Search Results (1,385)

Background/Objectives: Probiotic interventions are widely used to improve intestinal health; however, comparative evidence on multi-strain formulations with different potencies, particularly when combined with plant-based complexes, remains limited. This study evaluated the effects of two probiotic blends containing phytonutrients: PBP1, comprising Lacticaseibacillus strains, and PBP2, comprising Lacticaseibacillus, Lactobacillus, and Bifidobacterium strains. The effects on bowel function, microbial metabolites, and gut barrier-related markers were investigated. Methods: In this randomized, double-blind, placebo-controlled trial, participants received PBP1, PBP2, or placebo for 8 weeks. Stool patterns (7-day Bristol Stool Form Scale (BSFS) diary), fecal short-chain fatty acids (SCFAs), tryptophan metabolites, zonulin, and gut microbiota were assessed at baseline and Week 8. Efficacy was evaluated by comparing each intervention group with the placebo group. Results: Both PBP1 and PBP2 significantly increased the proportion of normal stool types (BSFS types 3–5) compared with placebo (p < 0.05). Fecal SCFA levels, including acetate, propionate, and butyrate, were significantly increased in both intervention groups. Notably, butyrate levels were significantly elevated compared with placebo. Fecal tryptophan levels decreased, while indole metabolites showed increasing trends, with an inverse correlation observed between tryptophan and indole, particularly in the PBP2 group. Fecal zonulin showed a decreasing trend, with significant reductions in participants with 25.0 ≤ BMI < 30.0 kg/m². Microbiome analysis revealed preserved alpha diversity with selective compositional shifts, including enrichment of Lactobacillus-related taxa. Conclusions: Supplementation with PBP1 and PBP2 improved bowel function and was associated with changes in microbiome-derived metabolites, including SCFAs and tryptophan–indole metabolism, with BMI-dependent changes in barrier markers. These findings suggest a potential role of microbiome-mediated metabolic modulation in intestinal health. Full article

N-acetylserotonin methyltransferase (ASMT) is among the key enzymes involved in the final steps of melatonin biosynthesis. Here, we have shown that inactivation of ASMT in A. thaliana results in reduced endogenous melatonin levels, modulating other plant hormone pathways and affecting stress-related responses. Transcriptomic analysis of the asmt-null mutant revealed that the differentially expressed genes were predominantly enriched in terms associated with auxin responses and signalling, as well as with abscisic acid (ABA)-mediated stress responses. In addition, the expression of genes involved in the ethylene, salicylic acid, jasmonic acid and brassinosteroid pathways was altered in the mutant. Assays of a β-glucuronidase (GUS) construct in which a fragment containing 1000 bp upstream of the ASMT start codon was fused to the GUS reporter gene confirmed that ASMT is involved in the responses to ABA, gibberellic and indole acetic acids, trans-zeatin, ethylene and epibrassinolide, which is consistent with the results of the in silico analysis of the ASMT promoter. Furthermore, the expression of a number of genes, such as SLG1, HIS1-3, AtAIRP1 and several LEA genes, whose transcriptional regulation is associated with water management and contributes to impaired tolerance to dehydration stress, was altered in the mutant. The pleiotropic effects of ASMT gene disruption facilitate the identification of new potential melatonin targets and provide insights into the specific mechanisms of melatonin action. Full article

