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In order to improve the yield of extracellular polysaccharide (EPS) by liquid fermentation of Pseudomonas fulva, using extracellular polysaccharide yield as an evaluation index, the EPS production conditions of the strain were optimized by single factor and response surface tests, and the antioxidant properties of the EPS were investigated. The results showed that the optimal conditions for the production of extracellular polysaccharides by P. fulva were maltose 44 g/L, soybean peptone 11 g/L, sodium dihydrogen phosphate 8 g/L, inoculum 4%, rotational speed 160 r/min, fermentation temperature 28 ℃, time 72 h, and initial pH 7.0. The yield of EPS under the optimal conditions was 4.56 g/L, which was 3.7 times that of before optimization. The results of antioxidant activities showed that EPS had good scavenging activity on DPPH radicals, ABTS radicals, hydroxyl radicals, and superoxide anion radicals in a certain concentration range. When the mass concentration of EPS was 2.5 mg/ml, the scavenging ability of EPS on DPPH radicals, ABTS radicals, hydroxyl radicals, and superoxide anion radicals was (70.83±1.80)%, (45.00±1.73)%, (65.83±1.80)%, and (44.6±2.11)%, respectively, which indicated that the EPS produced by the liquid fermentation of P. fulva had certain antioxidant activity.

Ginkgolic acid is a natural plant antifungal substance with important biological activities, present in the testa of Ginkgo biloba. This research aims to analyse the antifungal action of ginkgolic acid against pathogenic fungi. Ginkgolic acid was analyzed by HPLC and FTIR, and the in vitro inhibitory activities of ginkgolic acid against pathogenic fungi has been investigated. Results showed that ginkgolic acid was a small hydrophobic molecule composed of five ginkgolic acids and their derivatives, with the alkyl and phenolic hydroxyl groups being located on the skeleton of the aromatic ring. Among Nigrospora oryzae (N. oryzae), Alternaria alternata (A. alternata) and Penicillium expansum (P. expansum), ginkgolic acid showed the strongest inhibition against N. oryzae, and the inhibition rate of ginkgolic acid at 5 mg · mL-1 reached 65.82%. Ginkgolic acid lysed the cell membrane of N. oryzae, causing the leaking of the mycelial protein and enhancement of the permeability of the cell membrane, which caused the electrical conductivity of the liquid medium to increase. In addition, it also decreased the activities of superoxide dismutase and catalase in the mycelium of N. oryzae, thereby weakening the cell’s protective function by damaging the integrity of the biomembrane. Furthermore, ginkgolic acid can effectively protect the leaves of Epipremnum aureum from infection by N. oryzae. It was concluded that ginkgolic acid effectively inhibited the activity of N. oryzae.

Objectives Given the success of galanthamine in treating Alzheimer's disease, this study aims to establish an effective method to find drugs from Amaryllidaceae alkaloids and to clarify its mechanism in treating Alzheimer's disease. Methods The pharmacodynamic basis and mechanism of action between Amaryllidaceae alkaloids and Alzheimer's disease were explored by constructing a compound-target-disease network, targets protein-protein interaction, gene ontology, Kyoto Encyclopedia of Genes and Genomes pathway enrichment, and molecular docking verification. Key findings In total, a chemical library of 357 potential alkaloids was constructed. A total of 100 active alkaloid components were identified. Thirty-nine associated targets were yielded based on network construction, and the key targets were defined as HSP90AA1, ESR1, NOS3, PTGS2, and PPARG using protein–protein interaction network. Gene ontology items (490) and 68 Kyoto Encyclopedia of Genes and Genomes pathways were selected through the enrichment of target functions, including neuroactive ligand–receptor interaction, calcium signaling pathway, cAMP signaling pathway, Alzheimer disease, and serotonergic synapse that were related to Alzheimer's disease. Lastly, molecular docking demonstrated good stability in combining selected alkaloids with targets. Conclusions This study explained the mechanisms of Amaryllidaceae alkaloids in preventing and treating Alzheimer's disease and established a novel strategy to discover new drugs from biological chemical sources. [ABSTRACT FROM AUTHOR]

Priestia megaterium (P. megaterium PH3) is an endophytic bacterium isolated from peanuts. It has natural resveratrol production ability and shows potential application value. This study analyzed its genetic function and metabolic mechanism through whole-genome sequencing and found that the genome size is 5,960,365 bp, the GC content is 37.62%, and 6132 genes are annotated. Functional analysis showed that this strain contained 149 carbohydrate active enzyme genes, 7 secondary metabolite synthesis gene clusters, 509 virulence genes, and 273 drug-resistance genes. At the same time, this strain has the ability to regulate salt stress, low temperature, and hypoxia. Genomic analysis reveals a stilbene-synthase-containing type III polyketide synthase gene cluster that contributes to resveratrol synthesis. A safety assessment showed that the strain is non-hemolytic, does not produce amino acid decarboxylase, and is not resistant to multiple antibiotics. In the mouse model, P. megaterium PH3 did not have significant effects on body weight, behavior, or physiological indicators. These results provide important basic data and theoretical support for its industrial application and the research and development of plant protection agents. [ABSTRACT FROM AUTHOR]

