Safe Agent Research Articles

Seedless black Vitis vinifera polyphenols suppress hepatocellular carcinoma in vitro and in vivo by targeting apoptosis, cancer stem cells, and proliferation

Hepatocellular carcinoma (HCC) is an aggressive tumor and one of the most challenging cancers to treat. Here, we evaluated the in vitro and in vivo ameliorating impacts of seedless black Vitis vinifera (VV) polyphenols on HCC. Following the preparation of the VV crude extract (VVCE) from seedless VV (pulp and skin), three fractions (VVF1, VVF2, and VVF3) were prepared. The anticancer potencies of the prepared fractions, compared to 5-FU, were assessed against HepG2 and Huh7 cells. In addition, the effects of these fractions on p-dimethylaminoazobenzene-induced HCC in mice were evaluated. The predicted impacts of selected phenolic constituents of VV fractions on the activity of essential HCC-associated enzymes (NADPH oxidase “NADPH-NOX2”, histone deacetylase 1 “HDAC1”, and sepiapterin reductase “SepR”) were analyzed using molecular docking. The results showed that VVCE and its fractions induced apoptosis and collapsed CD133+ stem cells in the studied cancer cell lines with an efficiency greater than 5-FU. VVF1 and VVF2 exhibited the most effective anticancer fractions in vitro; therefore, we evaluated their influences in mice. VVF1 and VVF2 improved liver morphology and function, induced apoptosis, and lowered the fold expression of various crucial genes that regulate cancer stem cells and other vital pathways for HCC progression. For most of the examined parameters, VVF1 and VVF2 had higher potency than 5-FU, and VVF1 showed more efficiency than VVF2. The selected phenolic compounds displayed competitive inhibitory action on NADPH-NOX2, HDAC1, and SepR. In conclusion, these findings declare that VV polyphenolic fractions, particularly VVF1, could be promising safe anti-HCC agents.

Microbial- and Plant-Derived Bioactive Peptides and Their Applications against Foodborne Pathogens: Current Status and Future Prospects.

Bioactive peptides (BAPs) obtained from plants and microbes have been thoroughly explored and studied due to their prophylactic properties. The use of BAPs seems to be a promising substitute for several currently available antibiotics because of their antimicrobial properties against foodborne pathogens. BAPs have several other useful properties including antitumor, antihypertensive, antioxidant, antiobesity, and antidiabetic activities. Nowadays, scientists have attempted to recombinantly synthesize bioactive peptides to study their characteristics and potential uses, since BAPs are not found in large quantities in nature. Many pathogenic microorganisms including foodborne pathogens are becoming resistant to various antibiotics. To combat these pathogens, scientists are working to find novel, innovative, and safe antimicrobial agents. Plant- and microbe-based BAPs have demonstrated noteworthy antimicrobial activity against a wide range of pathogenic microorganisms, including foodborne pathogens. BAPs can kill pathogenic microorganisms by disrupting membrane integrity, inhibiting DNA and RNA synthesis, preventing protein synthesis, blocking protein activity, or interacting with certain intracellular targets. In addition, the positive effect of BAP consumption extends to gut microbiota modulation and affects the equilibrium of reactive oxygen species in the gut. This article discusses recombinant BAPs, BAPs generated from plants and microbes, and their antimicrobial applications and modes of action for controlling foodborne pathogens.

Biodistribution and radiation dosimetry of [99mTc]Tc-N4-BTG in patients with biochemical recurrence of prostate cancer

