Antibacterial cotton fabrics with in situ generated silver and copper bimetallic nanoparticles using red sanders powder extract as reducing agent

Using aqueous extraction of red sanders powder as a reducing agent, silver and copper bimetallic nanoparticles were in situ generated in cotton fabrics. Silver and copper nanoparticles were also generated separately for comparison. The resulted nanocomposite cotton fabrics (NCFs) were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and antibacterial tests. SEM analysis indicated the generation of more number of nanoparticles when bimetallic source solutions were used. Further, the size range of the generated bimetallic nanoparticles was found to be lower than when individual metal nanoparticles were generated in NCFs. XRD analysis confirmed the in situ generation of silver and copper nanoparticles when equimolar bimetallic salt source solutions were utilized. The NCFs with bimetallic nanoparticles exhibited higher antibacterial activity against both Gram-negative and Gram-positive bacteria and hence can be considered for applications as antibacterial bed and dressing materials.     

Chemical diversity and anti-acne inducing bacterial potentials of essential oils from selected Elsholtzia species

Essential oils from the aerial parts of four Elsholtzia species; Elsholtzia stachyodes, Elsholtzia communis, Elsholtzia griffithii and Elsholtzia beddomei were obtained by steam distillation and their chemical components were analysed by gas chromatography-mass spectrometry (GC-MS). Principle Component Analysis was used to identify the chemical variations in the essential oils from these plants, which could be categorised into two groups according to their main chemical components which are acylfuran derivatives and oxygenated monoterpenes. Additionally, the anti-acne inducing bacterial activity against Staphylococcus aureus and Staphylococcus epidermidis were evaluated. The oil from E. stachyodes was the most efficacious against the growth of S. aureus and S. epidermidis having MIC values of 0.78 and 1.56 μL/mL, respectively, and exhibited five times more effective than erythromycin (standard antibiotic).     

Antimalarial and cytotoxic activities of pregnene-type steroidal alkaloids from Holarrhena pubescens roots

The phytochemical investigation of an alkaloidal extract of Holarrhena pubescens roots led to the isolation and identification of a new pregnene-type alkaloid, mokluangin D (1), together with nine known steroidal alkaloids (2–10). The structure of the new metabolite was determined on the basis of spectroscopic analyses including 1D- and 2D-NMR spectroscopy and mass spectrometry. Compounds 3 and 4 showed potent antimalarial activity against Plasmodium falciparum K1 stain with IC₅₀ values of 1.2 and 2.0 μM, respectively, and showed weak cytotoxic activity against the NCI-H187 cell line with IC₅₀ values of 27.7 and 30.6 μM, respectively. The substituent groups at C-3 and the carbonyl group at C-18 are important for the activity against the P. falciparum K1 stain.     

Nucleoside alkaloids with anti-platelet aggregation activity from the rhizomes of Ligusticum striatum

Two new (1–2) and six known (3–8) nucleoside alkaloids were isolated from the rhizomes of Ligusticum striatum DC. Compounds 1 and 2 (liguadenosines A and B) were unusual N-10 substituted adenosine derivatives. Their structures were elucidated by extensive spectroscopic analyses and ECD calculation. Most of them significantly inhibited the abnormal increase in platelet aggregation induced by ADP at concentrations of 50 and 100 μM. Particularly, the inhibitory effect of 3 was equivalent to aspirin.     

Monanchoxymycalin C with anticancer properties,new analogue of crambescidin 800 from the marine sponge Monanchora pulchra

A new pentacyclic guanidine alkaloid, monanchoxymycalin C (1) was isolated from a new collection of marine sponge Monanchora pulchra along with the known monanchoxymycalin A (2). The structure of 1 was elucidated on the basis of spectroscopic data. Monanchoxymycalin C exhibits cytotoxic activity against human cancer HeLa cells at low micromolar concentrations, induces apoptosis-related death of malignant cells and inhibits cancer cell colony formation. In addition, synergistic and additive effects have been observed in combination with cisplatin.     

Purification and identification of 4-allylbenzene-1,2-diol: an antilisterial and biofilm preventing compound from the leaves of Piper betle L. var Pachaikodi

Antibiotic-resistant food-borne Listeriosis has been rising with up to 30% mortality threat in humans since several decades. Hence, discovering antilisterial from the extracts of ethnomedicinal plants may be of value as a novel antidote. In our preceding study, we reported that ethanolic extract of Piper betle L. var Pachaikodi leaves exhibited antibacterial activity towards Listeria monocytogenes MTCC 657. Consequently in the present study, the bioactive molecule responsible for anti-Listeria activity was purified and identified as 4-allylbenzene-1,2-diol. This identified bioactive compound may have significance while used as antimicrobials and/or food additives in food processing sector as evidenced by dual action: biofilm inhibition and pore formation on cell membrane.     

