Determination of Azole Fungicide Residues in Fresh Juice by Magnetic Solid Phase Extraction Based on Fe3O4@ZnAl-LDH@MIL-53(Al) Sorbent in Combination with High-Performance Liquid Chromatograph.

In this work, a magnetic adsorption material based on metal-organic framework (Fe3O4@ZnAl-LDH@MIL-53(Al)) was synthesized and used as an adsorbent in the process of magnetic solid phase extraction. Then, a high-performance liquid chromatograph was used to quantitatively detect triazole fungicides in samples. In order to verify the successful preparation of the material, a series of characterization analyses were carried out. Besides, the key parameters that may affect the extraction efficiency have been optimized, and under optimal conditions the three triazole fungicides showed good linearity in the range of 10-1000 µg/L (R2 ≥ 0.9796); Limit of detections were ranged from 0.013 to 0.030 µg/mL. Finally, the established method was applied to the detection of triazole fungicides in four fresh juice samples. The results showed that the target analyte was not detected in all the test samples. By detecting the recoveries (73.3-104.3%) and coefficient variation (RSD ≤ 6.8%) of triazole fungicides in fortified samples, it proved that this established method meets the requirements of pesticide residue analysis and showed excellent application potential.

Evolution and interaction relationship of "eco-economy" dual grid pattern in Lingwu City, Ningxia, China.

Strengthening ecological network construction is an important measure to improve urban ecological environment and protect biodiversity. With Lingwu City of Ningxia as an example, based on remote sensing and social and economic data, we comprehensively analyzed the "double network" (ecological network and social and economic landscape) pattern and their relationship by using morphological spatial pattern analysis, Linkage Mapper, and improved gravity model. The results showed that land use/cover changed dramatically from 2000 to 2020 in Lingwu City. The area of sandy land and grassland decreased sharply, that of forest and construction land increased, and industrial zones expanded rapidly. The connectivity and stability of "dual network" were improved. The intensive areas of human activities were distributed in urban area, oasis agricultural areas, and Ningdong energy industrial zone. The ecological source areas and ecological corridors were mainly distributed in the middle of the nature reserve, while some extended to the other three functional areas. The transportation corridor presented an "H" pattern that was dense in oasis agricultural area and Ningdong energy industrial zone, and connected between the two regions. The "double network" were centered around their respective functional area spaces and had interwoven distributions. The trend of the "double network" changed from conflict to coordinated situation, with obvious zoning and interaction in space. The oasis agricultural area and Ningdong energy industrial area destroyed the eco-logy in the early stage and improved that in the later stage. In the future, it is necessary to strengthen the coordination between ecological protection and social and economic development, which could improve ecological quality by combining measures such as improving the quality of ecological sources and corridors, constructing ecological nodes, and repairing ecological disturbance points.

Aspartoacylase suppresses prostate cancer progression by blocking LYN activation.

