Search Results (161)

This study developed phospholipid-based liposomes loaded with extract from wild thyme (Thymus serpyllum L.) tea processing residues to enhance polyphenol stability and delivery. Liposomes were prepared with phospholipids alone or combined with 10–30 mol% cholesterol or β-sitosterol. The effect of different lipid compositions on encapsulation efficiency (EE), particle size, polydispersity index (PDI), zeta potential, stability, thermal properties, diffusion coefficient, and diffusion resistance of the liposomes was investigated. Liposomes with 10 mol% sterols (either cholesterol or β-sitosterol) exhibited the highest EE of polyphenols, while increasing sterol content to 30 mol% resulted in decreased EE. Particle size and PDI increased with sterol content, while liposomes prepared without sterols showed the smallest vesicle size. Encapsulation of the extract led to smaller liposomal diameters and slight increases in PDI values. Zeta potential measurements revealed that sterol incorporation enhanced the surface charge and stability of liposomes, with β-sitosterol showing the most pronounced effect. Stability testing demonstrated minimal changes in size, PDI, and zeta potential during storage. UV irradiation and lyophilization processes did not cause significant polyphenol leakage, although lyophilization slightly increased particle size and PDI. Differential scanning calorimetry revealed that polyphenols and sterols modified the lipid membrane transitions, indicating interactions between extract components and the liposomal bilayer. FT-IR spectra confirmed successful integration of the extract into the liposomes, while UV exposure did not significantly alter the spectral features. Thiobarbituric acid reactive substances (TBARS) assay demonstrated the extract’s efficacy in mitigating lipid peroxidation under UV-induced oxidative stress. In contrast, liposomes enriched with sterols showed enhanced peroxidation. Polyphenol diffusion studies showed that encapsulation significantly delayed release, particularly in sterol-containing liposomes. Release assays in simulated gastric and intestinal fluids confirmed controlled, pH-dependent polyphenol delivery, with slightly better retention in β-sitosterol-enriched systems. These findings support the use of β-sitosterol- and cholesterol-enriched liposomes as stable carriers for polyphenolic compounds from wild thyme extract, as bioactive antioxidants, for food and nutraceutical applications. Full article

Concerns about mycotoxin contamination by Alternaria spp. in tomato-based products emphasize the need for understanding the effect of the environment on their production. In the current study, we focused on three species frequently associated with tomato (A. alternata, A. solani, and A. tenuissima) by evaluating the effects of different temperatures (5 to 40 °C) and substrata (PDA and V8) on mycelial growth and the production of mycotoxins (alternariol, alternariol monomethyl ether, and tenuazonic acid). Both biological processes were supported between 5 and 35 °C, with optimal temperatures between 20 and 30 °C, depending on the species. Temperature and its interaction with species significantly (p < 0.05) affected both processes. However, the species factor alone was not significant (p > 0.05), indicating that environmental conditions affect Alternaria spp. growth and mycotoxin production more than the species itself does. Mathematical equations were developed to describe the effect of temperature on mycelial growth, as well as on the production of AOH, AME, and TeA, for each Alternaria species. High concordance (CCC ≥ 0.807) between observed and predicted data and low levels of residual error (RMSE ≤ 0.147) indicated the high goodness of fit of the developed equations, which may be used for the development of models to predict Alternaria contamination both in field and during post-harvest storage. Full article

Neonicotinoids (NEOs) are a class of systemic insecticides widely used in agriculture owing to their high efficacy and selectivity. As one of the most globally consumed beverages, tea may represent a potential dietary source of pesticide residues. However, limited research has examined NEO contamination in tea and its implications for human exposure, highlighting the need for further investigation. Therefore, this study comprehensively evaluated the residue characteristics, processing effects, and human exposure risks of six NEOs—dinotefuran (DIN), imidacloprid (IMI), acetamiprid (ACE), thiamethoxam (THM), clothianidin (CLO), and thiacloprid (THI)—in Chinese tea products. According to the findings, the primary pollutants, ACE, DIN, and IMI, accounted for 95.65% of the total NEO residues in 137 tea samples, including green, oolong, white, black, dark, and herbal teas. The highest total target NEO (∑₆NEOs) residue level was detected in oolong tea (mean: 57.86 ng/g). Meanwhile, IMI exhibited the highest residue level (78.88 ng/g) in herbal tea due to the absence of high-temperature fixation procedures. Concentrations of DIN in 61 samples (44.5%) exceeded the European Union’s maximum residue limit of 10 ng/g. Health risk assessment indicated that both the chronic hazard quotient (cHQ) and acute hazard quotient (aHQ) for adults and children were below the safety threshold (<1). However, children required special attention, as their exposure risk was 1.28 times higher than that of adults. The distribution of NEO residues was significantly influenced by tea processing techniques, such as full fermentation in black tea. Optimizing processing methods (e.g., using infrared enzyme deactivation) and implementing targeted pesticide application strategies may help mitigate risk. These results provide a scientific foundation for enhancing tea safety regulations and protecting consumer health. Full article

