The combined effect of diffuse radiation and leaf wetness on functional traits and transpiration efficiency on a cloud forest species.

Cloud forests are unique biomes that thrive in foggy environments for a substantial part of the season. Fog in cloud forests plays two critical roles: it reduces incoming radiation and creates a humid environment, leading to the wetting of the canopy. This paper aims to investigate the combined effect of both radiation and wetness on Myrica faya Wilbur-a cloud forest species present in subtropical regions-both directly in plants and through simulations. Experiments consisted of a controlled environment with two levels of radiation and leaf wetness: low radiation/wet conditions, and high radiation/no-wetness; and three treatments: continuous low radiation and wetness, continuous high radiation and no wetness and alternate high low radiation and alternate wetness. The results revealed that a combination of low radiation and leaf wetness significantly improves leaf stomata conductance and increases the specific leaf area (SLA). Changes in SLA were driven by leaf size changes. However, the minimum leaf conductance (gmin) did not respond to any of the treatments. The simulations focused on exploring the impact of radiation and canopy wetness on transpiration efficiency (TE), i.e. the ratio between photosynthesis (An) and transpiration (Tc). The simulations demonstrated that TE increased exponentially as the canopy was gradually wetted, regardless of the radiation environment. This increase in TE results from Tc approaching zero while An maintains positive values. Overall, this study provides an integrated understanding of how fog alters M. faya functioning and, potentially, other cloud forest tree species.

Modulation of rhizosphere microbial community and metabolites by bio-functionalized nanoscale silicon oxide alleviates cadmium-induced phytotoxicity in bayberry plants.

Cadmium (Cd) is an extremely toxic heavy metal that can originate from industrial activities and accumulate in agricultural soils. This study investigates the potential of biologically synthesized silicon oxide nanoparticles (Bio-SiNPs) in alleviating Cd toxicity in bayberry plants. Bio-SiNPs were synthesized using the bacterial strain Chryseobacterium sp. RTN3 and thoroughly characterized using advanced techniques. A pot experiment results demonstrated that Cd stress substantially reduced leaves biomass, photosynthesis efficiency, antioxidant enzyme activity, and induced oxidative damage in bayberry (Myrica rubra) plants. However, Bio-SiNPs application at 200 mg kg-1 significantly enhanced plant biomass, chlorophyll content (26.4 %), net photosynthetic rate (8.6 %), antioxidant enzyme levels, and mitigated reactive oxygen species production under Cd stress. Bio-SiNPs modulated key stress-related phytohormones by increasing salicylic acid (13.2 %) and abscisic acid (13.7 %) contents in plants. Bio-SiNPs augmented Si deposition on root surfaces, preserving normal ultrastructure in leaf cells. Additionally, 16S rRNA gene sequencing demonstrated that Bio-SiNPs treatment favorably reshaped structure and abundance of specific bacterial groups (Proteobacteria, Actinobacteriota, and Acidobacteriota) in the rhizosphere. Notably, Bio-SiNPs application significantly modulated the key metabolites (phenylacetaldehyde, glycitein, maslinic acid and methylmalonic acid) under both normal and Cd stress conditions. Overall, this study highlights that bio-nanoremediation using Bio-SiNPs enhances tolerance to Cd stress in bayberry plants by beneficially modulating biochemical, microbial, and metabolic attributes.

Ultrasonic synergistic slightly acidic electrolyzed water processing to improve postharvest storage quality of Chinese bayberry.

In the postharvest storage of Chinese bayberry, microbial loads and exogenous contaminants pose significant challenges, leading to rapid decay and deterioration in quality. This study introduced a synergistic approach, combining ultrasonics and slightly acidic electrolyzed water (US + SAEW), to enhance the postharvest storage quality of Chinese bayberry. This approach was benchmarked against conventional water washing (CW), standalone ultrasonic (US), and slightly acidic electrolyzed water (SAEW) processing. Notably, compared to CW, the US + SAEW method enhanced iprodione and procymidone removal rates by 69.62 % and 72.45 % respectively, improved dirt removal efficiency by 122.87 %, repelled drosophila melanogaster larvae by 58.33 %, and curtailed total bacterial, mold & yeast growth by 78.18 % and 83.09 %. Furthermore, it postponed the appearance of sample decay by 6 days, compared to 4 days for both US and SAEW alone. From a physicochemical perspective, compared to CW-treated samples, US + SAEW processing mitigated weight loss and color deviations, retained hardness, amplified the sugar-acid ratio, augmented activities of phenylalanine ammonia-lyase, superoxide dismutase, and catalase enzymes, suppressed polyphenol oxidase activity and malondialdehyde synthesis, and preserved total phenolic, anthocyanin, and antioxidant levels. These findings underscore the potential of US + SAEW as a strategic tool to preserve the quality of Chinese bayberry during postharvest storage.

