Search Results (145)

Due to the roles of oxidative stress, inflammation, and neurotransmitter imbalances in cognitive and mental dysfunction, we aimed to develop a functional drink with antioxidant and anti-inflammatory properties as well as the potential to support neurotransmitter balance for improved cognition and mental health. The Teng Mo, Fen Hong Mee, and Hong Chon Su guava varieties were screened for their polyphenol and flavonoid contents, antioxidant and anti-inflammatory effects, and suppressive effects on acetylcholinesterase (AChE), monoamine oxidase (MAO), GABA transaminase (GABA-T), and glutamate decarboxylase (GAD). Juice from the cultivar with the highest potential was selected and mixed with mint and honey syrups, pomelo-derived dietary fiber, ascorbic acid, agar, water, and fruit puree (pear/apple/orange) to create three guava jelly drink formulations. The formulation with pear puree showed the highest biological potential and was selected as the final product. It is rich in vitamin C, gallic acid, and dietary fiber, and provides approximately 37 Kcal/100 g. It also promotes the growth of lactic acid-producing bacteria in the culture. Thus, our drink shows the potential to reduce oxidative stress and inflammation, improve neurotransmitter regulation, and stimulate the gut–brain axis, thereby promoting cognition and mental wellness. However, clinical research is essential to confirm these potential benefits. Full article

Fruit rot seriously damages pomelo production. Given concerns regarding the safety of chemical agents, biological alternatives are becoming more preferable. Therefore, the experiment aimed to (i) identify the pathogens causing pomelo fruit rot disease and (ii) select Trichoderma spp. strains controlling the determined pathogens in Ben Tre, Vietnam. Three pathogenic fungal strains isolated from diseased pomelo fruits were selected. The three pathogenic fungal strains were randomly injected into 9 healthy pomelo fruits. The strain PCP-B02-A2 led to a completely rotten fruit on day 17 after infection, while strains PCP-B02-B2 and PCP-B03-A1 had infected spots whose lengths were 17.5 and 28.1 mm, became larger, and eventually led to the whole fruit rot. The pathogens were identified by the internal transcribed spacer (ITS) technique as Colletotrichum gloeosporioides PCP-B02-A2, Pseudopestalotiopsis camelliae sinensis PCP-B03-A1, and P. chinensis PCP-B02-B2. Twenty-five Trichoderma spp. strains were isolated. The ITS technique identified four strains, including Trichoderma asperellum TP-B01, T. harzianum TP-B08, T. harzianum TP-B09, and T. asperellum TP-C25. The PCP-B02-A2 strain had antagonism at 66.7–68.7%, while those of PCP-B02-B2 and PCP-B03-A1 were 64.2–71.1% and 55.7–57.4%, respectively. Full article

In the context of agricultural green transformation, the balance between the environmental footprint and economic return is a key indicator for measuring the synergy of high yields, high efficiency, and environmental friendliness in agricultural systems. However, the pathways and mechanisms for achieving this synergy in orchard systems remain unclear. Based on a three-year field experiment in Pinghe County, Fujian Province, a comprehensive evaluation framework integrating life cycle assessment (LCA) was constructed. This framework was used to systematically analyze the differences in the net ecosystem economic benefit (EEB) and environmental impact of four fertilization regimes: the conventional farming regime with no mulching (A; 1084 kg N ha⁻¹, 914 kg P₂O₅ ha⁻¹, and 906 kg K₂O ha⁻¹), the conventional farming regime with mulching (B), the optimized fertilization regime with water–fertilizer integration (C; 250 kg N ha⁻¹, 200 kg K₂O ha⁻¹, 100 kg MgO ha⁻¹, and 400 kg CaO ha⁻¹), and the optimized fertilization regime with controlled-release fertilizers (D). The results showed that regime D performed best in terms of yield, nutrient-use efficiency, and EEB, which increased by 220.5% and 297.5% compared with regime A, and reduced the input cost by CNY 63,100~69,000 hm⁻². Moreover, compared with regime A, regimes B, C, and D significantly reduced the carbon, nitrogen, and phosphorus footprints, respectively, with the carbon footprint reduced by 6.7~21.7%, 72.4~74.8%, and 71.6~76.5%; the nitrogen footprint reduced by 2.6~19.0%, 80.7~82.2%, and 80.1~83.4%; and the phosphorus footprint reduced by 15.3%, 100%, and 100%. Furthermore, the comprehensive evaluation index (CEI) is D > C > B > A. In total, the three optimized regimes balanced high yield with environmental sustainability, with the D regime showing the best performance, offering scientific support for transitioning to low-carbon, high-value orchards in smallholder systems. Full article

