Antibacterial carbazole alkaloids from Clausena harmandiana twigs

Three new carbazole alkaloids, harmandianamines A-C (1-3), together with fifteen known compounds (4-18) were isolated from the twigs of Clausena harmandiana. The structures were elucidated by spectroscopic methods, including UV, IR, NMR, and MS. The antibacterial activity against Escherichia coli TISTR 780, Salmonella typhimurium TISTR 292, Staphylococcus aureus TISTR 1466 and methicillin-resistant S. aureus (MRSA) SK1 of some isolated compounds was also evaluated. Compound 6 exhibited significant antibacterial activity against MRSA SK1 with an MIC value of 0.25 μg/mL which higher than that of standard drug, vancomycin (MIC value=1 μg/mL) whereas compounds 14 and 5 showed strong activity with MIC values of 4 and 8 μg/mL, respectively. Only compound 14 showed strong antibacterial activity against S. aureus TISTR 1466 with an MIC value of 4 μg/mL.     

Antibacterial dihydrobenzopyran and xanthone derivatives from Garcinia cowa stem barks

Two new compounds, garciniacowol (1) and garciniacowone (2) along with 15 known compounds were isolated from the stem barks of Garcinia cowa. Their structures were determined by intensive spectroscopic methods. The structure of 1 was a symmetrical dimeric dihydrobenzopyran derivative, whereas the framework of 2 was a triprenyl caged-xanthone precursor. The antibacterial activities against Escherichia coli TISTR 780, Salmonella typhimurium TISTR 292, Staphylococcus aureus TISTR 1466, and methicillin-resistant S. aureus (MRSA) SK1 of the isolated compounds were also evaluated. Compounds 2 and 9 exhibited good antibacterial activity against MRSA SK1 with the same minimum inhibitory concentration (MIC) value of 2 μg/mL. Moreover, compound 2 also showed good antibacterial activity against S. aureus with an MIC value of 2 μg/mL.     

Three new antibacterial active diarylheptanoids from Alpinia officinarum

Three new diarylheptanoids, together with ten known ones, were isolated from the ethanol extract from the rhizomes of Alpinia officinarum Hance. The structural identification of these compounds was mainly achieved by spectroscopic methods. The new compounds were elucidated as 7-(4″, 5″-dihydroxy-3″-methoxyphenyl)-1-phenyl -4-heptene-3-one (1), 1, 7-diphenyl-5-heptene-3-one (2) and 4-phenethyl-1, 7-diphenyl -1-heptene-3, 5-dione (3), respectively. All of the compounds showed antibacterial activity against Helicobactor pylori. Especially, the three new compounds showed strong antibacterial activity against Hp-Sydney strain 1 with the MIC values of 9–12 μg/mL, and against Hp-F44 with the MIC values of 25–30 μg/mL.     

Steroids with inhibitory activity against the prostate cancer cells and chemical diversity of marine alga Tydemania expeditionis

A new diketosteroid, (E)-stigmasta-24(28)-en-3,6-dione (1), along with three known steroids (2-4) was isolated from marine alga Tydemania expeditionis collected in China Sea. Their structures were elucidated by extensive spectroscopic methods. Comparison of the chemical constituents revealed significant diversity among different locations. The biological activities of 1, 3 and 4 were evaluated on the prostate cancer cell lines and androgen receptor. Compound 1 exhibited moderate inhibitory activities against the prostate cancer cells DU145, PC3 and LNCaP with IC(50) values of 31.27±1.50, 40.59±3.10 and 19.80±3.84 μM, respectively. Compound 3 showed more potent activities with IC(50) values of 12.38±2.47, 2.14±0.33 and 1.38±0.07 μM, respectively. However, compound 4 showed only weak inhibitory activities on LNCaP cells and was inactive on DU145 and PC3 cells. A competitive binding assay showed that compound 1 exhibited significant affinity to the androgen receptor with an IC(50) value of 7.19±0.45 μM, while 3 and 4 were inactive. The fact that the inhibitory properties of 1 and 3 against the prostate cancer cells were inconsistent with their affinities to the androgen receptor suggested that there might be other mechanism of action involved in the cytotoxic activity.     

Antibacterial anthranilic acid derivatives from Geijera parviflora

Five anthranilic acid derivatives, a mixture I of three new compounds 11′-hexadecenoylanthranilic acid (1), 9′-hexadecenoylanthranilic acid (2), and 7′-hexadecenoylanthranilic acid (3), as well as a new compound 9,12,15-octadecatrienoylanthranilic acid (4) together with a new natural product, hexadecanoylanthranilic acid (5), were isolated from Geijera parviflora Lindl. (Rutaceae). Their structures were elucidated by extensive spectroscopic measurements, and the positions of the double bonds in compounds 1–3 of the mixture I were determined by tandem mass spectrometry employing ozone-induced dissociation. The mixture I and compound 5 showed good antibacterial activity against several Gram-positive strains.     