Active colorimetric bilayer polycaprolactone-eucalyptus oil@silk fibroin-bayberry anthocyanins (PCL-EO@SF-BAs) membrane with directional water transport (DWT) for food packaging.

Currently, designing smart membranes with multifunctional effectiveness is crucial to food freshness monitoring and retention. Herein, an active colorimetric Janus bilayer membrane with directional water transport (DWT) performance is constructed by electrospinning, which comprises a hydrophilic layer of silk fibroin-bayberry anthocyanins (SF-BAs) and a hydrophobic layer of polycaprolactone-eucalyptus oil (PCL-EO). The entities of BAs and EO are well dispersed in the fiber matrix by hydrogen bonds and physical interactions, respectively. BAs endow the membrane colorimetric response and antioxidant activity, and EO contributes to the antibacterial activity while DWT performance is generated from the asymmetric wettability of the two layers. The bilayer membrane has an accumulative one-way transport index of 1077%, an overall moisture management capacity of 0.76 and a water evaporation rate of 0.48 g h-1. Moreover, the release of BAs and EO was predominantly controlled by Fickian diffusion. As a pH-sensing indicator, PCL-EO@SF-BAs is highly sensitive to external pH stimuli and the response is reversible. In addition to freshness monitoring, PCL-EO@SF-BAs can extend the shelf-life of pork beyond 100% at 4 °C. Also, it can extend the shelf life of shrimp by approximately 70% at 25 °C with the synergistic effect of antibacterial activity and the DWT performance.

Myricitrin from bayberry as a potential inhibitor of cathepsin-D: Prospects for squamous lung carcinoma prevention.

Cathepsin-D (CATD) inhibitors' design and development drawn interest due to their potential therapeutic applications in managing different cancer types, including lung cancer. This study investigated myricitrin, a flavonol-3-O-rhamnoside, for its binding affinity to CATD. Molecular docking experiments revealed a strong binding affinity (-7.8 kcal/mol). Molecular dynamics (MD) simulation confirmed the complex's stability, while enzyme activity studies showed inhibitory concentration (IC50) of 35.14 ± 6.08 µM (in cell-free) and 16.00 ± 3.48 µM (in cell-based) test systems. Expression analysis indicated downregulation of CATD with a fold change of 1.35. Myricitrin demonstrated antiproliferative effects on NCIH-520 cells [IC50: 64.11 µM in Sulphorhodamine B (SRB), 24.44 µM in 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)], but did not affect healthy CHANG cells. It also prolonged the G2/M phase (at 10 µM: 1.19-fold; at 100 µM: 1.13-fold) and increased sub-diploid population by 1.35-fold. Based on the analysis done using SwissADME program, it is predicted that myricitrin is not a cytochrome p450s (CYPs) inhibitor, followed the rule of Ghose and found not permeable to the blood-brain barrier (BBB) which suggests it as a safe molecule. In summary, the experimental findings may establish the foundation for myricitrin and its analogues to be used therapeutically in CATD-mediated lung cancer prevention.

Characteristic aroma improvement mechanisms of heat-sterilized bayberry juice regulated by exogenous polyphenols.

Bayberry juice is favored for its unique taste and flavor, while heat sterilization tends to reduce the aroma quality during processing, which limits its acceptability to consumers. To address this issue, we use exogenous polyphenols to regulate flavor compounds to improve the product quality. Total 13 differential key aroma-active compounds were identified between fresh bayberry juice (FBJ) and heat-sterilized bayberry juice (HBJ) using aroma extract dilution analysis (AEDA), orthogonal partial least squares-discriminant analysis (OPLS-DA) and odor activity values (OAVs). Further, eight polyphenols were added to investigate their influences on the aroma quality of HBJ respectively. The results showed that all tested polyphenols could maintain the aroma profile of HBJ closer to FBJ and improve the odor preference of HBJ, among which resveratrol and daidzein were most effective. Their aroma molecular regulatory mechanism involved enhancing the characteristic aroma of bayberry and reducing the certain off-flavored compounds produced by heat sterilization.

