Antitrichomonas in vitro activity of Cussonia holstii Engl

Cussonia holstii is a traditional medicinal plant used in Kenya, which has not been studied chemically up-to-date. Upon biological screening, a substantial antitrichomonas activity was found in the dichloromethane extract of the bark of Cussonia holstii. A detailed chromatographic study using centrifugal partition chromatography revealed that a pentacyclic triterpenoid, i.e., hederagenin, is the antitrichomonas constituent of the plant with a IC50 of 2.8 microM.     

Wound Healing Potential of an Oleoresin Essential Oil Chemotype from Canarium schweinfurthii Engl.

This study was conducted to investigate the chemical composition of essential oil (EO) extracted from an oleoresin of Canarium schweinfurthii widespread in the Gabonese tropical forest. A great variability in the chemical composition of EO was observed, among which a chemical profile rich in terpinolene and α-phellandrene (31.2 and 21.8%, respectively), was found and tested as a natural active ingredient for topical applications. After the evaluation of eye and skin irritancy and sensitization potentials of EO on in vitro and in chemico models, the in vitro modulating potential on a model of wound re-epithelialization was assessed. The terpinolene and α-phellandrene-rich chemotype have been proven to accelerate wound healing in a dose-dependent manner (concentration range from 1.8 to 9.0 μg/mL). In addition, the ability of this EO to modulate the pro-inflammatory response in human keratinocytes stimulated by UVB was observed in vitro by the reduction in levels of interleukin 6 (IL-6) and tumour necrosis factor-alpha (TNF-α), suggesting a possible implication during the inflammation phase of wound healing. Despite the high variability in EO composition, a method of solid-phase microextraction (SPME) of the oleoresin headspace is proposed for the in situ identification of the terpinolene and α-phellandrene-rich chemotype instead of conducting hydrodistillation. These results offer interesting perspectives for the development of innovative natural ingredients for the topical route, ingredients obtained in an eco-responsible and non-destructive way.     

Preussianone, a new flavanone-chromone biflavonoid from Garcinia preussii Engl

A new flavanone-chromone biflavonoid, preussianone (1), has been isolated from the leaves of Garcinia preussii, along with four known biflavonoids. The absolute stereostructures were elucidated by chemical, spectroscopic, and chiroptical methods. The biological properties of the new biflavonoid against several bacterial strains were evaluated.     

Synthesis of a New Cerebroside Isolated from Typhonium giganteum Engl

The stereoselecfive synthesis of typhoniside, a new cerebroside isolated from Typhonium giganteum Engl. was accomplished.Cerebrosides are a kind of glycolipids highly enriched on the surface of myelin-producing cells and are composed by C18-4,8-sphingadienine, a-hydroxy acid and a saccharide head. It was the first time that cerebrosides were isolated from this traditional Chinese medicine (TCM) by us. In this paper, C18-4,8-sphingadienine was synthesized from D-xylose via a SN2 type reaction, α-Hydroxy acid was prepared from (R)-4-hydroxyte-trahydrofuran-2-one, which in turn could be obtained from Lascorbic acid.     

Long-chain alkanoic acid esters of lupeol from Dorstenia harmsiana Engl. (Moraceae)

In addition to lupeol (1a), three long-chain alkanoic acid esters of lupeol, in which two were new, were isolated from the hexane and ethyl acetate twigs extract of Dorstenia harmsiana Engl. (Moraceae). The structures of the new compounds were elucidated on the basis of 1D and 2D NMR experiments. Some isolated compounds were evaluated for their antimicrobial activities. The lupeol and its three long-chain alkanoic acid esters showed antifungal and antibacterial activities.     

