Antimicrobial phenolic derivatives fromDendranthema zawadskii var.latilobum kitamura (Asteraceae)

Vepris amaniensis: a morphological, biochemical, and molecular investigation of a species complex

Vepris Comm. ex A. Juss. is a genus of 96 species extending from Africa to India that are distinct in their unarmed stems and their digitately (1-)3(-5) foliolate leaflets, and whose many secondary compounds earn them uses in traditional medicine. Mziray (1992) subsumed six related genera into Vepris, with Vepris amaniensis (Engl.) Mziray becoming somewhat of a dustpan for ambiguous specimens (Cheek & Luke, 2023). This study, using material from the Kew herbarium, sought to pull out novel species from those previously incorrectly filed as Vepris amaniensis, and here describes the new species Vepris usambarensis sp. nov. This species is morphologically distinct from Vepris amaniensis with its canaliculate to winged petioles, 0.5-2.3 cm long inflorescences, 1-3 foliolate leaflets, and hairs on inflorescences and stem apices. Phytochemical analysis attributed seven compounds to Vepris usambarensis: tecleanthine (1), evoxanthine (2), 6-methoxytecleanthine (3), tecleanone (4), 1-(3,4-methylenedioxyphenyl)-1,2,3-propanetriol (5), lupeol (6), and arborinine (7). This is a unique mixture of compounds for a species of Vepris, though all are known to occur in the genus, with the exception of 1-(3,4-methylenedioxyphenyl)-1,2,3-propanetriol (5) which was characterized from a species in the Asteraceae. An attempt at constructing a phylogeny for Vepris using the ITS and trnL-F regions was made, but these two regions could not be used to differentiate at species level and it is suggested that 353 sequencing is used for further research. Originally more than one new species was hypothesized to be within the study group; however, separating an additional species was unsupported by the data produced. Further phylogenetic analysis is recommended to fully elucidate species relationships and identify any cryptic species that may be present within Vepris usambarensis.

Composition of Sphagnum palustre L. extracts using different extraction methods

Sphagnum palustre L. is a Chinese herbal medicine with a long history, however, few studies have been performed on its chemical composition and active effects. In this study, we investigated the composition and antibacterial and antioxidant capacities of extracts obtained from Sphagnum palustre L. phytosomes extracted with conventional solvents (water, methanol, and ethanol) and two different hydrogen bond donors (citric acid and 1,2-propanediol) modified with choline chloride-type deep eutectic solvents (DESs). The results show that Sphagnum palustre extracts contained 253 compounds, including citric acid, ethyl maltol, and thymol. The highest total phenolic content (TPC) was obtained with a DES extraction method combining 1,2-propanediol and choline chloride (39.02 ± 7.08 mg gallic acid equivalent/g dried weight (DW). This shows the composition of Sphagnum palustre as a natural product and the application of DESs in the extraction of active ingredients, demonstrating the potential of peat moss extracts in cosmetics and health products.

Chemical constituents from the stems and leaves of Amomum villosum Lour. and their anti-inflammatory and antioxidant activities

Amomum villosum Lour. is a medicinal and edible plant, whose medicinal parts are dried and mature fruits, and its stems and leaves are always treated as waste. HPLC-MS/MS analysis showed that the chemical components contained in the stems/leaves of A. villosum and those in fruits are quite different. To discover potential active ingredients from the stems/leaves of A. villosum, phytochemical evaluation of the stems/leaves of A. villosum was conducted to isolate and identify-four undescribed compounds (1, 2a, 2b, and 3) along with 41 known ones (4a, 4b, 5a, 5b, and 6-42). All isolated compounds were assessed for their anti-inflammatory and antioxidant activities. Among them, compounds 5b, 33, 34, and 38 exhibited anti-inflammatory activity, and compounds 1, 4a, 4b, 6, 7, 15, 33, 35, 37, and 41 showed antioxidant effects. Among them, the new compound 1 showed a significant antioxidant effect via activation of NRF2/HO-1 pathways. Therefore, the leaves and stems of A. villosum may be served as a potential medicine or dietary supplement for preventing and treating diseases resulting from inflammation and oxidative stress.

