New constituents of Terminalia alata

The roots of Terminalia alata yielded a new terpene glycoside, 2α, 3β, 19α-trihydroxy-olean-12-en-28-oic acid methylester 3β-O-rutinoside (1), a new flavanone, 8-methyl-5,7,2′, 4′-tetramethoxy-flavanone (2) and a new chalchone glycoside, 2-O-β-glucosyloxy-4,6,2′,4′-tetramethoxychalchone (3).     

Triterpenoid glycoside from the roots of Terminalia alata

The isolation and NMR spectra of the triterpenoidal glycoside, 2alpha,3beta,19alpha-trihydroxyolean-12-en-28-oic acid 3-O-beta-D-galactopyranosyl- (1-->3)-beta-D-glucopyranoside (1), from the roots of Terminalia alata are reported.     

The antifungal constituents from the seeds of Itoa orientalis

Three new phenolic constituents, itolide A (1), itolide B (2), itoside P (3), and 1D-3-deoxy-3-hydroxymethyl-myo-inositol (4), which is described herein for the first time as a natural product, were isolated along with four other known compounds (5 to 8) from the methanol extract of the seeds of Itoa orientalis Hemsl by the activity-guided fractionation. Their structures were determined by spectroscopic means. Compounds 1 to 8 exhibited antifungal activities against Sclerotium rolfsii with IC₅₀ values ranging from 60.12 to 240.00 μM and against Rhizoctonia solani with IC₅₀ values ranging from 45.34 to 233.14 μM, respectively, and compounds 1, 2, 5 exhibited cytotoxic activity against Tn5B1-4 insect cell line with EC₅₀ values of 203.68, 93.41 and 40.37 μM, respectively.     

New constituents from Gliricidia sepium

The heart wood of Gliricidia sepium stem yielded stigmastanol glucoside (1) and 3',4'-dihydroxy-trans-cinnamic acid octacosylester 2, along with three other known constituents.     

New minor constituents from Anethum sowa

A new propiophenone and a biphenyl derivative from the Indian dill (Anethum sowa) are reported.     

Anti-acne activity of tannin-related compounds isolated from Terminalia laxiflora

In our investigation to find out new anti-acne agent, we focused on Terminalia laxiflora Engl & Diels (Combretaceae) methanolic wood extract, which has been selected during previous screening experiments for anti-acne agents, which included 29 species of Sudanese medicinal plants. Based on the biologically guided fractionation using an antibacterial assay against Propionibacterium acnes, a lipase inhibitory assay and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity assay; five tannin-related compounds were isolated, such as ellagic acid, flavogallonic acid dilactone, terchebulin and gallic acid. Terchebulin showed good antibacterial activity; minimum inhibitory concentration (MIC) = 125 μg/ml and minimum bactericidal concentration (MBC) = 250 μg/ml. Gallic acid exhibited lipase inhibitory activity with IC₅₀ value of 149.3 μM, which showed strong inhibition compared with terchebulin, IC₅₀ 260.7 μM. However, all compounds exhibited better or equal DPPH radical scavenging activity to (+)-catechin as positive control. Ellagic acid and terchebulin showed the best DPPH radical scavenging activities, IC₅₀ 4.86 and 4.90 μM, respectively. This study demonstrated that terchebulin has potentiality as an anti-acne agent.     

A new cardenolide from the seeds of Terminalia bellerica

A new cardenolide, cannogenol 3-O-beta-D-galactopyranosyl-(1-->4)-O-alpha-L-rhamnopyranoside (1), was isolated form the seeds of Teminalia bellerica.     

A new cardenolide from the roots of Terminalia arjuna

A new cardenolide, 16,17-dihydroneridienone 3-O-beta-D-glucopyranosyl-(1-->6)-O-beta-D-galactopyranoside (1), was isolated from the roots of Terminalia arjuna.     

Antibacterial activity of Terminalia pallida

The methanol extract of the dried fruit powder of Terminalia pallida was evaluated for antimicrobial activity. The methanol extract showed a broad spectrum of antibacterial activity.     

Antifungal activity of Terminalia australis

Dichloromethane, methanol and aqueous extracts of the aerial parts of Terminalia australis were evaluated for their antifungal activity. The methanol and aqueous extracts were found to be effective against the tested Aspergillus and Candida strains.     

New sources and antifungal activity of sesquiterpene lactones.

In the search for new sources of sesquiterpene lactones, six Centaurea species have been analyzed. The activity against the fungus Cunninghamella echinulata of (+)-cnicin (1) and (+)-salonitenolide (2), isolated from the Centaurea plants, as well as that of (+)-costunolide (3), (-)-dehydrocostuslactone (4), (-)-lychnopholide (5) and (-)-eremantholide C (6), has been evaluated. Compounds 3 and 4 showed noticeable EC50 values, whilst more polar lactones were inactive. These results suggest that a relatively low polarity is one of the molecular requirements for the antifungal activity of sesquiterpene lactones.     

Chemical constituents from Asparagus dumosus

The isolation and characterization of calonysterone (1), blechnoside B (2), 20-hydroxyecdysone and isovanillin from the whole plant of Asparagus dumosus are being reported for the first time from this source.     