Analysis and evaluation of the antimicrobial and anticancer activities of the essential oil isolated from Foeniculum vulgare from Hamedan,Iran

In this study, biological properties of the essential oil isolated from seeds of Foeniculum vulgare (F. vulgare) were evaluated. GC-MS analysis revealed Trans-Anethole (80.63%), L-Fenchone (11.57%), Estragole (3.67%) and Limonene (2.68%) were the major compounds of the essential oil. Antibacterial activity of the essential oil against nine Gram-positive and Gram-negative strains was studied using disc diffusion and micro-well dilution assays. Essential oil exhibited the antibacterial activity against three Gram-negative strains of Pseudomonas aeruginosa, Escherichia coli, and Shigella dysenteriae. The preliminary study on toxicity of seed oil was performed using Brine Shrimp lethality test (BSLT). Results indicated the high toxicity effect of essential oil (LC50 = 10 μg/mL). In vitro anticancer activity of seed oil was investigated against human breast cancer (MDA-Mb) and cervical epithelioid carcinoma (Hela) cell lines by MTT assay. Results showed the seed oil behave as a very potent anticancer agent with IC50 of lower than 10 μg/mL in both cases.     

Mangostanaxanthone VIII,a new xanthone from Garcinia mangostana and its cytotoxic activity

A new prenylated xanthone, mangostanaxanthone VIII (7) and six known metabolites: gartanin (1), 1,3,8-trihydroxy-2-(3-methyl-2-butenyl)-4-(3-hydroxy-3-methylbutanoyl)-xanthone (2), rubraxanthone (3), 1,3,6,7-tetrahydroxy-8-prenylxanthone (4), garcinone C (5), and xanthone I (9-hydroxycalabaxanthone) (6) were separated from the EtOAc-soluble fraction of the air-dried pericarps of Garcinia mangostana (Clusiaceae). Their structures have been verified on the basis of spectroscopic data analysis as well as comparison with the literature. The cytotoxic activity of 7 was assessed against MCF7, A549, and HCT116 cell lines using sulforhodamine B (SRB) assay. Compound 7 showed significant cytotoxic potential against MCF7 and A549 cell lines with IC₅₀s 3.01 and 1.96 μM, respectively compared to doxorubicin (0.06 and 0.44 μM, respectively). However, it exhibited moderate activity towards HCT116 cell line.     

Isolation and antiproliferative activity of triterpenoids and fatty acids from the leaves and stem of Turraea vogelii Hook. f. ex benth

Chloroform extract from the leaves of Turraea vogelii Hook f. ex Benth demonstrated cytotoxic activity against a chronic myelogenous leukemia cell, K-562 with IC₅₀ of 14.27 μg/mL, while chloroform, ethyl acetate and methanol extracts from the stem of the plant inhibited K-562 cells growth with IC₅₀ of 19.50, 24.10 and 85.40 μg/mL respectively. Bioactive chloroform extract of Turraea vogelii leaves affords two triterpenoids: oleana-12,15,20-trien-3β-ol (1), and oleana-11,13-dien-3β,16α,28-triol (2), with six fatty esters, ethyl hexaeicos-5-enoate (3), 3-hydroxy-1,2,3-propanetriyltris(tetadecanoate) (4), 1,2,3-propanetriyl(7Z,7′Z,7′′Z)tris(-7-hexadecenoate) (5), 1,2,3-propanetriyl(5Z,5′Z,5′′Z)tris(-5-hexadecenoate) (6), 1,2,3-propanetriyltris(octadecanoate) (7), and 2β-hydroxymethyl tetraeicosanoate (8). Tetradecane (9), four fatty acids: hexadecanoic acid (10), tetradecanoic acid (11), (Z)-9-eicosenoic acid (12), and ethyl tetradec-7-enoate (13) were isolated from chloroform extract of Turraea vogelii stem. 1,2,3-propanetriyltris(heptadecanoate) (14), (Z)-9-octadecenoic acid (15) and (Z)-7-tetradecenoic acid (16) were isolated from ethyl acetate extract while (Z)-5-pentadecenoic acid (17) was obtained from methanol extract of the plant stem. Compounds 1, 2, 5, 6, 11, 12, 15, 16 and 17 exhibited pronounced antiproliferative activity against K-562 cell lines.