Monitoring of Pesticide Residues in Chili Peppers Using International Pesticide Monitoring Data for Safety Management.

Repeated pesticide residue detection in chili peppers in the Republic of Korea has become a serious health concern. Thus, monitoring domestically grown and imported chili peppers for pesticide residues is of great significance. Here, we investigated pesticide residues detected in imported and domestically grown chili peppers using global pesticide residue monitoring data. Our analysis involved organizing inspection and detection data from different sources. Global pesticide residue monitoring data for chili peppers revealed 139 pesticide types, 43,532 inspections, and 3966 detections (detection rate, 9.11%). Peppers from Mexico were sampled the most (39,927 inspections) and showed the highest number of detected cases (2998 cases). Globally, the top 10 most frequently detected pesticides were clothianidin, imidacloprid, thiamethoxam, chlorpyrifos, thiacloprid, metalaxyl, myclobutanil, azoxystrobin, carbendazim, and cyhalothrin, with detection rates in the range of 10.52-28.66%. Furthermore, domestic chili pepper pesticide residue monitoring revealed 73 pesticide types, 3535 inspections, and 332 detected cases (detection rate, 9.39%), and the top 10 most frequently detected pesticides were chlorfenapyr, tebuconazole, flonicamid, dinotefuran, boscalid, pyraclostrobin, fluxametamide, thiamethoxam, pyridaben, and azoxystrobin, with detection rates in the range of 13.89-32.58%. These findings may serve as fundamental data for safety management related to chili pepper pesticide residues in the Republic of Korea.

Temporal Patterns of Angular Displacement of Endosomes: Insights into Motor Protein Exchange Dynamics.

The material transport system, facilitated by motor proteins, plays a vital role in maintaining a non-equilibrium cellular state. However, understanding the temporal coordination of motor protein activity requires an advanced imaging technique capable of measuring 3D angular displacement in real-time. In this study, a Fourier transform-based plasmonic dark-field microscope has been developed using anisotropic nanoparticles, enabling the prolonged and simultaneous observation of endosomal lateral and rotational motion. A sequence of discontinuous 3D angular displacements has been observed during the pause and run phases of transport. Notably, a serially correlated temporal pattern in the intermittent rotational events has been demonstrated during the tug-of-war mechanism, indicating Markovian switching between the exploitational and explorational modes of motor protein exchange prior to resuming movement. Alterations in transition frequency and the exploitation-to-exploration ratio upon dynein inhibitor treatment highlight the relationship between disrupted motor coordination and reduced endosomal transport efficiency. Collectively, these results suggest the importance of orchestrated temporal motor protein patterns for efficient cellular transport.

Determination of 57 pesticide residues in fishery products by GC tandem mass spectrometry combined with QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction.

An analytical method using GC-MS/MS combined with quick, easy, cheap, effective, rugged, and safe extraction was developed to determine 57 pesticides in fishery products. The limits of detection and quantification (LOD and LOQ, respectively) of the analytical method ranged between 0.91 and 2.12 ng/g wet mass and 3 and 7 ng/g wet mass, respectively. Moreover, the linearity of the calibration curves was acceptable (R2 > 0.99). The relative pesticide recoveries ranged between 53.87 and 127.2%, and reproducibility ranged between 0.25 and 10.87%. The pesticide residues in brown seaweed, eel, flatfish, shrimp, and abalone samples were analyzed using the developed analytical method, and the results indicate that most samples were not contaminated by the 57 target pesticides, except low levels (< 10 ng/g) of 1,1-dichloro-2,2-bis(4-chlorophenyl)ethene, alachlor, ametryn, isoprothiolane, and prometryn in several samples.

Effect of rice milling, washing, and cooking on reducing pesticide residues.

The effects of milling, washing, and cooking on etofenprox, flubendiamide, and tebufenozide levels in brown and polished rice were investigated by HPLC using a UV detector. The reduction rates of etofenprox, flubendiamide, and tebufenozide after milling were 68.74-93.16%, 64.49-90.25%, and 69.74-92.58%, respectively, 11.64-41.44%, 31.36-65.37%, and 31.61-73.79%, respectively, after washing brown rice, and 30.85-82.08%, 52.13-83.05%, and 43.04-83.89%, respectively, after washing polished rice. The residue levels of the three pesticides in brown rice decreased after electric and pressure cooking by 56.49 and 54.41%, 75.80 and 73.42%, and 70.01 and 71.27%, respectively, and the corresponding levels in polished rice decreased after electric and pressure cooking by 85.58 and 85.82%, 86.70 and 87.06%, and 89.89 and 89.68%, respectively. In conclusion, various processing methods decrease the residual levels of etofenprox, flubendiamide, and tebufenozide in rice.

From Homogeneity to Turing Pattern: Kinetically Controlled Self-Organization of Transmembrane Protein.

Understanding the spatial organization of membrane proteins is crucial for unraveling key principles in cell biology. The reaction-diffusion model is commonly used to understand biochemical patterning; however, applying reaction-diffusion models to subcellular phenomena is challenging because of the difficulty in measuring protein diffusivity and interaction kinetics in the living cell. In this work, we investigated the self-organization of the plasmalemma vesicle-associated protein (PLVAP), which creates regular arrangements of fenestrated ultrastructures, using single-molecule tracking. We demonstrated that the spatial organization of the ultrastructures is associated with a decrease in the association rate by actin destabilization. We also constructed a reaction-diffusion model that accurately generates a hexagonal array with the same 130 nm spacing as the actual scale and informs the stoichiometry of the ultrastructure, which can be discerned only through electron microscopy. Through this study, we integrated single-molecule experiments and reaction-diffusion modeling to surpass the limitations of static imaging tools and proposed emergent properties of the PLVAP ultrastructure.