Antibacterial effect of Dryopteris crassirhizoma against methicillin-resistant Staphylococcus aureus

Methanol extract and its fractions (hexane, EtOAc, n-BuOH, and H2O) of Dryopteris crassirhizoma were investigated for antibacterial activity against methicillin-resistant Staphylococcus aureus. The hexane fraction showed a good antibacterial activity against all tested strains.     

Gelam honey inhibits lipopolysaccharide-induced endotoxemia in rats through the induction of heme oxygenase-1 and the inhibition of cytokines, nitric oxide, and high-mobility group protein B1

Malaysian Gelam honey has anti-inflammatory and antibacterial properties, a high antioxidant capacity, and free radical-scavenging activity. Lipopolysaccharide (LPS) stimulates immune cells to sequentially release early pro- and anti-inflammatory cytokines and induces the synthesis of several related enzymes. The aim of this study was to investigate the effect of the intravenous injection of honey in rats with LPS-induced endotoxemia. The results showed that after 4h of treatment, honey reduced cytokine (tumor necrosis factor-α, interleukins 1β, and 10) and NO levels and increased heme oxygenase-1 levels. After 24h, a decrease in cytokines and NO and an increase in HO-1 were seen in all groups, whereas a reduction in HMGB1 occurred only in the honey-treated groups. These results support the further examination of honey as a natural compound for the treatment of a wide range of inflammatory diseases.     

A new neuroprotective bakkenolide from the rhizome of Peatasites tatewakianus

Constituents of the fruits of Peatasites tatewakianus were investigated. A new compound, namely bakkenolide-VI (1), was isolated. The structures was elucidated on the basis of 1D, 2D NMR, TOF-MS and ESI-MS techniques, and physicochemical properties. The neuroprotective activity of the new compound was assayed with primary cultured neurons exposed to oxygen-glucose deprivation and oxidative insults.     

A new asymmetric diamide from the seed cake of Jatropha curcas L.

A new asymmetric diamide (E)-N-(3-acetamidopropyl)-cinnamamide named curcamide (1) has been isolated from the ethanol extract of the seed cake of Jatropha curcas L. along with 7 known compounds identified as isoamericanin (2), isoprincepin (3), caffeoylaldehyde (4), isoferulaldehyde (5), glycerol monooleate (6), syringaldehyde (7), and β-ethyl-d-glucopyranoside (8). The synthesis and antibacterial activity of the new compound have been also studied.     

New antibacterial triterpenoid saponin from Lactuca scariola

A new antibacterial triterpenoid saponin, 3beta-O-[alpha-L-rhamnopyranosyl]-30-norolean-12,19-diene-28-oic acid 28-O-[beta-D-glucopyranosyl-(1-->4)-O-beta-D-galactopyranosyl]-ester (1); has been isolated from the stems of Lactuca scariola. Its structure was determined by chemical degradations and spectral analysis.     

Bisindole alkaloids and secoiridoids from Alstonia macrophylla Wall. ex G. Don

The ethanolic extract from stems of a Thai medicinal plant, Alstonia macrophylla Wall. ex G. Don (Apocynaceae) showed a significant inhibitory effect on acetylcholinesterase (AChE) determined by using Ellman assay. Four compounds i.e., a bisindole alkaloid, macralstonine (1), a new bisindole alkaloid, thungfaine (2), a secoiridoid glycoside, sweroside (3) and a new secoiridoid glycoside, naresuanoside (4) were isolated. Compound 4 showed moderate AChE and butyrylcholinesterase (BChE) inhibitory effects. Interestingly, compound 4 inhibited cell growth on human androgen-sensitive prostate cancer cell line (LNCaP) but no effect on viability of human foreskin fibroblast cells (HF).     

Biologically active steroids from the aerial parts of Vernonia anthelmintica Willd

A new steroid, vernoanthelsterone A (1), and five known steroids were isolated from the aerial parts of Vernonia anthelmintica Willd. Compound 1 possesses a Δ(8(14))-15-one moiety. To our best knowledge, few steroids with this moiety have been reported before. Compounds 1-6 were tested for their antibacterial activities and their effects on estrogen biosynthesis in human ovarian granulosa-like cells (KGN cells). Compound 2 showed the ability to promote estrogen biosynthesis with EC(50) of 56.95 μg/mL and also exhibited the antibacterial activities against Bacillus cereus, Staphyloccocus aureus, Bacillus subtilis and Escherichia coli with MICs ranging from 3.15 to 15.5 μg/mL. The structures of 1-6 were determined on the basis of IR, MS, 1D and 2D NMR.     