To achieve an efficient, non-destructive, and intelligent identification of tea plant seedlings under high-temperature stress, this study proposes an improved YOLOv11 model based on chlorophyll fluorescence imaging technology for intelligent identification. Using tea plant seedlings under varying degrees of high temperature as the research objects, raw fluorescence images were acquired through a chlorophyll fluorescence image acquisition device. The fluorescence parameters obtained by Spearman correlation analysis were found to be the maximum photochemical efficiency (Fv/Fm), and the fluorescence image of this parameter is used to construct the dataset. The YOLOv11 model was improved in the following ways. First, to reduce the number of network parameters and maintain a low computational cost, the lightweight MobileNetV4 network was introduced into the YOLOv11 model as a new backbone network. Second, to achieve efficient feature upsampling, enhance the efficiency and accuracy of feature extraction, and reduce computational redundancy and memory access volume, the EUCB (Efficient Up Convolution Block), iRMB (Inverted Residual Mobile Block), and PConv (Partial Convolution) modules were introduced into the YOLOv11 model. The research results show that the improved YOLOv11-MEIP model has the best performance, with precision, recall, and mAP50 reaching 99.25%, 99.19%, and 99.46%, respectively. Compared with the YOLOv11 model, the improved YOLOv11-MEIP model achieved increases of 4.05%, 7.86%, and 3.42% in precision, recall, and mAP50, respectively. Additionally, the number of model parameters was reduced by 29.45%. This study provides a new intelligent method for the classification of high-temperature stress levels of tea seedlings, as well as state detection and identification, and provides new theoretical support and technical reference for the monitoring and prevention of tea plants and other crops in tea gardens under high temperatures. Full article

The globe artichoke (Cynara cardunculus L. var. scolymus) is a Mediterranean crop valued for its edible capitula and bioactive compounds. Post-harvest residual leaves are among the main by-products of artichoke cultivation and remain largely underutilized. This study reports a comprehensive characterization of the residual leaves of Carciofo di Malegno, an Alpine artichoke landrace. Comparative analysis was conducted against leaves from two commercial cultivars and a commercial herbal tea product. HPLC analysis revealed that Carciofo di Malegno exhibited the lowest levels of secondary metabolites. Cynaropicrin content was 0.52 ± 0.03 mg/g, lower than in the commercial samples, while the phenolic compounds were below the quantification limit. Proximate analysis indicated a distinctive nutritional profile, with significantly higher ash (8.01 ± 0.04%) and crude fiber (35.75 ± 0.29%) contents compared to all reference samples. These findings highlight the potential of Carciofo di Malegno residual leaves as a sustainable source of nutrients for functional food and nutraceutical applications. Their low content of bitter sesquiterpene lactones may enhance palatability, supporting their valorisation within circular economy frameworks. Moreover, their use may contribute to the in situ conservation of this landrace, reinforcing the link between agrobiodiversity preservation and the sustainable exploitation of agricultural by-products. Full article

Sea buckthorn (Hippophae rhamnoides) is a valuable plant rich in biologically active compounds, mainly found in its berries and leaves. The harvesting process, which includes pruning, freezing, and shaking, leaves behind large amounts of biomass and juice-pressing residues, typically composted. The aim of this study is to expand knowledge of the valorization of sea buckthorn secondary raw materials by applying an innovative pressure cyclic solid–liquid (PCSL) extraction method and to develop value-added functional food products. Extraction was performed in 20 and 60 cycles, each lasting from 2 to 10 min. The highest concentrations of proanthocyanidins (5.51 g_CE/L) and total phenolics (12.42 g_GAE/L) were obtained under prolonged conditions, but the L-4 extract (20 cycles × 2 min) was selected for kombucha production due to its favorable balance between efficiency and sustainability. Microbial safety evaluation showed that kombucha with sea buckthorn leaf extract exhibited significantly stronger antimicrobial activity against tested pathogens compared to green tea kombucha. Additionally, sensory analysis revealed higher consumer acceptability of beverages enriched with sea buckthorn extracts. Shotgun metagenomic analysis identified high microbial diversity in the M. gisevii MI-2 starter culture and fermented kombucha products (227 bacteria and 44 eukaryotes), most of which (92.5% bacteria, 77.8% eukaryotes) remain viable and contribute to fermentation dynamics. New biotechnological strategies and genetic modifications raise concerns about the safe use of microorganisms in food production. To address these issues, these findings provide a foundation for future strategies aimed at the safe application of beneficial microorganisms in food biotechnology and support the long-term goals of the European Green Deal by promoting sustainable biomass valorization and circular economy advancement in the food sector. Full article

