulting in loss of valuable nutrients as well as immense economic consequences. Studies conducted clearly show that if appropriate and dependable methods are applied, there is the potential to acquire various components that are currently being obtained through synthetic manufacturing from fruit byproducts mostly regarded as waste and utilize them in not only the food industry, but pharmaceutical and cosmetic industries as well. This review aims to provide a concise summary of the recent studies regarding the fermentation of fruit byproducts and how their antioxidant activity is affected during this process.

Novel Hybrid Indole-Based Caffeic Acid Amide Derivatives as Potent Free Radical Scavenging Agents: Rational Design, Synthesis, Spectroscopic Characterization, In Silico and In Vitro Investigations

Antioxidant small molecules can prevent or delay the oxidative damage caused by free radicals. Herein, a structure-based hybridization of two natural antioxidants (caffeic acid and melatonin) afforded a novel hybrid series of indole-based amide analogues which was synthesized with potential antioxidant properties. A multiple-step scheme of in vitro radical scavenging assays was carried out to evaluate the antioxidant activity of the synthesized compounds. The results of the DPPH assay demonstrated that the indole-based caffeic acid amides are more active free radical scavenging agents than their benzamide analogues. Compared to Trolox, a water-soluble analogue of vitamin E, compounds 3a, 3f, 3h, 3j, and 3m were found to have excellent DPPH radical scavenging activities with IC₅₀ values of 95.81 ± 1.01, 136.8 ± 1.04, 86.77 ± 1.03, 50.98 ± 1.05, and 67.64 ± 1.02 µM. Three compounds out of five (3f, 3j, and 3m) showed a higher capacity to neutralize the radical cation ABTS^•+ more than Trolox with IC₅₀ values of 14.48 ± 0.68, 19.49 ± 0.54, and 14.92 ± 0.30 µM, respectively. Compound 3j presented the highest antioxidant activity with a FRAP value of 4774.37 ± 137.20 μM Trolox eq/mM sample. In a similar way to the FRAP assay, the best antioxidant activity against the peroxyl radicals was demonstrated by compound 3j (10,714.21 ± 817.76 μM Trolox eq/mM sample). Taken together, compound 3j was validated as a lead hybrid molecule that could be optimized to maximize its antioxidant potency for the treatment of oxidative stress-related diseases.

Environmental concentrations of 2, 4-DTBP cause immunotoxicity in zebrafish (Danio rerio) and may elicit ecological risk to wildlife

Synthetic phenolic antioxidant 2,4-di-tert-butylphenol (2,4-DTBP) has gained growing concerns due to relatively high concentrations in aquatic ecosystems. There are, however, significant knowledge gaps regarding its potential toxicity to aquatic organisms. In this study, zebrafish (Danio rerio) larvae were exposed to 0.01, 0.1, or 1 μM 2,4-DTBP for 6 d. Transcriptomic analysis of larvae revealed that biological processes related to anti-inflammatory function of macrophage M2 lineage were inhibited by 0.01 μM 2,4-DTBP. Decreases of transcripts related to the IL1B-MYD88-NF-κB pathway (i.e., il1b, il1rl1, myd88, irak4, irak1, traf6, ikbkg, nfkbia, nfkb) and protein levels of NF-κB in larvae intestine confirmed anti-inflammatory effects of 2,4-DTBP. Subsequently, larvae exposed to 2,4-DTBP were challenged with E. coli and showed higher survival rate, suggesting sustained activation of inflammation via LPS can be attenuated by 2,4-DTBP. Moreover, histological examination revealed that intestine barrier was compromised and there was an imbalance of intestine macrophage homeostasis. Food intake was also reduced following exposure to 0.1 and 1 μM 2,4-DTBP. In addition, a risk assessment revealed that 2,4-DTBP in surface water pose low to high ecological risks to aquatic organisms. Taken together, exposure to environmentally relevant concentrations of 2,4-DTBP could negatively affect immune response in zebrafish and may elicit ecological risk in fish population.

Preparation and antioxidant activity of novel chitosan oligosaccharide quinolinyl urea derivatives

In the present study, four new chitosan oligosaccharide derivatives bearing quinolinyl urea groups were synthesized by reaction between 2-methoxyformylated chitosan oligosaccharide and aminoquinoline. The chitosan oligosaccharide derivatives were characterized by Fourier Transform Infrared (FTIR) and 1H Nuclear Magnetic Resonance (1H NMR) spectroscopy. The obtained results confirmed that chitosan oligosaccharide quinolinyl urea derivatives were successfully synthesized. Meanwhile, the antioxidant activities of different chitosan oligosaccharide derivatives were examined in vitro. Experimentally, it was demonstrated that chitosan oligosaccharide quinolinyl urea derivatives had superior antioxidant activity compared with chitosan oligosaccharide and the antioxidant effects were concentration-dependent. Especially, when the concentration was 1.6 mg/mL, their superoxide anion radical scavenging rates could reach to 72.35 ± 0.49%, 100.00 ± 0.21%, 84.63 ± 0.49%, and 87.22 ± 0.32%, respectively. And the hydroxyl radical scavenging rates could reach to 100.00 ± 0.82%, 98.49 ± 4.08%, 100.00 ± 5.76%, and 92.07 ± 5.10%. In addition, the cytotoxic activity of the prepared chitosan derivatives against L929 cells was determined by CCK-8 assay. The cell survival rates were all higher than 90%, which intuitively indicated that the samples had almost no cytotoxicity. The findings indicated that the enhanced antioxidant property and biocompatibility of these chitosan oligosaccharide quinolinyl urea derivatives could enlarge the scope of the application of chitosan oligosaccharide, particularly as an antioxidant in food packaging, biomedical, pharmaceutical, cosmetics industries and other fields.

Detection of Synthetic Antioxidants: What Factors Affect the Efficiency in the Chromatographic Analysis and in the Electrochemical Analysis?

Antioxidants are food additives largely employed to inhibit oxidative reactions in foodstuffs rich in oils and fat lipids, extending the shelf life of foodstuffs and inhibiting alterations in color, flavor, smell, and loss of nutritional value. However, various research has demonstrated that the inadequate use of synthetic antioxidants results in environmental and health problems due to the fact that some of these compounds present toxicity, and their presence in the human body, in high concentrations, is related to the development of some cancer types and other diseases. Therefore, the development of analytical methods for identifying and quantifying synthetic antioxidants in foodstuffs is fundamental to quality control and in ensuring consumer food safety. This review describes the recent chromatographic and electrochemical techniques used in the detection of synthetic phenolic antioxidants in foodstuffs, highlighting the main characteristics, advantages and disadvantages of these methods, and specific typical features, which include extraction methods for sample preparation and materials used in the working electrode construction, considering chromatographic and voltammetric methods, since these specific features influence the efficiency in the analysis.