Amomum tsaoko is a medicinal and edible Zingiberaceae herb, while its stems and leaves are largely discarded and underutilized compared with its fruits. This study aimed to characterize the antibacterial active components of A. tsaoko stem and leaf ethyl acetate extract, clarify the antibacterial mechanism of core metabolite 5-indanol, and evaluate the application value of A. tsaoko stem-leaf by-products as green feed additives for Partridge Shank chickens. In vitro antibacterial assays combined with GC-MS metabolomics were performed on four Zingiberaceae species (A. tsaoko, Alpinia officinarum, A. villosum, A. oxyphylla); broth microdilution, time-kill curve, biofilm and cell membrane leakage tests were conducted to verify the bactericidal mode of 5-indanol. For the animal feeding trial, 30-day-old Partridge Shank chickens were randomly divided into five groups: control group (CK, basal diet), 0.05% A. tsaoko stem-leaf group (SL0.05), 0.10% stem-leaf group (SL0.10), 0.15% stem-leaf group (SL0.15), and positive control group supplemented with 0.10% A. tsaoko fruit (F0.10). Growth performance, meat quality, small intestinal morphology and cecal microbiota were systematically detected. The in vitro results revealed that ethyl acetate extract of A. tsaoko stems and leaves exhibited broad-spectrum antibacterial activity against Gram-positive and Gram-negative bacteria, with an MIC of 62.5 μg/mL against Staphylococcus aureus. Metabolomic screening identified 5-indanol as the dominant antibacterial marker compound, whose antibacterial efficacy was 20-fold higher than 2,3-dihydro-1H-indene-4-carbaldehyde. Mechanistically, 5-indanol disrupted bacterial membrane integrity, triggered leakage of intracellular biomacromolecules, suppressed biofilm formation and attenuated hemolytic virulence of S. aureus. In vivo data indicated that 0.10% dietary supplementation of A. tsaoko stems and leaves (SL0.10) achieved the optimal effect: Dietary supplementation with A. tsaoko significantly increased the average daily gain and reduced the feed conversion ratio of Partridge Shank chickens, with the most pronounced effect observed in the 0.10% stem-leaf group. The drip loss of breast and thigh muscle was decreased without adverse impacts on meat pH, color and tenderness. The villus height/crypt depth ratios of duodenum and ileum were elevated by 34.2% and 26.43%, respectively. Meanwhile, the relative abundances of beneficial phyla Firmicutes, Bacteroidetes and Ascomycota in gut microbiota were significantly enriched, and the alpha diversity of bacterial and fungal communities was improved. Collectively, 5-indanol is the key antibacterial component in the ethyl acetate extract of A. tsaoko. Waste stems and leaves of A. tsaoko can be developed as novel antibiotic-free phytogenic feed additives, which realizes full-plant high-value utilization of A. tsaoko agricultural by-products and provides theoretical support for sustainable green livestock breeding.

Environmental factors play a crucial role in regulating the accumulation of secondary metabolites in medicinal plants, which ultimately determines their pharmacological quality. Amomum tsao-ko is commonly used as spice and medicinal ingredient in China, known for its essential oil enriched with flavor compounds that serve as a critical quality indicator. However, the yield and quality of A. tsao-ko are commonly constrained by specific habitat requirements. While previous studies have mainly focused on the chemical constituents and bioactivities of the essential oils, the ecological factors influencing their quality variation remain insufficiently explored. This study utilized an integrated multi-omics approach to investigate how soil environment and rhizosphere microbial communities correlate with the accumulation of flavor compounds in A. tsao-ko fruits across different altitudes. Our finding revealed that the accumulation patterns of geraniol and geranyl acetate were opposite to those of citrals and bicyclononane aldehydes, with the former two compounds showing a significant increase with rising altitude. Additionally, the accumulation of geraniol and geranyl acetate was positively correlated with the levels of available nitrogen, iron (Fe), and zinc (Zn) in the soil. In contrast, the contents of citral and bicyclononane aldehydes were significantly positively associated with Pseudomonas and nitrogen-fixing bacterial taxa such as Zophobihabitans and Rhizobium. Furthermore, although terpenoid biosynthesis-related genes exhibited significant variation across altitudinal environments, their expression levels showed relatively weak correlations with soil environmental changes. Overall, our study reveals correlations with soil nutrients and rhizosphere soil microbial ecology in shaping the biosynthesis and accumulation of characteristic terpenoids in A. tsao-ko, which may impact fruit quality. These findings might provide valuable insights for optimizing fertilization practices and targeted rhizosphere microbial management to improve the quality of A. tsao-ko fruit.