The aim of this study is to develop and comprehensively evaluate the efficacy of an innovative formulation of a biological preparation consisting of a bacterial consortium (Serratia proteamaculans B5, Pseudomonas putida D7 and Lysinibacillus sp. S1), embedded in a pullulan polysaccharide matrix, as an agent for inducing systemic resistance in barley (Hordeum vulgare L.) to phytopathogenic stress caused by Fusarium graminearum. To optimize the product’s protective efficacy and minimize the pesticide load on the agroecosystem, a reduced dose of Fundazol (50% of the standard rate) was incorporated into the formulation. The constituent strains exhibited high indole-3-acetic acid production (53.29–69.2 μg·mL⁻¹) and strong antagonistic activity against phytopathogenic fungi, with inhibition zones reaching up to 32.5 mm. Pot and field trials were conducted to comprehensively assess the effect of the biological product on the stress tolerance of barley plants. Pre-sowing seed treatment reduced proline accumulation (by up to 2.3-fold), maintained photosynthetic pigment levels, and increased field germination to 79%. Under infectious field conditions, treatment with the biopreparation contributed to the stabilization of yield structure parameters (treated plants exhibited increases in height and biomass of 9–21%) and the improvement of grain quality indicators. Overall, the results obtained demonstrate the potential of the developed biopreparation as a component of comprehensive protection strategies and as an inducer of plant priming mechanisms. Full article

Cacti thrive in arid and coastal environments partly through associations with beneficial endophytic and rhizosphere bacteria; however, current knowledge remains limited. This study aimed to assess the diversity of cultivable bacteria associated with Opuntia dillenii and evaluate their potential as Plant Growth-Promoting (PGP) agents. Endophytic bacteria were isolated from cladodes and roots, while rhizobacteria were recovered from rhizosphere soil. Bacterial isolates were identified using morphological characteristics and 16S rRNA/gyrB sequencing, followed by screening for PGP traits, pH and temperature tolerance. A total of 31 isolates were obtained, including 23 endophytes and 8 rhizobacteria, mainly affiliated with Firmicutes, Actinobacteria, and Proteobacteria. Bacillus (35.48%) and Priestia (32.25%) predominated, with Priestia flexa as the most prevalent species. The most frequent PGP traits were phosphate solubilization (80.65%), proteolytic activity (70.97%), siderophore production (67.74%), and nitrogenase activity (64.52%). The highest phosphate solubilization indices were observed for strain R3 (3.41), R6 (3.39) and S6 (3.21), whilst the highest indole-3-acetic acid yields were recorded for C9 (172.88 µg/mL), R11 (96.22 µg/mL) and C3 (90.94 µg/mL), and the strongest siderophore production for C3 (30.37 mm), C7 (27.96 mm) and S7 (27.88 mm). These findings highlight O. dillenii-associated coastal bacteria as promising resources for plant growth and plant stress resilience. Full article

Silver maple is a fast-growing, adaptable tree that often frequents wet places and thus can play an important ecological role in replanting schemes. For this, robust, high-quality seedlings are essential. In other tree species, improved seedling quality has been achieved by treating with a combination of humic substances (HSs) and bacterial strains capable of synthesizing auxin phytohormone; the benefit being attributed, without clear supporting evidence, to changes in phytohormone concentrations in the plant. To clarify the uncertainty, we conducted assays of hormones in silver maple seedlings treated with HSs and appropriate bacteria. We hypothesized that any positive additive effects between HSs and bacteria may be due to the ability of HSs to bind phytohormones. This hypothesis was tested and confirmed by using optical absorption spectra of auxins, humic acids, and their combination, as well as by modeling their interactions. The combination of humic substances and bacteria resulted in an approximately 1.5-fold increase in auxin content in roots, accompanied by a marked increase in root weight and length. We suggest this is likely the outcome of HSs binding to bacterial auxins and delivering them to plant roots. Concentrations of cytokinins and abscisic acid also changed under these treatments, which may help explain observed increases in photosynthesis and improved water balance. Full article

