Development of a MOF-based SPE method combined with GC-MS for simultaneous determination of alachlor, acetochlor and pretilachlor in field soil.

In this work, a rapid, highly selective, reusable and effective method was developed for simultaneous determination of alachlor, acetochlor and pretilachlor in field soil by GC-MS coupled with MIL-101 based SPE. Main factors affecting the SPE by using MIL-101 were optimized. Moreover, by comparing with the other commercial materials such as C18, PSA and Florisil, the MIL-101(Cr) exhibited excellent adsorption performance, which aimed at amide herbicides. On the other hand, method validation displayed excellent method performance, achieving good linearities with r2 ≥ 0.9921, limits of detection between 0.25-0.45 µg kg-1, enrichment factors ≥ 89, matrix effect in the range of ± 20%, recoveries between 86.3% and 102.4%, and RSD lower than 4.38%. The developed method was successfully applied to the determination of amide herbicides in soil taken from the wheat, corn and soybean field at different depths, where the concentration of alachlor, acetochlor and pretilachlor were in the range of 0.62-8.04 µg kg-1. It was demonstrated that the more depth of soil, the lower of three amide herbicides. This finding could be proposed a novel method to detect the amide herbicides in the agriculture and food industry.

Temperature controlled microcapsule loaded with Perilla essential oil and its application in preservation of peaches.

In this study, Perilla frutescens essential oil (PEO) loaded microcapsules (PEOM) were successfully prepared and their thermal stability, temperature-responsive releasing effect, antioxidant activity, antibacterial activity, and preservation of peach were systematically investigated. PEOM showed excellent encapsulation efficiency (91.5%) with a core-shell ratio of 1.4:1 and exhibited high thermal stability, indicating that PEOM could effectively maintain PEO release rate. In vitro assays indicated that the optimal kinetic model for PEO release fitted well with first order with a diffusion mechanism. A high level of antioxidant and antibacterial activity of PEOM was maintained. In addition, owing to its sustained release, PEOM could prolong the shelf life of peaches significantly. Therefore, PEOM has potential application and development prospects in the field of food preservation.

Citral Essential Oil-Loaded Microcapsules by Simple Coacervation and Its Application on Peach Preservation.

Citral essential oil (CEO) was encapsulated by the single coalescence method, and its stability, release properties, and ability to maintain freshness were evaluated for the first time. The microshape characteristics of a CEO-loaded microcapsule (CM) were analyzed by inverted microscopy (OM) and scanning electron microscopy (SEM). The encapsulation efficiency, stability, and release behavior of CEO were evaluated using Fourier transform infrared spectroscopy (FTIR), thermogravimetric/differential thermal comprehensive analysis (TG/DSC), and gas chromatography mass spectrometry (GC/MS). Moreover, peaches were used to evaluate the preservation properties of the CEO-loaded microcapsule. The results showed that the microcapsule produced using simple coacervation had better microstructure and the ability to reduce and control the release of citral essential oil. The qualities of peaches, such as appearance changes, hardness, soluble solid content, total acids, and total bacterial counts, were significantly improved in the CM system during storage, in comparison with the control and cold storage groups. Therefore, the CM has potential applications and development prospects in the food, drug, and other industries.

[Chemical constituents from the seed coat of Juglans regia].

Fifteen compounds were isolated from the seed coat of Juglans regia by silica gel, MCI gel and Sephadex LH-20 gel column chromatography, as well as high preparative performance liquid chromatography. Their structures were identified as salidroside (1), (6S, 9S)-roseoside (2), (6S, 9R)-roseoside (3), blumenol C glucoside (4), byzantionoside B (5), 5-hydroxy-2-methoxy-1, 4-naphthoquinone (6), gallic acid (7), glycerol 1-(9Z-octadecenoate)-2-(9Z, 12Z-octadecadienoate)-3-(9Z, 12Z, 15Z-octadecatrienoate) (8), glycerol 1, 2, 3-tri-(9Z, 12Z-octadecadienoate) (9), glycerol 1, 2, 3-tri-(9Z, 12Z, 15Z-octadecatrienoate) (10), glycerol 1-hexadecanoate-2, 3-di-(9Z, 12Z-octadecadienoate) (11) on the basis of EI-MS, FAB-MS and NMR spectra. Moreover, 35 volatile compounds were identified by GC-MS.

Utility of 4-chloro-7-nitrobenzofurazan for the spectrofluorimetric determination of butylated hydroxyanisole and propyl gallate in foodstuffs.