【Objective】This study aimed to investigate the effects of various mulching films on agronomic traits, yield, economic value, and volatile metabolites of flue-cured tobacco variety 'Yueyan 97', providing theoretical basis for the precise selection of mulching films in Nanxiong tobacco-growing areas.【Method】The dominant flue-cured tobacco cultivar 'Yueyan 97' widely cultivated in Guangdong tobacco-growing regions was used as the experimental material. Four mulching film treatments were established, including black-transparent film (BW, transparent in the middle with black edges), fully transparent film (W), silver-transparent film (YGW, transparent in the middle with silver edges), and pure silver film (YG). The application effects were comprehensively evaluated by measuring agronomic traits at maturity, grading yield and value, and analyzing volatile components in tobacco leaves.【Result】In terms of agronomic traits, plant height of the W treatment was significantly higher than that of YG, and the maximum leaf length in the BW treatment was significantly lower than YG. There were no significant differences in the number of effective leaves and maximum leaf width among the four mulch treatments. The YG treatment possessed the optimal position of the maximum leaf and the most uniform population growth. In terms of yield and output value, YG had the highest proportion of upper leaves, yield and output value, while treatment W presented the worst comprehensive production performance. A total of 89 volatile compounds from eight chemical groups were identified by GC-MS. The range of relative content of esters was 16.630%, which was affected most obviously by mulch types, whereas alkenes showed the weakest response. Principal component analysis (PCA) demonstrated that YG and W shared similar metabolic profiles, while BW and YGW formed separate clusters. The contents of core aroma substances including esters, trans, trans-farnesol and α-ionone in BW tobacco leaves were significantly higher than those of other treatments, with the lowest concentration of harmful myosmine. Geraniol also reached the highest level under BW treatment, with no significant difference compared with the YGW treatment. Treatment YG accumulated high levels of alcohols and dihydroactinidiolide, but its characteristic aroma components were relatively low and the myosmine content was higher. The W and YGW treatments had certain advantages in ketone accumulation without prominent comprehensive performance.【Conclusion】Comprehensively considering agronomic performance, economic output and aroma quality, BW treatment slightly reduced the maximum leaf length but significantly elevated the contents of aroma compounds and decreased harmful components in tobacco leaves, making it the optimal mulch film for high-quality flue-cured tobacco production in Nanxiong tobacco-growing areas. The YG mulch film is suitable for tobacco cultivation targeting stable plant growth and high accumulation of alcohol compounds, while W and YGW treatments show no obvious comprehensive advantages.

Purslane (Portulaca oleracea L.) is an important plant species that has been increasingly used in functional gene studies and molecular analyses. However, reference genes that exhibit stable expression across multiple tissues and stress conditions have not been systematically validated in purslane, which limits the accuracy of reverse transcription quantitative PCR (RT-qPCR) based gene expression analyses. In this study, ten candidate reference genes from six gene families (Actin, PP2A, CYP, eIF4A, Ubiquitin, and eIF5A) were selected based on transcriptome data. A combination of bioinformatic analyses and experimental validation was employed to comprehensively characterize these candidates, including their physicochemical properties, chromosomal localization, phylogenetic relationships, gene structures, and promoter cis-acting elements. Furthermore, the expression stability of the candidate genes was systematically evaluated across different tissues (seed, root, stem, leaf, and flower) and under multiple stress treatments, including salinity, temperature stress, drought, and hormone treatments. Based on conventional PCR amplification specificity, melting curve analysis, Ct value distribution, and amplification efficiency, ACT-2 and eIF5A-1 were identified as the most stably expressed reference genes under diverse experimental conditions. This study provides reliable reference gene candidates for accurate normalization of gene expression in purslane and establishes a systematic framework for reference gene selection in non-model plant species.