Baikal skullcap (Scutellaria baicalensis) is one of the most important herbs used for centuries in traditional Chinese medicine. The main objective of the research was to micropropagate and introduce the most vigorous lines into garden cultivation. Eleven lines representing individual genotypes were selected and propagated using nodal segments. 6-Benzylaminopurine (BAP) at 1.0 mg L⁻¹, alone or with indole-3-acetic acid (IAA) at 0.1 mg L⁻¹, was the most effective for shoot regeneration. Significant variability in multiplication rate (2.5–6.4 shoots per explant) was observed among the lines. Shoots were successfully rooted (97.9%) and then acclimatized. After six months of cultivation, 113 well-developed plants representing all genotypes were obtained. Depending on the genotype, the final survival rates ranged from 26.9 to 80.0%. Flow cytometry (FCM-DAPI) analysis confirmed the ploidy stability of the micropropagated plants and ISSR markers revealed notable variability among the lines. Moreover, a polymorphism level of 36.4% was detected within line SB_6, whereas the other two analyzed lines (SB_3 and SB_7) maintained in vitro for four years showed no somaclonal variation. Therefore, genetic stability must be monitored, particularly in long-term cultures. In subsequent studies, the acclimatized lines will be evaluated for root yield and phytochemical content under garden conditions. Full article

Colorectal cancer (CRC) is intricately linked to gut microbiota dysbiosis and tryptophan (Trp) metabolic dysregulation. This study aimed to clarify the role and mechanisms of 20(S/R)-ginsenoside Rh1 in suppressing colorectal cancer through the regulation of gut microbiota and Trp metabolism. Azoxymethane/dextran sulfate sodium (AOM/DSS)was employed to induce a CRC mouse model, followed by treatment with 20(S/R)-ginsenoside Rh1 at 100 mg·kg⁻¹·day⁻¹ for 6 weeks. 20(S/R)-ginsenoside Rh1 significantly reduced the disease activity index (DAI) score, restored colon length, and decreased tumor count. 20(S/R)-Ginsenoside Rh1 ameliorated gut dysbiosis by increasing gut microbial diversity and elevating the prevalence of beneficial bacteria, including Lactobacillus, and stimulated the production of indole derivatives, including indole-3-propionic acid (IPA), indole-3-acetic acid (IAA), and indole-3-lactic acid (ILA) by enriching Trp -metabolizing bacteria such as Lactobacillus reuteri. These changes further activated the AhR/CYP1A1/IL-22 and PXR/TLR4 pathways, upregulated the expression of intestinal tight junction proteins, suppressed the secretion of proinflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and IFN-γ, and elevated the levels of the anti-inflammatory cytokine IL-10. Furthermore, 20(S/R)-ginsenoside Rh1 reduces the serum kynurenine (Kyn)/Trp ratio, downregulates the expression of forkhead box P3 (FoxP3), a marker of regulatory T (Treg) cells, and increases the number of CD8⁺ T cells by inhibiting the expression of indoleamine 2,3-dioxygenase 1 (IDO1) in colonic tissue. In conclusion, 20(S/R)-ginsenoside Rh1 showed potential anti-CRC activity, with our study observing links between its action and gut microbiota structure regulation, Trp metabolism modulation, AhR/PXR-mediated intestinal barrier activation, and IDO1-related immune suppression reversal. Full article

Nutgall tree anthracnose, caused primarily by Colletotrichum species, acts as a primary bottleneck restricting the sustainable development of the Rhus chinensis industry. Developing green biocontrol strategies by screening molecular targets for novel fungicides is highly imperative. A strain designated as Serratia plymuthica WF63 was isolated from healthy R. chinensis tissues. The strain exhibited broad-spectrum antifungal activity and multiple plant growth-promoting (PGP) traits, including the production of protease, cellulase, and indole-3-acetic acid (IAA). In vivo experiments revealed that S. plymuthica strain WF63 achieved a biocontrol efficacy of over 50% against anthracnose pathogens (Colletotrichum nymphaeae and C. fioriniae) and demonstrated significant plant growth-promoting effects. Gas chromatography–mass spectrometry (GC-MS) analysis, combined with in vitro toxicity validation of pure compounds, identified hexahydro-2H-pyrido [1,2-a]pyrazin-3(4H)-one as a core antifungal component in the fermentation broth, with a half maximal effective concentration $\left(E{C}_{50}\right)$ of 133.88 mg·L⁻¹ against the target pathogen. These findings not only highlight S. plymuthica strain WF63 as a promising antifungal biological agent but also suggest that the specific nitrogen-containing heterocyclic compound may serve as a candidate scaffold for further fungicide optimization, pending comprehensive ecotoxicological evaluation. Full article

