Novel insight into the role of sulfur dioxide in fruits and vegetables: Chemical interactions, biological activity, metabolism, applications, and safety.

Sulfur dioxide (SO2) are a category of chemical compounds widely used as additives in food industry. So far, the use of SO2 in fruit and vegetable industry has been indispensable although its safety concerns have been controversial. This article comprehensively reviews the chemical interactions of SO2 with the components of fruit and vegetable products, elaborates its mechanism of antimicrobial, anti-browning, and antioxidation, discusses its roles in regulation of sulfur metabolism, reactive oxygen species (ROS)/redox, resistance induction, and quality maintenance in fruits and vegetables, summarizes the application technology of SO2 and its safety in human (absorption, metabolism, toxicity, regulation), and emphasizes the intrinsic metabolism of SO2 and its consequences for the postharvest physiology and safety of fresh fruits and vegetables. In order to fully understand the benefits and risks of SO2, more research is needed to evaluate the molecular mechanisms of SO2 metabolism in the cells and tissues of fruits and vegetables, and to uncover the interaction mechanisms between SO2 and the components of fruits and vegetables as well as the efficacy and safety of bound SO2. This review has important guiding significance for adjusting an applicable definition of maximum residue limit of SO2 in food.

Adsorption Properties of Anionic Dyes on Quaternized Microcrystalline Cellulose.

Efficient removal of dyes in the wastewater of dyeing and printing industries is challenging, especially the anionic dyes with strong stability, serious environmental pollution, and difficult degradation. In the present work, a novel cationic adsorbent was synthesized through the quaternization of 2,3-epoxypropyltrimethylammonium chloride (GTA) onto microcrystalline cellulose and characterized by Fourier transform infrared spectroscopy, X-ray diffraction, specific surface and pore size analysis, and scanning electron microscopy. Acid Yellow 128 (AY-128) and Acid Red 1 (AR-1) were selected to investigate their adsorption on quaternized microcrystalline cellulose (QMCC). The experimental adsorption results indicated that (1) the adsorption kinetics of AY-128 and AR-1 on QMCC could be consistent with the pseudo-second-order and Freundlich models, respectively; (2) the adsorption process was spontaneous and feasibly endothermic. The removal efficiency of AY-128 and AR-1 was up to 99 and 95%, respectively. After five times of reuse, the removal efficiency of AY-128 and AR-1 was still 97 and 95%. In conclusion, quaternized microcrystalline cellulose was a promising adsorbent for AY-128 and AR-1.

Sulfur dioxide maintains storage quality of table grape (Vitis vinifera cv 'Kyoho') by altering cuticular wax composition after simulated transportation.

The cuticular wax layer as a natural defensive barrier plays a key role in postharvest fruit quality maintenance. This study investigated the effects of simulated transport vibration (STV) on the berry quality and cuticular wax, and the ability of sulfur dioxide (SO2) to ameliorate STV damage in table grapes during cold storage. Results showed that STV damage accelerated the deterioration in grapes quality, and resulted in degradation and melting of cuticular wax, accompanied by a decrease in load of total wax, triterpenoids, fatty acids, alcohols, and olefins while an increase in alkanes and esters content during subsequent storage. However, SO2 effectively reversed the adverse impact of STV damage by increasing most wax fraction levels and corresponding genes expression, especially triterpenoids, although it had no apparent effect on wax structure. Overall, SO2 delayed the quality deterioration caused by vibration damage that occurs during transportation and storage by altering cuticular wax composition.

The detoxification of cellular sulfite in table grape under SO2 exposure: Quantitative evidence of sulfur absorption and assimilation patterns.

Sulfur dioxide (SO2) and its derivatives are known to be hazardous but their common application in food, especially the grape industry, is conditionally allowed. Potential hazards to consumers and the environment could occur upon the control-lost SO2 during grape logistics and storage. Researchers have usually focused on the anti-pathogen role of SO2 whereas limited efforts were conducted on the sulfur (S) absorption, assimilation patterns, and sulfite detoxification. In this study, short-term, room-temperature, and SO2-stored grapes were investigated, whose S flux of various forms was quantified through an estimation model. Accordingly, the additional accumulated S (0.50-0.86%) in pulps from atmospheric SO2 was considered mainly through rachis transport compared to across skin surfaces and the usage arrangement of the absorbed S was included. The first quantitative evidence of induced S assimilation under SO2 was also provided, which challenged the previous knowledge. In addition, sulfite oxidase and reductase (SiO and SiR) played major roles in sulfite detoxification, being effectively stimulated at multiple levels. The induced S metabolism associated with enhanced reactive oxygen species (ROS) scavenging capacity and alleviated senescence contributed to quality maintenance. Overall, these findings provide novel insights and are valuable supports for developing SO2-controlling strategies to avoid potential hazards.