Purslane is a valuable medicinal and edible plant with broad environmental adaptability, resulting in extensive germplasm diversity worldwide. This genetic diversity manifests not only in morphological traits but also in varying levels of resistance to aphid infestation. In this study, we conducted a field survey of aphid populations on 99 purslane accessions and performed controlled inoculation experiments to identify two accessions with extreme differences in aphid resistance: accession no. 66 (HS, highly susceptible) and accession no. 119 (HR, highly resistant). Behavioral assays revealed that aphids preferred feeding on the HS accession and exhibited higher reproduction rates. Comparative transcriptome analysis between the two accessions revealed significant enrichment of genes involved in the monoterpenoid biosynthesis pathway. Non-targeted metabolomic profiling further demonstrated that the levels of two monoterpenoid compounds, d-limonene and myrcene, differed significantly between the HS and HR accessions. Integrated transcriptomic and metabolomic analyses identified two terpene synthase (TPS) genes, PolA01G018740 and PolB01G006810, whose expression levels were strongly correlated with the differential accumulation of d-limonene and myrcene. The differential expression of these TPS genes probably underlies variations in monoterpene content that contribute to aphid deterrence. Our findings provide molecular and biochemical insights into the mechanisms of aphid resistance in purslane and identify candidate genes for breeding insect-resistant cultivars.

Protoplast-based transformation is a vital tool for genetic studies in fungi, yet no protoplast method existed for P. sclerotiorum-scaumcx01 before this study. Here, we optimized protoplast isolation, regeneration, and transformation efficiency. The highest protoplast yield (6.72 × 106 cells/mL) was obtained from liquid mycelium after 12 h of enzymatic digestion at 28 °C using Lysing Enzymes, Yatalase, cellulase, and pectinase. Among osmotic stabilizers, 1 M MgSO4 yielded the most viable protoplasts. Regeneration occurred via direct mycelial outgrowth and new protoplast formation, with a 1.02% regeneration rate. PEG-mediated transformation with a hygromycin resistance gene and GFP tagging resulted in stable GFP expression in fungal spores and mycelium over five generations. LC/MS-based metabolomic analysis revealed significant changes in glycerophospholipid metabolism, indicating lipid-related dynamics influenced by GFP tagging. Microscopy confirmed successful colonization of tomato roots by GFP-tagged scaumcx01, with GFP fluorescence observed in cortical tissues. Enzymatic (cellulase) seed pretreatment enhanced fungal colonization by modifying root surface properties, promoting plant–fungal interaction. This study establishes an efficient protoplast transformation system, reveals the metabolic impacts of genetic modifications, and demonstrates the potential of enzymatic seed treatment for enhancing plant–fungal interactions.

Bacillus subtilis demonstrates functional diversity through production of structurally distinct lipopeptides, demonstrating significant potential for biocontrol applications. Two high-yield lipopeptide-producing strains, SL-2(7216.4 mg/L) and L6(3462.2 mg/L), were isolated from oil-contaminated soil. Their lipopeptide composition, antifungal activity, and genomic features related to secondary metabolite synthesis were systematically analyzed. Both strains predominantly produced surfactin and fengycin, with SL-2 showing higher proportions of long-chain components. Crude lipopeptide extracts from both strains strongly inhibited 5 typical plant pathogenic fungi (Botrytis cinerea, Alternaria tenuissima, Fusarium redolens, Pythium spinosum and Rhizoctonia solani), while SL-2 additionally suppressed 3 phytopathogenic fungi (Colletotrichum capsici, Fusarium solani and Mucor parvisporus). Genomic analysis revealed SL-2 (4.11 Mbp) and L6 (4.36 Mbp) harbor 14 and 11 secondary metabolite gene clusters, respectively. SL-2 exhibited enriched genetic pathways for quorum sensing, two-component systems, and ABC transporters. SL-2 contains a more complete biosynthetic Nis operon for lanthipeptide class I which is crucial for the production of mature antimicrobial peptides by Gram-positive bacteria and the production and transport of the antifungal substance subtilin. SL-2 also contains the unique gene blpAB related to ABC-type bacteriocin/lantibiotic exporters, which is involved in bacteriocin production and transport. Lipopeptideproducing bacterium Bacillus subtilis and its genomics research not only provide genomic data and research direction for further excavation of strain function and genetic engineering modification, but also provide broadspectrum, high-yielding strain resources with industrial fermentation and commercial prospects for the development of bacterial agents in the field of agricultural biological control.