Soyauxinine,a New Indolopyridoquinazoline Alkaloid from the Stem Bark of Araliopsis soyauxii Engl. (Rutaceae)

The chemical investigation of the total alkaloid extract (TAE) of the stem bark of Araliopsis soyauxii (Rutaceae) afforded an unreported indolopyridoquinazoline (compound 1) along with nine previously known alkaloids 2–10. In addition, six semi-synthetic derivatives 3a–c, 4b, 5a and 6a were prepared by allylation and acetonidation of soyauxinium nitrate (5), edulinine (3), ribalinine (4) and arborinine (6). The structures and spectroscopic data of five of them are reported herein for the first time. The suggested mechanism for the formation of the new N-allylindolopyridoquinazoline 5a is presented. The structures of natural and derived compounds were determined employing extensive NMR and MS techniques. The absolute configuration of stereogenic centers in compounds 2–4 were determined using NOESY technique and confirmed by the single-crystal X-ray diffraction (SC-XRD) technique. The use of SC-XRD further enabled us to carry out a structural revision of soyauxinium chloride recently isolated from the same plant to soyauxinium nitrate (5). The TAE, fractions, compounds 1–7 and 9, and semi-synthetic derivatives 3a–c, 4b, 5a and 6a were evaluated for their cytotoxic activity towards the cervix carcinoma cell line KB-3-1. No significant activity was recorded for most of the compounds except for 9, which showed moderate activity against the tested cancer cell lines.     

A novel antimicrobial flavonoid from the stem bark of Commiphora pedunculata (Kotschy & Peyr.) Engl.

A new flavonoid, 2-(3,5-dihydroxy-4-methoxy-phenyl)-3,5-dihydroxy-8,8-dimethyl-2,3-dihydro-8H-pyrano[3,2]chromen-4-one, together with previously reported epicatechin was isolated from the ethyl acetate soluble fraction of the methanol extract of the stem bark of Commiphora pedunculata. The structures of these compounds were elucidated based on extensive analysis of their spectral data, including 1 and 2D NMR. The compounds were active against 9 out of 12 tested microorganisms including a resistant strain; vancomycin-resistant entrococci (VRE), Escherichia coli, Staphylococcus aureus and Candida albicans. The zones of inhibition ranged between 22 and 34 mm against the microorganisms. The minimum inhibitory concentration was as low as 6.25 μg/mL against Shigella dysentriae, Bacillus cereus and S. aureus while the minimum bactericidal concentration was as low as 50 μg/mL against Pseudomonas aeruginosa, VRE and C. albicans. This is the first report of the isolation of the compound.     

Gas Chromatography-Mass Spectroscopic,high performance liquid chromatographic and In-silico characterization of antimicrobial and antioxidant constituents of Rhus longipes (Engl)

Rhus longipes is one of those underutilized plant species with inherent values. Therefore, we conducted a phytochemical study and investigated the antioxidant and antimicrobial potentials of the plant extracts. Aqueous and ethanol extract was subjected to phytochemical analysis. Gas chromatography-mass spectroscopy was performed to identify the volatile compounds while high performance liquid chromatography was done to identify the phenolic and flavonoids in the ethanol extract. Bioactivity and molecular docking analysis was also done for the identification of the bioactive constituents. Tannins, flavonoids, phenolics, terpenoids, steroids, alkaloids, and saponins were identified both in the ethanol and in aqueous extracts of R. longipes. The extracts and ascorbic acid exhibited radical inhibition in a concentration dependent manner. The IC₅₀ values; 3.23, 4.13, 70.75 µg/mL (ABTS), 200.82, 103.63, 390.83 µg/mL (DPPH), 10.06, 93.46, 253.26 µg/mL (O₂), and 99.77, 109.23, 446.34 µg/mL (NO) for ascorbic acid, ethanol and aqueous extract respectively showed that ethanol extract exhibited better radical inhibition than the aqueous extract. 4-hydroxybenzoic and 4-hydroxycoumarin were the most abundant phenolics in the extract. The ethanol extract of R. longipes demonstrated broad-spectrum antibacterial activity with inhibition zone of 25.5 mm against S. aureus, 27.5 mm against E. coli, and 20.5 mm against P. aeruginosa. The identified phytochemicals demonstrated inhibitory potentials against bacterial glucosamine 6-phosphate synthase, penicillin-binding protein 3, DNA gyrase and β-lactamase. It is evident that R. longipes have some antioxidant and antibacterial properties and the plant contain important phytochemicals with ability to retard food oxidation and deterioration and thus could be annexed for various industrial and medicinal purposes.     