Ultrasonic assisted extraction of polyphenols from bayberry by deep eutectic supramolecular polymer and its application in bio-active film.

Ultrasound and deep eutectic supramolecular polymers (DESP) is a novel combination of green extraction method for phytochemicals. In this study, a new type of green extractant was developed: DESP. It is a derivative of deep eutectic solvent (DES) and was prepared by supramolecular polymer unit ß-cyclodextrin (ß-CD) as hydrogen bond acceptor (HBA) and organic acid as hydrogen bond donor (HBD). The current work focuses on the use of ultrasonic-assisted (UAE) DESP extraction of polyphenolic compounds (PCs) from bayberry. The experimental results showed that DESP synthesized with ß-CD and lactic acid (LA) in a ratio of 1:1 (w/w %) had the best extraction effect. And by using a three-level factor experiment and the response surface method, the predicted TPC content is very close to the actual content (28.85 ± 1.27 mg GAE/g). The DESP extract including PCs were further used as plasticizer for chitosan (CS) to prepare highly active green biofilms (DESP-CS). It is possible to reduce the tedious procedures for separating biologically active substances from DESP. The experiment proved that the prepared films have good mechanical properties, plastic deformation resistance, thermal stability and antioxidant activity.

Myrica esculenta Buch.-Ham. (ex D. Don): A Review on its Phytochemistry, Pharmacology and Nutritional Potential.

Myrica esculenta is an important ethnomedicinal plant used in the traditional system of medicine and as an important nutraceutical. Several studies on the plant justify its use in alternative systems of medicine and establish a scientific rationale for its possible therapeutic application. The plant contains a range of biologically active classes of compounds, particularly diarylheptanoids, flavonoids, terpenes, tannins, and glycosides. The nutraceutical potential of the plant can be particularly attributed to its fruit, and several studies have demonstrated the presence of carbohydrates, proteins, fats, fiber content, and minerals like sodium, potassium, calcium, manganese, iron, copper, and zinc, in it. The current review aims to provide complete insight into the phytochemistry, pharmacological potential, and nutritional potential of the plant, which would not only serve as a comprehensive source of information but also will highlight the scope of isolation and evaluation of these molecules for various disease conditions.

Macroalga-associated bacterial endophyte bioactive secondary metabolites twinning: Cystoseira myrica and its associated Catenococcus thiocycli QCm as a model.

Marine ecosystems represent the largest biome on the earth. Until now, the relationships between the marine microbial inhabitants and the macroalgal species unclear, and the previous studies are insufficient. So, more research is required to advance our understanding of macroalgal- microbial interactions. In this study, we tried to investigate the relationship between the brown marine macroalga, Cystoseira myrica and its associated bacterial endophyte, Catenococcus thiocycli, as the first study concerning the production of bioactive secondary metabolites from a macroalgal species comparing with its associated endophytic bacteria. Secondary metabolites were extracted from alga and its bacterial endophyte with ethyl acetate and methanol. All extracts contained significant quantities of phenolics, flavonoids, tannins, and saponins. Strikingly, extracts possess antioxidant, anti-inflammatory and antimicrobial activities which were significantly correlated to phenolic and flavonoid contents.

Flexible and easy-handling pristine polypyrrole membranes with bayberry-like vesicle structure for enhanced Cr(VI) removal from aqueous solution.