The bioprocessing of agricultural wastes to produce microbial enzymes has become significant due to its benefits in reducing enzyme production costs and improving waste management. In this study, various substrates, including spent coffee grounds, coffee husks, coffee pulp, rice husks, rice bran, pomelo albedo, pomelo flavedo, orange peel, banana peel, sugarcane bagasse, and starch, were used as organic nutrient sources for α-amylase biosynthesis by B. licheniformis TKU004. Among the tested substrates, pomelo albedo (3%, w/v) was the most suitable carbon source for amylase production, with a productivity of 80.645 U/mL. The purification process resulted in a 60 kDa amylase. The protein identification of B. licheniformis TKU004 amylase revealed a coverage rate of 39% with α-amylase from Bacillus subtilis 168. B. licheniformis TKU004 amylase exhibited optimal activity at 60 °C and pH = 7 and showed a high compatibility with EDTA (Ethylenediaminetetraacetic acid). HPLC (high-performance liquid chromatography) analysis demonstrated that B. licheniformis TKU004 amylase is an α-amylase with the final products of maltobiose, maltose, and glucose. Due to its important properties, such as tolerance to EDTA, B. licheniformis TKU 004 amylase may be valuable for industrial applications, especially in detergents and food processing. Full article

Lemon, widely used in food, medicine, cosmetics, and other industries, has considerable value as a commodity and horticultural product. Previous research has shown that the fungus Diaporthe citri infects several citrus species, including mandarin, lemon, sweet orange, pomelo, and grapefruit, in China. Although D. citri has been reported to cause melanose disease in lemons in China, key pathological evidence, such as Koch’s postulates fulfillment on lemon fruits and detailed morphological characterization, is still lacking. In May 2018, fruits, leaves, and twigs were observed to be infected with melanose disease in lemon orchards in Chongqing municipality in China. The symptoms appeared as small black discrete spots on the surface of fruits, leaves, and twigs without obvious prominent and convex pustules. D. citri was isolated consistently from symptomatic organs and identified provisionally based on the morphological characteristics. The identification was confirmed using sequencing and multigene phylogenetic analysis of ITS, TUB, TEF, HIS, and CAL regions. Pathogenicity tests were performed using a conidium suspension, and melanose symptoms similar to those observed in the field were reproduced. To our knowledge, this study provides the first comprehensive evidence for D. citri as a causal agent of melanose disease in lemons in China, including morphological characterization and pathogenicity assays on lemon fruits. This report broadens the spectrum of hosts of D. citri in China and provides useful information for the management of melanose in lemons. Full article

In the “dual carbon” objective, the preparation of non-precious metal catalysts with low cost and high activity is essential for the study of hydrogen evolution reactions (HERs). This study employed biomass pomelo peel powder as the carbon source and ammonium metatungstate (AMT) as the tungsten source and, through a facile one-step method in molten salt, fabricated a biomass carbon-based nanocatalyst featuring carbon flakes adorned with tungsten carbide (WC) nanoparticles. Dicyandiamide and cysteine were introduced as nitrogen and sulfur sources, respectively, to explore the impacts of N-S elemental doping on the structure, composition, and HER performance of the WC/C catalyst. The experimental results showed that N-S doping changed the electronic structure of WC and increased the electrochemically active surface area, resulting in a significant increase in the HER activity of WC/C@N-S catalysts. The WC/C@N-S catalyst was evaluated with hydrogen evolution performance in a 0.5 mol/L H₂SO₄ solution. When the cathodic current density reached 10 mA/cm², the overpotential was 158 mV, and the Tafel slope was 68 mV/dec, underscoring its excellent HER performance. The outcomes offer novel insights into the high-value utilization of agricultural biomass resources, and pave the way for the development of cost-effective, innovative hydrogen evolution catalysts. Full article