New Natural Oxygenated Sesquiterpenes and Chemical Composition of Leaf Essential Oil from Ivoirian Isolona dewevrei (De Wild. & T. Durand) Engl. & Diels

This study aimed to investigate the chemical composition of the leaf essential oil from Ivoirian Isolona dewevrei. A combination of chromatographic and spectroscopic techniques (GC(RI), GC-MS and ¹³C-NMR) was used to analyze two oil samples (S1 and S2). Detailed analysis by repetitive column chromatography (CC) of essential oil sample S2 was performed, leading to the isolation of four compounds. Their structures were elucidated by QTOF-MS, 1D and 2D-NMR as (10βH)-1β,8β-oxido-cadin-4-ene (38), 4-methylene-(7αH)-germacra-1(10),5-dien-8β-ol (cis-germacrene D-8-ol) (52), 4-methylene-(7αH)-germacra-1(10),5-dien-8α-ol (trans-germacrene D-8-ol) (53) and cadina-1(10),4-dien-8β-ol (56). Compounds 38, 52 and 53 are new, whereas NMR data of 56 are reported for the first time. Lastly, 57 constituents accounting for 95.5% (S1) and 97.1% (S2) of the whole compositions were identified. Samples S1 and S2 were dominated by germacrene D (23.6 and 20.5%, respectively), followed by germacrene D-8-one (8.9 and 8.7%), (10βH)-1β,8β-oxido-cadin-4-ene (7.3 and 8.7), 4-methylene-(7αH)-germacra-1(10),5-dien-8β-ol (7.8 and 7.4%) and cadina-1(10),4-dien-8β-ol (7.6 and 7.2%). Leaves from I. dewevrei produced sesquiterpene-rich essential oil with an original chemical composition, involving various compounds reported for the first time among the main components. Integrated analysis by GC(RI), GC-MS and ¹³C-NMR appeared fruitful for the knowledge of such a complex essential oil.     

Alkaloids from stems of Esenbeckia leiocarpa Engl. (Rutaceae) as potential treatment for Alzheimer disease

Esenbeckia leiocarpa Engl. (Rutaceae), popularly known as guarant?, goiabeira, is a native tree from Brazil. Bioactivity-guided fractionation of the ethanol stems extract afforded the isolation of six alkaloids: leiokinine A, leptomerine, kokusaginine, skimmianine, maculine and flindersiamine. All isolated compounds were tested for acetyl cholinesterase inhibition, in vitro and displayed anticholinesterasic activity. The alkaloid leptomerine showed the highest activity (IC?? = 2.5 mM), similar to that of the reference compound galanthamine (IC?? = 1.7 mM). The results showed for the first time the presence of alkaloids leptomerine and skimmianine in E. leiocarpa (Engl.) with potent anticholinesterasic activity.     

Chemical Variability and In Vitro Anti-Inflammatory Activity of Leaf Essential Oil from Ivorian Isolona dewevrei (De Wild. & T. Durand) Engl. & Diels

The chemical variability and the in vitro anti-inflammatory activity of the leaf essential oil from Ivorian Isolona dewevrei were investigated for the first time. Forty-seven oil samples were analyzed using a combination of CC, GC(RI), GC-MS and ¹³C-NMR, thus leading to the identification of 113 constituents (90.8–98.9%). As the main components varied drastically from sample to sample, the 47 oil compositions were submitted to hierarchical cluster and principal components analyses. Three distinct groups, each divided into two subgroups, were evidenced. Subgroup I−A was dominated by (Z)-β-ocimene, β-eudesmol, germacrene D and (E)-β-ocimene, while (10βH)-1β,8β-oxido-cadina-4-ene, santalenone, trans-α-bergamotene and trans-β-bergamotene were the main compounds of Subgroup I−B. The prevalent constituents of Subgroup II−A were germacrene B, (E)-β-caryophyllene, (5αH,10βMe)-6,12-oxido-elema-1,3,6,11(12)-tetraene and γ-elemene. Subgroup II−B displayed germacrene B, germacrene D and (Z)-β-ocimene as the majority compounds. Germacrene D was the most abundant constituent of Group III, followed in Subgroup III−A by (E)-β-caryophyllene, (10βH)-1β,8β-oxido-cadina-4-ene, germacrene D-8-one, and then in Subgroup III−B by (Z)-β-ocimene and (E)-β-ocimene. The observed qualitative and quantitative chemical variability was probably due to combined factors, mostly phenology and season, then harvest site to a lesser extent. The lipoxygenase inhibition by a leaf oil sample was also evaluated. The oil IC₅₀ (0.020 ± 0.005 mg/mL) was slightly higher than the non-competitive lipoxygenase inhibitor NDGA IC₅₀ (0.013 ± 0.003 mg/mL), suggesting a significant in vitro anti-inflammatory potential.     