BackgroundIn patients with prostate cancer (PCa), imaging with gastrin-releasing peptide receptor (GRPR) ligands is an alternative to PSMA-targeted tracers, particularly if PSMA expression is low or absent. [99mTc]Tc-N4-BTG is a newly developed GRPR-directed probe for conventional scintigraphy and single photon emission computed tomography (SPECT) imaging. The current study aims to investigate the safety, biodistribution and dosimetry of [99mTc]Tc-N4-BTG in patients with biochemical recurrence (BCR) of PCa.ResultsNo adverse pharmacologic effects were observed. Injection of [99mTc]Tc-N4-BTG resulted in an effective dose of 0.0027 ± 0.0002 mSv/MBq. The urinary bladder was the critical organ with the highest mean absorbed dose of 0.028 ± 0.001 mGy/MBq, followed by the pancreas with 0.0043 ± 0.0015 mGy/MBq, osteogenic cells with 0.0039 ± 0.0005 mGy/MBq, the kidneys with 0.0034 ± 0.0003 mGy/MBq, and the liver with 0.0019 ± 0.0004 mGy/MBq, respectively. No focal tracer uptake suggestive of PCa recurrence could be revealed for any of the patients.Conclusion[99mTc]Tc-N4-BTG appears to be a safe diagnostic agent. Compared to GRPR-targeted PET tracers, this 99mTc-labelled SPECT agent could contribute to a broader application and better availability of this novel approach. Further research to assess its clinical value is warranted.

Novel CCR3-targeted cyclic peptides as potential therapeutic agents for age-related macular degeneration via inhibiting angiogenesis and reducing retinal photoreceptor damage

The prolonged intravitreal administration of anti-vascular endothelial growth factor (VEGF) drugs is prone to inducing aberrant retinal vascular development and causing damage to retinal neurons. Hence, we have taken an alternative approach by designing and synthesizing a series of cyclic peptides targeting CC motif chemokine receptor 3 (CCR3). Based on the binding mode of the N-terminal region in CCR3 protein to CCL11, we used computer-aided identification of key amino acid sequence, conformational restriction through different cyclization methods, designed and synthesized a series of target cyclic peptides, and screened the preferred compound IB-2 through affinity. IB-2 exhibits excellent anti-angiogenic activity in HRECs. The apoptosis level of 661W cells demonstrated a significant decrease with the escalating concentration of IB-2. This suggests that IB-2 may have a protective effect on photoreceptor cells. In vivo experiments have shown that IB-2 significantly reduces retinal vascular leakage and choroidal neovascularization (CNV) area in a laser-induced mouse model of CNV. These findings indicate the potential of IB-2 as a safe and effective therapeutic agent for AMD, warranting further development.

Reversible Contraception in Males: An Obtainable Target?

The last few decades have brought contraception to the forefront of research, with great strides made in effectively targeting and optimizing the physiology, pharmacology, and delivery processes that prevent pregnancy. However, these advances still predominantly target female contraceptives for the prevention of contraception, whereas targeting the male sex has lagged far behind. This has led to a marked deficiency in safe and effective male contraceptive agents, resulting in a heavy dependence on female contraceptives to prevent unwanted and unplanned pregnancies. Current research in the veterinary field and in rodents highlights several promising avenues whereby novel, safe, and effective male contraceptive alternatives are being developed-with an emphasis on reduced side effects and reversibility potential. This review aims to discuss current and novel male contraceptives (both human and veterinary formulations) while highlighting their efficacy, advantages, and disadvantages.

3-O-Substituted Quercetin: an Antibiotic-Potentiating Agent against Multidrug-Resistant Gram-Negative Enterobacteriaceae through Simultaneous Inhibition of Efflux Pump and Broad-Spectrum Carbapenemases.

The discovery of safe and efficient inhibitors against efflux pumps as well as metallo-β-lactamases (MBL) is one of the main challenges in the development of multidrug-resistant (MDR) reversal agents which can be utilized in the treatment of carbapenem-resistant Gram-negative bacteria. In this study, we have identified that introduction of an ethylene-linked sterically demanding group at the 3-OH position of the previously reported MDR reversal agent di-F-Q endows the resulting compounds with hereto unknown multitarget inhibitory activity against both efflux pumps and broad-spectrum β-lactamases including difficult-to-inhibit MBLs. A molecular docking study of the multitarget inhibitors against efflux pump, as well as various classes of β-lactamases, revealed that the 3-O-alkyl substituents occupy the novel binding sites in efflux pumps as well as carbapenemases. Not surprisingly, the multitarget inhibitors rescued the antibiotic activity of a carbapenem antibiotic, meropenem (MEM), in NDM-1 (New Delhi Metallo-β-lactamase-1)-producing carbapenem-resistant Enterobacteriaceae (CRE), and they reduced MICs of MEM more than four-fold (synergistic effect) in 8-9 out of 14 clinical strains. The antibiotic-potentiating activity of the multitarget inhibitors was also demonstrated in CRE-infected mouse model. Taken together, these results suggest that combining inhibitory activity against two critical targets in MDR Gram-negative bacteria, efflux pumps, and β-lactamases, in one molecule is possible, and the multitarget inhibitors may provide new avenues for the discovery of safe and efficient MDR reversal agents.

