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Antifungal activity and mechanistic insights of total alkaloids from Sophora flavescens against Candida albicans.

Candida albicans is a major opportunistic fungal pathogen that causes a wide spectrum of infections, adversely affecting both physical and mental health. The rising incidence of antifungal resistance underscores the urgent need for novel therapeutic agents. Sophora flavescens, a traditional Chinese medicinal herb known for its antimicrobial and anti-inflammatory properties, has shown potential as an antifungal agent. This study evaluated the antifungal activity of total alkaloids from S. flavescens (TASF) against C. albicans. TASF demonstrated potent antifungal effects with an MIC of 40 mg/mL …

Computational investigation of minor alkaloids of Mitragyna speciosa Korth leaves as natural opioid analgesics.

Mitragynine is the most abundant compound in kratom (Mitragyna speciosa Korth). Furthermore, it is not explicitly mentioned which compound(s) essentially contribute to the opioid activity of this plant. In this work, we identify the compounds that are most responsible for the opioid activity. This study was completed with a comprehensive computational framework consisting of virtual screening, frontier molecular orbital profiling, prediction of ADMET properties, and validated using molecular dynamics simulations for 100 ns. The results showed that the most contributing compounds interacting wi

Four new piperidine amide alkaloids from Piper longum fruits and their anti-inflammatory activities.

Piper longum L., a widely recognized Chinese traditional spice, is extensively used as dietary flavoring agent in Southeast Asia due to its unique taste. As a dual-purpose resource for both food and medicine, the fruits of P. longum have garnered significant attention for their diverse chemical constituents and notable physiological activities. In this study, the phytochemical investigation of the fruits of P. longum resulted in the isolation and identification of 20 structurally diverse piperidine amide alkaloids, including 4 new (1a/1b-4a/b) and 16 known analogues (5-20). The enantiomeric mi…

Neuroprotective Effect of Natural Indole and β-carboline Alkaloids against Parkinson's Disease: An Overview.

Parkinson's disease (PD) is a devastating neurodegenerative condition that mostly damages dopaminergic neurons in the substantia nigra and i … g treatment for PD has been discovered using betacarboline (also known as "β-carboline") and indole alkaloids. However, there are not many studies done on this particular topic. In the herbs containing β-carbolines and indoles, the secondary metabolites and alkaloids, β-carbolines and indoles, have shown neuroprotective and cognitive-enhancing properties. I …

Exploring the anti-gout potential of sunflower receptacles alkaloids: A computational and pharmacological analysis.

Gout, a painful condition marked by elevated uric acid levels often linked to the diet's high purine and alcohol content, finds a potential treatment target in xanthine oxidase (XO), a crucial enzyme for uric acid production. This study explores the therapeutic properties of alkaloids extracted from sunflower (Helianthus annuus L.) receptacles against gout. By leveraging computational chemistry and introducing a novel R-based clustering algorithm, "TriDimensional Hierarchical Fingerprint Clustering with Tanimoto Representative Selection (3DHFC-TRS)," we assessed 231 alkaloid molecules from sun…

Bis-benzylisoquinoline alkaloids inhibit flavivirus entry and replication by compromising endolysosomal trafficking and autophagy.

Flaviviruses, such as dengue virus (DENV), Zika virus (ZIKV), and Japanese encephalitis virus (JEV), represent a substantial public health challenge as there are currently no approved treatments available. Here, we investigated the antiviral effects of bis-benzylisoquinoline alkaloids (BBAs) on flavivirus infections. We evaluated five specific BBAs-berbamine, tetrandrine, iso-tetrandrine, fangchinoline, and cepharanthine-and found that they effectively inhibited infections by ZIKV, DENV, or JEV by blocking virus entry and genome replication stages in the flavivirus life cycle. Furthermore, we …

New Imidazolium Alkaloids with Broad Spectrum of Action from the Marine Bacterium Shewanella aquimarina.

The continuous outbreak of drug-resistant bacterial and viral infections imposes the need to search for new drug candidates. Natural products from marine bacteria still inspire the design of pharmaceuticals. Indeed, marine bacteria have unique metabolic flexibility to inhabit each ecological niche, thus expanding their biosynthetic ability to assemble unprecedented molecules. The One-Strain-Many-Compounds approach and tandem mass spectrometry allowed the discovery of a Shewanella aquimarina strain as a source of novel imidazolium alkaloids via molecular networking. The alkaloid mixture was sho…

The Evolutionary Pattern of Cocaine and Hyoscyamine Biosynthesis Provides Strategies To Produce Tropane Alkaloids.