BACKGROUND: Globally, despite prostate cancer (PCa) representing second most prevalent malignancy in male, the precise molecular mechanisms implicated in its pathogenesis remain unclear. Consequently, elucidating the key molecular regulators that govern disease progression could substantially contribute to the establishment of novel therapeutic strategies, ultimately advancing the management of PCa. METHODS: A total of 49 PCa tissues and 43 adjacent normal tissues were collected from January 2017 to December 2021 at Zhongnan Hospital of Wuhan University. The advanced transcriptomic methodologies were employed to identify differentially expressed mRNAs in PCa. The expression of aspartoacylase (ASPA) in PCa was thoroughly evaluated using quantitative real-time PCR and Western blotting techniques. To elucidate the inhibitory role of ASPA in PCa cell proliferation and metastasis, a comprehensive set of in vitro and in vivo assays were conducted, including orthotopic and tumor-bearing mouse models (n = 8 for each group). A combination of experimental approaches, such as Western blotting, luciferase assays, immunoprecipitation assays, mass spectrometry, glutathione S-transferase pull-down experiments, and rescue studies, were employed to investigate the underlying molecular mechanisms of ASPA's action in PCa. The Student's t-test was employed to assess the statistical significance between two distinct groups, while one-way analysis of variance was utilized for comparisons involving more than two groups. A two-sided P value of less than 0.05 was deemed to indicate statistical significance. RESULTS: ASPA was identified as a novel inhibitor of PCa progression. The expression of ASPA was found to be significantly down-regulated in PCa tissue samples, and its decreased expression was independently associated with patients' prognosis (HR = 0.60, 95% CI 0.40-0.92, P = 0.018). Our experiments demonstrated that modulation of ASPA activity, either through gain- or loss-of-function, led to the suppression or enhancement of PCa cell proliferation, migration, and invasion, respectively. The inhibitory role of ASPA in PCa was further confirmed using orthotopic and tumor-bearing mouse models. Mechanistically, ASPA was shown to directly interact with the LYN and inhibit the phosphorylation of LYN as well as its downstream targets, JNK1/2 and C-Jun, in both PCa cells and mouse models, in an enzyme-independent manner. Importantly, the inhibition of LYN activation by bafetinib abrogated the promoting effect of ASPA knockdown on PCa progression in both in vitro and in vivo models. Moreover, we observed an inverse relationship between ASPA expression and LYN activity in clinical PCa samples, suggesting a potential regulatory role of ASPA in modulating LYN signaling. CONCLUSION: Our findings provide novel insights into the tumor-suppressive function of ASPA in PCa and highlight its potential as a prognostic biomarker and therapeutic target for the management of this malignancy.

Stereoselective behaviors and enantiomeric effects of paclobutrazol on microorganisms during Chinese cabbage pickling process.

Studies on the differences between chiral pesticide enantiomers have caused widespread concern in the last decade. In the current work, the selective behaviors and different biological activities of paclobutrazol enantiomers during Chinese cabbage pickling process were evaluated. Results of degradation kinetics indicated that when paclobutrazol reside in raw material (Chinese cabbage) and was introduced into the pickling process, the degradation rates of the two paclobutrazol enantiomers were significantly different, the half-lives of (2R, 3R)-paclobutrazol (R-paclobutrazol) and (2S, 3S)-paclobutrazol (S-paclobutrazol) were 18.24 and 6.19 d, respectively. Besides, the conversion between the two enantiomers could also be observed, and the conversion rate of R-paclobutrazol to S-paclobutrazol was slower than that of reverse process. In addition, from the analysis of 16S rRNA and ITS sequencing, we inferred that the degradation of paclobutrazol was probably due to the presence of Pseudomonas and Serratia. Moreover, there has a significant difference in biological activity between R-paclobutrazol and S-paclobutrazol and shown an obviously enantiomeric effects on microbial community composition of pickling system. Besides, the analysis of microbial community displayed R-paclobutrazol might inhibit the growth of Erwinia (a sort of plant pathogens). Results from this study served to enhance our understanding of chiral pesticide residues on food safety and the potential risks to human health.

[Spatial Distribution and Risk Assessment of Heavy Metals in Surface Sediments from the Middle and Upper Reaches of the Yangtze River].