Safety, Analgesic, and Anti-Inflammatory Effects of Aqueous and Methanolic Leaf Extracts of Hypericum revolutum subsp. keniense

In light of the enduring obstacles encountered in analgesia and anti-inflammatory therapeutics despite the strides made in contemporary medical sciences, the quest for alternative efficacious strategies is an imperative pursuit. Thus, this study investigated the safety profiles, as well as the analgesic and anti-inflammatory attributes, of aqueous and methanolic leaf extracts derived from Hypericum revolutum subsp. keniense—a botanical entity entrenched in historical ethnomedicinal practices in the Kenyan context. The assessment of acute oral toxicity of these extracts was conducted in accordance with the Up- and-Down method advocated by the Organisation for Economic Cooperation and Development (OECD), utilizing Swiss albino mice as the experimental subjects. Subsequent investigation entailed the evaluation of antinociceptive and anti-inflammatory properties employing the acetic acid-induced writhing and carrageenan-induced paw oedema methodologies, respectively, in the same murine model. The findings of this study evince the safety of both aqueous and methanolic extracts, with LD50 values surpassing 2000 mg/kg body weight and the absence of discernible signs of toxicity. Furthermore, a notable dose-dependent (P<0.05) manifestation of analgesic effects was observed for both extracts, with the aqueous variant demonstrating heightened potency compared to its methanolic counterpart (P<0.05). Moreover, the anti-inflammatory efficacy escalated significantly with escalating extract doses and prolonged treatment duration (P<0.05), wherein the aqueous extract showcased superior effectiveness vis- à-vis the methanolic extract across all dosage regimens and temporal checkpoints (P<0.05). Therefore, this investigation underscores the latent promise of the examined extracts as reservoirs of safe and efficacious analgesic and anti-inflammatory agents, thereby meriting further meticulous exploration. Subsequent research endeavours ought to pivot towards elucidating the phytochemical constituents underpinning the observed effects, alongside unravelling their mechanistic underpinnings across a spectrum of animal models and clinical milieus.

Drosophila melanogaster as a model organism for diabetes II treatment by the ethyl acetate fraction of Atriplex halimus L.

Type 2 diabetes (T2D) is the most common metabolic disorder. The undesirable effects of synthetic drugs demand a search for safe antidiabetic agents. This study aimed to assess the antidiabetic activity of different fractions of Atriplex halimus (petroleum ether 60-80, methylene chloride, ethyl acetate, and n-butanol) using Drosophila melanogaster larvae. Titers of total glucose and trehalose, as well as larval weight, were measured and compared with those of control and diabetic larvae. The expression of Drosophila insulin-like peptides (DILP2 and DILP3) and adipokinetic hormone (AKH) was evaluated. The results revealed a significant increase in total glucose, trehalose, and a decrease in body weight in the larvae fed a high-sugar diet compared with those in the control. When larvae fed diets containing the tested fractions, the total glucose and trehalose decreased to the control level, and the body weight increased. DILP2, DILP3, and AKH exhibited significant decreases upon treatment with A. halimus ethyl acetate. Metabolomic profiling of the ethyl acetate fraction of A. halimus revealed the presence of flavonoids and flavonoid glycosides. After docking screening to predict the most powerful moiety, we discovered that flavonoid glycosides (especially eriodictyol-7-O-neohesperidoside) have a greater affinity for the pocket than the other moieties. The results indicated the therapeutic activity of the A. halimus ethyl acetate fraction against induced T2D in Drosophila larvae. The antidiabetic activity may be attributed to flavonoids, which are the main components of the A. halimus ethyl acetate fraction.