Cocaine and hyoscyamine are two tropane alkaloids (TA) from Erythroxylaceae and Solanaceae, respectively. These famous compounds possess anticholinergic properties that can be used to treat neuromuscular disorders. While the hyoscyamine biosynthetic pathway has been fully elucidated allowing its de novo synthesis in yeast, the cocaine pathway remained only partially elucidated. Recently, the Huang research group has completed the cocaine biosynthetic route by characterizing its two missing enzymes. This allowed the whole pathway to be transferring into Nicotiana benthamiana to achieve cocaine …

Prognostic risk factors for patients with hepatic sinusoidal obstruction syndrome caused by pyrrolizidine alkaloids.

Pyrrolizidine alkaloids induced hepatic sinusoidal obstruction syndrome (PA-HSOS) often occurs after consuming herbs or a dietary supplement containing the plant Tu-San-Qi. Limited data exists to identify patients with fatal outcomes for early interventions. We aimed to analyze the predictors for 3-month survival. We retrospectively enrolled PA-HSOS patients in 5 hospitals and extracted data from the onset of PA-HSOS to 36 months. Outcome measurements were 3-month and 36-month survival rates, baseline prognostic predictors for survival, and the effects of anticoagulant therapy. Among 49 enroll…

Discovery and Biosynthesis of Antimicrobial Phenethylamine Alkaloids from the Marine Flavobacterium Tenacibaculum discolor sv11.

The bacterial genus Tenacibaculum has been associated with various ecological roles in marine environments. Members of this genus can act, for example, as pathogens, predators, or episymbionts. However, natural products produced by these bacteria are still unknown. In the present work, we investigated a Tenacibaculum strain for the production of antimicrobial metabolites. Six new phenethylamine (PEA)-containing alkaloids, discolins A and B (1 and 2), dispyridine (3), dispyrrolopyridine A and B (4 and 5), and dispyrrole (6), were isolated from media produced by the predatory bacterium Tenacibac…

Total Synthesis of Spiro[cyclohexane-2-indoline] Alkaloids: A Regio- and Diastereoselective Spirocyclization Approach.

A direct spirocyclization approach for the chemical synthesis of spiro[cyclohexane-2-indoline] alkaloids is reported. The absolute stereochemistry was introduced by a desymmetrizing Dieckmann condensation, and the relative stereochemistry was controlled by the manipulation of the kinetic and thermodynamic pathways of the spirocyclization. By contrast to the biogenetic proposal involving the diester-type alkaloid as the precursor, we demonstrate that chemically a common lactone-type intermediate could bridge the chemical synthesis of this class of natural products.

New phenylpropanoids and monoterpene alkaloids with vasorelaxant activities from the branches of Alstonia scholaris.

Two new phenylpropanoids (1-2), one new nor-monoterpenoid alkaloid (3), one new monoterpene alkaloid (4), together with nine known compounds (5-13) were obtained from the branches of Alstonia scholaris. The structures of the undescribed compounds were determined by extensive spectroscopic analysis. Alkaloid 3 represented the first example of C-4 methylated nor-monoterpenoid alkaloids. A possible biosynthetic pathway for this new type of monoterpene alkaloids was proposed. All the isolates were evaluated for vasorelaxant activity against phenylephrine-induced contraction of rat mesenteric arter…

1,2-Dehydropyrrolizidine Alkaloids: Their Potential as a Dietary Cause of Sporadic Motor Neuron Diseases.

Sporadic motor neuron diseases (MNDs), such as amyotrophic lateral sclerosis (ALS), can be caused by spontaneous genetic mutations. However, … y that MNDs could be caused by intermittent, low-level dietary exposure to 1,2-dehydropyrrolizidine alkaloids (1,2-dehydroPAs) that are increasingly recognized as contaminants of many foods consumed throughout the world. Nontoxic, per se, 1,2-dehydroPAs are metabolized, by particular cytochrome P450 (CYP450) isoforms, to 6,7-dihydropyrrolizines that react w …

Monoterpene Indole Alkaloids with Cav3.1 T-Type Calcium Channel Inhibitory Activity from Catharanthus roseus.

Catharanthus roseus is a well-known traditional herbal medicine for the treatment of cancer, hypertension, scald, and sore in China. Phytochemical investigation on the twigs and leaves of this species led to the isolation of two new monoterpene indole alkaloids, catharanosines A (1) and B (2), and six known analogues (3-8). Structures of 1 and 2 were established by 1H-, 13C- and 2D-NMR, and HREIMS data. The absolute configuration of 1 was confirmed by single-crystal X-ray diffraction analysis. Compound 2 represented an unprecedented aspidosperma-type alkaloid with a 2-piperidinyl moiety at C-1…

Validation of the Nanjing Criteria for Diagnosing Pyrrolizidine Alkaloids-induced Hepatic Sinusoidal Obstruction Syndrome.