The hydrological regime of rivers significantly changes after dam impoundment, which in turn affects the particle composition and heavy metal fractions of the river sediments. From June to July 2019, the sediments from 26 sampling sections were collected along the main stream of the Yangtze River from Panzhihua City in the upper reaches of the Yangtze River to Hukou City in the middle reaches of the Yangtze River. The concentrations and fractions of As, Cd, Co, Cr, Cu, Ni, Pb, and Zn were measured using the BCR three-step extraction procedure. The pollution status and potential ecological risk of heavy metals in sediments were evaluated using the geo-accumulation index, the sediment quality guideline, and the risk assessment coding method (RAC). The results showed that the average particle size of sediments in the upper reaches of the Yangtze River (Jinsha River cascade reservoir section and the Three Gorges reservoir section) decreased from upstream to downstream, the total concentrations of As and Zn increased, and the variation trend in the middle reaches was not obvious. The content of clay particles was significantly positively correlated with the acid-soluble fraction concentrations of Cd and Ni. Cd was mainly in the residual fraction (59.26%) and acid-soluble fraction (24.67%). Large parts of Cr and Ni were residual fractions accounting for 92.41% and 83.41%, respectively. As, Co, Cu, Pb, and Zn were mainly in the residual fraction and the reducible fraction. The order of decrease for the pollution degree (Igeo) of As, Cd, Co, Cr, Ni, and Zn was the Jinsha River, the middle reaches of the Yangtze River, and the Three Gorges Reservoir. The decrease order of bioavailability (RAC) of Cd, Co, Cr, Cu, Ni, and Zn was the Three Gorges Reservoir, the Jinsha River, and the middle reaches of the Yangtze River. The bioavailability of As and Pb decreased in the order of the middle reaches of the Yangtze River, the Three Gorges, and the Jinsha River. According to the classification of the RAC, Cd in the Three Gorges Reservoir area exhibited a high risk with the RAC accounting for 48.44%. Cu, Ni, and Zn showed a low or medium risk.

Enhancing intracellular NADPH bioavailability through improving pentose phosphate pathway flux and its application in biocatalysis asymmetric reduction reaction.

The intracellular NAD(P)H insufficiency is the key factor which limits the reduced product (such as chiral alcohols) synthesis by whole cell biocatalysis or microbial cell factory. In this paper, we reported a novel solution to increase NADPH supply through strengthening the pentose phosphate pathway (PPP) flux with overexpression of extra zwf (gene for glucose 6-phosphatedehydrogenase) and glk (gene for glucokinase) by recombinant Escherichia coli BL21(DE3)/pETDuet-1-glk-zwf and pET28a-bccr containing a carbonyl reductase gene bccr. The amount of intracellular NADPH was significantly increased from 150.3 µmol/L to 681.8 µmol/L after strengthening the PPP flux, which was 4.5-fold to that of the control. It was applied to improve the asymmetric reduction of 4-chloroacetoacetate to ethyl S-4-chloro-3-hydroxybutylate catalyzed by the BcCR, which increased the reaction yield 2.8-fold to the control. This strategy provides a new way to increase NADPH supply in E. coli cell factories.

Adsorption behavior of azole fungicides on polystyrene and polyethylene microplastics.

Agricultural plastic films and triazole fungicides are widely used in agricultural production process. Exposure to natural environment, agricultural plastic films will degrade into micron plastic particles, which will adsorb pesticide molecules and may affect their toxicity, biological activity and persistence. The long-term coexistence of microplastics (MPs) and triazole fungicides will bring potential harms to the agricultural ecological environment. Therefore, two kinds of triazole fungicides flusilazole (FLU) and epoxiconazole (EPO) were selected as cases and the adsorption behaviors of them on polystyrene and polyethylene were investigated. A series of factors which could affect the adsorption behavior were evaluated. Specifically, the particle size of MPs could affect its adsorption capacity, and the smaller the particle size, the stronger the adsorption capacity. Moreover, with the increase of pH value from 6.0 to 9.0, the adsorption capacity of MPs to target compounds gradually increased. The effect of ionic strength was evaluated by NaCl, and 0.05% of NaCl was beneficial to the adsorption process, while the continuous increase of NaCl concentration inhibited the adsorption. Oxalic acid and humic acid decreased the adsorption capacity of flusilazole on PE by 15.99-32.00% and PS by 35.02-48.67%, respectively. In addition, compared with the single pesticide system, the adsorption capacity of MPs for flusilazole and epoxiconazole in the binary pesticides system decreased by 36.13-37.93% and 44.36-51.35%, respectively, indicating that competitive adsorption occurred between the two pesticides. Meanwhile, the adsorption process was evaluated by adsorption kinetics and adsorption isotherms and were consistent with pseudo-second-order kinetic model and Freundlich isotherm model, respectively. Finally, several characterization analyses were conducted to investigated the adsorption mechanism, and hydrogen, halogen bonding and hydrophobic interaction proved to play an important role. The study on the adsorption behavior and mechanism of pesticide on MPs was the basis of assessing the risk of joint exposure.

