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Curcumin possesses antioxidant, anti‐inflammatory, and other properties. However, this compound exhibits low bioavailability because of its poor solubility and stability. In this paper, lysozyme nanoparticles were fabricated through solvent evaporation, and then, the solubilization and protection capability of curcumin were investigated. Lysozyme nanoparticles were characterized by dynamic light scattering technique, atomic force microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. The load capacity and stability in thermal environment were further explored. Results showed that the lysozyme nanoparticle displayed a spherical structure (127.9 ± 2.12 nm) with favorable distribution. The solubility of curcumin can increase to 22 μg/mL. After encapsulation by lysozyme nanoparticles, the retentive curcumin can reach up to 67.9% and 30.25% at 25°C and 50°C, respectively, significantly higher than that of free curcumin. Meanwhile, experiments on DPPH free radicals indicated the curcumin loaded by lysozyme nanoparticle possessed higher free radical scavenging activity than that of free curcumin with same treatments. The results confirmed that lysozyme nanoparticles exhibit potential applications in solubilizing and protecting the environment‐sensitive hydrophobic functional components. [ABSTRACT FROM AUTHOR]

The plant hormone salicylic acid (SA) plays critical roles in plant innate immunity. Several SA derivatives and associated modification are identified, whereas the range and modes of action of SA‐related metabolites remain elusive. Here, the study discovered 2,4‐dihydroxybenzoic acid (2,4‐DHBA) and its glycosylated form as native SA derivatives in plants whose accumulation is largely induced by SA application and Ps. camelliae‐sinensis (Pcs) infection. CsSH1, a 4/5‐hydroxylase, catalyzes the hydroxylation of SA to 2,4‐DHBA, and UDP‐glucosyltransferase UGT95B17 catalyzes the formation of 2,4‐DHBA glucoside. Down‐regulation reduced the accumulation of 2,4‐DHBA glucosides and enhanced the sensitivity of tea plants to Pcs. Conversely, overexpression of UGT95B17 increased plant disease resistance. The exogenous application of 2,4‐DHBA and 2,5‐DHBA, as well as the accumulation of DHBA and plant resistance comparison, indicate that 2,4‐DHBA functions as a potentially bioactive molecule and is stored mainly as a glucose conjugate in tea plants, differs from the mechanism described in Arabidopsis. When 2,4‐DHBA is applied exogenously, UGT95B17‐silenced tea plants accumulated more 2,4‐DHBA than SA and showed induced resistance to Pcs infection. These results indicate that 2,4‐DHBA glucosylation positively regulates disease resistance and highlight the role of 2,4‐DHBA as potentially bioactive molecule in the establishment of basal resistance in tea plants. [ABSTRACT FROM AUTHOR]

Many soft-bodied animals have extensive peripheral nervous systems (PNS) with significant sensory roles. One such, the sea slug Pleurobranchaea californica, uses PNS computations in its chemotactile oral veil (OV) in prey tracking, averaging olfactory stimuli across the OV to target likely source direction, or "stimulus place". This suggests a peripheral subepithelial network (SeN) interconnecting sensory sites to compute the directional average. We pursued anatomy and connectivity of previously described ciliated putative sensory cells on OV papillae. Scanning electron microscopy (SEM) confirmed paddle-shaped cilia in clusters. Anti-tubulin and phalloidin staining showed connections to branching nervelets and muscle fibers for contraction and expansion of papillae. Ciliary cell processes could not be traced into nerves, consistent with sensory transmission to CNS via secondary afferents. Anti-tyrosine hydroxylase-stained ciliated cells in clusters and revealed an at least partially dopaminergic subepithelial network interconnecting clusters near and distant, connections consistent with PNS averaging of multiple stimulated loci. Other, unidentified, SeN neurotransmitters are likely. Confirming chemotactile functions, perfusible suction electrodes recorded ciliary spiking excited by both mechanical and appetitive chemical stimuli. Stimuli induced sensory nerve spiking like that encoding stimulus place. Sensory nerve spikes and cilia cluster spikes were not identifiable as generated by the same neurons. Ciliary clusters likely drive the sensory nerve spikes via SeN, mediating appetitive and stimulus place codes to CNS. These observations may facilitate future analyses of the PNS in odor discrimination and memory, and also suggest such SeNs as potential evolutionary precursors of CNS place-coding circuitry in the segmented, skeletonized protostomes and deuterostomes. [ABSTRACT FROM AUTHOR]