The scaffold protein RACK1 (Receptor for Activated C Kinase 1) integrates signaling and translation, acting as a core component of the 40S ribosomal subunit. It binds activated Protein Kinase C (PKC) isoforms and membrane receptors. We used an auxin-inducible degron (AID2) system in human HAP1 cells to selectively deplete the free (cytoplasmic) pool of RACK1. The engineered RACK1–mAID–mClover3 fusion was rapidly degraded in the cytoplasm upon addition of 5-phenyl-indole-3-acetic acid (5-Ph-IAA), while the ribosome-bound pool remained detectable in ribosomal fractions, indicating that ribosome association makes RACK1 relatively less accessible to AID2-mediated proteolysis. Upon activation of PKCβII with phorbol-12-myristate-13-acetate (PMA), imaging at defined time points revealed closely matched kinetics of PKCβII membrane recruitment and membrane-proximal enrichment of ribosome-bound RACK1, peaking at ~10 min. Our data support a model in which activated PKCβII engages ribosome-bound RACK1 at membrane-proximal sites, consistent with a diffusion–capture mechanism in which PKCβII first accumulates at the membrane and then captures ribosome-bound RACK1, thereby recruiting the translational machinery to sites of signal input for membrane-proximal translation. These findings provide new insights into the spatial organization of translation. Full article

Tomato is susceptible to various fungal pathogens, including Alternaria alternata and Curvularia spicifera, which can cause extensive post-harvest losses. Chemical fungicides have limited effectiveness in controlling post-harvest fungal pathogens and pose risk to human health and the environment. Therefore, this study assessed indigenous isolates of three species of Trichoderma (Tr1: T. longibrachiatum; Tr2: T. harzianum; and Tr3: T. asperellum) as biocontrol agents against two fungal pathogens in vitro and in vivo and determined their physicochemical analysis and plant-growth-promoting traits. The three species of Trichoderma exhibited catalase production in vitro, while T. longibrachiatum and T. asperellum showed the highest potential for plant-growth promotion by producing indole-3-acetic acid and phosphate solubilization but not nitrogen-fixing capability. T. harzianum showed lower potential in these traits. Mycelial growth was found to be maximum (5.77–12.27 cm) at 30 °C and a pH of 7–9, but inhibition (2.60–5.13 cm) was recorded at the highest temperature (45 °C) and pH (11). In vivo, studies on tomato fruits indicated that T. longibrachiatum and T. asperellum significantly (p < 0.05) reduced lesion diameters of A. alternata by 53.60% and 48.71%, respectively, and C. spicifera by 55.58% and 56.19%, respectively, relative to the infected control. Besides their antifungal efficacy, the three species of Trichoderma enhanced tomato seedling growth, particularly at 1/10 filtrate dilution, and improved fruit quality parameters by increasing firmness and nitrate content, while reducing oxidative stress. Physicochemical analysis indicated that Trichoderma-treated fruits had better firmness, pH, and nitrate value coupled with a reduction in oxidative stress (reduced malondialdehyde content) compared to pathogen-infected controls. The indigenous isolates of the three species of Trichoderma provided high efficacy as biocontrol agents of the two fungal pathogens that cause post-harvest losses of tomato, suggesting that biological control can replace synthetic chemicals in preserving tomato under storage conditions and contribute to agricultural sustainability. Full article

