Chemical modification of active scaffolds from natural products has gained interest in pharmaceutical industries. Nevertheless, the metabolites extraction is time-consuming while the lead is frequently mismatched with the receptor. Here, the diazo coupling approach was introduced to generate a series of vanillin derivatives featuring halogenated azo dyes (1a-h). The vanillin derivatives showed effective inhibition of S. aureus (7-9 mm) and E. coli (7-8 mm) compared to the parent vanillin, while 1b had the highest inhibition zone (9 mm) against S. aureus comparable to the reference ampicillin. The presence of N = N, C = O, -OH, -OCH3 and halogens established strategic binding interactions with the receptor. The potential vanillin-azo as an antimicrobial drug was supported by in silico docking with penicillin-binding proteins and DFT (using Gaussian 09) with binding affinity -7.5 kcal/mol and energy gap (Egap) 3.77 eV, respectively. This study represents a significant advancement in drug discovery for effective antibiotics with excellent properties.
The Bombax ceiba L. tree is a member of the family Bombacaceae and the genus Bombax. Both Chinese and Indian traditional medicine have made extensive use of it in the treatment of sickness. Its chemical composition is still a mystery. B. ceiba roots methanol extract (BCRME) was analyzed by different chromatographic analytical techniques in order to identify its major chemical constituents. Twelve compounds and six compounds were identified from GC-MS and LC-MS analysis, respectively. This is the first report on the presence of lathodoratin, cedrene, 4H-1-benzopyran-4-one,8-[{dimethylamino} methyl]-7-methoxy-3-methyl-2-phenyl, asiatic acid, and (E)-2,4,4'-trihydroxylchalcone in B. ceiba roots. Methanol extract demonstrated noteworthy antibacterial activity against Staphylococcus aureus (MTCC96) (MIC: 100 µg/mL) compare to antibiotic ampicillin (MIC: 250 µg/mL) as well as the highest α-amylase inhibition (IC50=26.91 µg/mL) and α-glucosidase inhibition (IC50=21.21 µg/mL) effects, molecular docking study confirmed these findings, with some compounds having a very high docking score.
Previous phytochemical investigations reported that Calophyllum spp have biosynthesized a wide range of bioactive phenolics such as xanthones and coumarins. The phytochemical study conducted on the stem bark of C. canum has led to the isolation of eight trioxygenated xanthones namely: 5-methoxytrapezifolixanthone (1), 5-methoxyananixanthone (2), caloxanthone C (3), 1,5-dihydroxy-3-methoxy-4-isoprenylxanthone (4), 6-deoxyisojacareubin (5), euxanthone (6), trapezifolixanthone (7), ananixanthone (8), together with three common triterpenoids, β-sitosterol (9), friedelin (10), and stigmasterol (11). Furthermore, xanthones 1 and 2 were isolated for the first time as naturally occurring xanthones from the plant extract. The structures of these compounds were identified and elucidated using advanced spectroscopic techniques such as 1 D & 2 D NMR, MS, and FTIR. The neuroprotective property of selected compounds was tested through in vitro stroke model. Among all tested compounds, 1 µm of compounds 8, 9, and 10 showed significant neuroprotective activity via reduction of apoptosis by ∼ 50%.
Cashew (Anacardium occidentale L.) leaf is traditionally used to treat skin infections. Although many flavonols have been identified from its leaf extract, their inhibitory effects on skin pathogens are not yet determined. The aims of this study were to determine the antimicrobial (against skin pathogenic microbes) and antioxidant activities of four flavonol glycosides from the crude extract and three flavonol aglycones from the hydrolyzed extract. The hydrolyzed extract was found to show higher activities than the crude extract. Myricetin showed the highest activity against all the tested bacteria and yeast with the lowest Minimum Inhibition Concentration (MIC) of 7.81 μg/mL on Corynebacterium minutissimum ATCC23348. Myricetin also exhibited good primary antioxidant activities with the effective concentration with 50% of activity (EC50) values ranged between 2.23 μg/mL and 6.40 μg/mL. The highest secondary antioxidant activity was indicated by myricetin-3-O-rhamnoside. Thus, myricetin can be considered as a bioactive compound of the hydrolyzed extract.