Carbon Nanodisks Decorated with Guanidinylated Hyperbranched Polyethyleneimine Derivatives as Efficient Antibacterial Agents.

Non-toxic carbon-based hybrid nanomaterials based on carbon nanodisks were synthesized and assessed as novel antibacterial agents. Specifically, acid-treated carbon nanodisks (oxCNDs), as a safe alternative material to graphene oxide, interacted through covalent and non-covalent bonding with guanidinylated hyperbranched polyethyleneimine derivatives (GPEI5K and GPEI25K), affording the oxCNDs@GPEI5K and oxCNDs@GPEI25K hybrids. Their physico-chemical characterization confirmed the successful and homogenous attachment of GPEIs on the surface of oxCNDs, which, due to the presence of guanidinium groups, offered them improved aqueous stability. Moreover, the antibacterial activity of oxCNDs@GPEIs was evaluated against Gram-negative E. coli and Gram-positive S. aureus bacteria. It was found that both hybrids exhibited enhanced antibacterial activity, with oxCNDs@GPEI5K being more active than oxCNDs@GPEI25K. Their MIC and MBC values were found to be much lower than those of oxCNDs, revealing that the GPEI attachment endowed the hybrids with enhanced antibacterial properties. These improved properties were attributed to the polycationic character of the oxCNDs@GPEIs, which enables effective interaction with the bacterial cytoplasmic membrane and cell walls, leading to cell envelope damage, and eventually cell lysis. Finally, oxCNDs@GPEIs showed minimal cytotoxicity on mammalian cells, indicating that these hybrid nanomaterials have great potential to be used as safe and efficient antibacterial agents.

Pesticidal activity of extra cellular metabolites extracted from the green muscardian fungi Metarhizium anisopliae

AbstractThe present study was undertaken to screen the pesticidal activity of extra cellular metabolites derived from entomopathogenic fungus Metarhizium anisopliae against Spodoptera litura and Aphis crassivora an important aphid pest under laboratory and pot culture condition. Fungal strain used in the study was isolated from the soil by serial dilution technique. Isolated fungal strain was mass multiplied in a liquid medium sabouraud maltose yeast extract broth under optimum condition (28°C). Culture filtrate and the collected culture derived from the medium was used for the source of metabolites. The culture filtrate was extracted with ethyl acetate, acetone and the concentrated extract was screened for pesticidal activity against Spodoptera litura and Aphis crassivora adopting leaf disc and pot culture assay respectively. Extracted metabolites showed pesticidal activity against both insect pests. However, notable effect was recorded in ethyl acetate derived metabolites. The ethyl acetate extract treatment recorded 91.2% mortality at a concentration of 100 μg against Spodoptera litura and 100% mortality at a concentration of 100 μg against Aphis crassivora. Phytotoxicity was determined by measuring the germination index (GI) of groundnut seeds by exposing it to the crude metabolites extracted in ethyl acetate and acetone. The results showed that the germination index was high on ethyl acetate extract which was recorded to be 98.0% and germination index of acetone extract was found to be 90.0%. Production of insecticidal metabolites from M. anisopliae under laboratory condition proposed the possible utilization of metabolites as an effective, safe pesticidal agent against economic important insect pests. No impact on the seedling emergence revealed non phytotoxic effect of the metabolites.

