Determination of Pesticide Residues in Vine Leaves Using the QuEChERS Method and Liquid Chromatography-Tandem Mass Spectrometry.

Commercial viticulture necessitates regular pesticide applications to manage diseases and pests, raising significant concerns regarding pesticide residues among stakeholders. Due to health risks associated with these residues in Turkish vine leaves, the European Commission has increased the frequency of official control from 20% to 50%. Thus, the aim of this study was to determine multi-class pesticide residues in brined vine leaves from Turkey. A total of 766 samples of vine leaves were collected between May 2022 and June 2023. More than 500 residues were analyzed using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method, followed by liquid chromatography-tandem mass spectrometry. In-house validation data demonstrated that the analytical method exhibits fit-for-purpose performance in terms of linearity, accuracy, precision, and measurement uncertainty. Out of 766 samples analyzed, 180 samples (23.5%) contained one (131, 17.1%) or multiple (49, 6.4%) pesticides. Both the frequencies of occurrence and the rate of maximum residue level (MRL) exceedance increased in 2023 compared to 2022, with the MRL exceedance rate rising from 9.5% to 25.2%. Forty-three different residues were found in quantifiable concentrations and eight of them were non-approved. Among the residues, the non-systemic pyrethroid insecticides, lambda-cyhalothrin (8.0%) and cypermethrin (7.2%), were the two most frequently detected, with concentrations ranging from 0.010 to 0.248 mg kg-1 and from 0.011 to 0.533 mg kg-1, respectively. Turkey is a major exporter of vine leaves and these results provide crucial information regarding pesticide occurrence and quality assessment of vine leaves. The significant increase in both pesticide occurrence and MRL exceedance rates between 2022 and 2023 underscores the urgency for regulatory bodies to reassess current pesticide usage and monitoring practices. The findings emphasize the importance of implementing more stringent rules and improving enforcement methods in order to reduce the spread of unapproved pesticides and ensure adherence to global food safety standards.

Structural properties and biological activities of soluble dietary fibers rich in pectic-polysaccharides from different buckwheat green leaves.

Buckwheat green leaves are commonly consumed as functional tea materials due to their various beneficial effects. Although buckwheat green leaves have abundant soluble dietary fibers (SDFs), the information about their structural properties and functional properties remains unknown, largely hindering their applications as functional/health products. Hence, to enhance the usage and application of SDFs from buckwheat green leaves as value-added health products, the structures and biological activities of SDFs derived from different buckwheat green leaves were investigated and compared. Results revealed that SDFs derived from Tartary buckwheat green leaves (TBSDF) and common buckwheat green leaves (CBSDF) were rich in complex pectic-polysaccharides, mainly composing of homogalacturonan (HG) and rhamnogalacturonan I (RG I) pectic domains. Besides, TBSDF had higher proportion of RG I pectic domains than that of CBSDF. Furthermore, the existence of a high content of complex pectic-polysaccharides in TBSDF and CBSDF could contribute to their various biological activities, such as antioxidant, antiglycation, fat/bile acid binding, anticancer, and prebiotic effects. These results can provide some new insights into further development of buckwheat green leaves and related SDFs as value-added health products.

Identification and characterization of tsyl1, a thermosensitive chlorophyll-deficient mutant in rice (Oryza sativa).

Chloroplast development and chlorophyll biosynthesis are affected by temperature. However, the underlying molecular mechanism of this phenomenon remains elusive. Here, we isolated and characterized a thermosensitive yellow-green leaf mutant named tsyl1 (thermosensitive yellow leaf 1) from an ethylmethylsulfone (EMS)-mutagenized pool of rice. The mutant exhibits a yellow-green leaf phenotype and decreased leaf chlorophyll contents throughout development. At the mature stage of the tsyl1 mutant, the plant height, tiller number, number of spikelets per panicle and 1000 seed weight were decreased significantly compared to those of wild-type plants, but the seed setting rate and panicle length were not. The mutant phenotype was controlled by a single recessive nuclear gene on the short arm of rice chromosome 11. Map-based cloning of TSYL1, followed by a complementation experiment, showed a G base deletion at the coding region of LOC_Os11g05552, leading to the yellow-green phenotype. The TSYL1 gene encodes a signal recognition particle 54 kDa (SRP54) protein that is conserved in all organisms. The expression of tsyl1 was induced by high temperature. Furthermore, the expression of chlorophyll biosynthesis- and chloroplast development-related genes was influenced in tsyl1 at different temperatures. These results indicated that the TSYL1 gene plays a key role in chlorophyll biosynthesis and is affected by temperature at the transcriptional level.