Purpose: Psoriasis is not yet completely curable, and its etiology and pathogenesis are unclear. Necroptosis, also known as programmed necrosis, is a regulated mode of necrotic cell death. The interaction between inflammatory diseases and necrotic apoptosis has recently attracted significant attention. We explored the molecular mechanisms of necrotic apoptosis-related genes in psoriasis using bioinformatics methods to identify potential biomarkers for psoriasis. Patients and Methods: In this study, we screened psoriasis differentially expressed genes from the datasets GSE13355 and GSE14905 and took intersections with necrotic apoptosis-related genes for the next analysis. We used multiple machine learning algorithms to screen key genes and perform enrichment analysis. In addition, we performed an immune infiltration analysis. Transcription factors were predicted by the R package "RcisTarget". We also observed the cellular clustering of key genes in different cell types at the single-cell sequencing level. We used real-time fluorescence-based quantitative-polymerase chain reaction, Western blot, and immunohistochemistry to analyze gene expression in clinical samples. We constructed an imiquimod-induced psoriasis-like dermatitis model in mice for further validation. Results: Seven key genes were screened as follows: AIM2, CARD6, HPSE, MYD88, PYCARD, RAI14, and TNFSF10. Enrichment analysis showed that the key genes were mainly involved in inflammatory pathways. Immune infiltration analysis showed significantly higher levels of CD8 T cells, CD4 initial T cells, and CD4 memory-activated T cells in the disease group's samples than in the normal patients' samples. The key gene expression in single cells analyzed showed that PYCARD was significantly expressed in keratinocytes. PYCARD was selected for gene expression analysis; the results showed that its expression was significantly elevated in the skin lesion tissues of patients with psoriasis. We also verified that PYCARD might play a vital role in the development of psoriasis skin lesions using animal experiments. Conclusion: PYCARD plays a vital role in psoriasis development and is a potential biomarker for psoriasis. [ABSTRACT FROM AUTHOR]

Mung bean sprouts are widely consumed as a seasonal fresh vegetable, renowned for their affordability and richness in antioxidants and bioactive compounds. This study employed ultra‐high‐performance liquid chromatogram‐Q‐Exactive HF mass spectrometry (UHPLC‐QE‐MS) and multivariate statistical analysis to comprehensively evaluate the chemical profile of mung bean sprouts following sulfite immersion. The findings revealed a significant alteration in the overall chemical composition of mung bean sprouts following sodium sulfite immersion. Eleven components, including four sulfur‐containing compounds, were identified as characteristic markers distinguishing between non‐immersed and sodium sulfite‐immersed mung bean sprouts. Esterification and addition reactions were inferred to occur during sodium sulfite immersion, leading to the transformation of flavonoid and saponin sulfates. Commercial samples analysis indicated that sulfur‐containing compounds were detectable in 9 of 11 commercial mung bean sprouts. Meanwhile, when sodium sulfite concentration exceeded 3.00 mg/mL and immersion time exceeded 360 min, the contents of total polyphenol and flavonoid were significantly reduced and the antioxidant activity was adversely influenced. [ABSTRACT FROM AUTHOR]

Sprouts of black beans (Phaseolus vulgaris L.), soybeans (Glycine max L.) and mung beans (Vigna radiata L.) are widely consumed foods containing abundant nutrients with biological activities. They are commonly treated with sulphites for the preservation and extension of shelf-life. However, our previous investigation found that immersing the bean sprouts in sulphite might convert the active components into sulphur-containing derivatives, which can affect both the quality and safety of the sprouts. This study explores the use of FTIR in conjunction with chemometric techniques to differentiate between non-immersed (NI) and sodium sulphite immersed (SI) black bean, soybean and mung bean sprouts. A total of 168 batches of raw spectra were obtained from NI and SI-bean sprouts using FTIR spectroscopy. Four pre-processing techniques, three modelling assessment techniques and four model evaluation indices were examined for differences in performance. The results show that the multiplicative scatter correction is the most effective pre-processing method. Among the models, the accuracy rate of the three models was as follows: radial basis function neural network (95%) > convolutional neural network (91%) > random forest (82%). The overall findings indicate that FTIR spectroscopy, in conjunction with appropriate chemometric approaches, has a high potential for rapidly determining the difference between NI and SI-bean sprouts. [ABSTRACT FROM AUTHOR]

Seaweeds are a treasure trove of natural secondary metabolites. Terpenoids extracted from seaweeds are shown to possess a variety of antitumor cellular activities. However, due to the complex and diverse structures of terpenoids, their therapeutic targets and complex mechanisms of action have not been clarified. The present study summarises the research on terpenoids from seaweeds in oncological diseases over the last 20 years. Terpenoids show different degrees of inhibitory effects on different types of tumor cells, suggesting that terpenoids in seaweeds may have potential antitumor disease potential. Terpenoids with potential antitumor activity and their mechanism of action are investigated using network pharmacology. A total of 125 terpenoids and 286 targets are obtained. Proto‐oncogene tyrosine‐protein kinase Src(SRC), Signal transducer and activator of transcription 3 (STAT3), Mitogen‐activated protein kinase (MAPK3, MAPK1), Heat shock protein HSP 90‐alpha (HSP90AA1), Phosphatidylinositol‐4,5‐bisphosphate 3‐kinase catalytic subunit alpha (PIK3CA), and RAC‐alpha serine/threonine‐protein kinase (AKT1) are defined as core targets. According to GO function and Kyoto encyclopedia of genes and genomes(KEGG) enrichment analysis, terpenoids may affect the Phoshatidylinositol 3'‐kinase (PI3K)‐Akt signaling pathway, Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor resistance, Prostate cancer, MAPK signaling pathway, and Proteoglycans in cancer. In addition, the molecular docking results show that the selected terpenoids are all able to bind strongly to the active protein. Terpenoids may slow down the progression of cancer by controlling apoptosis, proliferation, and protein and enzyme binding. [ABSTRACT FROM AUTHOR]