Terminalia bellirica Extract Suppresses SARS-Cov-2 Nucleocapsid-Induced Inflammation in A549 Cells

SARS-CoV-2 infection triggers a host-immune response via cytokine release that, when excessive, leads to severe inflammation and life-threatening complications. To reduce the risks associated with cytokine storms, alternative approaches are needed. Traditional Thai herbal extracts are recognized for their potential as safe and effective anti-inflammatory agents against various diseases. Hence, this study aims to examine the anti-inflammatory effects of ethanolic extracts from Terminalia chebula, Terminalia bellirica, Phyllanthus emblica, and Andrographis paniculata in reducing inflammation in the A549 alveolar basal epithelial cell lines. We conducted a comparative analysis of the anti-inflammation efficacy of four extracts in reducing the COX-2 upregulation induced by TNF-α stimulation in A549 cells. Among them, T. bellirica exhibited the highest effectiveness in reducing COX-2 levels to 0.38-fold. Furthermore, we validated the anti-inflammation properties of T. bellirica in diminishing inflammation-induced SARS-CoV-2 nucleocapsid. Lentivirus transduction expressing SARS-CoV-2 nucleocapsid demonstrated a dose-dependent increase in the expression of pro-inflammatory cytokines and mediators including TNF-α, IL-8, CXCL-10, and COX-2. Interestingly, treatment with sublethal doses of T. bellirica (30 and 60 μg/mL) led to a significant reduction in COX-2 expression by 30% and 70%, TNF-α by 46% and 75%, IL-8 by 39% and 48%, and CXCL-10 by 46% and 80%, respectively. These findings confirm the potent anti-inflammatory effects of T. bellirica, highlighting its potential as a novel treatment for alleviating the severity of cytokine storms in SARS-CoV-2 and related diseases.

Efficacy and Safety of PEGylated Interferons for Relapsing-Remitting Multiple Sclerosis in Adult Patients: Results of Matching-Adjusted Indirect Comparison

Introduction. Beta interferons are effective and safe agents for the treatment of relapsing-remitting multiple sclerosis (RRMS). PEGylated interferons have been developed in order to increase patient adherence. Direct comparisons of the efficacy and safety of PEGylated interferons have not yet been conducted. Our objective was to evaluate the efficacy and safety of SamPEG-IFN-β1a versus PEG-IFN-β1a in adult patients with RRMS. Materials and methods. We conducted a systematic search of randomized clinical trials (RCTs) using the PubMed, Embase and eLIBRARY.RU databases. Efficacy was assessed based on the proportion of patients with disease relapses and the annualized relapse rate (ARR) during the 1st and the 2nd years of treatment. Safety was assessed by the number of patients with adverse events (AEs), serious AEs (SAEs), and any AEs that led to the treatment discontinuation. We conducted pairwise matching-adjusted indirect comparison (MAIC) to assess comparative efficacy of PEGylated IFNs. To evaluate the efficacy, hypotheses of non-inferiority of SamPEG-IFN-β1a to PEG-IFN-β1a and superiority of SamPEG-IFN-β1a over PEG-IFN-β1a were tested. Results. Based on results of the systematic review, four articles were selected wherein the results of phase 3 clinical trial of PEG-IFN-β1a and phase 2–3 clinical trial of SamPEG-IFN-β1a were described. In PEG-IFN-β1a group (n = 512) the agent was administered once every 2 weeks, in SamPEGIFN-β1a group (n = 114) the agent was administered at a dose of 240 μg. The analysis results confirmed the hypothesis of SamPEG-IFN-β1a non-inferiority to PEG-IFN-β1a in efficacy, while SamPEG-IFN-β1a superiority over PEG-IFN-β1a in efficacy was not confirmed. The hypothesis of SamPEG-IFN-β1a superiority over PEG-IFN-β1a in safety was also confirmed based on a significantly lower incidence of SAEs and any AEs that led to treatment discontinuation. Conclusions. The proportion of patients with relapses and the ARR in 1 year and in 2 years of therapy indicates that SamPEG-IFN-β1a is non-inferior to PEG-IFN-β1a in efficacy. SamPEG-IFN-B1a demonstrated a more favourable safety profile than PEG-IFN-B1a as showing less odds of SAEs and AEs leading to treatment discontinuation.