Response surface optimization of ultrasound‐assisted flavonoids extraction from the flower of Citrus aurantium L. var. amara Engl

Citrus aurantium L. var. amara Engl is a member of genus Citrus (Rutaceae) and has been used in Chinese medicine with the effectiveness of digestant and expectorant. Ultrasonic‐assisted extraction process for maximum flavonoids from the flower of Citrus aurantium L. var. amara Engl was investigated by response surface methodology. Through single factor experiment, ranges of the main variables (including ethanol concentration, solid/liquid ratio, extraction time and temperature) affecting the extraction yield of flavonoids were confirmed. Box–Behnken central composite design consisting of 24 experimental runs and 5 replicates at zero point was then applied and a regress model was obtained to predict the optimal extraction yield. The ANOVA indicated that the regression equation fits very well with the actual situation, reflecting the relationship between the extraction yield of flavonoids and extraction conditions. The optimal conditions were as follows: extraction temperature 72.11°C, time 51.89 min, ethanol concentration 51.19% and liquid/solid ratio of 40:10. Under the optimal conditions, the maximum response value of yield (1.88%) was consistent with the experimental value (1.87%), indicating the feasibility and validation of response surface methodology in optimizing the extraction of flavonoids from the flower of Citrus aurantium L. var. amara Engl.     

Absolute configuration of bioactive furanogermacrenones from Commiphora erythraea (Ehrenb) Engl. by computational analysis of their chiroptical properties

Absolute configurations (+)-(4S), (+)-(3S,4R), (−)-(2S,4S), and (−)-(1R,2R,4S) were assigned, for the first time, to bioactive furanogermacranes extracted from Commiphora erythraea resin by DFT computational analysis of their ORD curves and ECD spectra. This analysis established that all of these compounds share the same absolute configuration at the methyl-substituted carbon thus allowing us to hypothesize a biosynthetic relationship among these structurally related metabolites.     

SFE-CO2 extract from Typhonium giganteum Engl. tubers, induces apoptosis in human hepatoma SMMC-7721 cells involvement of a ROS-mediated mitochondrial pathway

Typhonium giganteum Engl. (BaiFuzi) is one of the herbs commonly used in traditional Chinese medicine against cancer. In our previous studies, 37 compounds were identified the SFE-CO(2) (supercritical fluid extraction with CO(2)) extract by GC-MS, including the four major components [β-sitosterol (40.22%), campesterol (18.45%), n-hexadecanoic acid (9.52%) and (Z,Z)-9,12-octadecadienoic acid (8.15%)]. The anti-cancer mechanisms of the SFE-CO(2 )extract from T. giganteum Engl. tubers have not been reported as yet. In this paper, the molecular mechanisms of the SFE-CO(2) extract-mediated apoptosis in SMMC-7721 cells were further examined. SFE-CO(2) extract inhibited the growth of SMMC-7721 cells in a time- and dose-dependent manner, arrested the cell cycle in the S phase and G2/M phase, and induced apoptosis. In addition, reactive oxygen species (ROS) increase, reduction of mitochondrial membrane potential, a rise in intracellular calcium levels were found in SMMC-7721 cells after treated with the extract. Western blot analysis showed that the extract caused down-regulation of Bcl-2 expression, and up-regulation of Bax expression. Moreover, caspase-3 and caspase-9 protease activity significantly increased in a dose-dependent manner. Collectively, our results showed that the SFE-CO(2) extract from T. giganteum Engl. tubers induces apoptosis in SMMC-7721 cells involving a ROS-mediated mitochondrial signalling pathway.     