This study aimed to assess the antimicrobial activity of endophytic Phyllosticta fallopiae L67 isolated from Aloe vera against diabetic wound microorganisms and characterise their active fraction for biologically important metabolites. The dichloromethane (DCM) extract exhibited the most significant activity with inhibition zones ranging from 11.33 to 38.33 mm. The minimal inhibitory and lethality concentrations of DCM extract ranged from 78.13 to 2500.00 µg/ml and 625.00 to 5000.00 µg/ml, respectively. The extract showed teratogenicity and lethality in the zebrafish model, where peritoneal and hepatic oedema occurred at 62.50 µg/ml, and no abnormality appeared at 31.25 µg/ml. The extract also inhibited more than 82% biofilm formation. Bioassay-guided fractionation on DCM extract yielded 18 fractions and the most active fraction was subjected to UPLC-QTOF-MS/MS analysis. Flavones, stilbenes, flavanonols, isoflavonoids, phenolic glycosides and phenol derivatives were detected. In conclusion, endophytic P. fallopiae possessed bioactive metabolites with significant antimicrobial activity against diabetic wound microorganisms.
In the present research, oleuropein (OLE) contents from two Saudi Arabian wild olive trees (Olea europaea L.) leaves (O1 and O2), were collected from two nearby geographical sites differing in altitudes, and were determined via UHPLC-MS analysis. Moreover, total bioactive contents, antioxidant, and cytotoxicity (against MCF-7 and MDA-MB-231 cells) potential were also evaluated. The sample (O2) was found to contain significantly (p
Liquid Chromatography-Mass Spectrometry (LC-MS) analysis of methanol extract of Martynia annua seed revealed the presence of haploperozide and austricine. For safety, heavy metals content investigation of plant powder using the Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) technique showed that the toxic metals (Pb: 2.07 mg/kg; Cd: 0.07 mg/kg; and As: 0.18 mg/kg) concentrations were found to be below the permissible limit. The extract demonstrated significant antibacterial activity against E. coli (MIC value 125 g/mL). Furthermore, it was effective in inhibiting both α-glucosidase and α-amylase enzymes with a high percentage and IC50 values were 42.28 ± 0.39 µg/mL and 34.11 ± 0.31 µg/mL, respectively. These findings were supported by a molecular docking study, some of the phytochemicals showed higher docking score values than references. However, Martynia annua seeds are safe to consume because they contain low levels of toxic heavy metals and possess antibacterial and anti-diabetic properties.
The genus Knema Lour. is distributed mainly in Southeast Asian and widely used in folk medicine for treating diseases such as jaundice, chronic fever, and inflammation. The chemical composition, acetylcholinesterase inhibition, and molecular docking studies of essential oil from Knema hookeriana Warb. were investigated in this study. The essential oil was achieved through hydrodistillation and was characterised using gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The acetylcholinesterase inhibitory activity was evaluated using Ellman method while molecular docking studies were carried out using Autodock v.4.3.2. The results revealed that the essential oil examined consisted mainly of β-caryophyllene (26.2%), germacrene D (12.5%), δ-cadinene (9.2%), germacrene B (8.8%) and bicyclogermacrene (5.5%). The essential oil showed acetylcholinesterase activity with IC50 value of 70.5 µg/mL. The enzyme-ligand molecular docking study showed that β-caryophyllene and δ-cadinene exhibited good binding affinities towards AChE with docking scores -8.1 kcal/mol and -8.3 kcal/mol, respectively.
This study focused on the synthesis of 1,3-dihydroxyxanthone (1) and its new derivatives with alkyl (2a-2f), alkenyl (2 g-2k), alkynyl (2 l-2n), and alkylated phenyl (2o-2r) groups at C3 position. The structures of these compounds were confirmed by MS, NMR, and FTIR spectroscopic data. All the substituted xanthones (2a-2r) showed significantly stronger acetylcholinesterase (AChE) inhibitory activities than 1. Compounds 2g and 2j exhibited the strongest activities with the IC50 values of 20.8 and 21.5 μM and their enzyme kinetic analyses indicated a mixed-mode inhibition. Molecular docking study revealed that 2g binds favourably to the active site of AChE via π-π stacking and hydrogen bonding from the xanthone ring, in addition to π-alkyl interaction from the substituent group. These xanthone derivatives are potential lead compounds to be further developed into Alzheimer's disease drugs.
Species from the Genus Calophyllum are rich source for bioactive phenolic compounds such as coumarins and xanthones. Phytochemical study carried out on the plant, Calophyllum macrocarpum has led to the isolation of three known prenylated xanthones, ananixanthone (1), trapezifolixanthone (2) and 8-deoxygartanin (3) with two common triterpenoids, stigmasterol (4), and friedelin (5). The structures of these compounds were identified and determined using spectroscopic techniques such as NMR and MS. The cytotoxic activities of compounds 1 and 2 as well as the extracts were tested against HeLa Chang liver and HEK-293 cell lines. Compound 1 exhibited appreciable cytotoxicity with the IC50 value of 11.08 ± 3.09 µM against HeLa Chang liver cell line and moderate cytotoxicity against HEK-293 cell line while compound 2 showed limited toxicity against these two cell lines.