BACKGROUND AND AIMS: Hepatic sinusoidal obstruction syndrome (HSOS) is caused by toxic injury to sinusoidal endothelial cells in the liver. The intake of pyrrolizidine alkaloids (PAs) in some Chinese herbal remedies/plants remains the major etiology for HSOS in China. Recently, new diagnostic criteria for PA-induced HSOS (i.e. PA-HSOS) have been developed; however, the efficacy has not been clinically validated. This study aimed to assess the performance of the Nanjing criteria for PA-HSOS. METHODS: Data obtained from consecutive patients in multiple hospitals, which included 86 PA-HSOS patie…

Antibacterial and COX-2 Inhibitory Tetrahydrobisbenzylisoquinoline Alkaloids from the Philippine Medicinal Plant Phaeanthus ophthalmicus.

Phaeanthus ophthalmicus (Roxb. ex G.Don) J.Sinclair (previously known as P. ebracteolatus (Presl) Merr) is a Philippine medicinal plant occu … the antimicrobial and COX inhibitory activities of the extracts and tetrahydrobisbenzylisoquinoline alkaloids of P. ophthalmicus in vitro and in silico to validate its ethnomedicinal uses. Thus, the dichloromethane-methanol (DCM-MeOH) crude extract and alkaloid extracts exhibiting antibacterial activities against drug-resistant bacterial strains such as met …

Произведенные растениями алкалоиды действуют на вирусе денге и их векторах: от химии до фармакологии.

Dengue — вирусная инфекция, переносимая комарами, и ее профилактика и борьба с ней зависят от эффективных мер по борьбе с переносчиками инфекции. В настоящее время вирус денге (ДЕНВ) является эпидемией более чем в 100 странах Юго-Восточной Азии, Африки, Восточного Средиземноморья, Северной и Южной Америки и западной части Тихого океана. Несколько алкалоидов, изолированных от естественных трав, могут служить в качестве резервуара для разработки антидемонстрационных препаратов. Традиционно экстракты растений, богатые алкалоидами, используются для лечения лихорадки, а также выявляют антимикробную

Совпадение в аннотации оригинала
Dengue is a mosquito-borne viral infection, with its prevention and control depending on effective vector control measures. At present, dengue virus (DENV) is an epidemic in more than 100 countries of Southeast Asia, Africa, Eastern Mediterranean, the Americas and the Western Pacific. Several alkaloids isolated from natural herbs can serve as a reservoir for…

Alkaloids from Tabernaemontana divaricata combined with fluconazole to overcome fluconazole resistance in Candida albicans.

Nineteen indole alkaloids including eleven new ones, taberdines A-K (1-11), were isolated from Tabernaemontana divaricata. Their structures were assigned by MS, NMR, single crystal X-ray diffractions, and ECD analyses. Alkaloid 1 is an aspidosperma-type monoterpenoid indole alkaloid and possesses a rearranged pyrrolidine moiety due to C-3 degradation, and 4 has a rare 1,3-oxazolidine moiety within iboga-type alkaloids. Alkaloids 2, 4, 6, and 11-19 combined with 5 μg/mL fluconazole exhibited significant activity to reverse fluconazole resistance in Candida albicans strains while no one used alo…

Alkaloids with Anti-Onchocercal Activity from Voacanga africana Stapf (Apocynaceae): Identification and Molecular Modeling.

A new iboga-vobasine-type isomeric bisindole alkaloid named voacamine A (1), along with eight known compounds-voacangine (2), voacristine (3 … tion of the anti-onchocercal structure-activity relationship (SAR) of the isolated compounds. These alkaloids are new potential leads for the development of antifilarial drugs. The results of this study validate the traditional use of V. africana in the treatment of human onchocerciasis.

Research Progress on Anti-Inflammatory Effects and Mechanisms of Alkaloids from Chinese Medical Herbs.

As the spectrum of diseases keeps changing and life pace keeps going faster, the probability and frequency of diseases caused by human inflammatory reactions also keep increasing. How to develop effective anti-inflammatory drugs has become the hotspot of researches. It has been found that alkaloids from Chinese medical herbs have anti-inflammatory, analgesic, antitumor, anticonvulsant, diuretic, and antiarrhythmic effects, among which the anti-inflammatory effect is very prominent and commonly used in the treatment of rheumatoid arthritis, ankylosing spondylitis, and other rheumatic immune dis…