Using a Drug Repurposing Strategy to Virtually Screen Potential HIV-1 Entry Inhibitors That Block the NHR Domain of the Viral Envelope Protein gp41

Using a drug repurposing strategy, virtual screening of potential inhibitors of the NHR domain of the HIV-1 gp41 protein, a conserved region critical for the virus-cell membrane fusion and viral infectivity, was carried out. The used computational approach included: (1) molecular docking of this functionally significant region of the HIV-1 envelope with compounds from a library of bioactive molecules containing clinically approved drugs, experimental drugs, and investigational drug candidates; (2) assessing the binding affinity of these compounds to the therapeutic target; (3) molecular dynamics simulations of ligand/NHR-gp41 complexes; (4) calculations of the binding free energy followed by the analysis of molecular dynamics trajectories and selection of compounds promising to test for anti-HIV-1 activity. As a result, six compounds that exhibited the high binding affinity to the NHR domain of the HIV-1 gp41 protein and showed acceptable pharmacological properties were identified. The predicted compounds are assumed to form a promising basis for the development of new, effective and safe broad-spectrum antiviral agents able to inhibit the HIV-1 entry into the host cell.

Antiplasmodial Activity and Phytochemical Evaluation of the Stems of Albizia coriaria and Ficus sur

Background: Malaria continues to cause havoc on various populations because of the high mortality and economic burden associated with the disease. Progress made in the therapeutics of the disease is threatened by the emerging parasite resistance to currently used first line treatment drugs. This has prompted the search for new, effective, and safe antimalarial agents. The use of traditional medicine in the treatment of various types of diseases including malaria is a regular practice seen with many cultures in Ghana. The stems of Albizia coriaria Welw ex. Oliver and Ficus sur Forssk are such plants used with little evidence about their in vivo efficacy. Aim: This study therefore aimed to assess the in vivo antiplasmodial potential, and the acute toxicity of the hydroethanolic stem extract of Albizia coriaria and Ficus sur. Method: Qualitative phytochemical screening was done on the powdered plant material using standard methods. Acute toxicity was carried out according to OECD guidelines using the Limit test. In vivo antiplasmodial activity of the hydroethanolic extract was assessed using the Peter’s 4-day suppressive and Rane’s curative test. Results: The 70% ethanol extract was safe with the lethal dose above 3000 mg/kg. All the extracts significantly (P < 0.05) suppressed parasitaemia in the Peter’s suppressive and Rane’s curative test with Albizia coriaria producing the highest chemotherapeutic activity of 68.89 and 61.46% in the suppressive and curative test respectively. That of F. sur was less than 50% in both assays. Artesunate reference drug recorded over 80% suppression in the curative test but lesser activity in the suppression assay compared to A. coriaria. Several plant metabolites including terpenoids, flavonoids and coumarins were found in both plant samples. Conclusion: Albizia coriaria and Ficus sur 70% ethanol extract showed considerable antiplasmoidal activity and were found to be non-toxic in acute toxicity study, thus justifying their safe use in the treatment of malaria as suggested by folklore medicine.

Repurposing mebendazole against triple-negative breast cancer CNS metastasis.

Triple-negative breast cancer (TNBC) often metastasizes to the central nervous system (CNS) and has the highest propensity among breast cancer subtypes to develop leptomeningeal disease (LMD). LMD is a spread of cancer into leptomeningeal space that speeds up the disease progression and severely aggravates the prognosis. LMD has limited treatment options. We sought to test whether the common anti-helminthic drug mebendazole (MBZ) may be effective against murine TNBC LMD. A small-molecule screen involving TNBC cell lines identified benzimidazoles as potential therapeutic agents for further study. In vitro migration assays were used to evaluate cell migration capacity and the effect of MBZ. For in vivo testing, CNS metastasis was introduced into BALB/c athymic nude mice through internal carotid artery injections of brain-tropic MDA-MB-231-BR or MCF7-BR cells. Tumor growth and spread was monitored by bioluminescence imaging and immunohistochemistry. MBZ was given orally at 50 and 100mg/kg doses. MBZ bioavailability was assayed by mass spectrometry. Bioinformatic analysis and migration assays revealed higher migratory capacity of TNBC compared to other breast cancer subtypes. MBZ effectively slowed down migration of TNBC cell line MDA-MB-231 and its brain tropic derivative MDA-MB-231-BR. In animal studies, MBZ reduced leptomeningeal spread, and extended survival in brain metastasis model produced by MDA-MB-231-BR cells. MBZ did not have an effect in the non-migratory MCF7-BR model. We demonstrated that MBZ is a safe and effective oral agent in an animal model of TNBC CNS metastasis. Our findings are concordant with previous efforts involving MBZ and CNS pathology and support the drug's potential utility to slow down leptomeningeal spread.