Different degradation patterns and mechanisms of chiral contaminant enantiomers: beta-cypermethrin as a case study.

Studies often neglect the differences between enantiomers in soil chiral contaminants, and the molecular ecological mechanisms involved in enantiomer selective degradation behaviors remain elusive. In the present study, we used the stepwise regression analysis to establish the quantitative relationships between degradation rates and genes that determine different degradation patterns and mechanisms among enantiomers; and beta-cypermethrin (BCYM) was chosen as the target analyte. Stepwise regression analysis demonstrated the relationships established for different enantiomers varied even under the same conditions, and results from path analysis showed the same functional gene exhibited different direct and indirect contributions to different enantiomer degradation rates. The genome and primary microbial communities during different enantiomer degradation rates were also analyzed based on Illumina MiSeq next-generation sequencing technology, and the results indicated the soil microbial community structure and abundance varied during different enantiomer degradation rates. Results from this study served to enhance our understanding of the molecular biological mechanisms of chiral contaminant selective degradation behaviors under the context of functional genes and degrading microorganisms.

Fecal Microbiota Transplantation Ameliorates Active Ulcerative Colitis by Downregulating Pro-inflammatory Cytokines in Mucosa and Serum.

Background: Ulcerative colitis (UC) is a multi-factor disease characterized by alternating remission periods and repeated occurrence. It has been shown that fecal microbiota transplantation (FMT) is an emerging and effective approach for UC treatment. Since most existing studies chose adults as donors for fecal microbiota, we conducted this study to determine the long-term efficacy and safety of the microbiota from young UC patient donors and illustrate its specific physiological effects. Methods: Thirty active UC patients were enrolled and FMT were administered with the first colonoscopy and two subsequent enema/transendoscopic enteral tubing (TET) practical regimens in The First Affiliated Hospital of Anhui Medical University in China. Disease activity and inflammatory biomarkers were assessed 6 weeks/over 1 year after treatment. The occurrence of adverse events was also recorded. The samples from blood and mucosa were collected to detect the changes of inflammatory biomarkers and cytokines. The composition of gut and oral microbiota were also sampled and sequenced to confirm the alteration of microbial composition. Results: Twenty-seven patients completed the treatment, among which 16 (59.3%) achieved efficacious clinical response and 11 (40.7%) clinical remission. Full Mayo score and calprotectin dropped significantly and remained stable over 1 year. FMT also significantly reduced the levels of C-reactive protein (CRP), interleukin-1 beta (IL-1ß), and interleukin-6 (IL-6). The gut microbiota altered significantly with increased bacterial diversity and decreased metabolic diversity in responsive patients. The pro-inflammatory enterobacteria decreased after FMT and the abundance of Collinsella increased. Accordingly, the altered metabolic functions, including antigen synthesis, amino acids metabolism, short chain fatty acid production, and vitamin K synthesis of microbiota, were also corrected by FMT. Conclusion: Fecal microbiota transplantation seems to be safe and effective for active UC patients who are nonresponsive to mesalazine or prednisone in the long-term. FMT could efficiently downregulate pro-inflammatory cytokines to ameliorate the inflammation.

[Effect of Fang's scalp acupuncture on perceived stress and sleep structure in insomnia patients: a randomized controlled trial].