This study aimed to compare the total phenolic (TPC), flavonoid (TFC), radical scavenging and cytotoxic activities in the aqueous methanolic extracts of Angelica sinensis, Dioscorea polystachya, Ginkgo biloba, Glycyrrhiza uralensis and Lycium barbarum with two dietary plants: Brassica oleracea and Zingiber officinale. The TPC and TFC in medicinal plant extracts were 12-93% lower than Z. officinale as follows: L. barbarum > G. uralensis > A. sinensis > G. biloba > D. polystachya. The decreasing radical scavenging activity in medicinal plant extracts shared similar trend: G. uralensis > L. barbarum > A. sinensis > G. biloba > D. polystachya. Both TPC and TFC were positively correlated with radical scavenging and cytotoxic activities. All medicinal plants were considered inactive (LC50 > 0.2 mg/ml) and safe for consumption. The TPC, TFC, radical scavenging and cytotoxic activities in the medicinal plants were plant-part dependant, in particular L. barbarum and G. uralensis.
The red alga Chondria armata is known to produce and contain a rich diversity of secondary metabolites, such as domoic acid-related alkaloids and triterpene polyethers. Our investigation on red alga C. armata from Kagoshima coast, Japan, resulted in the isolation of two new triterpene polyethers, bandokorols A (1) and B (2). The structures of these compounds were determined based on spectroscopic data such as infrared (FTIR), 1H-NMR, APT, 1H-1H-COSY, HSQC, HMBC, NOESY and FAB mass spectrometry (HRFABMS). The anticancer potentials of these compounds were tested against adult T-cell leukaemia (ATL), S1T cells and their IC50 values are reported here.
The present study was intended to evaluate the in vitro (COX-1/COX-2) and in vivo anti-inflammatory and ulcerogenic activity of newer phytoconstituents isolated from the aerial parts of Swertia alata C.B. Clarke (Gentianaceae). For isolation of newer phytoconstituents, the ethanolic extract of aerial parts of S. alata was subjected to column chromatography using mixture of petroleum ether and chloroform in various concentrations, which yielded two phytoisolates characterised as nonacosyl triacontanoate (SA-3) and 8-O-glucpyranosyl-(2-acetyl)-1,3-dihydroxy-5-methoxy-xanthone (SA-9). Identification of compounds was based on melting point, UV, FTIR, 1H-NMR, 13C-NMR and mass spectrometric data. The isolates were screened for in vitro COX-1/COX-2 inhibitory activity, in vivo anti-inflammatory and ulcerogenic activity. Among the two compounds, SA-3 was found to be more effective than SA-9. The ulcerogenic study revealed significant gastric tolerance of SA-3 and SA-9 in comparison to indomethacin.
Macluraxanthone was previously reported to have many biological activities, including anti-cholinesterase, anti-oxidant, anti-cancer, anti-malarial and anti-inflammatory effects. The aim of the current study was to further characterise the effect of macluraxanthone on human macrophage, a type of immune cell that has been implicated in the development of various inflammatory diseases. The expression of surface markers and cytokine production by THP-1 human macrophages following treatment with macluraxanthone were investigated. Macluraxanthone was shown to promote polarisation of M1-like pro-inflammatory macrophages by increasing the percentage of macrophages expressing CD86, while decreasing their CD14, CD11b and CD80 expression. However, in the presence of the pro-inflammatory stimulus lipopolysaccharide, macluraxanthone significantly decreased TNF-α and IL-10 cytokine production.
Currently, type 2 diabetes mellitus (T2D) has emerged as global burden disease. Herbal drugs with antidiabetic activities are attracting the attention. Madecassoside and catalpol are herbal compounds having strong antioxidant and glucose lowering activity. Madecassoside and catalpol were investigated for their effect on insulin sensitivity using pancreatic INS-1E cells. Cytotoxicity of these compounds was evaluated by MTT assay. Glucose-stimulated insulin secretion (GSIS) and expression of insulin signalling proteins were studied in presence of madecassoside and catalpol. Results revealed that madecassoside and catalpol enhanced the GSIS without cytotoxic effect. Madecassoside (30 µM) and catalpol (40 µM) increased the insulin secretion in response to high glucose (16.7 mM) stimulation. Subsequently, madecassoside and catalpol showed elevated expression of p-IRS-1, Akt, and p-Akt proteins. Madecassoside and catalpol after 24 h of incubation in pancreatic INS-1E cells with high glucose concentration (30 mM) ameliorated the insulin secretion.