Fingerprint chemotaxonomic GC–TOFMS profile of wood and bark of mangrove tree Sonneratia caseolaris (L.) Engl.

The bark and wood of Sonneratia caseolaris (L.) Engl. have been analyzed for chemical profile by GC–TOFMS. Overall thirty-two compounds from bark and twenty-eight compounds from wood have been detected. Sixteen constituents have been found to be common in both the extracts. GC–TOFMS chemical profile may be a significant finger print chemotaxonomic marker as an identity of this plant.     

气相色谱法研究聚辛烯-1与不同溶剂的热力学相互作用

用气相色谱法测定了聚辛烯－１与８种溶剂的Ｆｌｏｒｙ－Ｈｕｇｇｉｎｓ相互作用参数χ１和聚辛烯－１的溶解度参数,确定了χ１与温度的数学关系式。测定结果表明聚辛烯－１溶于正辛烷是一个放热过程。     

姜黄素类似物的合成及其生物活性的测定

实验合成了姜黄素的Knoevenagel缩合物4-(2-呋喃次甲基)姜黄素C1,氨基硫脲Schiff 碱配体E1,及其Schiff 碱配体的Zn(Ⅱ)配合物D1.采用DPPH法测定了产品清除自由基的能力,结果表明产品C1对DPPH自由基清除率为82.0%.在pH7.2的Tris-Hcl缓冲溶液中,采用紫外光谱和荧光光谱研究了C1与鲱鱼精DNA的相互作用,结果表明,C1与DNA是通过嵌插模式发生相互作用的,其键合常数为Kq =9.31×103.     

一个取代的1, 5-苯并二氮杂卓的晶体结构及构象研究

用X射线衍射方法测定了4-苯甲酰基-3-(邻氯苯基)-1-乙酸乙酯基-1a-苯基-1,1a,2,3-四氢化-4H-环丙胺-[1,2-a][1,5]-苯并二氯杂卓化合物的晶体结构,晶体结构测定结果表明分子核心骨架二氮杂卓为类船式构象。用动力学模拟退火(SimulatedAnnealing)方法对分子进行了构象分析,结果表明分子中的二氮杂卓七元环具有三种较稳定的构象,其中以船式构象为最稳定,并存在着明显的芳环堆积作用。分子中七元环同时并接苯环和三元环,且环中的N(2)-C(12)-C(11)-N(1)有π键成分,大大限制了七元环构象的相互转换。     

Modified spectrophotometric method for the determination of selenium in environmental and mineral mixtures using 2,3-diaminonaphthalene

Reaction of selenium with 2,3-diaminonaphthalene was reinvestigated with bromide ion as a catalyst. In acid medium, selenium reacts with the above reagent to form a complex extractable with cyclohexane and with an absorption maximum at 378.5 nm. The molar absorptivity of the complex is 17.5 x 10(3) 1 mol(-1) cm(-1). Beer's law is obeyed in the range 0.5-12 mg 1(-1). The method is reproducible and the standard and relative standard deviation for seven replicate analyses of 2 mg 1(-1) of selenium are 0.05 absorbance units and 2.5%, respectively. The limit of detection is 0.012 mg 1(-1). The method was optimized for the determination of selenium in water, soil, cereal and mineral mixtures and cattle feed and was compared with the reported 2,3-diaminonaphthalene method.     

Synthesis,Photoconductivity and Electro-optical Properties of Disperse Red-1 Bonded PVK

Polyvinylcarbazole was chloromethylated then condensed with Na salt of Disperse Red-1. The produced new polymer.,Disperse Red-1 bonded HVK(PVK-DR1) was characterized. The photoconductivity and electro-optical coefficient were measured using a thin film fabricated from the polymer. The result shows that the film is photoconducting electro-optical active. The photoconductivity is electric field dependent. When the applied voltage was 100 to 200 mV/M, the pholocurrent was 1 to 188 nA, and photoconductivity was 6 to 241×10^-13S·cm^-1, quantum efficient was 0.18% to 5%. Electro-optical efficient was 1.3 pm/V.