UNLABELLED: A spectrofluorimetric method is presented for the determination of 2 synthetic phenolic antioxidants (SPAs), butylated hydroxyanisole (BHA), and propyl gallate (PG) in foodstuffs. The proposed method is based on the derivatization of SPAs with 4-chloro-7-nitrobenzofurazan (NBD-Cl) in phosphate buffer of pH 9.0 to yield a highly fluorescent brown product. The optimum experimental conditions have been studied carefully. Linear calibration curves were obtained over the concentration range of 0.20 to 40 µg mL⁻¹ for BHA, and 0.80 to 50 µg mL⁻¹ for PG, using NBD-Cl reagent. The detection limits were 18 ng mL⁻¹ for BHA, 55 ng mL⁻¹ for PG. Intra-day and inter-day relative standard deviations at 3 different concentrations were determined. The high recovery values indicate the accuracy of the proposed methods, and low relative standard deviation values indicate good precision. The results presented in this report show that the applied spectrofluorimetric method is acceptable for the determination of the 2 SPAs in the foodstuffs. Other SPAs, tertiary butyl hydroquinone and butylated hydroxytoluene in foodstuffs do not interfere with the proposed method. PRACTICAL APPLICATIONS: In this spectrofluorimetric method, NBD-Cl as a derivation agent is used to detect synthetic phenolic antioxidants. The method specificity has been greatly improved; there was no interference from other commonly used phenolic substances.

Antioxidant activity and chemical constituents of edible flower of Sophora viciifolia.

The antioxidant activities of crude extract and its derived soluble fractions from the flower of Sophora viciifolia were evaluated in five different test systems (DPPH, ABTS, FRAP, reducing power and inhibition of lipid peroxidant models) for the first time. The ethylacetate soluble fraction exhibited the highest antioxidant effect. Correlation analysis suggested that the flavonoids might be the major contributors for the high antioxidant activity of this flower. In addition, 11 compounds were isolated from this flower, and the antioxidant capacities of 5 flavonoids were evaluated by DPPH assay. Compound 3 (luteolin) had a significant DPPH radical-scavenging activity, and was also present at the highest concentration (5.56mg/gdrysample), implying an important role of 3 for the antioxidant activity of this flower. The study suggests that the flower of S. viciifolia can provide valuable functional ingredients and can be used for the prevention of diseases related to various oxidant by-products of human metabolism.

Four new phenanthrenes from Monomeria barbata Lindl.

Three biphenanthrene compounds (1-3) and a triphenanthrene compound (4), together with six known biphenanthrene compounds (5-10), were isolated from the tubers of Monomeria barbata Lindl. Their structures were elucidated on the basis of extensive spectroscopic analysis (1D-, 2D-NMR, and HR-ESI-MS). These four new compounds were tested in vitro for the cytotoxic activity against liver carcinoma (HepG-2), promyelocytic leukaemia (HL60), ovarian carcinoma (Skov-3) and epidermoid carcinoma (A431) cancer cell lines and the antioxidant activity in DPPH radical scavenging. Compounds 1-4 exhibited significant cytotoxic activity against HepG-2 and HL60 cell lines, and potent antioxidant activity in DPPH radical scavenging.

[Studies on the chemical constituents from the aerial parts of Gladiolus gandavensis].

OBJECTIVE: To study the chemical constituents of the aerial parts of Gladiolus gandavensis. METHODS: These compounds were isolated by silica gel, Sephades LH-20 and RP-18 column chromatographies. And their structures were elucidated by spectroscopic methods. RESULTS: Ten compounds were isolated, and their structures were identified as kaempferol (I), apigenin-7-O-alpha-L-rhamnoside(II), tamarixetin-3-robinobioside(III), nicotiflorin(IV), astragalin-2"-O-beta-D-glucopyranoside(V), quercetin-3-O-(6"-O-Ecaffeoyl)-beta-D-glucopyranoside(VI), beta-sitosterol(VII), daucosterol(VII), isopentylgentiobioside(IX), glycerol-alpha-monohexacosanate(X). CONCLUSION: Except for compounds VII and VIII, others compounds are obtained from this plant for the first time.

[Two diterpenoids from herbs of Huperzia serrata].

OBJECTIVE: To investigate the constituents from Huperzia serrata. METHOD: Two diterpenoid compounds were isolated by column chromatography with silica gel and Sephadex LH-20. The structures were elucidated by spectral analysis and X-ray crystallographic analysis. RESULT: Their structures were determined as (15R)-12, 16-epoxy-11, 14-dihydroxy-8, 11, 13-abietatrien-7-one (1) and 3beta-hydroxysandaracopimaric acid (2). CONCLUSION: Compound 1 was a new natural abietane-type diterpenoid, compound 2 was isolated from this plant for the first time.