In order to clarify the relationship between withering process and green tea quality, dynamic changes in the major chemical components of green tea, including amino acids, catechins, caffeine (CAF) and gallic acid (GA), were investigated during withering at different times (ranging from 0 h to 21 h) and temperatures (15, 20 and 25 °C). One-way and two-way analyses of variance (ANOVA) with Duncan’s test were used to analyse the change of chemical components. Results showed that during the withering process, contents of most free amino acids increased with increasing withering time and temperature. Theanine (Thea) contents decreased slightly with fluctuations, glutamic acid (Glu) and aspartic acid (Asp) contents presented an increase–decrease pattern, whereas proline (Pro) contents remained almost constant. Total free amino acids increased up to 18 h but declined thereafter. Most catechins decreased with increasing withering time and temperature. In addition, GA contents increased with increasing time and temperature; while CAF contents increased with increasing withering time, but were only slightly correlated with withering temperature. This experiment recommended withering for 15–18 h below 25 °C to produce high quality green tea. [ABSTRACT FROM AUTHOR]

Summary: The tea plant is an economically important woody beverage crop. The unique taste of tea is evoked by certain metabolites, especially catechin esters, whereas their precise formation mechanism in different cell types remains unclear. Here, a fast protoplast isolation method was established and the transcriptional profiles of 16 977 single cells from 1st and 3rd leaves were investigated. We first identified 79 marker genes based on six isolated tissues and constructed a transcriptome atlas, mapped developmental trajectories and further delineated the distribution of different cell types during leaf differentiation and genes associated with cell fate transformation. Interestingly, eight differently expressed genes were found to co‐exist at four branch points. Genes involved in the biosynthesis of certain metabolites showed cell‐ and development‐specific characteristics. An unexpected catechin ester glycosyltransferase was characterized for the first time in plants by a gene co‐expression network in mesophyll cells. Thus, the first single‐cell transcriptional landscape in woody crop leave was reported and a novel metabolism pathway of catechin esters in plants was discovered. [ABSTRACT FROM AUTHOR]

To explore the relationship between the moisture content of withered tea leaves and their physical properties (i.e., elasticity, plasticity, flexibility, and texture) during withering, texture analyzer was employed to test the elasticity and flexibility of withered tea leaves with different moisture contents. The texture was evaluated by computer vision technology. The withered tea leaves with different moisture contents were used to process congou black tea, which was then subjected to sensory evaluation. Results showed that good elasticity, optimal flexibility, and plasticity were achieved when the moisture content of the withered tea leaves of Fudingdabai comprising two leaves and one bud varied arranging from 65.51 to 61.48%. The sensory evaluation of congou black tea revealed that moderate withering was better than long‐term withering and that both moderate and long‐term withering were better than no withering during processing. The moisture content was significantly correlated with the flexibility and plasticity of the withered tea leaves. Fresh tea leaves undergoing moderate withering with moisture content of 65.51–61.48% to process congou black tea, good tea shape and liquor color were achieved. This study provided new evidence that the moisture content of withered tea leaves significantly affected the quality of black tea. [ABSTRACT FROM AUTHOR]

Highlights: [•] We produced an aroma rich green tea LTPGT (low temperature processed green tea). [•] The odorant compounds of LTPGT were characterised by GC–MS/O and AEDA analyses. [•] Indole increased initially, peaking at 16h, then gradually decreased in LTPGT. [•] [15N]Anthranilic acid was converted to [15N]indole and [15N]OX-indoles in LTPGT. [Copyright &y& Elsevier]