High temperature during flowering and grain filling severely reduces rice yield and grain quality. Split potassium (K) fertilization can mitigate such heat-induced damage, yet its mechanisms linking grain filling, endogenous hormones and grain performance remain unclear. Here, a two-year pot experiment was conducted to explore the effects of split K application on rice yield, quality and hormonal metabolism under high temperature. Four treatments included ambient temperature with full basal K (AT-K₁₀₀), high temperature with full basal K (HT-K₁₀₀), and two split K regimes under high temperature (HT-K₇₀₊₃₀, HT-K₃₀₊₇₀). Split K application decreased abscisic acid (ABA) levels at 5 days after anthesis (DAA), increased indole-3-acetic acid (IAA), zeatin riboside (ZR) and gibberellin A3 (GA₃) at 5 DAA, and maintained higher IAA and GA₃ levels until 20 DAA. The ratios of ABA/IAA and ABA/GA₃ were also reduced at both 5 and 20 DAA. These hormonal alterations optimized grain-filling dynamics, prolonged active filling duration and improved middle- and late-stage filling rates, thereby promoting grain weight accumulation and suppressing chalkiness formation. Compared with HT-K₁₀₀, HT-K₇₀₊₃₀ increased yield by 8.75%, which was attributed to improved seed-setting rate and 1000-grain weight. HT-K₃₀₊₇₀ enhanced spikelet number per panicle, seed-setting rate and 1000-grain weight, but significantly decreased effective panicles, resulting in no obvious yield advantage. Furthermore, split K application effectively reduced grain chalkiness, with a more pronounced effect at a higher panicle-stage K proportion. Under ongoing global warming, K management can be tailored to production goals: higher basal K is preferable for yield pursuit, while increasing panicle K topdressing effectively improves grain quality. Full article

In this study, nine strains of plant growth-promoting rhizobacteria (PGPR) with multiple growth-promoting functions were isolated and screened from the rhizosphere of plants (Phragmites communis, Triglochin maritimum, and Alhagi maurorum) in the arid and barren regions of Western China. These strains belong to five genera: Klebsiella, Bacillus, Serratia, Pseudomonas, and Flavobacterium. The growth-promoting characteristics of these nine strains (PAP4, PA35, AC12, ACP1, AC25, TP7, TP8, TP12, and TP14) were analyzed. Furthermore, the growth-promoting potential of these PGPR strains was comprehensively evaluated through plate and pot experiments using Arabidopsis thaliana and alfalfa. The results indicate that most strains possess the ability to fix nitrogen and secrete zeatin and extracellular polysaccharides (EPS). Some strains exhibited significant traits such as phosphate solubilization, siderophore secretion, and the production of 1-aminocyclopropane-1-carboxylate (ACC) deaminase and indole-3-acetic acid (IAA). All strains showed high salt tolerance (0–8% NaCl) and were induced to secrete more EPS under salt stress. Plate experiments demonstrated that volatile organic compounds (VOCs) from the nine strains significantly promoted the root development of Arabidopsis thaliana and optimized its root architecture. Pot experiments revealed that inoculation with single strains influenced the growth of alfalfa to varying degrees; among them, strain TP14 showed the best performance, increasing plant height and shoot dry weight by 44.7% and 51.2%, respectively. Regarding microbial consortia, the combinations BD (PAP4 + TP14), ABC (PA35 + PAP4 + AC25), and ABCD (PA35 + PAP4 + AC25 + TP14) significantly improved the biomass, plant height, and stem diameter of alfalfa. The superior strains and their combinations identified in this study effectively promote plant growth. These high-performing PGPR strains provide valuable microbial resources for the development of bio-fertilizers tailored for saline–alkali and barren regions in Western China. Full article