The effects of pomelo peel-derived dietary fibers (total dietary fiber, cellulose, and microcrystalline cellulose) on in vitro simulated gastrointestinal digestion and fermentation characteristics of silver carp fish balls were systematically investigated. Our findings revealed that pomelo peel dietary fibers significantly enhanced protein digestibility (highest increased by 18.58%), free amino acid content (most elevated by 13.27%), and slow digestion starch content (highest increased by 64.97%) in fish balls, suggesting an improved nutritional quality of fish balls. Moreover, pomelo peel-derived dietary fibers increased the content of short-chain fatty acids in the digestive fish balls at the late stage of fermentation (48 h) and caused changes in gut microbiota with reducing the ratio of Firmicutes to Bacteroidetes (F/B), the abundance of Escherichia-Shigella and Streptococcus, and increasing the levels of probiotics Bacteroides and Phascolarctobacterium. These suggested that pomelo peel-derived dietary fibers could promote the digestive characteristics of fish balls, effectively exerting prebiotic effects by regulating gut microbiota. The results could provide a scientific basis for the enhanced modification of intestinal digestion and fermentation of fish balls with dietary fibers. Full article

Lignification of juice sacs is a primary contributor to reductions in fruit quality, with impacts on taste and economic value of pomelo (Citrus grandis). To date, information on the regulation of fruit lignification remains fragmentary. In this study, we first analyzed the relationship between lignification and nutrient status of pomelo juice sacs, which revealed a significant positive correlation between nitrate (NO₃⁻) concentration and lignin concentration, with over 60% of lignin accumulation explained by NO₃⁻ levels in three models of machine learning-based regression. Results from field trails in 11 pomelo orchards, as well as in pear fruits and soybean roots exposed to low or high NO₃⁻ supplies, further demonstrated that nitrate plays an important role in lignification. Transcriptomic analysis further showed that pomelo laccases (CgLACs) were more intensively up-regulated upon addition of NO₃⁻ than any of the genes encoding one of the other 12 enzymes involved in lignin biosynthesis. Among the nine identified CgLACs, CgLAC3 was the most significantly up-regulated CgLAC in high nitrate treated plants. Over-expressing CgLAC3 increased lignin concentrations in both pomelo albedo and soybean hairy roots. Taken together, we conclude that nitrate modulates fruit lignification in pomelo through regulation of CgLAC3 expression, which suggests that NO₃⁻-N fertilization may affect fruit lignification, and thereby can be managed to improve fruit quality. Full article

Citrus black spot (CBS), caused by the fungus Phyllosticta citricarpa, significantly affects citrus fruit marketability and can lead to premature fruit drop. Accurate and reliable detection of this quarantine pathogen is crucial, particularly for asymptomatic plant material. This study evaluated two qPCR assays, the EPPO recommended assay PC and assay Pc-TEF1, based on TEF region, for detecting P. citricarpa through a collaborative test performance study (TPS). DNA from the isolates of Phyllosticta spp. and other fungi was spiked into citrus fruit peel extracts (lemon, orange, and pomelo) and distributed among 13 laboratories. Sample and qPCR assay stability under typical transport conditions was confirmed, although prolonged storage affected Pc-TEF1 assay performance. The assays were assessed based on sensitivity, specificity, reproducibility, and repeatability. Both assays demonstrated high performance, with repeatability and reproducibility exceeding 95%. The PC assay, as expected, detected different related Phyllosticta species, while Pc-TEF1 showed higher specificity for P. citricarpa included in the TPS alone. Additionally, inhibitory effects were observed specifically in the pomelo peel samples, suggesting matrix-dependent variability. This TPS confirms that both PC and Pc-TEF1 qPCR assays are robust. Further evaluation of the qPCR assays would support the selection of the most reliable assays for the detection of P. citricarpa, contributing to the effective management of CBS disease in citrus production and trade. Full article