OBJECTIVE: To compare the efficacy on insomnia between Fang 's scalp acupuncture combined with conventional acupuncture and the simple conventional acupuncture. METHODS: A total of 66 patients with insomnia were randomly divided into an observation group (33 cases, 1 case dropped off) and a control group (33 cases, 2 cases dropped off). In the control group, the routine acupuncture therapy was applied to Shenmen (HT 7), Baihui (GV 20), Zhaohai (KI 6) and Sanyinjiao (SP 6), etc. Based on the treatment as the control group, Fang's scalp acupuncture therapy was supplemented at fuxiang tou, fuzang shangjiao, fuzang zhongjiao, siwei, etc. At these scalp points, the needles were inserted perpendicularly with flying needling technique and manipulated with trembling one. In either group, the treatment was given once daily, continuously for 2 weeks. Before and after treatment, separately, the score of Pittsburgh sleep quality index (PSQI) and the score of Chinese perceived stress scale (CPSS) were observed, as well as the parameters monitored by polysomnography, i.g. total sleep time (TST), sleep onset latency (SOL), wakefulness after the sleep onset (WASO), sleep efficiency (SE), the percentages of the time of rapid eye movement sleep phase (REM) and non-rapid eye movement sleep phase 1, 2, 3 and 4 in TST (REM%, N1%, N2%, N3%). The efficacy was compared between two groups. RESULTS: After treatment, the scores of each factor and the total scores of PSQI, as well as CPSS scores were all lower than those before treatment in the two groups (P<0.01, P<0.05); except the score for sleep quality, the score of each factor and the total score of PSQI, as well as CPSS score in the observation group were lower than those in the control group (P<0.01, P<0.05). After treatment, TST, SE%, REM% and N3% were increased and SOL, WASO, N1% were decreased as compared with before treatment in the two groups (P<0.01, P<0.05), and N2% in the observation group was decreased (P<0.01); SE%, REM% and N3% in the observation group were higher than the control group (P<0.05) and N1% and N2% were lower than the control group (P<0.05). The total effective rate was 93.8% (30/32) in the observation group, higher than 87.1% (27/31) in the control group (P<0.05). CONCLUSION: Fang 's scalp acupuncture, on the base of routine acupuncture, obviously improves the sleep quality and perceived stress and adjusts the sleep structure in the patients with insomnia.

Magnetic metal-organic framework MIL-100 (Fe)/polyethyleneimine composite as an adsorbent for the magnetic solid-phase extraction of fungicides and their determination using HPLC-UV.

Fe3O4@MIL-100 (Fe)/PEI are used for the first time as an adsorbent material for the extraction of pesticide residues (epoxiconazole, flusilazole, tebuconazole, and triadimefon) from food matrices. The adsorbent proposed (Fe3O4@MIL-100(Fe)/PEI) was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), thermogravimetric (TG) analysis, and vibrating sample magnetometer (VSM) techniques to evaluate the properties of the sorbent. Then, the Fe3O4@MIL-100 (Fe)/PEI was employed for the quantification of the four triazole fungicides in fruits and vegetables (apple, orange, tomato, cabbage, and cucumber) using HPLC-UV for separation and detection. During the extraction process, the main parameters such as amount of adsorbent, extraction time, pH value, ionic strength, eluting solvent, and eluting volume were optimized. Under the optimum conditions, good linearity of this method was observed for all analytes, with correlation coefficients (R2) ≥ 0.9908. The limits of detection (LODs) ranged from 0.021-3.04 µg kg-1. The extraction recoveries of the four triazole fungicides varied from 73.9 to 109.4% with relative standard deviations (RSD) in the range 0.5 to 6.2%. Compared with other MOFs, the modification of Fe3O4@MIL-100 (Fe) with PEI shows high efficient adsorption due to the combined benefits of MIL-100 (Fe) and PEI. The material is easily synthesized, has good stability, and is of low cost.  Graphical abstract.

The different toxic effects of metalaxyl and metalaxyl-M on Tubifex tubifex.

