亚麻叶白千层化学成分研究

目的研究亚麻叶白千层Melaleucalinariifolia枝、叶中的化学成分。方法采用硅胶、SephadexLH-20、ODS、以及Pre-HPLC等现代分离方法进行系统地分离纯化,并根据化合物的理化性质和波谱数据进行结构鉴定。采用CCK8法初步评价化合物1～6对6种肿瘤细胞(人肺腺癌NCI-H441细胞、人大细胞肺癌NCI-H460细胞、人肺癌A549细胞、人卵巢腺癌SKOV3细胞、人宫颈癌HeLa细胞和人肾透明细胞癌caki-1细胞)的体外细胞增殖抑制活性。结果从亚麻叶白千层醋酸乙酯部位分离得到15个化合物,分别鉴定为3-O-乙酰熊果酸(1)、3β-acetoxy-11-ursen-13α,30-olide(2)、betulinal(3)、diospyrolide(4)、3β-O-(E)-cumaroyl-alphitolinsaeure(5)、3',4'-二羟基肉桂酸白桦脂酸酯(6)、熊果醇(7)、白桦脂醇(8)、豆甾-4-烯-3-酮(9)、5,7,4'-三羟基黄酮3-O-α-L-毗喃鼠李糖苷(10)、山柰酚-3-O-(6′′-没食子酰基)-β-D-葡萄糖苷(11)、α-生育酚(12)、methoxytocopherol(13)、α-tocopherolquinone(14)、植醇(15)。CCK8测试结果显示,化合物1、3、5、6对人类肿瘤细胞显示出中等强度的增殖抑制作用。结论所有化合物均为首次从该植物中分离得到,其中化合物2、4、5、9～11、13、14为首次从该属植物中分离得到。化合物1、3、5、6对人类肿瘤细胞表现出一定的细胞毒活性,半数抑制浓度(IC50)值在3.85～25.63μmol/L。     

Leucoxenols A and B,two new phenolics from Bornean medicinal plant Syzygium leucoxylon

The medicinal plant, Syzygium leucoxylon or commonly known as Obah found in North Borneo was considered as traditional medicine by local committee. Two new phenolics, leucoxenols A (1) and B (2) were isolated and identified as major secondary metabolites from the leaves of S. leucoxylon. Their chemical structures were elucidated based on spectroscopic data such as NMR and HRESIMS. Furthermore, these compounds were active against selected strains of fungi.     

番石榴叶化学成分研究

目的:研究番石榴Psidium guajava叶的化学成分.方法:利用葡聚糖凝胶Sephadex LH-20、硅胶和MPLC等色谱方法进行化合物的分离纯化,根据化合物的理化性质、波谱数据进行结构鉴定.结果:从番石榴叶中分离得到9个单体化合物,分别为:乌苏酸(ursolic acid,1),2α-羟基乌苏酸(2α-hydroxyursolic acid,2),2α-羟基齐墩果酸(2α-hydroxyoleanolic acid,3),番石榴苷(morin-3-O-α-L-arabopyranoside,4),槲皮素(quercetin,5),金丝桃苷(hyperin,6),杨梅素-3-O-β-D-葡萄糖(myricetin-3-O-β-D-glucopyranosid,7),quercetin-3-O-β-D-glucuronopyranoside(8),1-O-没食子酰基-β-D-葡萄糖(1-O-galloyl-β-D-glucose,9).结论:化合物3,7～9为首次从该植物中分离得到.     

New anthracene glycosides from <Emphasis Type="Italic">Rhodomyrtus tomentosa</Emphasis> stimulate osteoblastic differentiation of MC3T3-E1 cells

Two new anthracene glycosides (1, 2) were isolated from aerial parts of Rhodomyrtus tomentosa, along with three known compounds (3–5). The structures of two new compounds were established to be 4,8,9,10-tetrahydroxy-2,3,7-trimethoxyanthracene-6-O-β-D-glucopyranoside (1) and 2,4,7,8,9,10-hexahydroxy-3-methoxyanthracene-6-O-α-L-rhamnopyranoside (2) based on spectroscopic and chemical methods. Among them, compound 1, 2, and 5 significantly (P<0.05) increased the alkaline phosphatase activity, collagen synthesis, and mineralization of the nodules of MC3T3-E1 osteoblastic cells compared to those of the control, respectively.     

