Longistylin A from Cajanus cajan (L.) Millsp. disturbs glycerophospholipid metabolism and cytokinin biosynthesis of Nocardia seriolae.

ETHNOPHARMACOLOGICAL RELEVANCE: Nocardiosis is an uncommon infectious disease that bears certain similarities to tuberculosis, with a continuous increase in its incidence and a poor prognosis. In traditional Chinese medicine, the leaves of Cajanus cajan (L.) Millsp. are employed to treat wounds, malaria, coughs, and abdominal pain. AIM OF THE STUDY: In this study, we investigated the effects and mechanisms of longistylin A (LGA), a natural stilbene isolated from C. cajan, as a potential antibiotic against nocardiosis. MATERIALS AND METHODS: LGA was isolated from the leaves of C. cajan and assessed using a minimum bactericidal concentration (MBC) determination against Nocardia seriolae. Multi-omics analysis encompassing genes, proteins, and metabolites was conducted to investigate the impact of LGA treatment on N. seriolae. Additionally, quantitative analysis of 40 cytokinins in N. seriolae mycelium was performed to assess the specific effects of LGA treatment on cytokinin levels. Cryo-scanning electron microscopy was utilized to examine morphological changes induced by LGA treatment, particularly in the presence of exogenous trans-zeatin-O-glucoside (tZOG). The therapeutic effect of LGA was investigated by feeding N. seriolae-infected largemouth bass. RESULTS: LGA exhibited significant efficacy against N. seriolae, with MBC value of 2.56 µg/mL. Multi-omics analysis revealed that LGA disrupted glycerophospholipid metabolism and hormone biosynthesis by notably reducing the expression of glycerol-3-phosphate dehydrogenase and calmodulin-like protein. Treatment with LGA markedly disrupted 12 distinct cytokinins in N. seriolae mycelium. Additionally, the addition of exogenous tZOG counteracted the inhibitory effects of LGA on filamentous growth, resulting in mycelial elongation and branching. Furthermore, LGA treatment improved the survival rate of largemouth bass infected with N. seriolae. CONCLUSIONS: We found for the first time that LGA from C. cajan exhibited significant efficacy against N. seriolae by interfering with glycerophospholipid metabolism and cytokinin biosynthesis.

Four new isocoumarins from Cajanus cajan.

Four novel new isocoumarins, cajanolactone B, C, D1 and D2 (1-4), were isolated from ethanolic extracts of the leaves of Cajanus cajan. The structural elucidation has been completed mainly depending on extensive spectroscopic analysis including UV, IR, NMR (1D and 2D), HRESIMS and chiral analysis. Notably, all these new isocoumarins were found to exist in racemic forms, among which compounds 3 and 4 share the same planar structure. This finding suggests that at least the biosynthesis of isocoumarin in C. cajan is chiral tolerant. A plausible biogenetic pathway of compounds 1-4 is proposed.

Three new anti-inflammatory stilbenoids and a diphenyl ether derivative from Cajanus cajan.

Three new stilbenoids, namely two rare plant-derived phenanthrenes denominated Cajananthrenes A and B (1, 2) and one bibenzyl named Cajanbenzyl (3), together with a diphenyl ether derivative designated Cajanether (4), as well as five other known compounds (5-9) were isolated from the ethanolic extract of the leaves of Cajanus cajan. Their structures were determined through extensive spectroscopic analysis including UV, IR, NMR (1D and 2D) and HRESIMS as well. A plausible biogenesis pathway was proposed for the biosynthesis of compounds 1-3. Compounds 1 and 2 displayed moderate anti-inflammatory activity as evident from the inhibitory effect on NO production in LPS-stimulated RAW 264.7 macrophages with IC50 values of 73.6 and 44.6 µM respectively.

Identification and in vitro Characterization of Novel Antidiabetic Peptides Released Enzymatically from Peanut Protein.

Bioactive peptides derived from proteins found in various foods provide significant health benefits, including regulating blood sugar levels by inhibiting carbohydrate-hydrolyzing enzymes. Hydrolysates of peanut protein were prepared using alcalase (AH) or trypsin (TH) to generate antidiabetic peptides with high activity against α-amylase (IC50 of 6.46 and 5.71 mg/mL) and α-glucosidase (IC50 of 6.30 and 5.57 mg/mL), as well as antiradical activity to scavenge DPPH• (IC50 of 4.18 and 3.12 mg/mL) and ABTS•+ (IC50 of 2.87 and 2.56 mg/mL), respectively. The bioactivities of hydrolysates were greatest in the ultrafiltration-generated F3 fraction (< 3 kDa). The most active fraction was TH-F3, which was purified by gel filtration chromatography to generate sub-fractions (SF). With IC50 values of 1.05 and 0.69 mg/mL, the F3-SF8 fraction was the most effective at inhibiting the activity of α-amylase and α-glucosidase, respectively. This fraction was further purified using RP-HPLC to generate sub-subfractions (SSF), the most active of which were F3-SF8-SSF9 and SSF10. The peptide sequences F3-SF8-SSF9 and SSF10 were determined using LC-MS/MS. Two novel antidiabetic peptides with the potential to inhibit α-amylase and α-glucosidase were identified, with the sequences Asp-Trp-Arg (476.22 Da, IC50 of 0.78, and 0.35 mg/mL) and Phe-Tyr (329.15 Da, IC50 of 0.91, and 0.41 mg/mL). These results suggest that peptides derived from peanut protein are attractive natural ingredients for diabetes management applications.