Metalaxyl and Metalaxyl-M are the fungicides that widely used in many countries. In this study, the environmental behaviors between metalaxyl and metalaxyl-M in Tubifex tubifex (T. tubifex) were quantitative analyzed by using a high performance liquid chromatography with photo-diode-array-detector (HPLC-DAD). Results demonstrated that there was no significant difference (p > 0.05) in the concentration of metalaxyl and metalaxyl-M in T. tubifex during the exposure process. However, the dissipation behaviors of metalaxyl and metalaxyl-M in T. tubifex were different (p < 0.05) during the non-exposure culture process. Meanwhile, the toxic effects were also evaluated by comparing the different influences of these two compounds on related physiological indicators, and functional enzyme activities. The survival rates of T. tubifex were 63.33 ± 15.28% (20 mg L-1), 63.33 ± 5.77% (200 mg L-1) treated with metalaxyl and were 50.00 ± 10.00% (20 mg L-1), 46.67 ± 11.55 (200 mg L-1) treated with metalaxyl-M at the non-exposure culture process. The autotomy rates were increased significantly compared with the initial in all treatments. Besides, the activities of CAT, SOD, and GST in T. tubifex were also inhibited by metalaxyl and metalaxyl-M treatments. Finally, the high-throughput transcriptome sequencing technology was applied to investigate the metabolic pathways of target analytes in T. tubifex, and results proved that the metabolic pathways associated with human diseases (such as viral myocarditis) were up-regulated expression for metalaxyl and metalaxyl-M treatments, and metalaxyl-M up-regulated more significantly. All the results demonstrated that metalaxyl-M had a higher toxicity than metalaxyl on T. tubifex.

Clinical Significance and Potential Role of LSM4 Overexpression in Hepatocellular Carcinoma: An Integrated Analysis Based on Multiple Databases.

Background: Hepatocellular carcinoma (HCC) is a solid tumor with high recurrence rate and high mortality. It is crucial to discover available biomarkers to achieve early diagnosis and improve the prognosis. The effect of LSM4 in HCC still remains unrevealed. Our study is dedicated to exploring the expression of LSM4 in HCC, demonstrating its clinical significance and potential molecular mechanisms. Methods: Clinical information and LSM4 expression values of HCC were obtained from Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases. Survival analysis and receiver operating characteristic (ROC) curve analysis were applied to evaluate the prognostic and diagnostic significance of LSM4. Calculating pooled standardized mean difference (SMD) and performing summary receiver operating characteristic (sROC) curve analysis to further determine its expression status and diagnostic significance. LSM4-related co-expressed genes (CEGs) were obtained and explored their clinical significance in HCC. LSM4-associated pathways were identified through Gene set enrichment analysis (GSEA). Results: Up-regulated LSM4 was detected in HCC tissues (SMD = 1.56, 95% CI: 1.29-1.84) and overexpressed LSM4 had excellent distinguishing ability (AUC = 0.91, 95% CI: 0.88-0.93). LSM4 was associated with clinical stage, tumor grade, and lymph node metastasis status (p < 0.05). Survival analysis showed that high LSM4 expression was related to poor overall survival (OS) of HCC patients. Cox regression analysis suggested that high LSM4 expression may be an independent risk factor for HCC. We obtained nine up-regulated CEGs of LSM4 in HCC tissues, and six CEGs had good prognostic and diagnostic significance. GSEA analysis showed that up-regulated LSM4 was closely related to the cell cycle, cell replication, focal adhesion, and several metabolism-associated pathways, including fatty acid metabolism. Conclusion: Overexpressed LSM4 may serve as a promising diagnostic and prognostic biomarker of HCC. Besides, LSM4 may play a synergistic effect with CEGs in promoting the growth and metastasis of HCC cells via regulating crucial pathways such as cell cycle, focal adhesion, and metabolism-associated pathways.

Magnetic Polydopamine Modified with Choline-Based Deep Eutectic Solvent for the Magnetic Solid-Phase Extraction of Sulfonylurea Herbicides in Water Samples.

A novel magnetic solid-phase extraction technique coupled to ultraperformance liquid chromatography has been developed for separation and preconcentration of four sulfonylurea herbicides (sulfosulfuron, bensulfuron-methyl, pyrazosulfuron-ethyl and halosulfuro-methyl) in aqueous samples. The key point of this method was the application of a novel magnetic nanomaterial that composed of a low eutectic solvent as a shell coated on the magnetic core modified by polydopamine. The extensive active sites outside the low eutectic solvent can effectively adsorb the target herbicide in the extraction process. The obtained magnetic adsorbent was characterized with fourier transform infrared spectrometry, scanning electron microscopy and vibrating sample magnetometer. The influence parameters relevant to this method were optimized. Under the optimum conditions, good linearities could be obtained within the range of 1.0-200 µg L-1 for all analytes, with correlation coefficients ≥0.9908. The limit of detections of the method was between 0.0074 and 0.0100 µg L-1 and the relative standard deviations were 1.1-3.6%. The enrichment factor is 66.6. In the final experiment, the proposed method was successfully applied to the analysis of sulfonylurea herbicides residue in environment and drinking-water samples, and the obtained recoveries were between 70.6% and 109.4%.