Screening of secondary metabolites and antioxidant potential of endophytic fungus Penicillium citrinum and host Digitaria bicornis by spectrophotometric and electrochemical methods

Perennial grasses are hosts to an extremely diverse assemblage of endophytic fungi, but their significance is still underexplored. In the present study, an endophytic fungus was isolated from the aerial regions of Digitaria bicornis (Lam.) Roem. & Schult. and was characterized by morphological and molecular methods (ITS rDNA region), as Penicillium citrinum Thom. The crude extracts of endophytic fungus and host were recovered and evaluated for their antioxidant potential by spectrophotometric and electrochemical methods. The present study was also an attempt to compare the anti-radical power of extracts by spectrophotometric (2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), hydrogen peroxide and nitric oxide radical scavenging assay) and electrochemical (cyclic voltammetry) methods and suggested that cyclic voltammetry could be used routinely instead of assaying by more number of spectrophotometric methods. The results indicated that the ethyl acetate extract of P. citrinum and methanolic extract of D. bicornis has potential compounds with antioxidant and other pharmaceutical activities. Nine and 17 antioxidant biomolecules, respectively, in P. citrinum and D. bicornis extracts were detected by OHR-LC-MS and the presence of function group of the bioactive compounds was confirmed by FTIR spectroscopy. Finally, the study also reported that the extracts of P. citrinum and D. bicornis have several bioactive compounds with application in commercial pharmaceutical industries.

Isolation, Identification and Pharmacological Effects of Mandragora autumnalis Fruit Flavonoids Fraction

Since ancient times, Mandragora autumnalis has been used as a traditional medicinal plant for the treatment of numerous ailments. In light of this, the current study was designed to isolate and identify the chemical constituents of the flavonoids fraction from M. autumnalis ripe fruit (FFM), and evaluate its DPPH scavenging, anti-lipase, cytotoxicity, antimicrobial and antidiabetic effects. An ethyl acetate extract of M. autumnalis was subjected to a sequence of silica gel column chromatography using different eluents with various polarities. The chemical structures of the isolated compounds were identified using different spectral techniques, including ¹H NMR and ¹³C NMR. FFM's anti-diabetic activity was assessed using a glucose transporter-4 (GLUT4) translocation assay, as well as an inhibition against α-amylase and α-glucosidase using standard biochemical assays. The FFM anti-lipase effect against porcine pancreatic lipase was also evaluated. Moreover, FFM free radical scavenging activity using the DPPH test and antimicrobial properties against eight microbial strains using the micro-dilution method were also assessed. Four flavonoid aglycones were separated from FFM and their chemical structures were identified. The structures of the isolated compounds were established as kaempferol 1, luteolin 2, myricetin 3 and (+)-taxifolin 4, based on NMR spectroscopic analyses. The cytotoxicity test results showed high cell viability (at least 90%) for up to 1 mg/mL concentration of FFM, which is considered to be safe. A dose-dependent increase in GLUT4 translocation was significantly shown (p < 0.05) when the muscle cells were treated with FFM up to 0.5 mg/mL. Moreover, FFM revealed potent α-amylase, α-glucosidase, DPPH scavenging and porcine pancreatic lipase inhibitory activities compared with the positive controls, with IC₅₀ values of 72.44 ± 0.89, 39.81 ± 0.74, 5.37 ± 0.41 and 39.81 ± 1.23 µg/mL, respectively. In addition, FFM inhibited the growth of all of the tested bacterial and fungal strains and showed the greatest antibacterial activity against the K. pneumoniae strain with a MIC value of 0.135 µg/mL. The four flavonoid molecules that constitute the FFM have been shown to have medicinal promise. Further in vivo testing and formulation design are needed to corroborate these findings, which are integral to the pharmaceutical and food supplement industries.

Recent Developments in Therapeutic and Nutraceutical Applications of p-Methoxycinnamic Acid from Plant Origin

The p-methoxycinnamic acid (p-MCA) is one of the most studied phenylpropanoids with high importance not only in the wide spectrum of therapeutic activities but also its potential application for the food industry. This natural compound derived from plants exhibits a wide range of biologically useful properties; therefore, during the last two decades it has been extensively tested for therapeutic and nutraceutical applications. This article presents the natural sources of p-MCA, its metabolism, pharmacokinetic properties, and safety of its application. The possibilities of using this dietary bioactive compound as a nutraceutical agent that may be used as functional food ingredient playing a vital role in the prevention and treatment of many chronic diseases is also discussed. We present the antidiabetic, anticancer, antimicrobial, hepato-, and neuroprotective activities of p-MCA and methods of its lipophilization that have been developed so far to increase its industrial application and bioavailability in the biological systems.