Native to South Africa, Bush tea is a plant that thrives in various climates. Cultural practices such as mineral nutrition, fertigation, pruning, and harvesting have been shown to influence bush tea’s quality, growth, and yield. This study set out to determine the effects of mulching and deficit irrigation on the growth, yield, and quality of bush tea. Three deficit irrigation treatments (0%, 30%, and 100% Crop evapotranspiration (ETc) on field capacity) and three mulch treatments (sawdust, black plastic mulch, and no mulch) were included in a two-factor experiment, which was set up in a randomized complete block design (RCBD) with three replications. Physiological and growth parameters were taken every two weeks. The number of branches was counted, and measurements of chlorophyll content and the proportion of radiation intercepted by the canopy were recorded. Yield and secondary metabolites such as sugar residuals, fatty acids, and phenols of bush tea were determined after harvest. Growing bush tea under various water regimes showed that a 30% water regime significantly enhanced plant growth characteristics, including the proportion of intercepted radiation, plant height, and both fresh and dry weight. Furthermore, under different water regimes, sawdust improved plant growth in bush tea grown in the field. Black plastic mulch and a 0% water regime produced more compounds beneficial to health than tea treated with half or full irrigation. The extraction of data for Proton Nuclear Magnetic Resonance (NMR) and Mass Spectrometry analyses was conducted for quality components. Our study did not show any distinct structural differences in the tea under different water regimes or mulching. Flavones, phenols, diterpenes, and gardoside were some of the most abundant compounds found in bush tea using mass spectrometry. Principal Component Analysis was performed on the NMR spectral data across 27 samples of bush tea. Full article

In this study, the compatibility of polycarboxylate ether-based water-reducing admixtures (PCE) with cements produced with different types and dosages of grinding aids (GA) was experimentally and statistically investigated. A total of 203 paste mixtures were prepared using seven different types of GA and one type of PCE at different dosages. The Marsh funnel flow time and mini-slump values of the mixtures were compared. A modeling study was performed using the experimental data. In this direction, Classical Regression Analysis (CRA), Multivariate Adaptive Regression Splines (MARS), and Artificial Neural Networks (AOMA-ANN) were applied. Innovative approaches, AOMA-ANN (AIP) and AOMA-ANN (ONIP), were introduced. The results showed adverse effects on flow performance with increased GA utilization, except for TEA-based GA. TEA-type GA had the lowest flow performance. AOMA-ANN (ONIP) exhibited the best performance in modeling. Marsh funnel flow-time modeling with AOMA-ANN (ONIP) considered parameters such as sieve residue at 60 microns, the number of molecules per fineness, the density of GA, the pH value of GA, and the PCE dosage. Mini-slump modeling with AOMA-ANN (ONIP) considered parameters such as sieve residue at 60 microns, the density of GA, the pH value of GA, and the PCE dosage. Full article

Polyphenols show promising application prospects as a novel natural disinfectant for drinking water. This study employed a simulated pipe network system to investigate the effects of tea polyphenols at an initial concentration of 5 mg/L on the characteristics of biofilm on pipe walls and microbial community succession patterns under different water ages (12–48 h). The results showed that with increasing water age, the tea polyphenol residual concentration gradually decreased, and the biofilm structure significantly evolved: the surface roughness increased from 5.57 nm to 32.8 nm, and the biofilm thickness increased from 40 nm to 150 nm. Microbial community diversity exhibited a trend of first increasing and then decreasing, with the Shannon index reaching its peak (2.847) at a water age of 36 h and remaining significantly higher than the control group (1.336) at all stages. High-throughput sequencing revealed a transition from a single dominant genus of Methylophilus (54.41%) at a water age of 12 h to a multi-genus coexistence pattern at a water age of 48 h, with Methylophilus (24.33%), unclassified_Saprospiraceae (21.70%), and Hydrogenophaga (16.52%) as the main dominant groups. Functional bacterial groups exhibited temporal changes, with biofilm colonization-related genera (Caulobacter, Sphingobium) reaching their peaks at 36 h, while special metabolic genera (Methylophilus, Hydrogenophaga) dominated at 48 h. Potential pathogens in the tea polyphenol treatment groups were effectively controlled at low levels (<0.21%), except for a temporary increase in Legionella (6.50%) at 36 h. Tea polyphenols’ selective inhibition mechanism helps suppress the excessive proliferation of specific genera and reduces the risk of potential pathogen outbreaks. This has important implications for ensuring the microbiological safety of drinking water. Full article