A Narrative Review on Dietary Strategies to Provide Nitric Oxide as a Non-Drug Cardiovascular Disease Therapy: Beetroot Formulations-A Smart Nutritional Intervention.

Beetroot is a remarkable vegetable, as its rich nitrate and bioactive compound contents ameliorate cardiovascular and metabolic functions by boosting nitric oxide synthesis and regulating gene expressions or modulating proteins and enzyme activities involved in these cellular processes. Dietary nitrate provides a physiological substrate for nitric oxide production, which promotes vasodilatation, increases blood flow and lowers blood pressure. A brief narrative and critical review on dietary nitrate intake effects are addressed herein by considering vegetable sources, dosage, intervention regimen and cardioprotective effects achieved in both healthy and cardiovascular-susceptible individuals. Compared to other nitrate-rich vegetables, beets were proven to be the best choice for non-drug therapy because of their sensorial characteristics and easy formulations that facilitate patient adherence for long periods, allied to bioaccessibility and consequent effectiveness. Beets were shown to be effective in raising nitrate and nitrite in biological fluids at levels capable of promoting sustained improvement in primary and advanced hemodynamic parameters.

Simulated climate change decreases nutrient resorption from senescing leaves.

Nutrient resorption is the process whereby plants recover nutrients from senescing leaves and reallocate them to storage structures or newer tissues. Elemental resorption of foliar N and P has been shown to respond to temperature and precipitation, but we know remarkably little about the influence of warming and drought on the resorption of these and other essential plant macro- and micronutrients, which could alter the ability of species to recycle their nutrients. We conducted a 5 year manipulative field study to simulate predicted climate change conditions and studied the effects of warming (W), rainfall reduction (RR), and their combination (W+RR) on nutrient resorption efficiency in five coexisting shrub species in a semiarid shrubland. Both mature and senesced leaves showed significant reductions in their nutrient contents and an altered stoichiometry in response to climate change conditions. Warming (W, W+RR) reduced mature leaf N, K, Ca, S, Fe, and Zn and senesced leaf N, Ca, Mg, S, Fe, and Zn contents relative to ambient temperature conditions. Warming increased mature leaf C/N ratios and decreased N/P and C/P ratios and increased senesced leaf C/N and C/P ratios. Furthermore, W and W+RR reduced nutrient resorption efficiencies for N (6.3%), K (19.8%), S (70.9%) and increased Ca and Fe accumulation in senesced leaves (440% and 35.7%, respectively) relative to the control treatment. Rainfall reduction decreased the resorption efficiencies of N (6.7%), S (51%), and Zn (46%). Reductions in nutrient resorption efficiencies with warming and/or rainfall reduction were rather uniform and consistent across species. The negative impacts of warming and rainfall reduction on foliar nutrient resorption efficiency will likely cause an impairment of plant nutrient budgets and fitness across coexisting native shrubs in this nutrient-poor habitat, with probable implications for key ecosystem functions such as reductions in nutrient retention in vegetation, litter decomposition, and nutrient cycling rates.

[Analysis of constituents from different parts of Callicarpa nudiflora by UPLC-Q-TOF-MS/MS].

The aim of this study was to clarify the main components of the green leaves of Callicarpa nudiflora,and to compare the difference of main components between the green leaves,yellow leaves,branches and seeds. In this study,ultra-high performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS/MS) coupled with the UNIFI scientific information system was adopted. And the identification of the main chemical components of C. nudiflora was combined with reference materials,literatures and online database. In addition,the difference of main components was analyzed by Progenesis QI,principal component analysis(PCA) and orthogonal partial least squares discriminant(OPLS-DA). A total of 57 compounds were identified in green leaves,including phenylpropanoids,flavonoids and iridoids. Among them,the relative content of phenylethanoid glycosides was highest. Furthermore,the PCA analysis showed that there are significant differences in main components of the branches and other parts of C. nudiflora. Combined with OPLS-DA analysis,nudifloside,parvifloroside B and ß-hydroxysamioside were selected as the characteristic components for distinguish the leaves and branches of C. nudiflora. Our study provided a scientific basis for the collection and identification of C. nudiflora.

Assessing water-assisted UV-C light and its combination with peroxyacetic acid and Pseudomonas graminis CPA-7 for the inactivation and inhibition of Listeria monocytogenes and Salmonella enterica in fresh-cut 'Iceberg' lettuce and baby spinach leaves.