Acacetin, a flavone with diverse therapeutic potential in cancer, inflammation, infections and other metabolic disorders

BACKGROUND

Acacetin is a di-hydroxy and mono-methoxy flavone present in various plants, including black locust, Damiana, Silver birch. Literature information revealed that acacetin exhibits an array of pharmacological potential including chemopreventive and cytotoxic properties in cancer cell lines, prevents ischemia/reperfusion/myocardial infarction-induced cardiac injury, lipopolysaccharide (LPS), 1-methyl-4-phenyl pyridinium ion (MPP+) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP)-induced neuroinflammation, LPS and sepsis-induced lung injury, rheumatoid and collagen-induced arthritis, inhibit the microbial growth, obesity, viral-mediated infections as well as hepatic protection.

PURPOSE

This review highlights the therapeutic potential of acacetin, with updated and comprehensive information on the biological sources, chemistry, and pharmacological properties along with the possible mechanism of action, safety aspects, and future research opportunities.

STUDY DESIGN

The information was retrieved from various search engines, including Pubmed, SciFinder, Science direct, Inxight:drugs, Google scholar, and Meta cyc.

RESULT

The first section of this review focuses on the detailed biological source of acacetin, chromatographic techniques used for isolation, chemical characteristics, the method for the synthesis of acacetin, and the available natural and synthetic derivatives. Subsequently, the pharmacological activities, including anti-cancer, anti-inflammatory, anti-viral, anti-microbial, anti-obesity, have been discussed. The pharmacokinetics data and toxicity profile of acacetin are also discussed.

CONCLUSION

Acacetin is a potent molecule reported for its strong anti-inflammatory and anti-cancer activity, however further scientific evidence is essential to validate its potency in disease models associated with inflammation and cancer. There is limited information available for toxicity profiling of acacetin; therefore, further studies would aid in establishing this natural flavone as a potent candidate for research studies at clinical setup.

Triculata A, a novel compound from Tricyrtis maculata (D. Don) J. F. Macbr. with biological properties

A novel compound, triculata A (1), and seven known compounds were obtained from the Tricyrtis maculata (D. Don) J. F. Macbr.. The structure of the new compound was determined by extensive spectroscopic methods, and its absolute configuration was assigned by single-crystal X-ray diffraction analysis. Compound 1 features a rare naphtho[b,c]pyran carbon skeleton that was found in nature for the first time. Compounds 2-4, 6 and 7 showed potential vasodilatory effects with EC₅₀ values ranging from 7.3 to 111.3 μM. Compounds 1, 3-5 and 7 possessed remarkable antioxidant capacity evaluated by DPPH and ABTS assays.

Antibacterial and Potential Antidiabetic Activities of Flavone C-glycosides Isolated from Beta vulgaris Subspecies cicla L. var. Flavescens (Amaranthaceae) Cultivated in Egypt

BACKGROUND

Diabetes mellitus is the most common disease in Egypt. In this context, Beta vulgaris subspecies cicla L. var. flavescens is an edible plant that has been used in traditional medicine as a therapy for treating some diseases.

OBJECTIVES

The current study was performed to evaluate the antibacterial and potential anti-diabetic activities of different extracts and isolated flavone C-glycoside compounds isolated from Beta vulgaris subspecies cicla L. var. flavescens leaves.

METHODS

Phytochemical investigation of n-butanol extract led to the isolation of five phytoconstituents. Their structures were determined by spectroscopic tools, including 1D-NMR (1H- & 13C-NMR) and 2D-NMR (HMQC & HMBC) besides the comparison of the data with the literature. The extracts and phytoconstituents were evaluated in vitro for their activity against some bacterial pathogens, which represent prominent human pathogens, particularly in hospital settings. The antibacterial activity was examined against three Gram-positive bacterial strains (Staphylococcus aureus, Staphylococcus epidermidis & Enterococcus faecalis) and five Gram-negative ones (Pseudomonas aeruginosa, Proteus vulgaris, Klebsiella pneumoniae, Proteus mirabilis & Salmonella typhimurium) relative to Ciprofloxacin as a reference drug. Furthermore, the in vitro antidiabetic activity (Type II) was evaluated using the alpha-glucosidase inhibitory assay.

RESULTS

Five flavone C-glycosides namely; Apigenin 8-C-β-D-glucopyranoside (vitexin) (1), 2''-Oxylopyranosylvitexin (2), acacetin 8-C-β-D-glucopyranoside (3), acacetin 8-C-α-L-rhamnoside (4), and 6,8-di-C-β-D-glucopyranosylapigenin (vecinin-II) (5) were isolated from n-butanol extract of B. vulgaris subspecies cicla L. var. flavescens. Compound 1 showed a promising antibacterial activity against most of the test bacterial strains with respect to the minimum inhibitory concentration values (MIC) ranged from 1.95 to 15.63 µg ml-1. On the other hand, compounds 1 and 3 demonstrated superior antidiabetic activities with IC50 values of 35.7 and 42.64 µg ml-1, respectively, while an inferior potential antidiabetic activity was recorded for compound 4 (IC50 = 145.5 µg ml-1) in comparison with Acarbose as a reference drug.