An Approach for Engineering Peptides for Competitive Inhibition of the SARS-COV-2 Spike Protein.

SARS-CoV-2 is the virus responsible for a respiratory disease called COVID-19 that devastated global public health. Since 2020, there has been an intense effort by the scientific community to develop safe and effective prophylactic and therapeutic agents against this disease. In this context, peptides have emerged as an alternative for inhibiting the causative agent. However, designing peptides that bind efficiently is still an open challenge. Here, we show an algorithm for peptide engineering. Our strategy consists of starting with a peptide whose structure is similar to the interaction region of the human ACE2 protein with the SPIKE protein, which is important for SARS-COV-2 infection. Our methodology is based on a genetic algorithm performing systematic steps of random mutation, protein-peptide docking (using the PyRosetta library) and selecting the best-optimized peptides based on the contacts made at the peptide-protein interface. We performed three case studies to evaluate the tool parameters and compared our results with proposals presented in the literature. Additionally, we performed molecular dynamics (MD) simulations (three systems, 200 ns each) to probe whether our suggested peptides could interact with the spike protein. Our results suggest that our methodology could be a good strategy for designing peptides.

Transcriptomic and biochemical analyses reveal the antifungal mechanism of cell-free supernatant from Aspergillus luchuensis YZ-1 against Aspergillus flavus

Aspergillus flavus (A. flavus) and its metabolites, aflatoxins, are widespread in crops and foods, threatening public health. Using chemical fungicides to control A. flavus can pose safety hazards and cause environmental pollution. Therefore, there is an urgent need for safe and effective antifungal agents to control A. flavus. In this study, we isolated Aspergillus luchuensisYZ-1 cell-free supernatant (CFS), volatiles, and mycelial extracts to investigate their inhibitory effects on A. flavus. Results indicate that the CFS exhibited greater efficacy in impeding the growth and synthesis of aflatoxin B1 (AFB1) in A. flavus. Transcriptomic analysis revealed a significant downregulation of lipid metabolism, biosynthesis of other secondary metabolites, and glycan metabolism in A. flavus treated with CFS. Approximately 94% of the genes in the aflatoxin synthesis pathway were significantly downregulated. Furthermore, the CFS treatment significantly increased reactive oxygen species (ROS) production in A. flavus, affected its energy metabolism, and upregulated methane metabolism and the pentose phosphate pathway. We then investigated the inhibitory mechanism of YZ-1 against A. flavus by biochemical analysis. It was further confirmed that CFS had destructive effects in the cell wall and cell membrane of A. flavus, as indicated by leakage of nucleic acids, proteins, alkaline phosphatase (AKP), as well as decreased chitin and ergosterol content. In summary, this study provides novel insights into the mechanisms of CFS against A. flavus, suggesting its potential as a biocontrol agent in food and agriculture.