Pinostrobin from plants and propolis against human coronavirus HCoV-OC43 by modulating host AHR/CYP1A1 pathway and lipid metabolism.

Coronaviruses, as enveloped positive-strand RNA viruses, manipulate host lipid compositions to enable robust viral replication. Temporal modulation of the host lipid metabolism is a potential novel strategy against coronaviruses. Here, the dihydroxyflavone pinostrobin (PSB) was identified through bioassay that inhibited the increment of human coronavirus OC43 (HCoV-OC43) in human ileocecal colorectal adenocarcinoma cells. Lipid metabolomic studies showed that PSB interfered with linoleic acid and arachidonic acid metabolism pathways. PSB significantly decreased the level of 12, 13- epoxyoctadecenoic (12, 13-EpOME) and increased the level of prostaglandin E2. Interestingly, exogenous supplement of 12, 13-EpOME in HCoV-OC43-infected cells significantly stimulated HCoV-OC43 virus replication. Transcriptomic analyses showed that PSB is a negative modulator of aryl hydrocarbon receptor (AHR)/cytochrome P450 (CYP) 1A1signaling pathway and its antiviral effects can be counteracted by supplement of FICZ, a well-known AHR agonist. Integrative analyses of metabolomic and transcriptomic indicated that PSB could affect linoleic acid and arachidonic acid metabolism axis through AHR/CYP1A1 pathway. These results highlight the importance of the AHR/CYP1A1 pathway and lipid metabolism in the anti-coronavirus activity of the bioflavonoid PSB.

Inhibitory Mechanism of Pinosylvin Monomethyl Ether against Aspergillus flavus.

Control of Aspergillus flavus is beneficial for the agricultural economy and food safety. Stilbenes exhibit antifungal properties through an unknown mechanism. Here, six stilbenes isolated from Cajanus cajan were screened for anti-A. flavus activity. Among them, pinosylvin monomethyl ether (PME) showed the strongest anti-A. flavus activity and has a broad antifungal spectrum with negligible hemolysis within the concentration range measured. PME inhibited the spore germination of A. flavus and the accumulation of aflatoxin B1. Mechanistic studies showed that PME could bind the cell membrane phospholipids, resulting in increased permeability and decreased fluidity. Further metabolic analysis showed that PME caused the lysis of cell membranes and subsequent collapse of spores, which resulted in a cell wall autolysis-like phenotype. Structure-activity relationship analysis revealed the importance of maintaining amphiphilicity harmony by substituent groups for the antifungal activity of stilbenes. Together, natural stilbenes are promising antifungal lead compounds worthy of further exploration and research for potential application in the food, pharmaceutical, and agricultural industries.

Multi-target mechanisms against coronaviruses of constituents from Chinese Dagang Tea revealed by experimental and docking studies.

ETHNOPHARMACOLOGICAL RELEVANCE: The leaves of Eurya chinensis（Chinese Dagang Tea）have been consumed as herbal tea for centuries in Guangdong, China, and have also been used to prevent influenza and treat colds and fevers in traditional Chinese medicine. However, there are no reports on the chemical profile and efficacy of its leaves for the treatment of fever and viral infections. MATERIALS AND METHODS: The chemical constituents of Eurya chinensis leaves were isolated and identified by phytochemical study and spectroscopic data, E. chinensis extracts and compounds were evaluated for their antiviral activities by cytopathic effect (CPE) reduction and antibody-based EC50 assay. The antiviral effect of the main component was confirmed by immunofluorescence and transmission electron microscopy. Virtual screening and docking enzyme inhibition experiments were performed to analyze the anti-coronavirus mechanisms of the compounds from E. chinensis leaves. RESULTS: In this study, we found for the first time that E. chinensis leaf extract exhibited inhibitory effects against coronaviruses HCoV-OC43 in vitro. Among 23 monomer compounds isolated from E. chinensis leaf extract, the triterpenoids (betulinic acid, α-amyrin) and the flavonoids (naringenin, eriodictyol and quercetin) showed marked antiviral activity. Microscopic optical analyses further demonstrated that betulinic acid can remove virus particles from HCoV-OC43 infected cells. Virtual screening and docking analysis towards the coronavirus in vogue revealed that betulinic acid was able to bind well to PLpro and Nsp14N7-MTase, and that the flavonoids prefer to bind with PLpro, Nsp3MES, NspP14N7-MTase, Nsp16GTA, and Nsp16SAM. The enzyme inhibition experiments demonstrated that betulinic acid (1) exhibited significant inhibition of PLpro and N7-MTase activity of SARS-CoV-2. CONCLUSION: This study proposes E. chinensis and its triterpenoids and flavonoids as promising potential treatments for coronaviruses.