This study investigated the mechanical energy absorption properties of polymeric lattice structures fabricated using additive manufacturing. Existing studies have primarily focused on rigid or single-use materials, with limited attention given to flexible polymers and their behaviour under repeated compressive loading. Addressing this gap, the structures investigated in this study are manufactured using three flexible polymers—polyether block amide, thermoplastic polyurethane, and thermoplastic copolyester elastomer—to enhance the reusability performance. Two high-performance designs were analysed, namely honeycomb structures (inspired by pomelo peel and simply hexagonal arrangements) and 3D triply periodic minimal surface structure of the type FRD. The primary objective was to evaluate their energy absorption capacity and reusability using three repeated compression tests. These tests revealed that thermoplastic copolyester elastomer exhibited the highest energy absorption in initial impact conditions, but lower values for the following compressions. However, polyether block amide demonstrated superior reusability, maintaining a consistent energy absorption efficiency of 56.1% over multiple compression cycles. The study confirms that modifying triply periodic minimal surface structures along the z-axis enhances their absorption efficiency, with even-numbered z-parameter structures outperforming odd-numbered ones due to their complete cell structure. These findings highlight the critical role of structural geometry and material selection to optimise polymeric lattice structures for lightweight reusable energy absorption applications, such as automotive safety and impact protection. Full article

The valorization of citrus peel byproducts presents a sustainable and innovative approach to reducing food waste while improving the nutritional content of fruit-based products. Citrus peels, a significant byproduct of the fruit juice industry, are abundant in bioactive compounds with recognized health benefits and functional properties, making them particularly suitable for jam production. The global citrus industry generates substantial amounts of waste, with peels accounting for approximately 50% of the total fruit mass. Conventional disposal methods often result in environmental concerns and the underutilization of valuable bioresources. This study aims to investigate the potential of incorporating citrus peel into jam formulations as a means of enhancing their nutritional and functional properties. Jams were prepared using a traditional processing technique (TP) incorporating citrus peel. The experimental jam variants included pomelo peel jam (PPJ), lime peel jam (LiPJ), lemon peel jam (LePJ), clementine peel jam (CPJ), orange peel jam (OPJ), and grapefruit peel jam (GPJ). All jam samples were subjected to comprehensive analyses, including assessments of chemical composition, total soluble solids (TSSs), titrable acidity (g/100 g acid citric), macro- and microelement contents, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity using the FRAP assay. The study revealed high levels of biologically active compounds, such aspolyphenols, flavonoids, and vitamin C, in the jams, highlighting their antioxidant properties and potential health benefits. Among the jams, lemon peel jam (LePJ) exhibited the highest antioxidant activity and polyphenol content, making it a superior choice in terms of functional benefits. In terms of sensory analysis, orange peel jam (OPJ) was the most favored by consumers, demonstrating its high acceptability and potential for market success. Full article

Citrus is a globally consumed fruit with great popularity, yet systematic analyses of primary metabolites across major varieties remain scarce, with phenolic acids as an auxiliary focus due to their flavor relevance. In this study, the primary metabolites and phenolic acids of five citrus varieties were analyzed via liquid chromatography‒tandem mass spectrometry (LC–MS/MS). The analysis revealed that five different citrus varieties contained 342 primary metabolites and 77 phenolic acids. The PCA clearly distinguished the metabolites of various citrus varieties. Compared with the pomelo group, the lemon group presented the most differentially abundant metabolites, whereas the kumquat and navel orange groups presented the fewest. An examination of metabolic pathways with notable disparities revealed that phenylpropanoid biosynthesis and the biosynthesis of amino acids significantly varied between varieties. This study elucidates primary metabolic networks underlying citrus flavor diversification, with phenolic acids providing secondary modulation insights. Moreover, this study provides a theoretical foundation for enhancing the flavor of citrus fruits. Full article