China is currently the leading producer and consumer of rice globally, and soil quality has a decisive impact on rice growth, including metabolite accumulation and plant disease resistance. Despite the importance of these interactions, limited research exists on the relationship between rhizosphere microorganisms and secondary metabolite profiles across different rice cultivars. To address this gap, 16s rRNA and ITS sequencing and metabolomics were used to investigate the changes in rhizosphere microorganisms and root metabolism in different rice cultivars under dryland conditions. The results showed that rice dry farming can improve soil quality by improving soil chemical properties and soil enzyme activities and increasing beneficial soil microorganisms. Compared to SLHN, the organic carbon content notably increased under dry farming, with YHSM exhibiting the highest rise at 182.90%. Soil urease (S-UE) and acid phosphatase (S-ACP) activities in YNSM also increased significantly by 116.90 and 19.65%, respectively. Additionally, rice drought farming can also increase the content of root metabolites and improve rice drought resistance. These findings offer valuable insights into the mechanism of rice under drought conditions.

Drought is currently one of the biggest challenges facing global agricultural production. Purslane (Portulaca oleracea L.) has attracted widespread attention due to its exceptional drought resistance. However, the dynamics in endophytic bacterial communities and their synergistic response mechanisms with metabolites under drought stress in purslane remain poorly understood. The study systematically investigated the dynamic responses of endophytic bacterial communities and metabolites in purslane under drought stress and rehydration conditions through integrating 16 S rDNA sequencing and untargeted metabolomics. Results revealed that drought stress caused no significant changes in purslane’s endophytic bacterial community, whereas rehydration induced a marked restructuring of the microbiota. Co-expression network analysis identified Delftia and Stenotrophomonas were the key hub species in the drought and rehydration groups, respectively. Untargeted metabolomic analysis detected a total of 2,973 metabolites, primarily lipids, lipid-like molecules, and organic acids and their derivatives, which were significantly enriched in pathways such as phenylalanine biosynthesis, amino acid metabolism, and tyrosine metabolism. Integrated random forest modeling and Spearman correlation analysis revealed significant associations between differential bacterial genera and differential metabolites, with Stenotrophomonas showing particularly close links to multiple metabolites. Drought stress did not significantly change the endophytic bacterial community structure in purslane, while rehydration increased diversity and altered the dominant genera. Metabolite levels also shifted significantly under different water conditions. Strong links were found between endophytic bacteria and these metabolic changes. Together, these findings offer new insights into how microbial-metabolite interactions help purslane adapt to water stress.

In this study, we present MagnoliidsGDB, an integrated functional genomics database specifically developed for magnoliids, a group of plants known for their unique characteristics and medicinal properties. As of March 2024, MagnoliidsGDB has collected 31 genome sequences from 24 species, 149 resequencing datastes from 4 species, 842 transcriptomic datasets from 20 species, and metabolomic data from 15 species. This comprehensive resource allows researchers to explore the genomic, transcriptomic, and metabolomic variations of magnoliids. The user-friendly search and analysis functionalities of MagnoliidsGDB facilitate the study of genomic variations, gene functions, plant evolution and key metabolites of magnoliids. We hope this database will contribute to the study of magnoliids and increase our understanding of the origin, variation, and molecular basis of the unique biological features of magnoliids. ### Competing Interest Statement The authors have declared no competing interest.

The filamentous fungus Penicillium sclerotiorum is significant in the ecological and industrial domains due to its vast supply of secondary metabolites that have a diverse array of biological functions. We have gathered the metabolic potential and biological activities associated with P. sclerotiorum metabolites of various structures, based on extensive research of the latest literature. The review incorporated literature spanning from 2000 to 2023, drawing from reputable databases including Google Scholar, ScienceDirect, Scopus, PubMed, among others. Ranging from azaphilones, meroterpenoids, polyketides, and peptides group exhibits fascinating potential pharmacological activities such as antimicrobial, anti-inflammatory, and antitumor effects, holding promise in pharmaceutical and industrial sectors. Additionally, P. sclerotiorum showcases biotechnological potential through the production of enzymes like β-xylosidases, ß-D-Glucosidase and xylanases, pivotal in various industrial processes. This review underscores the need for further exploration into its genetic foundations and cultivation conditions to optimize the yield of valuable compounds and enzymes, highlighting the unexplored potential of Penicillium sclerotiorum in diverse applications across industries.