Antiplasmodial potential of phytochemicals from Citrus aurantifolia peels: a comprehensive in vitro and in silico study

Phytochemical investigation of Key lime (Citrus aurantifolia L., F. Rutaceae) peels afforded six metabolites, known as methyl isolimonate acetate (1), limonin (2), luteolin (3), 3ˋ-hydroxygenkwanin (4), myricetin (5), and europetin (6). The structures of the isolated compounds were assigned by 1D NMR. In the case of limonin (2), further 1- and 2D NMR experiments were done to further confirm the structure of this most active metabolite. The antiplasmodial properties of the obtained compounds against the pathogenic NF54 strain of Plasmodium falciparum were assessed in vitro. According to antiplasmodial screening, only limonin (2), luteolin (3), and myricetin (5) were effective (IC50 values of 0.2, 3.4, and 5.9 µM, respectively). We explored the antiplasmodial potential of phytochemicals from C. aurantifolia peels using a stepwise in silico-based analysis. We first identified the unique proteins of P. falciparum that have no homolog in the human proteome, and then performed inverse docking, ΔGBinding calculation, and molecular dynamics simulation to predict the binding affinity and stability of the isolated compounds with these proteins. We found that limonin (2), luteolin (3), and myricetin (5) could interact with 20S a proteasome, choline kinase, and phosphocholine cytidylyltransferase, respectively, which are important enzymes for the survival and growth of the parasite. According to our findings, phytochemicals from C. aurantifolia peels can be considered as potential leads for the development of new safe and effective antiplasmodial agents.

Inorganic and organic chemical constituents of trona, alum and palm ash: Potential alternatives to conventional antifungal drugs?

There is high demand for the development of novel, effective, clinically safe and affordable antifungal agents to manage the ever emerging and re-emerging fungal infections. Natural compounds may be a source of novel chemical structures for development of antimicrobials. The aim of this study was to determine the inorganic and organic chemical constituents of trona, alum and palm ash; as potential alternatives to conventional antifungal drugs. The fungal isolates were obtained from high vaginal swab samples of patients suffering from vulvo-vaginal candidiasis. The isolates were identified based on their macroscopic, physiological, biochemical and molecular characteristics. The minimal inhibitory concentration (MIC) and minimal fungicidal concentrations (MFC) of the test agents were determined using the broth dilution method. Gas chromatography-mass spectroscopy (GC-MS) was used to determine the organic constituents; while x-ray fluorescence spectroscopy, for inorganic constituents. The isolates include Candida albicans, C. tropicalis, C. glabrata and C. parapsilosis. The MIC and MFC of alum against the isolates ranged from 12.50 mg/ml to 50 mg/ml, trona (6.25 mg/ml to 100 mg/ml) and palm ash (100 mg/ml to 200 mg/ml). Alum comprises oxides of sulphur (44.5 %), aluminium (14.49 %) while lead, arsenic and nickel all accounted for <0.0010 %. The naturally occurring fatty acids include vaccenic acid (40.39 %), decanoic acid (13.21 %) and linoelaidic acid (9.84 %). Trona comprises of sulphur (2.14 %), chlorine (5.8 %), potassium (1.7 %), lead (0 %), arsenic and nickel (<0.003 %); while the organic constituents include linoelaidic acid (32.99 %), nonanoic acid (14.81 %) and decanoic acid (6.8 %). The inorganic components of palm ash include potassium (28.8 %), sulphur (3.4 %), calcium (2.8 %) and chlorine (15 %) while the heavy metals all accounted for <0.0007 %. The organic constituents were urea (8.65 %) and fatty acids (<6 %). The antimicrobial properties of the natural compounds were probably due to their various organic and inorganic constituents; thus, could serve as potential raw materials in antifungal drugs production.

Animal Venoms as Potential Source of Anticonvulsants.

Epilepsy affects millions of people worldwide, and there is an urgent need to develop safe and effective therapeutic agents. Animal venoms contain diverse bioactive compounds like proteins, peptides, and small molecules, which may possess medicinal properties against epilepsy. In recent years, research has shown that venoms from various organisms such as spiders, ants, bees, wasps, and conus snails have anticonvulsant and antiepileptic effects by targeting specific receptors and ion channels. This review underscores the significance of purified proteins and toxins from these sources as potential therapeutic agents for epilepsy. In conclusion, this review emphasizes the valuable role of animal venoms as a natural resource for further exploration in epilepsy treatment research.