Cytotoxic constituents from Plumbago zeylanica

The bioassay-guided fractionation of the dichloromethane extract of aerial parts of Plumbago zeylanica led to the isolation of beta-sitosterol, beta-sitosteryl-3beta-glucopyranoside, beta-sitosteryl-3beta-glucopyranoside-6'-O-palmitate (1), lupenone, lupeol acetate, plumbagin and trilinolein. Compound 1 showed cytotoxic activity against MCF7 and Bowes cancer cell lines (IC50 113 microM and 152 microM, respectively), beta-sitosterol inhibited Bowes cell growth (IC50 36.5 microM) and plumbagin was cytotoxic against MCF7 and Bowes cells (IC50 1.28 microM and 1.39 microM, respectively).     

Hepatitis C virus inhibitory hydrolysable tannins from the fruits of Terminalia chebula

Two new hydrolysable tannins, chebumeinin A (1) and chebumeinin B (2), together with eight known related compounds (3-10), were isolated from the fruits of Terminalia chebula. The new compounds were structurally determined by analysis of their spectroscopic data and the known compounds characterized by comparing their spectroscopic data with literature values. All isolates were evaluated by an HCV protease inhibition assay, and some compounds were found to be potently active.     

Anti-neuroinflammatory constituents from Asparagus cochinchinensis

Three new pregnane glycosides, aspacochinosides N (1), O (2), and P (3) were isolated from the roots of Asparagus cochinchinensis, together with four known furostanol glycosides. Their structures were determined by chemical methods and NMR spectral analysis, including extensive 1D and 2D NMR experiments. Compounds 1–7 were evaluated for their anti-neuroinflammatory activity in LPS-induced BV-2 microglial cells. Compounds 2, 3, and 4 showed significant inhibition on NO production in LPS-induced BV-2 microglial cells with IC₅₀ values of 13.51, 4.72, and 63.57 μM, respectively.     

Chemical constituents from Tillandsia recurvata

The CHCl3 extract of Tillandsia recurvata yielded 5,3'-dihydroxy-6,7,8,4'-tetramethoxyflavanone (1), 1,3-di-O-cinnamoyl-glycerol (2) and ethyl ester of caffeic acid. Their structures were elucidated by means of spectroscopic methods such as mass spectroscopy and 1 and 2D-NMR.     

Chemical constituents from Aphanamixis grandifolia

Four new terpenoids, nemoralisins D–G (1–4), were isolated from the leaves and stems of Aphanamixis grandifolia, along with two known diterpenoids, nemoralisin C and nemoralisin. Among them, compound 1 is the first example of norsesquiterpenoid with δ-lactone moiety, and nemoralisins E–G (2–4), are a class of acyclic diterpenoids, which are structurally related nemoralisin C and nemoralisin. These structures were established on the basis of spectroscopic methods and the absolute configuration of 1 was determined by comparison of quantum chemical TDDFT calculated and experimental ECD spectra. Nemoralisins D–G (1–4) were tested for their cytotoxicities on HL-60, SMMC-7721, A-549, MCF-7, and SW480 human tumor cell lines (IC₅₀ > 40 μM), as well as the antimicrobial activities on Staphylococcus aureus, Pseudomonas aeruginosa, MRSA92^# and MRSA98^# (MIC > 50 μg/mL).     

A new antifungal coumarin from Clausena excavata

A new γ-lactone coumarin, named as excavarin-A, showing antifungal activity was isolated from the leaves of Clausena excavata by bioassay guided fractionation method. The structure was elucidated by spectroscopic data analysis and identified as 7((2E)-4(4,5-dihydro-3-methylene-2-oxo-5-furanyl)-3-methylbut-2-enyloxy) coumarin. Minimum inhibitory concentration (MIC) was determined against fifteen fungal strains pathogenic against plants and human. The least MIC was recorded against the human pathogen, Candida tropicalis and the plant pathogens Rhizoctonia solani and Sclerotinia sclerotiorum. Antifungal activities against the human pathogens, Aspergillus fumigatus and Mucor circinelloides and plant pathogens, Colletotrichum gloeosporioides, Lasiodiplodia theobromae, Fusarium oxysporum and Rhizopus stolonifer were stronger than that of the standard antimicrobials.     

Antimicrobial activity of Cassia alata.

The methanol extracts of leaves, flowers, stem and root barks of Cassia alata showed a broad spectrum of antibacterial activity. The activity was increased on fractionation (petrol, dichloromethane, ethyl acetate), the dichloromethane fraction of the flower extract being the most effective. No activity was shown against tested moulds.     

Chemical constituents from the linseed meal

One megastigmane derivative 1, one methyl jasmonate glycoside derivative 2, and two C-28 steroids with 3β,5β-cis-dihydroxyl conformation 3 and 4, together with eight known compounds 5–12 were isolated from the 70% ethanol extract of linseed meal (Linum usitatissimum L). Structures of 1–4 were elucidated by spectroscopic methods including NMR, HRESIMS, and Mo₂(OAc)₄-induced CD. The absolute configuration of 1 and 3 was determined by observing their induced circular dichroism after addition of Mo₂(OAc)₄ in DMSO. The absolute configuration of 2 was determined by NOESY experiment together with conformational analysis. The structure of 4a was corrected as 4 by an extensive analysis of its 1D and 2D NMR, in combination with the Mo₂(OAc)₄-induced CD in DMSO. The effect of all the isolates on nitric oxide (NO) generation by stimulated macrophages was evaluated, and none of them showed active.