互叶白千层的化学成分研究

目的 研究互叶白千层Melaleuca alternefolia的化学成分.方法 采用硅胶柱色谱和重结晶方法进行分离纯化,根据理化性质和波谱数据鉴定其结构.结果 分离得到了12个化合物,鉴定了11个化合物,分别为:n-tricontyl-4-cinnamate (1)、槲皮素(2)、山柰酚(3)、白桦脂酸(4)、没食子酸(5)、没食子酸乙酯(6)、β-谷甾醇(7)、原儿茶酸(8)、胆甾醇(9)、三十二醇(10)、吉达酸(11).结论 除化合物5、7外,其他9个化合物为首次从该属植物中分离得到;除化合物4外,其他10个化合物为首次从该植物中分离得到.     

Antidermatophytic triterpenoids from Syzygium jambos (L.) Alston (Myrtaceae)

Chemical investigation of the EtOAc extract of the stem bark of Syzygium jambos (L.) Alston (Myrtaceae) afforded a number of known triterpenes such as friedelin, beta-amyrin acetate, betulinic acid and lupeol. Friedelin was submitted to a Baeyer-Villiger oxidation, and was also reduced with LiAlH(4) to give the known friedelolactone and friedelanol, respectively. These compounds were identified by comparison of NMR spectral data with those from the literature. The EtOAc extract and the isolated compounds were tested for their antidermatophytic activity against three dermatophyte species: Microsporum audouinii, Trichophyton mentagrophytes and Trichophyton soudanense, commonly found in Cameroon. Betulinic acid and friedelolactone were the most active compounds, and the most sensitive fungi were Trichophyton soudanense and Trichophyton mentagrophytes.     

Evaluation of phytochemicals from medicinal plants of Myrtaceae family on virulence factor production by Pseudomonas aeruginosa

Virulence factors regulated by quorum sensing (QS) play a critical role in the pathogenesis of an opportunistic human pathogen, Pseudomonas aeruginosa in causing infections to the host. Hence, in the present work, the anti‐virulence potential of the medicinal plant extracts and their derived phytochemicals from Myrtaceae family was evaluated against P. aeruginosa. In the preliminary screening of the tested medicinal plant extracts, Syzygium jambos and Syzygium antisepticum demonstrated a maximum inhibition in QS‐dependent violacein pigment production by Chromobacterium violaceum DMST 21761. These extracts demonstrated an inhibitory activity over a virulence factor, pyoverdin, production by P. aeruginosa ATCC 27853. Gas chromatography–mass spectrometric (GC‐MS) analysis revealed the presence of 23 and 12 phytochemicals from the extracts of S. jambos and S. antisepticum respectively. Three top‐ranking phytochemicals, including phytol, ethyl linoleate and methyl linolenate, selected on the basis of docking score in molecular docking studies lowered virulence factors such as pyoverdin production, protease and haemolytic activities of P. aeruginosa to a significant level. In addition, the phytochemicals reduced rhamnolipid production by the organism. The work demonstrated an importance of plant‐derived compounds as anti‐virulence drugs to conquer P. aeruginosa virulence towards the host.     