CONCLUSION

B. vulgaris L. is an edible plant, which could be used as a natural source of antibiotic and hypoglycemic drugs.

Isolation of Antimicrobial Compounds From Cnestis ferruginea Vahl ex. DC (Connaraceae) Leaves Through Bioassay-Guided Fractionation

Different parts of Cnestis ferruginea are used in traditional African medicine for treating infectious diseases such as dysentery, bronchitis, eye troubles, conjunctivitis, sinusitis, gonorrhea, and syphilis. Despite its long traditional use in the treatment of infections, this plant is not well studied for its in vitro antimicrobial properties. Therefore, the present study aims to establish the antimicrobial activity profile of extracts from this plant, as well as to isolate and evaluate the antimicrobial activity of the most abundant bioactive compound in C. ferruginea leaves through bioassay-guided purification, using Staphylococcus aureus as a target organism. Although both methanol and water extracts of the plant leaves proved active against S. aureus, a water extract was pursued, and subjected further to liquid-liquid partitioning (ethyl acetate, butanol, and water). The ethyl acetate fraction was found to be the most potent and was subjected to silica gel chromatography. In total, 250 fractions were obtained, and those with similar TLC profiles were clustered into 22 major groups, of which pooled fraction-F6 (83 mg) was the most potent. Additional purification by HPLC resulted in two active peaks, which were identified, using a combination of NMR and mass spectrometry, as hydroquinone and caffeic acid methyl ester. Their antimicrobial activity was confirmed using a microdilution protocol on S. aureus, where hydroquinone had a stronger activity (MIC50 = 63 μg/mL) compared to caffeic acid methyl ester (>200 μg/mL). Traditionally this plant is used as an aqueous preparation to treat many infections, and the present study also demonstrated antimicrobial activity in the aqueous extract, which appears due mainly to two major water-soluble compounds isolated through bioassay-guided purification. This supports the clinical use of the aqueous extract of C. ferruginea leaves as a phytotherapeutic for bacterial infections.

Antioxidant and anti-dermatophytic properties leaf and stem bark of Xylosma longifolium clos

BACKGROUND

The present study was carried out to assess the phytochemical and anti-dermatophytic effect of the leaf and bark extracts of Xylosma longifolium Clos. The leaf and stem bark are used by the indigenous people of Manipur, India for treatment of skin diseases.

METHODS

The leaves and stem barks of Xylosma longifolium were extracted using petroleum ether, chloroform and methanol respectively. The different extracts of each plant parts were tested for antioxidant activity using DPPH assay. The phenolic content was assayed using Folin-Ciocalteu colorimetric method. Each extracts was further analysed by RP-HPLC to quantify some individual flavonoid components. The anti-dermatophytic activity was evaluated both by agar diffusion method and micro wells dilution method against the Microsporum boullardii MTCC 6059, M. canis (MTCC 2820 and MTCC 32700), M. gypseum MTCC 2819, Trichophyton ajelloi MTCC 4878, T. rubrum (MTCC 296 and MTCC 3272).

RESULTS

The free radical scavenging activity values were ranged from 0.7 to 1.41 mg/ml and 0.6 to 1.23 mg/ml, respectively for leaf and stem bark extracts. The amount of total phenolic contents of the extracts occurred in both leaf and bark in the range of 12 to 56.6 mg GAE/100 g and 16 to 58 mg GAE/100 g respectively. RP-HPLC analysis for flavonoids revealed the presence of two major flavonoid compounds, rutin and catechin. Kaempferol was in trace or absent. Methanol leaf extract showed significant low inhibitory effect against tested fungus Trichophyton ajelloi MTCC 4878 (0.140625 mg/ml) as the most sensitive. These finding suggest that the methanol leaf extract tested contain compounds with antimicrobial properties.

CONCLUSION

The results of our study may partially justify the folkloric uses on the plant studied and further provide an evidence that the leaf extract of Xylosma longifolium might be indeed a potential sources of antimicrobial agents.