Polypyrrole has been extensively explored for Cr(VI) removal from wastewater towing to the advantages of superior performance, low cost, facile synthesis, and high environmental stability. However, the unsatisfactory adsorption capacity and complicated process of adsorbent separation from aqueous solutions remain a huge challenge, limiting its practical application. Herein, a flexible PPy membrane with bayberry-like vesicle structures (PPy-B) was prepared via template-assisted interfacial polymerization. It was found that sodium sulfosalicylate not only improved the flexibility and strength of the PPy-B membrane for easy-handling but also participated in the polymerization of PPy as a dopant to improve the specific surface area and doping level for increasing adsorption sites. Benefiting from these, the easy-handling PPy-B membrane exhibited a high adsorption capacity (586.90-682.50 mg/g at 298-318 K), a high reusability (five adsorption-desorption cycles), and a high ultimate adsorption capacity after adsorption-desorption cycles until membrane failure (1174.86 mg/g at 298 K). The proposed mechanisms of the enhanced Cr(VI) removal involve electrostatic adsorption, reduction, and ion exchange. This flexible PPy membrane therefore shows attractive advantages in wastewater treatment.

Myrica salicifolia Hochst. ex A. Rich. suppress acetic acid-induced ulcerative colitis in rats by reducing TNF-alpha and interleukin-6, oxidative stress parameters and improving mucosal protection.

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) with rising prevalence in developing countries, and limited success of current therapies, natural products have immense potential for therapy due to their "disease modifying and side-effect neutralizing" potential. Myrica salicifolia is traditionally used for gastrointestinal diseases and have reported antiinflammatory activities, but its use in IBD has not yet been studied. Therefore, in the present study, the effects of the root extract of M. salicifolia (Ms.Cr) were investigated using the acetic acid-induced UC model in rats. For 6 days, the rats were given either vehicle (10 mL/kg), lower (200 mg/kg), and higher (400 mg/kg) doses of Ms.Cr, or the positive control drug (prednisolone; 2 mg/kg) orally. A single dosage of 5% acetic acid (1.0 mL) was administered intrarectally to rats on day 6 to induce UC. Disease activity index (DAI), histological observations, the biochemical parameters related to oxidative stress, and specific cytokines such as interleukin-6 (IL-6) and the tumor necrosis factor-α (TNF-α) were determined to assess the effect of Ms.Cr. In comparison to the AA-induced colitis rats, Ms.Cr's pretreatment significantly decreased DAI, colonic ulceration, and inflammatory score. Total glutathione levels and catalase activity were considerably recovered in the colitis group treated with Ms.Cr, whereas enhanced lipid peroxidation in colon tissues was significantly decreased. Moreover, Ms.Cr pretreatment also caused inhibition of the activation of IL-6 and TNF-α in the colonic tissues of respective groups. Based on these findings, Ms.Cr might be developed to treat UC in the future.

Protective role of bayberry extract: associations with gut microbiota modulation and key metabolites.

Dysbiosis of the gut microbiota is inextricably intertwined with the onset and development of metabolic diseases. Dietary modulation of the gut microbiota has received much attention in recent years; however, currently there are still few effective approaches. Polyphenols extracted from fruits protect against metabolic disorders, and this effect is associated with the gut microbiota. We aimed to investigate the metabolic impact of bayberry extract cyanidin-3-O-glucoside and its associations with changes in the gut microbiota. Based on C57BL/6 and db/db mouse models, combined with 16S rRNA high-throughput sequencing and metabolomic profiling, we found that C3G administration reduced weight gain and fasting blood glucose levels. More importantly, C3G significantly modulated the gut microbiota including its composition, diversity and functional pathways. A distinct metabolite profile in addition to alterations of key metabolites was observed probably resulting from changes in the gut bacterial composition and metabolic pathways induced by C3G administration. This study may provide evidence for the missing link in mechanisms underlying the beneficial effects of poorly absorbed dietary polyphenols.

An overview of the nutritional value, health properties, and future challenges of Chinese bayberry.

Chinese bayberry (CB) is among the most popular and valuable fruits in China owing to its attractive color and unique sweet/sour taste. Recent studies have highlighted the nutritional value and health-related benefits of CB. CB has special biological characteristics of evergreen, special aroma, dioecious, nodulation, nitrogen fixation. Moreover, the fruits, leaves, and bark of CB plants harbor a number of bioactive compounds including proanthocyanidins, flavonoids, vitamin C, phenolic acids, and anthocyanins that have been linked to the anti-cancer, anti-oxidant, anti-inflammatory, anti-obesity, anti-diabetic, and neuroprotective properties and to the treatment of cardiovascular and cerebrovascular diseases. The CB fruits have been used to produce a range of products: beverages, foods, and washing supplies. Future CB-related product development is thus expected to further leverage the health-promoting potential of this valuable ecological resource. The present review provides an overview of the botanical characteristics, processing, nutritional value, health-related properties, and applications of CB in order to provide a foundation for further research and development.

