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Microplastics (MPs) can adsorb toxic chemicals in biological or environmental matrixes and thus influence their behavior and availability. In order to investigate how the combined pollution of MPs and toxic organic chemical influence microbial growth and metabolism, Escherichia coli (E. coli) was grown in a complex, well-defined media and treated with polystyrene microplastics (PS MPs) and dichloro-diphenyl-tricgloroethane (DDT) at human relevant concentration levels. In vivo metabolites captured by a novel solid phase microextraction (SPME) probe, were used to reflect the metabolic dysregulation of E. coli under different pollution stresses. Results showed that the toxic effect of DDT displayed a distinct dose-dependent phenomenon while the existence of PS decreased the growth and metabolic interference effect of DDT on E. coli. Adsorption results revealed a mechanism that PS weakened the adverse impact of DDT by decreasing its free concentration in the treated culture media. Tricarboxylic acid (TCA) cycle related enzymes activities and antioxidant defense related substances of E. coli also proved the mechanism. The current study is believed to broaden our understanding of the ecotoxicity of MPs with toxic organic chemicals on microorganism.

The aroma fraction of fresh fruits is a key factor to evaluate quality and acceptance or resistance of customers. Due to the limited sensitivity of current analytical methods, many important aroma components are unidentified in most studies of fresh fruit. In this work, the aroma compounds in the fresh navel orange were studied by multidimensional gas chromatography quadrupole time-of-flight mass spectrometry which can simultaneously achieve one-dimensional and comprehensive two-dimensional separation on only one instrument, with no need to change columns. As a result, a total of 97 volatile compounds were determined by comprehensive two-dimensional gas chromatography while only 44 compounds were identified by one-dimensional gas chromatography. The identified compounds, which account for 98.30% of the volatile chemicals present in the orange, include 10 aldehydes, 8 ketones, 22 alcohols, 12 esters, 11 hydrocarbons and 34 terpenes. D-limonene was shown to be the predominant compound in fresh navel oranges. The results show that comprehensive two-dimensional gas chromatography provided reliable and comprehensive information on the aroma compounds in fresh navel oranges.

A lignin-biochar with high acidic oxygen-containing groups was produced via a facile simultaneous oxidization and carbonization of pulping lignin by using sulfuric acid for the first time. The lignin-biochars were investigated by 13C NMR, FTIR and XPS, and results demonstrated that treatment by sulfuric acid could oxidize part of aromatic ring side chain to introduce high acidic oxygen-containing group, especially carboxyl group. Their total acidic oxygen-containing groups of lignin-biochar including COOH and Ar-OH reached 8.64 mmol/g. Adsorption experiments were carried and the maximum adsorption capacity of lignin-biochar for Pb2+ reached 679 mg/g, which was significantly higher than other lignin-based or carbon adsorbents. Moreover, it could maintain high removal rate at high adsorption capacity. It also demonstrated that adsorption capability was proportional to the accessible carboxyl groups.

In this article, an ambient mass spectrometric method with molecularly imprinted polymer (MIP)-coated wooden tips was developed for sensitive analysis of trace macrolide antibiotics in complex food samples. A novel solid-phase microextraction (SPME) probe was prepared, via the modification of a layer MIP coating (with roxithromycin as template molecule) on the surface of wooden tips. The obtained MIP-coated wooden-tip SPME probe can be applied directly to enrich trace macrolide antibiotics from complex food samples, with enrichment factors of 244–1604, 72–370, and 12–82 folds for analysis of five investigated macrolide antibiotics in drinking water, honey, and milk samples, respectively. After extraction, a high voltage and some spray solvent were applied on the loaded SPME probe to desorb and ionize analytes enriched on the probe surface for electrospray ionization mass spectrometric (ESI-MS) analysis under ambient and open-air conditions. The method showed good linearity, with correlation coefficient values (r2) no less than 0.9904, and the calibration function was verified via Mandel's fitting test (p > 0.063). The limits of detection were in the range of 0.003–0.05, 1.1–5.1, and 1.9–15.8 ng/g for analysis of drinking water, honey, and milk samples, respectively. Recoveries of the five targeted macrolide antibiotics in honey and milk samples ranged from 73.4% to 98.1%, with the standard deviations no higher than 8.6%. As a result, MIP-coated wooden-tip ESI-MS method could be feasibly used as a sensitive method for determination of trace macrolide antibiotics in complex food samples.

Compounds extracted from essential oil of the Lavandula angustifolia by steam distillation were analysed by gas chromatography with quadrupole time-of-flight mass spectrometry (GC-QTOF/MS) and their anti-inflammatory activity were tested by a 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced inflammation method. The GC-QTOF/MS analysis identified 50 constituents, all representing 96.89% of the essential oil total composition. In particular, match factors, accurate mass and retention indexes were used to improve the accuracy of qualitative results. The main compounds identified were linalyl acetate (28.89%), linalool (24.30%), caryophyllene (7.89%), (E)-3,7-dimethylocta-1,3,6-triene (4.64%), 4-terpineol (4.04%), acetic acid lavandulyl ester (3.49%), borneol (2.60%) and eucalyptol (2.05%). Regarding anti-inflammatory activity, the essential oil was effective against the TPA-induced inflammation in mouse ear. The inhibition effect of essential oils (100 mg/kg) on TPA-induced mouse ear edema was about 58.66%. Meanwhile, the expression levels of transcription factor, nuclear factor kappa-B (NF-κB), inflammatory cytokine, cyclooxygenase-2 (COX-2) and tumor necrosis factor (TNF-α) were also decreased significantly. The results in this study show essential oil had a better anti-inflammatory activity than that of ibuprofen at the same dosage, which demonstrated a great potential value in application.

Volatile components in Dalbergia cochinchinensis Pierre were analysed using a comprehensive two-dimensional gas chromatography with mass spectrometry method featuring a new solid-state modulator. Compared to one-dimensional gas chromatography, the number of detected peaks were significantly increased. A total of 45 major compounds were identified in this study and the forward and reverse match factors of these compounds were both above 800. The results showed that the volatile components in Dalbergia cochinchinensis Pierre were primarily aldehyde and ketone compounds such as benzaldehyde, cinnamaldehyde, 4-chromanone, 1-(2-hydroxyphenyl)ethanone and acetophenone. In addition, a semi-quantitative analysis was conducted to determine the contents of the detected compounds based on peak area percentage. Moreover, the repeatability of the comprehensive two-dimensional gas chromatography-mass spectrometry analysis in this study was quite satisfactory with relative standard deviations less than 12.7% for intraday and 17.3% for interday measurements.

Effect of CaO2 on cow dung rapid bio-drying technology was researched. A static aerobic composting system was applied to this experiment which combining natural ventilation with Turing in the process of composting. The physical characteristics of cow dung was observed and the compost temperature, moisture content, organic matter, total nitrogen, total phosphorus, potassium content was determined which in order to study the effect of CaO2 on rapid drying of cattle in the compost. In the initial stage of compost, adding CaO2 groups compared with the control group, the temperature rise faster, 4-6 days in advance to the thermophilic phase; at the end of composting, the CaO2 composition and moisture content decreased significantly to below 30%. The addition of CaO2 in fertilizer was shorten the composting time, extend the thermophilic phase, to provide sufficient oxygen meeting the growth needs of aerobic microorganisms. It convinced that the rapid bio-drying of dairy manure has a good effect and provided a new idea for the effective treatment of cow dung.