Antimicrobial and antileukemic effects: in vitro activity of Calyptranthes grandifolia aqueous leaf extract

ABSTRACT

Natural products are still a promising source of bioactive molecules. Food and Drug Administration data showed that approximately 49% of the approved molecules originate naturally or chemically-resemble these substances, of which more than 70% are being used in anticancer therapy. It is noteworthy that at present there are no scientific studies to prove the effectiveness and safety of a number of plants used in folk medicine such as in the case of Calyptranthes grandifolia O. Berg (Myrtaceae) originally from South America. The aim of the present study was to determine the biological potential and toxicological effects of the aqueous leaf extract of C. grandifolia. The main detected phytoconstituents were condensed tannins and flavonoids and a high quantity of polyphenols. Regarding the antimicrobial potential, the extract exerted inhibitory activity against Pseudomonas aeruginosa. The results also revealed the extract induced DNA damage in a concentration-dependent manner in RAW 264.7 cells. In addition, C. grandifolia produced cytotoxicity in leukemia cell lines (HL60 and Kasumi-1) without affecting isolated human lymphocytes but significantly inhibited JAK3 and p38α enzyme activity. Taken together, these findings add important information on the biological and toxicological effects of C. grandifolia, indicating that aqueous extract may be a source of natural antimicrobial and antileukemic constituents.     

Acylphloroglucinol derivatives from Decaspermum gracilentum and their antiradical and cytotoxic activities

Two new acylphloroglucinol derivatives, 1-(hexanoyl)phloroglucinol-α-d-arabinopyranoside (1) and 1-(hexanoyl)phloroglucinol-β-d-glucopyranoside (2), along with two known ones, 1-(acetyl)phloroglucinol-β-d-glucopyranoside (3) and ethyl 2,4,6-trihydroxybenzoate (4), were isolated from the EtOAc soluble fraction of EtOH extract of Decaspermum gracilentum. The structures of the new compounds were determined by extensive spectroscopic analyses including HRESIMS, 1D and 2D NMR data. Interestingly, all of the compounds showed ABTS^·+ radical scavenging activity with the IC₅₀ values less than 10 μM. Furthermore, compounds 3 and 4 displayed moderate cytotoxicity on human non-small-cell lung carcinoma cell line A549 (IC₅₀ = 50.9 μΜ) and human renal carcinoma cell line 786-O (IC₅₀ = 38.6 μΜ), respectively.     

Sex-specific effects of Eugenia punicifolia extract on gastric ulcer healing in rats

AIM To evaluate the sex-specific effects of a hydroalcoholic extract from Eugenia punicifolia(HEEP) leaves on gastric ulcer healing.METHODS In this rat study involving males, intact(cycling) females, and ovariectomized females, gastric ulcers were induced using acetic acid. A vehicle, lansoprazole, or HEEP was administered for 14 d after ulcer induction. Body weight was monitored throughout the treatment period. At the end of treatment, the rats were euthanized and the following in vivo and in vitro investigations were performed: macroscopic examination of the lesion area and organ weights, biochemical analysis, zymography, and evaluation of protein expression levels. Additionally, the concentration-dependent effect of HEEP was evaluated in terms of subacute toxicity and cytotoxicity.RESULTS Compared to the vehicle, HEEP demonstrated a great healing capacity by substantially reducing the ulcerative lesion area in males(52.44%), intact females(85.22%), and ovariectomized females(65.47%), confirming that HEEP accelerates the healing of acetic acidinduced gastric lesions and suggesting that this effect is modulated by female sex hormones. The antiulcer effect of HEEP was mediated by prostaglandin E2 only in male rats. Overall, the beneficial effect of HEEP was the highest in intact females. Notably, HEEP promoted the expression of vascular endothelial growth factor(intact vs ovariectomized females) and decreased the expression of Caspase-8 and Bcl-2(intact female vs male or ovariectomized female). Additionally, HEEP enhanced fibroblast proliferation and migration into a wounded area in vitro, confirming its healing effect. Finally, no sign of subacute toxicity or cytotoxicity of HEEP was observed.CONCLUSION In gastric ulcers, HEEP-induced healing(modulated by female sex hormones; in males, mediated by prostaglandin) involves extracellular matrix remodeling, with gastric mucosa cell proliferation and migration.