Extraction and Study of Hypoglycemic Constituents from Myrica rubra Pomace.

Myrica rubra pomace accounts for 20% of the fruit's weight that is not utilized when it is juiced. The pomace contains bioactive phenolic substances such as anthocyanins and flavonoids. To improve the utilization value of Myrica rubra pomace, an optimized extraction method for the residual polyphenols was developed using response surface methodology (RSM). The resulting extract was analyzed by high performance liquid chromatography (HPLC), and the in vitro hypoglycemic activity and antioxidant activity of the polyphenolic compounds obtained were also investigated. The optimum extraction conditions (yielding 24.37 mg·g-1 total polyphenols content) were: extraction temperature 60 °C, ultrasonic power 270 W, ethanol concentration 53%, extraction time 57 min, and solid to liquid ratio 1:34. Four polyphenolic compounds were identified in the pomace extract by HPLC: myricitrin, cyanidin-O-glucoside, hyperoside, and quercitrin. DPPH and hydroxyl radical scavenging tests showed that the Myrica rubra polyphenols extract had strong antioxidant abilities. It is evident that the residual polyphenols present in Myrica rubra pomace have strong hypoglycemic activity and the juiced fruits can be further exploited for medicinal purposes.

Soil acidification induced decline disease of Myrica rubra: aluminum toxicity and bacterial community response analyses.

The decline disease of Myrica rubra tree is commonly induced by soil acidification, which affects the yield and the quality of fruits. It is hypothesized that aluminum toxicity and microbial community changes caused by soil acidification were the main causes of decline of Myrica rubra tree. In order to explore the decline mechanism of Myrica rubra tree, soils around healthy and decline trees of Myrica rubra were collected to compare the concentrations of different aluminum forms, enzyme activities, and bacterial community structure. In this study, soil samples were collected from the five main production areas of Myrica rubra, Eastern China. The results showed that diseased soils had higher exchangeable aluminum, lower enzyme activities, and lower microbial diversity than healthy soils at various sites. The toxic Al significantly decreased bacterial diversity and altered the bacterial community structure. The diseased soils had significantly lower α-diversity indices (ACE, Chao1, and Shannon) of bacterial community. The Al toxicity deceased the relative abundance of Acidobacteria and Planctomycetes, while enhanced the relative abundance of Cyanobacteria, Bacteroidetes, and Firmicutes in soils. Co-occurrence network analysis indicated that the Al toxicity simplified the bacterial network. The soil ExAl content was significantly and negatively correlated with the nodes (r = -0.69, p < 0.05) and edges (r = -0.77, p < 0.01) of the bacterial network. These results revealed that the Al toxicity altered soil bacterial community structure, resulting in the decline disease of Myrica rubra tree, while highlighted the role of Al forms in the plant growth. This finding is of considerable significance to the better management of acidification-induced soil degradation and the quality of fruits.

Assessment of Anti-inflammatory Activity of 3-Acetylmyricadiol in LPSStimulated Raw 264.7 Macrophages.

BACKGROUND: Pentacyclic triterpenoids are a biologically active class of phytoconstituents with diverse pharmacological activities, including anti-inflammatory action. OBJECTIVE: In the current study, we isolated 3-Acetylmyricadiol, a pentacyclic triterpenoid, from the ethyl acetate bark extract of Myrica esculenta and evaluated it for anti-inflammatory potential. METHODS: The ethyl acetate bark extract of the M. esculenta was subjected to column chromatography to isolate 3-Acetylmyricadiol. MTT assay was performed to check cell viability. The production of proinflammatory mediators like nitric oxide, IL-6, TNF-α were observed after the administration of 5, 10, 20 µM of 3-Acetylmyricadiol in LPS-activated raw 246.7 macrophages by the reported methods. RESULTS: MTT assay indicated more than 90% cell viability up to 20 µM of 3-Acetylmyricadiol. The administration of 3-Acetylmyricadiol inhibited the production of nitric oxide, IL-6, TNF-α in a dose-dependent manner significantly in comparison to LPS treated cells. The maximum effect was observed at 20 µM of 3-Acetylmyricadiol which resulted in 52.37, 63.10, and 55.37 % inhibition of nitric oxide, IL-6, and TNF-α, respectively. CONCLUSION: Our study demonstrated the anti-inflammatory action of 3-Acetylmyricadiol and can serve as a potential candidate in the development of the clinically efficient anti-inflammatory molecule.