The Jasmonic Acid Signaling Pathway is Associated with Terpinen-4-ol-Induced Disease Resistance against Botrytis cinerea in Strawberry Fruit.

Terpinen-4-ol, the main component of tea tree oil, markedly increases the disease resistance of postharvest strawberry fruit. To understand the mechanism underlying the enhancement of disease resistance, a high-throughput RNA-seq was used to analyze gene transcription in terpinen-4-ol-treated and untreated fruit. The results show that terpinen-4-ol induces the expression of genes in the jasmonic acid (JA) biosynthesis pathway, secondary metabolic pathways such as phenylpropanoid biosynthesis, and pathways involved in plant-pathogen interactions. Terpinen-4-ol treatment reduced disease incidence and lesion diameter in strawberry fruit inoculated with Botrytis cinerea. Terpinen-4-ol treatment enhanced the expression of genes involved in JA synthesis (FaLOX, FaAOC, and FaOPR3) and signaling (FaCOI1), as well as genes related to disease defense (FaPAL, FaCHI, and FaGLU). In contrast, treatment with the JA biosynthesis inhibitor salicylhydroxamic acid (SHAM) accelerated disease development and inhibited the induction of gene expressions by terpinen-4-ol. We conclude that the JA pathway participates in the induction of disease resistance by terpinen-4-ol in strawberry fruit. More generally, the results illuminate the mechanisms by which disease resistance is enhanced by essential oils.

Inhibition of miR-181a-5p reduces astrocyte and microglia activation and oxidative stress by activating SIRT1 in immature rats with epilepsy.

MicroRNAs regulate gene expression at the posttranscriptional level, and this process has been shown to be implicated in the pathological processes of temporal lobe epilepsy. At present, studies about the impact of microRNA-181a (miR-181a) on epilepsy have focused on hippocampal neurons, and the effect of miR-181a on other cells in the hippocampus remains poorly understood. Herein, we explored the role of miR-181a-5p in a lithium-pilocarpine model of epilepticus in immature rats. We found that the hippocampal expression level of miR-181a-5p was increased. Inhibition of miR-181a-5p protected the hippocampus against epilepsy, including hippocampal insults, neuronal apoptosis, astrocyte and microglia activation, neuroinflammation, oxidative stress, mitochondrial function, and cognitive dysfunction. Moreover, miR-181a-5p inhibition exerted a seizure-suppressing effect via SIRT1 upregulation. Overall, our findings reveal the potential role of the miR-181a-5p/SIRT1 pathway in the development of temporal lobe epilepsy, and this pathway may represent a novel target for ameliorating epilepsy and its sequelae.

Terpinen-4-ol Enhances Disease Resistance of Postharvest Strawberry Fruit More Effectively than Tea Tree Oil by Activating the Phenylpropanoid Metabolism Pathway.

This study aimed to reveal the effects and possible mechanism of terpinen-4-ol, the main component of tea tree oil (TTO), on the disease resistance of strawberry fruit. When the effects of TTO and its components were compared on the decay development in fruit inoculated with Botrytis cinerea after treatment, strawberry treated with terpinen-4-ol showed the lowest disease incidence (44.4%) after 48 h and also the smallest lesion diameter during the whole storage. This indicates that terpinen-4-ol induces the highest disease resistance in strawberry compared with TTO and other components. Untargeted metabolomic analysis showed that terpinen-4-ol treatment strongly activated phenylpropanoid biosynthesis and flavonoid metabolism pathway by increasing the accumulation of cinnamaldehyde, coniferyl aldehyde, naringenin, taxifolin, quercetin, and quercitrin in fruit at 12 h after treatment. In addition, terpinen-4-ol treatment also caused the accumulation of total phenolics and lignin by enhancing activities and relative gene expression of key enzymes in the phenylpropanoid metabolism pathway. These results suggest that terpinen-4-ol, as the key component of TTO, is the most important contributor to the effectiveness of TTO in improving disease resistance of strawberry fruit through activating the phenylpropanoid metabolism pathway.

Transcriptome analysis of Botrytis cinerea in response to tea tree oil and its two characteristic components.