The potential risks of paclobutrazol residue on yogurt fermentation from the level of chiral enantiomers.

In recent years, pesticide residues in food have increasingly become the focus of public attention. However, the standard system of pesticide maximum residue limits in fermented food is imperfect, which can lead to potential safety risks to consumers. In this context, the aim of the study was to assess the potential effects of paclobutrazol residue on the yogurt fermentation process. We examined the stereoselective behaviors of the 2 paclobutrazol enantiomers from the perspective of chirality during the yogurt fermentation process. The results indicated that no significant degradation occurred for either of the 2 enantiomers (2R, 3R-paclobutrazol, 2S, 3S-paclobutrazol), and no visible enantiomer conversion behavior was observed. In addition, the reason paclobutrazol did not significantly degrade was explained from the perspective of the microbial function. Results from 16S rRNA sequencing indicated that paclobutrazol significantly affected the microbial composition and inhibited metabolic function of microorganisms to exogenous substances, which impeded the degradation of residual pesticide in yogurt. Furthermore, the stable residue of exogenous substance may cause potential food safety problems. Microbial α-diversity analysis indicated that fermentation time played a more important role on diversity than did paclobutrazol concentration. Moreover, Staphylococcus was found in yogurt after treatment with paclobutrazol; Staphylococcus aureus causes dangerous infectious diseases in humans. We devised a method to investigate the presence of pesticide residues during food fermentation and provided a theoretical basis for food safety assessment.

Magnetic solid-phase extraction based on nano-zeolite imidazolate framework-8-functionalized magnetic graphene oxide for the quantification of residual fungicides in water, honey and fruit juices.

In this work, zeolite imidazolate framework-8 (ZIF-8) functionalized magnetic graphene oxide (Fe3O4@APTES-GO/ZIF-8) was successfully synthesized and used as a novel adsorbent in magnetic solid-phase extraction (MSPE) for the determination of four triazole fungicides in water, honey and fruit juices. The main parameters such as extraction time, amount of adsorbent, the pH value of the sample, ionic strength, and desorption solvent which could affect the experiment results were optimization. Under the optimum condition, the obtained linearity of this method ranged from 1 to 1000 µg L-1 for all analytes, with correlation coefficients (R2) ≥ 0.9914. Limit of detections (LODs) and limit of qualifications (LOQs) of four triazole fungicides were ranged from 0.014 to 0.109 µg L-1 and from 0.047 to 0.365 µg L-1, respectively. Based on comparison with outcomes from other studies, Fe3O4@APTES-GO/ZIF-8-MSPE could provide high performance and achieve satisfied results for the analysis of trace triazole fungicides in complicated matrices.

Enantiomeric effect of paclobutrazol on the microorganism composition during wine fermentation.

Pesticide residues in food can bring potential risks to human health and has been widely concerned in recent years. In the current study, the influence of paclobutrazol, which resided in raw material (grape) on wine fermentation process, were investigated. The degradation kinetic results indicated that the enantiomers of paclobutrazol not be degraded during 30 days of fermentation process. In order to achieve the fermented microorganism information of diversity, community composition, and function, the analysis of 16S rRNA and ITS sequencing were performed. Results demonstrated that the dominant microorganisms multiplied and the microbial diversity in the samples decreased as the fermentation process progresses. Furthermore, the paclobutrazol stimulated the growth of Pichia, which was observed during wine fermentation and which may have an underlying impact on the quality of the wine. The above results inferred that paclobutrazol residue could disturb the microbial community stability during wine fermentation, and the stable existence of paclobutrazol will cause potential risks to food safety and human health. In this work, we have successfully devised a method to investigate the influences of pesticide residues in raw materials during food processing and conclusions from this study could provide basis for dietary risk assessment.