Degradation of cyanidin-3-O-glucoside induced by antioxidant compounds in model Chinese bayberry wine: Kinetic studies and mechanisms.

The degradation kinetic of cyanidin-3-O-glucoside was determined in combination with different antioxidants, namely ascorbic acid, cysteine, reduced glutathione, and sodium sulfite at different concentrations and temperatures (4, 20, and 37 °C) in model Chinese bayberry wine. Ascorbic acid, cysteine, and reduced glutathione accelerated cyanidin-3-O-glucoside degradation; half-life times decreased by ca. 46 âˆ¼ 93%, 0.39 âˆ¼ 88%, and 1.6 âˆ¼ 92% respectively when the concentrations of antioxidants were 0.1 âˆ¼ 5 mM. Thiols with more -SH groups lead to faster degradation of cyanidin-3-O-glucoside. Interactions of oxidized cyanidin-3-O-glucoside with antioxidants were evaluated in aqueous solution and methanol to investigate the degradation mechanism of anthocyanin after oxidation. An anthocyanin-cysteine adduct was identified by LC-MS and formation pathways are proposed, along with mechanisms of anthocyanin degradation induced by antioxidants.

Simultaneous Extraction and Depolymerization of Condensed Tannins from Chinese Bayberry Leaves for Improved Bioavailability and Antioxidant Activity.

Biorefineries of polyphenols from plant leaves maximize their commercial value for developing biomedicines and nutrients. However, condensed tannins (CTs) constitute extensive polyphenols from plant leaves, which hinders the maximization due to extremely low bioavailability. Therefore, a simple, and sustainable one-step method was established to simultaneously extract polyphenols and depolymerize CTs with only endogenous flavan-3-ols from Chinese bayberry leaves via acid catalysis, which markedly improved the bioavailability of total polyphenols. Afterward, purification of polyphenols from depolymerized extract was studied with specific polymeric resins. Silica C18 showed the highest absorption efficiency of total polyphenols, while Amberlite XAD-7 and XAD-2 presented high selectivity toward polyphenols with high and low molecular weight, respectively. Combined depolymerization of CTs and purification with Amberlite XAD-2 showed the highest bioavailability and cellular free-radical scavenging activity of total polyphenols, which proved to be an ideal methodology for improving the bioavailability and activity of polyphenols from plant leaves.

Comparison of phytochemical profiles, antioxidant and antiproliferative activities in Chinese bayberry (Myrica rubra Sieb. et Zucc.) fruits.

Here, we examined the phytochemical profiles, antioxidant activity (AA), and antiproliferative activity (APA) of four Chinese bayberry (Myrica rubra Sieb. et Zucc.) pulp extracts. They were found to be rich in total phenolics content (TPC; 186.45 ± 5.42 to 498.94 ± 8.25 mg of gallic acid equiv./100 g FW) and total flavonoids content (TFC; 126.28 ± 4.18 to 194.35 ± 12.03 mg of catechin equiv./100 g FW). For all varieties, the free flavonoid/phenolic/anthocyanin contents were higher than that the bound fractions. Wild pink bayberry (WPB) displayed the highest values of TPC and TFC, and also showed the highest total antioxidant activity (TAA) as revealed by peroxyl radical scavenging capacity (PSC) (451.47 ± 8.01 µmol Vit. C equiv./100 g FW), and free cellular antioxidant activity (CAA) (184.99 ± 6.11 µmol quercetin equiv./100 g FW, no PBS wash; 117.78 ± 2.34 µmol quercetin equiv./100 g FW, PBS wash) assays. Bayberry extracts had a marked reduction in the APA of HepG2 cells, and WPB exhibited the lowest EC50 (8.50 ± 0.83 mg/ml) value, which was probably associated with cell cycle arrest and apoptosis induction. PRACTICAL APPLICATION: Chinese bayberry (Myrica rubra Sieb. et Zucc.) fruit is rich in natural phenolic compounds, which might be a functional ingredient in food and nutraceutical products. Our findings would provide a logical strategy to promote the comprehensive utilization of phenolics in bayberry fruit with both health and economy benefits.