Insect odorant-binding proteins (OBPs) are promising molecular targets for developing novel pest management strategies by modulating chemoreception-driven behaviors. The tea gray geometrid Ectropis grisescens (Lepidoptera, Geometridae) is a major pest in tea plantations, causing substantial economic losses in China. In this study, we identified 18 OBPs from E. grisescens antennal transcriptome. All of the encoded proteins possessed N-terminal signal peptides and conserved cysteine residues, behaviors which are characteristic of insect OBPs. Phylogenetic analysis categorized these proteins into plus-C, minus-C, and classic OBP subfamilies. MEME motif analysis identified conserved sequence features potentially involved in odor detection. Tissue- and sex-specific expression profiling showed that EgriGOBP1-2, OBP3, OBP8, and OBP13 were highly expressed in the antennae of both sexes, suggesting roles in olfactory communication. Among them, EgriGOBP1-2, OBP3, and OBP13 exhibited similar expression levels between males and females, while other EgriOBPs were predominantly expressed in the legs, wings, or other tissues, indicating additional physiological functions beyond chemoreception. To investigate functional specificity, we selected antenna-enriched EgriGOBP2 for ligand-binding analysis. Fluorescence binding assays demonstrated that EgriGOBP2 exhibited broad binding affinity toward 8 of 12 host volatiles and 11 of 12 plant essential oil-derived volatiles. These combined findings lay the foundation for mechanistic studies of chemical recognition in E. grisescens and provide insights into the development of ecologically friendly pest control alternatives. Full article

This study presents the development of a zinc oxide (ZnO) nanorod-based sensor for the detection and quantification of residual pesticides commonly found in tea plantations, with a focus on quinalphos and thiamethoxam. Exploiting the unique electrical characteristics of ZnO nanorods, the sensor exhibits high sensitivity and selectivity in monitoring trace levels of pesticide residues. The detection mechanism relies on measurable changes in electrical resistance when the ZnO nanorod-coated electrodes interact with varying concentrations of the target pesticides. A performance evaluation was carried out using water samples spiked with different pesticide concentrations. The sensor displayed distinct response profiles for each compound: a linear resistance–concentration relationship for quinalphos and a non-linear, saturating trend for thiamethoxam, reflecting their differential interactions with the ZnO surface. Statistical analysis confirmed the sensor’s reliability, reproducibility, and consistency across repeated measurements. The rapid response time and ease of fabrication underscore its potential for real-time, on-site pesticide monitoring. This method offers a promising alternative to traditional analytical techniques, enhancing food safety assurance and supporting sustainable agricultural practices through effective environmental surveillance. Full article

This study evaluated the effects of tea residue combined with complex enzymes on the growth performance, serum biochemistry, meat quality, and intestinal microbiota of Xiangling fattening pigs. A total of 120 healthy Xiangling fattening pigs, with an average weight of 47.93 kg (±15.28 kg), were randomly assigned to five treatment groups, each comprising four replicates of six pigs. The control group (CON) received a basal diet; the experimental groups received a diet containing 5.8% fermented tea residue as an alternative energy and protein source (dry matter basis) and mixed additional 0 (CZ), 200 (M200), 400 (M400), and 800 (M800) complex enzymes. The trial lasted for 83 days. The results showed that tea residue and complex enzymes failed to affect growth performance (p > 0.05). Tea residue reduced the serum aspartate aminotransferase and alkaline phosphatase activities (p < 0.01), and complex enzyme supplementation lowered the total cholesterol levels and reduced the alanine aminotransferase activity (p < 0.05). Additionally, tea residue decreased the pH_24h and b*_1h values (p < 0.05), and complex enzyme supplementation increased the L*_24h value and pork shear force (p < 0.05). In terms of amino acid content, tea residue significantly elevated aspartic acid and inosine monophosphate (p < 0.05), and complex enzyme addition increased the glutamic acid, lysine, alanine, valine, tyrosine, isoleucine, leucine, and phenylalanine levels (p < 0.05). The 800 mg/kg complex enzyme group exhibited a reduction in the C10:0, C15:0, and C17:0 contents (p < 0.05). Microbial analysis showed that tea residue promoted the abundance of Oribacterium and Butyricicoccus, while enzyme supplementation enriched Eggerthellaceae, Oscillospirales, and Peptococcaceae. Overall, the combination of tea residue and complex enzymes improved the pork quality, enhanced metabolic health markers, and modulated the gut microbiota composition, with the 400 mg/kg enzyme dose (M400) achieving the most pronounced benefits. These findings suggest a potential feeding strategy for improving pork quality without compromising growth performance. Full article