Accurate quantification of the citrus dropped number plays a vital role in evaluating the disaster resistance capabilities of citrus varieties and selecting superior cultivars. However, research in this critical area remains notably insufficient. To bridge this gap, we conducted in-depth experiments using a custom dataset of 1200 citrus images and proposed a lightweight YOLO-MECD model that is built upon the YOLOv11s architecture. Firstly, the EMA attention mechanism was introduced as a replacement for the traditional C2PSA attention mechanism. This modification not only enhances feature extraction capabilities and detection accuracy for citrus fruits but also achieves a significant reduction in model parameters. Secondly, we implemented a CSPPC module based on partial convolution to replace the original C3K2 module, effectively reducing both parameter count and computational complexity while maintaining mAP values. At last, the MPDIoU loss function was employed, resulting in improved bounding box detection accuracy and accelerated model convergence. Notably, our research reveals that reducing convolution operations in the backbone architecture substantially enhances small object detection capabilities and significantly decreases model parameters, proving more effective than the addition of small object detection heads. The experimental results and comparative analysis with similar network models indicate that the YOLO-MECD model has achieved significant improvements in both detection performance and computational efficiency. This model demonstrates excellent comprehensive performance in citrus object detection tasks, with a precision (P) of 84.4%, a recall rate (R) of 73.3%, and an elevated mean average precision (mAP) of 81.6%. Compared to the baseline, YOLO-MECD has improved by 0.2, 4.1, and 3.9 percentage points in detection precision, recall rate, and mAP value, respectively. Furthermore, the number of model parameters has been substantially reduced from 9,413,574 in YOLOv11s to 2,297,334 (a decrease of 75.6%), and the model size has been compressed from 18.2 MB to 4.66 MB (a reduction of 74.4%). Moreover, YOLO-MECD also demonstrates superior performance against contemporary models, with mAP improvements of 3.8%, 3.2%, and 5.5% compared to YOLOv8s, YOLOv9s, and YOLOv10s, respectively. The model’s versatility is evidenced by its excellent detection performance across various citrus fruits, including pomelos and kumquats. These achievements establish YOLO-MECD as a robust technical foundation for advancing citrus fruit detection systems and the development of smart orchards. Full article

This study aimed to examine the effects of aluminum (Al) stress on the leaves of Shatian pomelo (Citrus maxima “Shatian Yu”) and its underlying response mechanisms. Leaf phenotype analysis, physiological response index determination, transcriptome analysis, and genome verification were employed to investigate the effects of Al toxicity in detail. Al toxicity stress inhibited leaf growth and development, reducing leaf area, girth, and both dry and fresh weights. Antioxidant enzyme activity and soluble protein content in leaves significantly increased with rising Al stress levels. Additionally, Al toxicity caused an accumulation of Al ions in leaves and a decline in boron, magnesium, calcium, manganese, and iron ion content. RNA sequencing identified 4868 differentially expressed genes (DEGs) under 0 mM (Control) and 4 mM (Al stress) conditions, with 1994 genes upregulated and 2874 downregulated, indicating a complex molecular regulatory response. These findings were further validated by real-time quantitative PCR (qPCR). The results provide critical insights into the molecular mechanisms of Shatian pomelo leaf response to Al toxicity and offer a theoretical basis and practical guidance for improving citrus productivity in acidic soils. Full article

Citri grandis Exocarpium (Chinese name Huajuhong, HJH) is a traditional Chinese medicinal herb widely used in traditional medicines and foods in China due to its efficacy in treating coughs and excessive phlegm. This study employed HS-SPME-GC-MS to analyze the volatile compounds in HJH samples from different regions, with the aim of distinguishing samples from Huazhou from those of other origins and exploring their potential relationship with ecological factors. A multidimensional strategy was utilized to analyze the relationships between volatile oils, climatic factors, and soil elements, examining how volatile compounds responded to ecological factors. From 47 batches of HJH samples across various regions, eight significantly different volatile compounds were identified, serving as chemical markers for HJH from Huazhou. The findings elucidate the impact of ecological factors on the volatile compounds of HJH, highlighting environmental factors relating to the authenticity of HJH from Huazhou. The results indicate that the authenticity of HJH is shaped by the unique climatic and soil environments of Huazhou. Full article