Plant aging and senescence are key determinants of lifespan, yet the coordinated changes in endogenous polyamines and hormones during long-lived tree aging remain largely unclear. Cinnamomum camphora exhibits sequential senescence from leaves to trunk, with leaf physiology shifting toward senescence around 450 years. This study aimed to clarify the patterns of polyamines and hormones across a wide age gradient (10–810 years) and their associations with aging in ancient C. camphora. Newly expanded leaves were analyzed using curve fitting, correlation, regression, and path analysis. Tree age significantly influenced most polyamine and hormone indices, except for indole-3-acetic acid (IAA), abscisic acid (ABA), and salicylate glucoside (SAG). Spermidine (Spd) and gibberellic acid (GA) were negatively correlated with aging, and cytokinin (CK) and cadaverine (Cad) were positively correlated with aging. Free salicylic acid (SAF) was closely related to the senescence transition point. Polyamines and hormones interacted strongly. Cad was positively correlated with CK, and Spd was positively correlated with GA. A model combining Spd, GA/ABA, and CK/GA reliably predicted ancient tree age. Overall, Spd and CK exhibited the strongest negative and positive correlations with aging, respectively, providing insights into the physiological regulation of longevity in ancient trees. Full article

Both the gut and the lungs possess a microbiome, a community of commensal bacteria, archaea, fungi, and viruses that perform important housekeeping functions in those organs. The colonic microbiome primarily ferments indigestible dietary fibers into essential short-chain fatty acids, synthesizes essential vitamins, regulates the mucosal immune system, and forms a protective barrier against pathogenic colonization. The lung microbiome maintains respiratory health primarily by regulating mucosal immunity, providing a physical barrier against invading pathogens, and producing beneficial metabolites. Several colonic microbiota metabolites, including the short-chain fatty acids acetate, propionate, and butyrate, together with the tryptophan metabolites indole-3-acetate and indole-3-propionate, secondary bile acids, and the polyamines spermidine and putrescine, are transported to the lungs via the gut–lung axis. These colonic microbiota biomolecules suppress lung inflammation, strengthen immune homeostasis, and reduce the severity of respiratory diseases. In contrast, lung microorganisms and their metabolites can travel to the gut via the gut–lung axis, influencing intestinal immune responses and potentially leading to an imbalance of gut microorganisms or dysbiosis. This means that respiratory diseases may lead to digestive issues, intestinal inflammation and chronic diseases. Here, we have reviewed this crosstalk and its impact on the principal pulmonary diseases: asthma, chronic obstructive pulmonary disease, cystic fibrosis, bronchogenic carcinoma, COVID-19, interstitial lung diseases, pneumonia, and tuberculosis. It is concluded that the gut microbiome plays a significant part in lung health and disease. Diet, tobacco smoking and electronic cigarette vaping all impact both the gut and lung microbiomes. Full article

Salinization of agricultural soils is a global problem causing crop yield declines. This impact is caused by osmotic and oxidative stress, which plants often rely on endophytic bacteria to overcome. A bacterial isolate from the roots of the halophyte Plantago salsa was studied between 2024 and 2026, and its ability to increase barley tolerance to moderate salt stress was determined. Based on 16S rRNA gene sequencing (1410 bp), the isolate PS-50.1 was identified as Providencia sp. It demonstrated key plant growth-promoting properties, including indole-3-acetic acid production (21.4 mg L⁻¹) and phosphate solubilization (69.0 mg L⁻¹). The strain supported barley growth at 7% NaCl. Inoculation of barley seeds with this strain (10⁸ CFU L⁻¹) significantly reduced moderate salt stress in plants both in vitro and in a pot experiment. Inoculated plants under salinity conditions had greater shoot length (+11.6%) compared to non-inoculated; higher pre-flag leaf fresh weight; demonstrated decreased levels of prooxidants (H₂O₂ by 44.8% and malondialdehyde by 31.8%), higher proline accumulation (up to 2.0-fold), and increased antioxidant enzyme activity (catalase by 26.6% and ascorbate peroxidase by 191%). Furthermore, inoculated plants showed 9.4% higher water use efficiency and photosynthetic rate (+5.5%) under salt stress compared to uninoculated plants. These results indicate that the halophytic strain Providencia sp. PS-50.1 is a promising candidate for the development of microbial preparations aimed at increasing crop productivity under saline conditions. Full article