Next-generation sequencing of the mitochondrial genome of Bombus longipennis Friese, 1918 (Hymenoptera: Apidae).

Bombus longipennis is the species of Bumblebees (Hymenoptera: Apidae), which are important pollinators for wild plants and greenhouses crops. The complete mitochondrial genome (mitogenome) of B. longipennis was determined by next-generation sequencing. The mitogenome was 18,458 bp in size with 87.2% A + T content, containing 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and an AT-rich control region (D-loop). Gene arrangement was found to be identical to those of other mitogenomes of bumblebees (e.g. Bombus terrestris and Bombus ignitus). All 13 PCGs initiated with typical ATN codons. Among them, 11 PCGs terminated with TAA or TAG; only cox2 and nad4 have incomplete stop codon T. All 22 tRNAs can be folded into typical cloverleaf structure. Phylogenetic analysis based on the concatenated nucleotide sequences of all 13 PCGs indicated that B. longipennis was more closely related to other species of subgenus Bombus, which clustered into a monophyletic group.

The complete mitochondrial genome of Dudusa sphingiformis (Lepidoptera: Notodontidae) and phylogenetic analysis.

Dudusa sphingiformis is an important lepidopteran pest widely distributed in tropical and subtropical zones of Asia. In this paper, the complete mitochondrial genome (mitogenome) of D. sphingiformis was determined by next-generation sequencing. The mitogenome was 15,806 bp in length, comprising 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and an AT-rich control region (D-loop). The gene arrangement of this mitogenome was identical to that of the previous studies of Notodontidae moths. Almost all the PCGs initiated with typical ATN codons, except for cox1 with CGA. Among them, nine PCGs terminated with TAA or TAG, while other four PCGs (cox1, cox2, nad5, and nad4) with incomplete stop codon T. All the 22 tRNAs had the typical cloverleaf structure, except for trnS1, whose dihydrouridine (DHU) arm forms a simple loop. Phylogenetic analysis based on the concatenated nucleotide sequences of 13 PCGs indicated that D. sphingiformis was more closely related to other species of family Notodontidae, forming a monophyletic group, with well-resolved relationships among five family of Noctuoidea.

The complete mitochondrial genome of Bombus filchnerae (Hymenoptera: Apidae) and phylogenetic analysis.

Here, we report the complete mitochondrial genome (mitogenome) of Bombus filchnerae (Hymenoptera: Apidae). The genome size of B. filchnerae was 18,553 bp with 88.7% A + T content, containing 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and an AT-rich control region (D-loop). tRNA rearrangement was observed in this mitochondrial genome when compared to those of other bumblebee species (e.g. Bombus breviceps and Bombus asiaticus). All the 13 PCGs initiated with typical ATN codons. Among them, 11 PCGs terminated with TAA, only nad4 and nad5 with incomplete stop codon TA and T, respectively. All the 22 tRNAs can be folded into typical cloverleaf structure, except for trnS1, whose dihydrouridine (DHU) arm forms a simple loop. The phylogenetic analysis based on the concatenated nucleotide sequences of all 13 PCGs indicated that B. filchnerae showed the closest relationship with Bombus pascuorum, forming a mono clade of the subgenus Thoracobombus, with well-resolved relationships among nine Bombus subgenera.

The effect of dietary ginseng polysaccharide supplementation on porcine milk-derived esRNAs involved in the host immune responses.

Ginseng polysaccharides (GPS) have been well known as an immune modulator. This study was conducted to investigate the effects of dietary supplemental GPS on the immune responses involved in sow's milk-derived exosomal shuttle RNAs (esRNAs) using RNA-Seq and miRNA-Seq. Of the 213 identified miRNA types, a total of 26 conserved miRNAs were differently expressed in response to GPS supplementation, including 10 up-regulated and 16 down-regulated miRNAs in GPS feeding group. In addition, exosomal transcriptome analysis identified 14,696 protein-coding genes in sow's milk exosomes, and 283 genes with 204 and 79 candidates showing up and down-regulation were significantly responded to GPS supplementation. Integrated analysis of each differently expressed miRNA with significantly expressed genes further revealed the presence of 51 highly conserved miRNA-gene interactions that were annotated to be related to immunoregulatory functions. This work provided an important advance in the functional identification of dietary GPS supplementation and more fundamental information about how GPS promoted the immune response and healthy growth of the infant from mothers at molecular levels.