In recent years, avocado branch blight has gradually become one of the major diseases causing mortality of avocado trees, which seriously affects the economic development of avocado planting regions. In order to investigate the cause of the disease, the pathogens were isolated from the interroot of avocado trees with the onset of the disease and identified as Lasiodiplodia theobromae. At the same time, three Bacillus velezensis strains, YK194, YK201, and YK268, with better antagonistic effects and high stability against L. theobromae, were isolated from the rhizospheric soil of healthy avocado plants. The results of branch experiments and field trials showed that the avocado leaves as well as branches treated with the strains YK194, YK201, and YK268 did not develop disease, and the incidence of avocado trees was significantly reduced. In the branch experiments, the biological control effect of the strains YK194, YK201, and YK268 reached 62.07, 52.70, and 72.45%, respectively. In the field experiments, it reached 63.85, 63.43, and 73.86%, respectively, which indicated that all these three strains possessed good biological control effects on avocado branch blight. Further investigation on the mechanism of action of antagonistic strains revealed that B. velezensis YK268 could produce lipopeptides, namely, surfactin, fengycin, and iturin, which could significantly inhibit the spore germination of L. theobromae. Consequently, these three isolates have potential as biocontrol agents against L. theobromae.

Mikania micrantha, one of the world’s most destructive invasive species, is known for causing significant ecological and economic harm. While extensive research has focused on its growth characteristics, secondary metabolites, and control measures, its chemical interactions with the environment—particularly the role of flavonoids in shaping soil microbial communities—remain underexplored. In this study, we identified and quantified ten flavonoids from M. micrantha root exudates using UPLC-MS, including Hispidulin, Isorhamnetin, and Mikanin. To examine their impact, crude flavonoid extracts were applied to soil in potted experiments, which demonstrated that these compounds significantly increased soil fungal diversity and boosted the relative abundance of arbuscular mycorrhizal fungi (AMF). Furthermore, KEGG pathway analysis revealed that flavonoid addition elevated the copy numbers of genes involved in nitrogen cycling and metabolic functions, enhancing nutrient availability and microbial activity. Additionally, crude flavonoid extracts promoted the relative abundance of beneficial soil bacteria, such as Achromobacter, as well as AMF, both of which contribute to nutrient acquisition, plant growth, and soil health. These findings indicate that M. micrantha’s flavonoids can alter soil microbial community composition, thereby creating a favorable environment that reinforces its competitive edge over native plants.

Purslane (Portulaca oleracea L.) is highly valued for its nutritional, medicinal, and ecological significance. Genetic transformation in plants provides a powerful tool for gene manipulation, allowing for the investigation of important phenotypes and agronomic traits at the genetic level. To develop an effective genetic transformation method for purslane, various organ tissues were used as explants for callus induction and shoot regeneration. Leaf tissue exhibited the highest dedifferentiation and regeneration ability, making it the optimal explant for tissue culture. By culturing on Murashige and Skoog (MS) medium supplemented with varying concentrations of 6-benzyleaminopurine (6-BA) and 1-naphthaleneacetic acid (NAA), somatic cells from leaf explants could be developed into calli, shoots, and roots. The shoot induction results of 27 different purslane accessions elucidated the impact of genotype on somatic-cell regeneration capacity and further confirmed the effectiveness of the culture medium in promoting shoot regeneration. On this basis, a total of 17 transgenic plants were obtained utilizing the genetic transformation method mediated by Agrobacterium. The assessment of GUS staining, hygromycin selection, and polymerase chain reaction (PCR) amplification of the transgenic plants as well as their progeny lines indicated that the method established could effectively introduce foreign DNA into the purslane nucleus genome, and that integration was found to be stably inherited by offspring plants. Overall, the present study demonstrates the feasibility and reliability of the Agrobacterium-mediated genetic transformation method for introducing and integrating foreign DNA into the purslane genome, paving the way for further research and applications in purslane genetic modification.