The effectiveness of ultraviolet C light (UV-C) delivered in water (WUV) or in peroxyacetic acid (PAA) for the inactivation and inhibition of L. monocytogenes and S. enterica in ready-to-eat 'Iceberg lettuce' and baby spinach leaves, was evaluated throughout chilled storage in modified atmosphere packaging (MAP). The inhibition of pathogen's growth by sequential pretreatments with UV-C in PAA and then biocontrol using Pseudomonas graminis CPA-7 was assessed during MAP storage at 5 °C and upon a breakage of the cold-storage chain. In fresh-cut lettuce, 0 1 kJ/m2 UV-C, in water or in 40 mg/L PAA, inactivated both pathogens by up to 2.1 ±â€¯0.7 log10, which improved the efficacy of water-washing by up to 1.9 log10 and showed bacteriostatic effects on both pathogens. In baby spinach leaves, the combination of 0 3 kJ/m2 UV-C and 40 mg/L PAA reduced S. enterica and L. monocytogenes populations by 1.4 ±â€¯0.2 and 2.2 ±â€¯0.3 log10 respectively, which improved water-washing by 0.8 ±â€¯0.2 log10. Combined treatments (0.1 or 0 3 kJ/m2 WUV and 40 mg/L PAA) inactivated both pathogens in the process solution from lettuce or spinach single sanitation, respectively. Pretreating lettuce with UV-C in PAA reduced L. monocytogenes and S. enterica's growth by up to 0.9 ±â€¯0.1 log10 with respect to the PAA-pretreated control after 6 d at 5 °C in MAP. Upon a cold-chain breakage, CPA-7 prevented S. enterica growth in PAA-pretreated lettuce, whereas showed no effect on L. monocytogenes in any of both matrices. Low-dose UV-C in PAA is a suitable preservation strategy for improving the safety of ready-to-eat leafy greens and reducing the risk of cross contamination.

Analysis of constituents from different parts of Callicarpa nudiflora by UPLC-Q-TOF-MS/MS / 中国中药杂志

The aim of this study was to clarify the main components of the green leaves of Callicarpa nudiflora,and to compare the difference of main components between the green leaves,yellow leaves,branches and seeds. In this study,ultra-high performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS/MS) coupled with the UNIFI scientific information system was adopted. And the identification of the main chemical components of C. nudiflora was combined with reference materials,literatures and online database. In addition,the difference of main components was analyzed by Progenesis QI,principal component analysis(PCA) and orthogonal partial least squares discriminant(OPLS-DA). A total of 57 compounds were identified in green leaves,including phenylpropanoids,flavonoids and iridoids. Among them,the relative content of phenylethanoid glycosides was highest. Furthermore,the PCA analysis showed that there are significant differences in main components of the branches and other parts of C. nudiflora. Combined with OPLS-DA analysis,nudifloside,parvifloroside B and β-hydroxysamioside were selected as the characteristic components for distinguish the leaves and branches of C. nudiflora. Our study provided a scientific basis for the collection and identification of C. nudiflora.

High-throughput analysis of amino acids in plant materials by single quadrupole mass spectrometry.

BACKGROUND: The amino acid profile of plants is an important parameter in assessments of their growth potential, resource-use efficiency and/or quality as food and feed. Screening studies may involve large number of samples but the classical amino acid analysis is limited by the fact that it is very time consuming with typical chromatographic run times of 70 min or more. RESULTS: We have here developed a high-throughput method for analysis of amino acid profiles in plant materials. The method combines classical protein hydrolysis and derivatization with fast separation by UHPLC and detection by a single quadrupole (QDa) mass spectrometer. The chromatographic run time is reduced to 10 min and the precision, accuracy and sensitivity of the method are in line with other recent methods utilizing advanced and more expensive mass spectrometers. The sensitivity of the method is at least a factor 10 better than that of methods relying on detection by fluorescence or UV. It is possible to downscale sample size to 20 mg without compromising reproducibility, which makes the method ideal for analysis of very small sample amounts. CONCLUSION: The developed method allows high-throughput analysis of amino acid profiles in plant materials. The analysis is robust and accurate as well as compatible with both free amino acids and protein hydrolysates. The QDa detector offers high sensitivity and accuracy, while at the same time being relatively simple to operate and cheap to purchase, thus significantly reducing the overall analytical costs compared to methods based on more advanced mass spectrometers.