This study investigates the potential use of biochar derived from residues—such as spruce wood, spent coffee grounds, tea waste, and nutshells—as a sustainable coal substitute—to enhance the decarbonization of European energetic systems and decrease the dependence on fossil fuels. The biomasses were pyrolyzed at 250–550 °C, analyzed for calorific value and composition, and evaluated for energy retention and mass loss. The results show significant energy density improvements, with optimal temperatures varying by material (e.g., spruce wood reached 31.56 MJ·kg⁻¹ at 550 °C, retaining 21.84% of its mass; spent coffee grounds peaked at 31.26 MJ·kg⁻¹ at 350 °C, retaining 37.53%). Economic analysis confirmed pyrolyzed biomass as a cost-effective alternative to coal, especially considering emission allowance costs. Integrating biomass pyrolysis into regional energy systems supports decarbonization, reduces emissions, and advances us towards a circular economy. Full article

In recent years, convolutional neural networks (CNNs) have become a potent tool for hyperspectral image classification (HSIC), where classification accuracy, computational cost, and generalization ability are the main focuses. In this study, a novel approach to hyperspectral image classification is proposed. A tandem spectral–spatial attention module (TAM) was designed to select significant spectral and spatial features automatically. At the same time, a dense pyramidal residual module (DPRM) with three residual units (RUs) was constructed, where feature maps exhibit linear growth; a dense connection structure was employed between each RU, and a TAM was embedded in each RU. Dilated convolution structures were used in the last two layers of the pyramid network, which can enhance the network’s perception of fine textures and features, improving information transfer efficiency. Tests on four public datasets, namely, the Pavia University, Salinas, TeaFarm, and WHU-Hi-HongHu datasets, were carried out, and the classification accuracies of our method were 99.60%, 99.95%, 99.81%, and 99.84%, respectively. Moreover, the method enhanced the processing speed, especially for large datasets such as WHU-Hi-HongHu. The training time and testing time of one epoch were 53 s and 1.28 s, respectively. Comparative experiments with five methods showed the correctness and high efficiency of our method. Full article

Developing a catalyst with excellent electrical conductivity and catalytic performance for on-site testing of residual imidacloprid is significant and challenging. In situ growth of Mo₂C nanodots on Co-induced N-doped carbon nanotubes (Co/Mo₂C/N-CNT) was synthesized to construct a molecularly imprinted electrochemical sensor for the detection of imidacloprid. The results proved that the catalytic performance of Co/Mo₂C/N-CNT for imidacloprid was over two times higher than those of Co/N-CNT and commercial CNT. This improvement was attributed to the formation of a heterostructure between Co species, Mo₂C, and N-CNT, which facilitated highly exposed catalytic active sites. Additionally, the abundant Mo₂C nano-dots promoted interfacial charge transfer to achieve optimal dynamics. The optimum preparation parameters of the catalysts were obtained by response surface methodology. By analyzing the relationship between different pH values and peak potential, as well as the influence of different scanning rates on peak potential, it was deduced that the possible electrocatalytic mechanism of imidacloprid involved the reduction of the nitro group to a hydroxylamine group and H₂O. Under optimal conditions, the limit of detection (LOD) was 0.033 × 10⁻⁶ mol·L⁻¹ (R² = 0.99698), and the linear range was 0.1 × 10⁻⁶~100 × 10⁻⁶ mol·L⁻¹. The application effect of the prepared sensor was evaluated by measuring the imidacloprid in two kinds of tea, indicating that the sensor possessed good sensitivity and selectivity, and was capable of meeting the requirements of on-site detection. Full article