Genus Calophyllum from the family of Calophyllaceae is an evergreen broad-leaved tree that is endemic to Southeast Asia, especially Malaysia. They have been reported for various ethnomedicinal uses in traditional medicine. Previous studies of Malaysian Calophyllum species revealed them to be a rich source of bioactive phytoconstituents such as xanthones, coumarins, terpenoids, and chromanone acids. To date, the extracts and compounds from Malaysian Calophyllum species have shown a broad spectrum of pharmacological activities. For example, calanolide A, a coumarin isolated from Malaysian C. lanigerum, has now reached clinical development to become an anti-HIV drug. This article presents an overview of the significant phytochemical and pharmacological activities of Malaysian Calophyllum species to aid researchers in further discovery of potential benefits of various species of this genus.
A new cycloartane triterpene bisdesmoside, soulieoside T (1), and one known compound, oleanolic acid (2), were isolated from the ethanolic extract of the rhizomes of Actaea vaginata. Their structures were elucidated by spectroscopic methods and by comparison with data reported in the literature. Compound 1 was evaluated for cytotoxic activities against three human cancer cell lines.
Phytochemical investigation on the soluble fractions of n-hexane and dichloromethane of methanolic leaves extract of the Callicarpa maingayi K. & G. led to the isolation of three triterpenoids [euscaphic acid (1), arjunic acid (2), and ursolic acid (3)] together with two flavones [apigenin (4) and acacetin (5)], two phytosterols [stigmasterol 3-O-β-glycopyranoside (6) and sitosterol 3-O-β-glycopyranoside (7)], and a fatty acid [n-hexacosanoic acid (8)]. Six (6) compounds (1, 2, 3, 4, 5, and 8) are reported for the first time from this species. Their structures were elucidated and identified by extensive NMR techniques, GC-MS and comparison with the previously reported literature. Compound 3 was found to displayed good inhibition against acetylcholinesterase with an IC50 value of 21.5 ± 0.022 μM, while 1 and 2 exhibited pronounced α-glucosidase inhibitory activity with IC50 values of 22.4 ± 0.016 μM and 24.9 ± 0.012 μM, respectively.
Rhizomes of Curcuma caesia are traditionally used to treat cancer in India. The aim is to isolate chemical constituents from C. caesia rhizomes through bioassay-guided fractionation. The extract, hexanes and chloroform fractions showed effect on MCF-7 and MDA-MB-231cells in cell viability assay. The chromatographic separation afforded germacrone (1), zerumbone (2), furanodienone (3), curzerenone (4), curcumenol (5), zederone (6), curcumenone (7), dehydrocurdione (8) from hexanes fraction and curcuminol G (9), curcuzederone (10), (1S, 10S), (4S,5S)-germacrone-1 (10), 4-diepoxide (11), wenyujinin B (12), alismoxide (13), aerugidiol (14), zedoarolide B (15), zedoalactone B (16), zedoarondiol (17), isozedoarondiol (18) from chloroform fraction. This is first report of compounds 2, 9-13, 15-18 from C. caesia. The study demonstrated compounds 1-4 and 10 are the bioactive compounds. The effect of curcuzederone (10) on MDA-MB-231 cell migration showed significant inhibition in scratch and Transwell migration assays. The results revealed that curcuzederone could be a promising drug to treat cancer.
One new sesquiterpene dilactone, coccinine (1) and one new β-carboline alkaloid, daibucarboline F (2) together with 10 known compounds; linderane (3), linderalactone (4), pseudoneolinderane (5), linderanlide C (6), linderanine A (7), epicatechin (8), (-)-taxifolin (9), astilbin (10), L-quercitrin (11) and afzelin (12) were isolated from the stems and leaves of Neolitsea cassia (L.) Kosterm (Lauraceae). The structures of (1 and 2) were established by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in literature. The relative stereochemistry of compound (1) was assigned by X-ray diffraction analysis with Cu-Kα irradiation. Compounds (3-8) and (10) were evaluated for their α-glucosidase enzymatic inhibitory activity. Compounds (4-6), (8) and (10) exhibited inhibition towards α-glucosidase enzymatic activity with IC50 values ranging from 12.10 to 96.77 μM. This is the first report on the isolation of phytochemicals from N. cassia and their bioactivities.