Sesquiterpenes and other constituents from Dendranthema zawadskii var. latilobum

Six new germacranolides, zawadskinolides A-F (1-6), and a new eudesmane glucoside, chrysantiloboside (7) were isolated from the aerial parts of Dendranthema zawadskii var. latilobum, along with thirteen known constituents. Their structures were elucidated by means of spectroscopic evidence. Bioassay showed that flavonoids such as apigenin (9), (-)-eriodictyol (10) and nepetin (12), as well as the sesquiterpene lactone, zawadskinolide F (6), inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells with IC50 values of 66.15, 132.55, 35.44, and 91.32 μM, respectively.

Flavonol glycosides from Cardamine komarovii

Two new flavonol glycosides (1 and 2) were isolated from a MeOH extract of the aerial parts of Cardamine komarovii Nakai (Cruciferae) together with 13 known phenolic compounds (3–15). The structures of 1 and 2 were determined by spectroscopic methods including 1D and 2D NMR (COSY, HMQC, HMBC, NOESY, and TOCSY) and HR-FAB-MS data.

Two New Alkylresorcinols from Homalomena wendlandii and Their Cytotoxic Activity

In the course of our search for antineoplasic agents from Panamanian Flora, two new alkylresorcinols: 1-(2,6-dihydroxyphenyl)octan-1-one (1) and (+)-1-(3-(1-(2,6-dihydroxyphenyl)butyl)-2,6-dihydroxyphenyl)octan-1-one (2), together with three known compounds, (1 R, 2 R)-1-(benzo[ d][1,3]dioxol-5-yl)propane-1,2,3-triol (3), (+)-aptosimon (4) and (-)-sesamin (5), were identified from the leaves of Homalomena wendlandii Schott (Araceae). Their structures were established by 1D and 2D NMR and IR spectroscopic, and MS methods. Compound 2 exhibited IC50 values of 3.3, 5.8 and 4.0 μg/mL against MCF-7, SF-268 and H-460 cancer human cell lines, respectively.

Flavonoid analyses and antimicrobial activity of various parts of Phaleria macrocarpa (Scheff.) Boerl fruit

Phaleria macrocarpa (Scheff.) Boerl (Thymelaceae) is commonly known as ‘Crown of God’, ‘Mahkota Dewa’, and ‘Pau’. It originates from Papua Island, Indonesia and it grows in tropical areas. Empirically, it is potent in treating the hypertensive, diabetic, cancer and diuretic patients. It has a long history of ethnopharmacological usage, and the lack of information about its biological activities led us to investigate the possible biological activities by characterisation of flavonoids and antimicrobial activity of various part of P. macrocarpa against pathogenic bacteria and fungi. The results showed that kaempferol, myricetin, naringin, and rutin were the major flavonoids present in the pericarp while naringin and quercetin were found in the mesocarp and seed. Furthermore, the antibacterial activity of different parts of P. macrocarpa fruit showed a weak ability to moderate antibacterial activity against pathogenic tested bacteria (inhibition range: 0.93–2.17 cm) at concentration of 0.3 mg/disc. The anti fungi activity was only found in seed extract against Aspergillus niger (1.87 cm) at concentration of 0.3 mg/well. From the results obtained, P. macrocarpa fruit could be considered as a natural antimicrobial source due to the presence of flavonoid compounds.

Antimicrobial Phenolic Compounds from Anabasis Aphylla L

Bioassay-guided fractionation of an ethyl acetate extract from the aerial parts of Anabasis aphylla, a Chenopodiaceous species widely distributed in the northwest of China, led to the isolation of six phenolic compounds, which were identified by means of spectrometric analysis as 1-(2-hydroxy-4,6-dimethoxyphenyl)-ethanone (1), 3,4-dihydroxy cinnamic acid tetracosyl ester (2), 4-hydroxy-3-methoxy benzoic acid (3), 2-hydroxy benzoic acid (4), 3,4-dihydroxy cinnamic acid methyl ester (5) and 4-hydroxy benzoic acid pentadecane ester (6). These compounds were further screened for their minimum inhibitory concentration (MIC) and median inhibitory concentration (IC50) by use of the microdilution-MTT assay for antimicrobial activity against one Gram-positive bacterium ( Bacillus subtilis), three Gram-negative bacteria ( Agrobacterium tumefaciens, Pseudomonas lachrymans, and Xanthomonas vesicatoria), and one yeast ( Candida albicans). Apart from compound 6, which had no activity against any of the tested microorganisms, the other compounds showed selective inhibitory activity. This is the first report on the antimicrobial activity of the phenolic compounds isolated from A. aphylla. The obtained results provide promising baseline information for the potential use of the extract and some isolated compounds from this plant as antimicrobial agents to control plant and animal diseases.