Antibacterial activity of plant extracts from Brazilian southeast region

A screening was conducted with 26 plants collected in the Brazilian southeast region, to identify plant extracts with antibacterial properties against Aeromonas hydrophila, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus. Initially, the agar diffusion method was employed. Then, those extracts presenting activity were submitted to a broth microdilution assay to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). It was observed that 13 of the tested extracts showed antibacterial activity. The best results were obtained with those from Lantana lilacina and Phyllanthus tenellus.     

A new dihydrodibenzodioxinone from Hypericum x ‘Hidcote’

One new compound, 4-hydroxy-4a,7-dimethoxy-4,4a-dihydrodibenzo-p-dioxin-2(3H)-one (1), was isolated from the aerial parts of the hybrid Hypericum x ‘Hidcote’, together with 8 known compounds: caryophyllene-4,5-epoxide, quercetin, quercitrin, quercetin-3-O-β-D-galactopyranoside, epicatechin, betulinic acid methyl ester, β-sitosterol and β-sitosterol glucoside. The structure of the new compound, as well as its absolute configuration, was established by means of spectroscopic data analyses, including 2D NMR spectroscopy and X-ray structural analysis.     

Bioactive polar compounds from stem bark of Magnolia officinalis

Two new phenylethanoid glycosides magnoloside D (1) and E (2), together with nine known compounds, were isolated from the polar part of methanol extract of the stem bark of Magnolia officinalis. The structures of the new compounds were established on the basis of spectral analysis. Anti-spasmodic activity of four major constituents (3, 4, 9 and 11) was tested in isolated colon of rat, compounds 3, 4, and 9 showed inhibition against acetylcholine, with the effect similar to that of magnolol and honokiol. At the same time, antioxidant activity of the isolated compounds was investigated using a DPPH and an ORAC assay. All of the compounds, except compound 8 showed potent antioxidant capacity in the ORAC assay, while compounds 1-5 and 11 exhibited potent antioxidant activity in the DPPH assay.     

防霉抗菌软木地板的制备与性能研究

为了制备具有防霉抗菌功能的环保型软木地板，在水性涂料面漆中加入纳米银抗菌剂和二氧化钛载银抗菌剂，分析抗菌剂类型和添加量对地板性能的影响。结果表明：抗菌剂的加入对软木地板的物理性能无明显影响，但可以有效提高其抗菌性能，且对金黄色葡萄球菌的抑制效果显著优于大肠杆菌；软木本身具有一定的防霉作用，纳米银抗菌剂和二氧化钛载银抗菌剂防霉作用较弱，可通过加入少量防霉剂提高软木地板防霉性。     

Aromatic compounds from endophytic fungus Colletotrichum sp. L10 of Cephalotaxus hainanensis Li

Six aromatic compounds were isolated from the endophytic fungus Colletotrichum sp. of Cephalotaxus hainanensis Li [Cephalotaxus mannii Hook. f.]. Their structures were determined on the basis of chemical and spectroscopic methods. The compound 2 was the enantiomer of compound 1. The compound 4 was the epimeride of the compound 3. The compounds 1, 2, 4 and 5 were evaluated for cytostatic activity against HL-60 and PC-3 cells.     

Anti-inflammatory and analgesic potential of a novel steroidal derivative from Bryophyllum pinnatum

A new steroidal derivative, urs Stigmast-4, 20 (21), 23-trien-3-one and other four compounds were isolated from the leaves of Bryophyllum pinnatum. The structure of this new steroid was elucidated and established by standard spectroscopic methods. Carrageenan induced paw edema model was used for anti-inflammatory and acetic acid induced model used for analgesic activity. This new steroidal compound was found to be active in reducing inflammation (% inhibition 87.29 and 84.45 respectively) when compared with diclofenac. Further, it showed 75.72% protection in analgesic activity in acetic acid induced writhing test in mice. In conclusion the % inhibition against carrageenan induced rat paw edema and % protection against acetic acid induced writhings showed by new compound revealed that the anti-inflammatory and analgesic activity of aqueous extract B. pinnatum are mainly due to the presence of this steroidal compound.     

Antibacterial activity of hydroxyalkenyl salicylic acids from sarcotesta of Ginkgo biloba against vancomycin-resistant Enterococcus

A chloroform fraction prepared from the sarcotesta of Ginkgo biloba showed potent inhibitory activity against vancomycin-resistant Enterococcus (VRE). The active compounds were elucidated to be 2-hydroxy-6-(8-pentadecenyl) salicylic acid (1) and 2-hydroxy-6-(10-heptadecenyl) salicylic acid (2) based on their spectral analysis. Compounds 1 and 2 showed significant antibacterial activities against VRE.     

One new sesquiterpene from Saussurea laniceps

One new guaiane-type sesquiterpene (1) was isolated from Saussurea laniceps. The structure of the new compound was elucidated by spectroscopic data analysis. The immunomodulatory activity of compound 1 was evaluated. It was found that compound 1 showed significant inhibition for proliferation of murine T cells in vitro.