Amomum tsao-ko Crevost et Lemarie (Zingiberaceae), an aromatic plant, has been considered to have diverse medicinal values and economic significance. It has been reported to possess antibacterial, antioxidant, and antidiabetic effects. With the increasing risk of diseases in aquaculture, there is a need for alternative solutions to chemical antibiotics. Plant extracts have shown promise as natural feed additives for aquatic animals. In this study, the antibacterial effect of Amomum tsao-ko crude extracts was evaluated using the Oxford cup method. The extracts exhibited significant antimicrobial activity against Salmonella typhimurium and Salmonella enteritidis. Furthermore, the addition of Amomum tsao-ko to fish feed resulted in notable changes in the gut structure of zebrafish and tilapia. The length and morphology of intestinal villi were enhanced, promoting improved digestion. Analysis of the gut microbial community revealed that Amomum tsao-ko supplementation induced key changes in the gut microbial community composition of both zebrafish and tilapia. Notably, a 1% inclusion of Amomum tsao-ko resulted in a marked rise in Proteobacteria levels in zebrafish, which diminished at 10% dosage. The supplement elicited mixed reactions among other bacterial phyla like Actinobacteria and Verrucomicrobiota. Fluctuations were also observed at the genus level, pointing to the concentration of Amomum tsao-ko playing a pivotal role in influencing the structure of intestinal bacteria. The findings of this study suggest that Amomum tsao-ko has antibacterial properties and can positively influence the gut health of fish. The potential use of Amomum tsao-ko as a natural feed additive holds promise for improving aquaculture practices and reducing reliance on chemical antibiotics. Further research is needed to explore the full potential and applications of Amomum tsao-ko in fish feed development.

Many naturally occurring chemical metabolites with significant cytotoxic activities have been isolated from medicinal plants and have become the leading hotspot of anti-cancer research in recent years. Hyptis rhomboidea Mart. et Gal is used as a folk medicine in South China to treat or assist in the treatment of liver disease, ulcers, and edema. But its chemical constituents have not been fully investigated yet. This study aimed to assess the cytotoxicity of H. rhomboidea, which was chemically characterized by chromatography–mass spectrometry methods. The results showed that the 95% ethanol extract of H. rhomboidea has marked inhibitory effects on five human cancer cell lines (HL-60, A549, SMMC-7721, MDA-MB-231, and SW480), with IC50 values ranging from 15.8 to 40.0 μg/mL. A total of 64 compounds were identified by ultra-high-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) and gas chromatograph–mass spectroscopy (GC-MS) analysis of H. rhomboidea crude extract. Among them, kaempferol, quercetin, rosmarinic acid, squalene, and campesterol were found to be abundant and might be the major metabolites involved to its bioactivity. The cytotoxic characterization and metabolite profiling of H. rhomboidea displayed in this research provides scientific evidence to support its use as medicinal properties.

Amomum tsao-ko is an important spice and medicinal plant that has received extensive attention in recent years for its high content of bioactive constituents with the potential for food additives and drug development. Diarylheptanoids are major and characteristic compounds in A. tsao-ko; however, the biochemical and molecular foundation of diarylheptanoids in fruit is unknown. We performed comparative metabolomics and transcriptomics studies in the ripening stages of A. tsao-ko fruit. The chemical constituents of fruit vary in different harvest periods, and the diarylheptanoids have a trend to decrease or increase with fruit development. GO enrichment analysis revealed that plant hormone signaling pathways including the ethylene-activated signaling pathway, salicylic acid, jasmonic acid, abscisic acid, and response to hydrogen peroxide were associated with fruit ripening. The biosynthetic pathways including phenylpropanoid, flavonoids, and diarylheptanoids biosynthesis were displayed in high enrichment levels in ripening fruit. The molecular networking and phytochemistry investigation of A. tsao-ko fruit has isolated and identified 10 diarylheptanoids including three new compounds. The candidate genes related to diarylheptanoids were obtained by coexpression network analysis and phylogenetic analysis. Two key genes have been verified to biosynthesize linear diarylheptanoids. This integrative approach provides gene regulation and networking associated with the biosynthesis of characteristic diarylheptanoids, which can be used to improve the quality of A. tsao-ko as food and medicine.