Tea tree oil (TTO) and its two characteristic components (terpinen-4-ol and 1,8-cineole) have been shown to inhibit Botrytis cinerea growth. In this study, we conducted a transcriptome analysis to determine the effects of TTO and its characteristic components, alone and in combination, against B. cinerea. Most differentially expressed genes (DEGs) from B. cinerea cells treated with terpinen-4-ol participated in the biosynthesis of secondary metabolites, and the metabolism of amino acids, carbohydrates, and lipids. All treatments containing terpinen-4-ol potentially induced mitochondrial dysfunction and oxidative stress. These were further confirmed by the decreased activities of several enzymes (e.g., succinate dehydrogenase (SDH), malate dehydrogenase (MDH), α-ketoglutarate dehydrogenase (α-KGDH), isocitrate dehydrogenase (ICDH)), the increased activities of certain enzymes (e.g., catalase (CAT), peroxidase (POD), superoxide dismutase (SOD)), and increased content of hydrogen peroxide (H2O2). 1,8-Cineole mainly affected DEGs involved in genetic information processing, resulting in cell death. This study provides insight into the molecular mechanism of B. cinerea inhibition by TTO, and explains the synergistic effect of terpinen-4-ol and 1,8-cineole on B. cinerea.

Viral load and histological distribution of atypical porcine pestivirus in different tissues of naturally infected piglets.

A newly identified atypical porcine pestivirus (APPV) associated with congenital tremors in newborn piglets has been shown to have a worldwide geographic distribution. In view of the function of Erns in pestivirus infection and replication, the viral load and histological distribution of APPV in different tissues of naturally infected piglets were analyzed by quantitative RT-PCR and immunohistochemical detection using Erns as the target. The results showed that the viral copy number was higher in the cerebellum, submandibular lymph nodes, and thymus than in other tissues, indicating that these are important target organs of APPV. The histological distribution of APPV was mainly in the matrix and nerve fiber in nervous tissues, endothelial cells in lymphoid tissues, and epithelial cells in other tissues, suggesting that these cells were target cells of APPV. The results will provide basic data for elucidating the pathogenesis and deepening the understanding of this newly discovered pathogen.

Altered Expression of Zinc Transporter ZIP12 in Broilers of Ascites Syndrome Induced by Intravenous Cellulose Microparticle Injection.

Ascites syndrome (AS) is a harmful disease in fast-growing broilers characterized by heart failure and serious fluid accumulation in the abdominal cavity. One of the known functions of zinc transporter ZIP12 is an important regulator in pulmonary hypertension (PH) in rat. Whether chicken ZIP12 is involved in the process of AS need to be explored. Here, chicken ZIP12 was sequenced and expression pattern and histological distribution were detected in broilers of AS induced by intravenous cellulose microparticle injection. Phylogenetic analysis showed that ZIP12 was significantly different between chicken and mammalian. The relative mRNA expression level of ZIP12 in the liver and lung in AS and pre-ascites (PAS) groups were significantly higher (P < 0.01) than that in control. The immunohistological staining using rabbit anti-chicken ZIP12 IgG and integrated optical density analysis showed the positive cells of ZIP12 distributed in detected tissues and the expression level of ZIP12 protein increased in AS and PAS groups compared to control. The results will provide the basic data of ZIP12 in the pathological process of AS in broiler chickens and offer an important reference for prevention and control of the disease.

[Protective effect of amlodipine against contrast agent-induced renal injury in elderly patients with coronary heart disease].

OBJECTIVE: To evaluate the protective effect of amlodipine against contrast agent-induced renal injury in elderly patients with coronary heart disease. METHODS: A total of 189 elderly patients (>60 years) with coronary heart disease undergoing coronary artery angiography were randomly assigned into amlodipine group and control group to receive amlodipine or placebo, respectively, before and after administration of the contrast agent. At 24 h, 48 h and 5 days after contrast agent administration, the parameters of renal function were measured including serum cystatin C, urea nitrogen, creatinine, creatinine clearance rate, urine ß2-microglobulin, and urine N-acetyl-ß-glucosaminidase. RESULTS: In both groups, the contrast agents obviously affected the renal functions of the patients (P<0.05). At 24 h after contrast administration, the levels of serum cystatin C, urine ß2-microglobulin and urine NAG were significantly lower in amlodipine group than in the control group, but the other functional parameters showed no significant difference. At 48 h after contrast administration, the glomerular and tubular functional parameters were all superior in amlodipine group (P<0.05). At 5 days, the two groups showed significant differences in such glomerular and tubular functional parameters as urea nitrogen, creatinine, creatinine clearance rate, urine ß2-microglobulin, and urine NAG (P<0.05), but not in serum cystatin C level. The incidence of contrast agent-induced nephropathy was significantly lower in amlodipine group than in the control group (5/95 vs 10/94, P<0.05). CONCLUSIONS: Amlodipine offers protection against radiographic contrast agent-induced renal injury in elderly patients with coronary heart disease.