The enantioselective effects and potential risks of paclobutrazol residue during cucumber pickling process.

For decades, pesticides have been widely used for controlling pests and protecting crops around the world, and the food safety issues caused by these compounds have raised widespread concern. However, the different enantioselective behaviors and biological activities of chiral pesticide enantiomers are often ignored. In this work, a novel method was put forward to investigate the enantioselective effects and potential risks of two paclobutrazol enantiomers during cucumber pickling process. The degradation kinetics indicated that when paclobutrazol reside in cucumber and was introduced into the pickling process, the half-time of paclobutrazol isomers were significantly different (9.24 d and 16.6 d), and the conversion phenomenon between the two enantiomers could also be observed. In addition, results from 16S rRNA and ITS sequencing shown that (2R, 3R)-paclobutrazol and (2S, 3S)-paclobutrazol have an obviously enantiomeric effects on microbial community of pickling system and the degradation of paclobutrazol was probably attributed to the presence of Pseudomonas and Serratia. Finally, the microorganisms functions were found to be disrupted under the exposure of (2R, 3R)-paclobutrazol and metabolic function of microorganisms to xenobiotic was inhibited, which might cause potential risks to the quality of preserved foods. In summary, we have devised a method and provided a novel insight into the potential risks of chiral pesticide residues on food safety and human health.

Application of polydopamine functionalized magnetic graphene in triazole fungicides residue analysis.

In this work, a new analytical method based on polydopamine functionalized magnetic graphene (PDA@MG) adsorbent material has been developed to determine three triazole fungicides in water samples. As previous step, a novel polydopamine functionalized PDA@MG adsorbent material has been successfully prepared, which was characterized by fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscope (TEM), and vibrating sample magnetometer (VSM). Based on this novel material, a new magnetic solid phase extraction (MSPE) method coupled with high performance liquid chromatography (HPLC) has been established for the determination of triazole fungicides in water samples. The main factors which could affect the experimental results were optimized. Under the optimal conditions, good linarites has been achieved in the range of 0.2-50 µg L-1, with the correlation coefficients (R2) were between 0.9962 and 0.9996. The limits of detections (LODs) were 0.0048-0.0084 µg L-1, and the relative standard deviations (RSDs) were between 1.7% and 4.8%. In addition, enrichment factors (EFs) were 572-916 times, which showed triazole fungicides residues could be accurately extracted and analyzed in this way. In the final experiment, the established method was applied to the detection of target analyzes in water samples. Satisfied results could be obtained for tebuconazole, propiconazole, and flusilazole. The recoveries of five water samples were between 69.4% and 106.4%, and the RSD were between 1.0% and 6.5%. The development method is more easy, effective, green and environmental-friendly, and has potential for application.

Extraction of essential oil from Citrus reticulate Blanco peel and its antibacterial activity against Cutibacterium acnes (formerly Propionibacterium acnes).

Citrus is one of the largest output fruits in the word. In China, the major orange variety is the Citrus reticulate Blanco (Ponkan). The peels are discarded as waste material, its comprehensive utilization is urgently needed. In this work, hydrodistillation method was developed to extract citrus essential oil (EO) from Blanco peel. With the optimal extraction conditions, the EO yield was more than 3%. By GC-MS analysis, 53 compounds were identified from the citrus EO. Terpenes compounds accounted for 71.2%, especially d-limonene (major composition) accounted for 58.9%. The obtained citrus EO showed remarkable antibacterial activity against Cutibacterium acnes (C. acnes, Formerly P. acnes) and common microorganisms such as S. aureus, B. subtilis, and E. coli. Even compared with the common antibiotics (such as erythromycin, clindamycin, and tetracycline) for acne therapy, its antibacterial activity against C. acnes is more excellent. This work provides a potential therapy material for the treatment of acne.