Food allergy has become a global concern. Spleen tyrosine kinase (SYK) inhibitors are promising therapeutics against allergic disorders. In this study, a total of 300 natural phenolic compounds were firstly subjected to virtual screening. Sesamin and its metabolites, sesamin monocatechol (SC-1) and sesamin dicatechol (SC-2), were identified as potential SYK inhibitors, showing high binding affinity and inhibition efficiency towards SYK. Compared with R406 (a traditional SYK inhibitor), sesamin, SC-1, and SC-2 had lower binding energy and inhibition constant (K_i) during molecular docking, exhibited higher bioavailability, safety, metabolism/clearance rate, and distribution uniformity ADMET predictions, and showed high stability in occupying the ATP-binding pocket of SYK during molecular dynamics simulations. In anti-dinitrophenyl-immunoglobulin E (Anti-DNP-IgE)/dinitrophenyl-human serum albumin (DNP-HSA)-stimulated rat basophilic leukemia (RBL-2H3) cells, sesamin in the concentration range of 5–80 μmol/L influenced significantly the degranulation and cytokine release, with 54.00% inhibition against β-hexosaminidase release and 58.45% decrease in histamine. In BALB/c mice, sesamin could ameliorate Anti-DNP-IgE/DNP-HSA-induced passive cutaneous anaphylaxis (PCA) and ovalbumin (OVA)-induced active systemic anaphylaxis (ASA) reactions, reduce the levels of allergic mediators (immunoglobulins and pro-inflammatory cytokines), partially correct the imbalance of T helper (Th) cells differentiation in the spleen, and inhibit the phosphorylation of SYK and its downstream signaling proteins, including p38 mitogen-activated protein kinases (p38 MAPK), extracellular signal-regulated kinases (ERK), and p65 nuclear factor-κB (p65 NF-κB) in the spleen. Thus, sesamin may be a safe and versatile SYK inhibitor that can alleviate IgE-mediated food allergies.

In this study, the dissipation, terminal residues and dietary risk of the cyazofamid residue in three globally consumed minor crops, turnip (Brassica rapa L.), onion (Allium cepa L.) and romaine lettuce (Lactuca sativa L.) were assessed by supervised field trials at 6 locations of China in 2020. A reliable QuEChERS-LC-MS/MS method was developed for simultaneous analysis of cyazofamid and its primary metabolite, 4-chloro-5-p-tolylimidazole-2-carbonitrile (CCIM). The average recoveries of cyazofamid and CCIM in turnip, onion and romaine lettuce were 79%–97% and 77%–99%, respectively. The half-lives of cyazofamid in these crops were 5.7–6.5, 5.3–8.7 and 5.8–6.5 days in turnip, onion and romaine lettuce, respectively, with the final cyazofamid residues at harvest all lower than limit of quantitation (LOQ, 0.01 mg/kg). The turnip roots, onion bulbs and romaine lettuce leaves grown in China under Good Agricultural Practices conditions and harvested 10, 14 and 5 days, respectively, after the cyazofamid SC (100 g/L) application, would be reasonably safe for consumption by the general population. The maximum residue limit (MRL) values of cyazofamid could be tentatively set as 10 mg/kg for turnip leaves, 0.3 mg/kg for turnip roots, 0.05 mg/kg for onion bulbs, and 10 mg/kg for romaine lettuce leaves.

Chaenomeles speciosa (Sweet) Nakai cultivated widely in temperate regions possesses anti-inflammatory properties, however, the underlying molecular mechanisms remain not fully understood. In this study, a purified phenolic extract of C. speciosa rich in chlorogenic acid, procyanidin B1 and catechin (determined by HPLC-Q-TOF-MS/MS) exhibited dose-dependent anti-inflammatory effects on lipopolysaccharide (LPS)-treated RAW264.7 macrophages. The extract at 30 μg/mL was most potent and enabled most cells in normal morphology under LPS stimulation without causing cytotoxicity. The extract suppressed the levels of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β), and the mRNA and protein expressions of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). The mechanisms underlying such anti-inflammatory actions included the regulation of phosphorylation of related proteins to monitor the expressions of inflammatory mediators and genes in the nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Therefore, the phenolic extract from C. speciosa is a desirable anti-inflammatory agent for inflammatory conditions to meet the rising demand for natural and cost-effective therapeutics.

Three pectin fractions (water-soluble fraction (WSF), chelator-soluble fraction (CSF), and sodium carbonate-soluble fraction (NSF)) were obtained from Chinese dwarf cherry (Cerasus humilis) fruits. All of them were branched low methoxylated pectins with an amorphous or partially nanocrystalline nature and eight neutral monosaccharides (arabinose and galactose were most abundant). WSF, CSF and NSF had a degree of methylation (DM) of 35.82%, 14.85% and 7.13%, uronic acid (UA) content of 76.02%, 83.71% and 69.01%, and total protein content of 2.4%, 2.1% and 8.8%, respectively. Their molecular weights were 340.31, 330.16 and 141.31 kg/mol, respectively (analyzed by gel permeation chromatography (GPC)). WSF, CSF and NSF exhibited good rheological, thermal, emulsifying, emulsion-stabilizing, water-adsorbing, oil-binding, cholesterol-binding and antioxidant properties. NSF had the highest emulsifying, emulsion stabilizing, water-/oil-/cholesterol-binding and antioxidant capacities, followed by CSF. NSF had the highest viscosity (406.77 mPa·s), flowability, and resistance to heat-induced changes/damage, which may be related to its lowest polydispersity index, DM and UA content and highest protein content. The three pectin fractions with desirable characteristics can be used as food additives/ingredients and dietary supplements.