为了解药用植物大叶藤黄(Garcinia xanthochymus)叶片的化学成分,采用UPLC-QTOF-MS从叶片中得到19个化合物,主要为双黄酮类、黄酮类和间苯三酚类化合物.采用色谱分离法从叶片的 80％甲醇提取物中分离得到 5 个单体化合物,根据理化性质及波谱数据,分别鉴定为二氢山奈酚(1)、dulcisbiflavonoid A(2)、7-去甲基银杏双黄酮(3)、mono-[2-(4-carboxy-phenoxycarbonyl)-vinyl]ester(4)、山奈酚(5).化合物1 和 2 为首次从大叶藤黄中分离得到,化合物3 和4 为首次从藤黄属植物中分离得到.化合物1 和5 清除DPPH自由基的IC50值分别为146.8和39.0 μg/mL,表明其具有抗氧化活性.

目的 研究低温压榨、高温压榨和超声波辅助溶剂提取3种不同制油工艺对酸木瓜籽油提取率、成分及氧化稳定性的影响.方法 利用气相色谱-质谱法(gas chromatography-mass spectrometry,GC-MS)对木瓜籽油脂肪酸组成和挥发性成分进行分析;采用schaal烘箱法加速氧化,以酸价和过氧化值为指标对木瓜籽油氧化稳定性进行评估.结果 超声波辅助溶剂提取法出油率最高,其中不同溶剂提取以二氯甲烷最佳,出油率达44.21％;不同制油工艺对酸木瓜籽油脂肪酸组成影响很小,共鉴定出7种脂肪酸,相对含量最高的是油酸,其次是亚油酸、棕榈酸、硬脂酸,其中不饱和脂肪酸占比可达80.35％;在酸木瓜籽油中鉴定出47种挥发物,以烷烃类为主,溶剂法与压榨法制取的木瓜籽油挥发物组成差异较大,其中以2,4-二叔丁基苯酚和反式角鲨烯为首,溶剂法制得的油中2,4-二叔丁基苯酚占比为23.94％,反式角鲨烯占比为4.14％,而由低/高温榨取法制得的油中2,4-二叔丁基苯酚占比分别为3.20％和2.77％,反式角鲨烯占比分别为29.15％和23.38％;低温压榨制油清除1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基效果最好;超声波辅助溶剂制油在烘箱实验中酸价和过氧化值变化最小,氧化稳定性最好.结论 从食用和皮肤外用等角度看,低温压榨法安全性较高且能最大程度地保留酸木瓜籽油的营养成分,若从其他利用角度来看,超声波辅助溶剂提取法出油率最高且氧化稳定性最好,通过对比不同提取方法对酸木瓜籽油成分及氧化稳定性的影响,以期为酸木瓜籽油的开发及利用提供理论参考.

For decades chlorine dioxide has been used in water disinfection with excellent results. As the scope of application expands, chlorine dioxide has the potential for soil disinfection. We used amplicon sequencing and gas chromatography-mass spectrometry to compare the changes of four mixed rhizosphere microbial community samples and 12 tobacco leaf volatile samples four months after the flood irrigation with chlorine dioxide in different concentrations (0, 2, 4, 8 mg/l). Phenotypic data of 60 tobacco plants were also collected. The effects of chlorine dioxide on rhizosphere microorganisms were positively correlated with dose gradients. Bacteria responded more strongly in both community structure and metabolic pathways than fungi. Five new bacterial phyla (Firmicutes, Bacteroidota, Myxococcota, Patescibacteria, Verrucomicroboata) appeared in chlorine dioxide treatment groups, while the fungal community only appeared as one new fungal phylum (Basidomycota). Alterations in 271 predicted metabolic bacterial pathways were found. However, in the fungal community were only 10 alternations. The correlations between leaf volatile compounds and rhizosphere microorganisms under the influence of chlorine dioxide treatment could be observed based on network results. However, natural connectivity had already been declining rapidly when less than 20% of the network's nodes were removed. Therefore, the microbe-metabolite network is not stable. It might be why chlorine dioxide treatments did not significantly affect tobacco quality (p = 0.754) and phenotype (p = 0.867). As a comprehensive investigation of chlorine dioxide in agriculture, this study proves the effectiveness and safety of chlorine dioxide soil disinfection and widens the application range of chlorine dioxide.