[Simultaneous determination of 29 pesticides residues in bayberry by pass-through solid-phase extraction and ultra-performance liquid chromatography-high resolution mass spectrometry].

A rapid and accurate analysis method based on PRiME HLB pass-through solid-phase extraction (SPE) and ultra-performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) was developed for the determination of 29 pesticide residues in bayberry samples. The bayberry samples were first extracted using acetonitrile by vortexing; then, the extract solution was salted out and purified by PRiME HLB pass-through solid-phase extraction (SPE) cartridges. Chromatographic separation was subsequently carried out on a Waters ACQUITY UPLC HSS T3 column (100 mm×2.1 mm, 1.8 µm) using 5 mmol/L ammonium acetate in water and acetonitrile as the elution solvent. The electrospray ion source in positive (ESI+) mode and full mass-data-dependent MS2 (full mass-ddMS2) mode were used for quantification by the matrix-matched external standard method. The LC conditions were first optimized, and two analytical columns, Waters ACQUITY UPLC HSS T3 and Waters ACQUITY UPLC BEH C18, were investigated for the 29 pesticides. The results indicated that the Waters ACQUITY UPLC HSS T3 column showed better chromatographic retention. Moreover, composites of the mobile phase were also studied. Compared to the acetonitrile-formic acid aqueous solution system and acetonitrile-formic acid-ammonium acetate aqueous solution system, the acetonitrile-ammonium acetate aqueous solution system used as the mobile phase exhibited much better chromatographic behavior for most of the 29 pesticides. In particular, the MS responses of some of the target pesticides were significantly improved when using the ammonium acetate-acetonitrile system as the mobile phase. In addition, the sample pretreatment conditions for the 29 pesticides in bayberry samples were systematically optimized. The matrix effect (ME) for three different types of purification methods were applied to evaluate the purification efficiency for the 29 pesticides in the bayberry samples. The following results were obtained from the post-spiking experiments: (1) For graphitized carbon (GCB) SPE, the post-spiking recoveries of 29 pesticides in the bayberry samples were generally low, less than 60%. (2) For the QuEChERS method, the recoveries of most target pesticides improved. The pesticide ratio with recoveries ranging from 70% to 120% was found to be 41%; however, the pesticide ratio with recoveries of less than 60% was still high (35%). (3) For the PRiME HLB-based pretreatment method, the recoveries of the 29 pesticides obviously improved. The pesticide ratio with recoveries between 70% and 120% was up to 76%, while the pesticide ratios were only 14% and 10% for post-spiking recoveries of 60%-70% and >120%, respectively. Meanwhile, the recoveries of all 29 pesticides were found to be more than 60%. Therefore, the PRiME HLB-based method was better than the GCB SPE and QuEChERS methods for pretreatment of the 29 pesticides in the bayberry samples. In addition, the PRiME HLB-based pretreatment process does not require tedious operation processes such as activation, balance, and elution, and thus, the sample pretreatment time is greatly shortened. Under the optimal conditions, the 29 target pesticides showed good linearity in the range of 1.0-200.0 µg/L, with correlation coefficients (R2) higher than 0.999. The limits of detection (LODs) were 2.0 µg/kg for the 29 target pesticides. The recoveries of the pesticides spiked in the bayberry samples were in the range of 69.2%-135.6% at 6, 200, and 400 µg/kg, respectively, while the relative standard deviations (RSDs) in the range of 0.7%-14.6%. The proposed method based on PRiME HLB-pass through SPE-UPLC-HRMS was adopted to determine these 29 pesticides in 30 bayberry samples purchased from local and online markets. According to the results, pesticides such as methamidamine, difenoconazole, and tebuconazole were frequently detected in the bayberry samples. However, the maximum residue limits (MRLs) of methamidamine, difenoconazole, and tebuconazole in bayberry samples were not provided in GB 2763-2019. In summary, the developed method is fast, simple, sensitive, and accurate, and it can be applied for daily monitoring of pesticides in bayberry samples.