Novel NGF-potentiating limonoids from the fruits of Melia toosendan

Four new limonoids (1–4), together with five known limonoids (5–9), were isolated from the fruits of Melia toosendan. Their structures were elucidated based on extensive spectroscopic analyses (1D- and 2D-NMR, HRESIMS, IR, [α]_D). The isolated compounds were evaluated for their neurite outgrowth-promoting activities. Compounds 2 and 6 significantly enhanced NGF-mediated neurite outgrowth in PC12 cells at concentrations ranging from 0.1 to 50.0 μM.     

不同种源非洲桃花心木对寒害的生理响应

2012年1月,广东省经历了2次低温天气.本研究分别于2次降温后（3 ～10℃）和正常温度下（＞10℃）采集广州和肇庆2片试验林的非洲桃花心木叶片,测定相对电导率（REC）、丙二醛（MDA）含量、脯氨酸（Pro）含量、超氧化物歧化酶（SOD）活性和过氧化物酶（POD）活性5个指标,分析了27个种源对寒害的生理响应模式.结果表明,2次降温均显著提高了非洲桃花心木的REC、Pro含量、SOD和POD活性.相比首次降温,第2次降温后,Pro含量、SOD和POD活性进一步提高,而REC则有所降低,表明植株在2次降温后进一步启动了自身的保护系统.该研究应用耐寒隶属函数值对27个种源进行综合评价,初步选出来自马里（种源10#,20#,22#）和布基纳法索（种源30#,31#,32#）的6个耐寒表现优异的种源.     

非洲桃花心木苗叶斑病研究初报

非洲桃花心木苗叶斑病研究初报李云，骆土寿关键词非洲桃花心木苗，叶斑病，咖啡生小核菌，药剂防治非洲桃花心木（ＫｈａｙａｓｅｎｅｇａｌｅｎｓｉｓＡ．Ｊｕｓｓ．）是著名的热带速生珍贵用材树种和优良的行道及庭园绿化树种。非洲桃花心木苗病害过去有过调查报道，但...     

麻楝、塞楝、杧果、扁桃

<正>麻楝楝科Chukrasia tabularia A.Juss.常绿或半落叶乔木,高10～30m。树干通直,树皮褐色,纵裂,略粗糙,具棕色皮孔,内皮层棕红色。嫩枝及芽被锈色短绒毛。     

非洲桃花心木种源试验及优良个体选择研究

2006年春,在广东省广州市北部山地营建了1块非洲桃花心木种源试验林,包括5个布基纳法索种源,1个中国海南种源。通过5个年度的观测,评价参试种源在广州山地的生长表现和耐寒能力。试验结果如下:①非洲桃花心木是造林容易成活的树种,造林成活率为97.35%,第二年的保存率为95.59%;②非洲桃花心木耐寒能力较差,冬季霜冻会导致部分树木的叶片甚至枝条冻伤,但冻害致死的比例仅为1.84%;③在耐寒能力方面,海南种源的耐寒能力最低,来自布基纳法索的5个种源中,高纬度的北部种源其耐寒能力强于低纬度的南部种源;在生长方面,生长量最大的为海南种源,其6a生平均树高、胸径生长量分别为329.57 cm和3.80 cm,其次为布基纳法索的南部种源,北部种源生长较慢;④根据生长量、耐寒能力及干形等指标,评选出优良个体27株,其平均树高441.58 cm,平均胸径5.95 cm,树高、胸径的平均遗传增益分别为8.54%和0。     

不同种源非洲桃花心木苗期抗寒能力和生长节律研究

2008年1月上旬至2009年7月下旬,对非洲引进的3个桃花心木种源的幼树进行每周1次的观测.结果显示:种源间抗寒能力、树高生长和地径生长以及速生期都存在明显差异.种源3-1324与4-1325在苗期表现出一定的抗寒性,种源1-1320苗期对低温敏感.总体上,非洲桃花心木幼树1年抽梢4～7次,1～2月为树高生长休眠期,...     

Inter- and intra-provenances variations in seed size and seedling characteristics of Khaya senegalensis A. Juss in Burkina Faso

Within- and between-provenance variations in seed and seedling traits of Khaya senegalensis A. Juss were studied at INERA in Burkina Faso. Nursery grown seedlings from four provenances in Burkina Faso were used for the study. The studies revealed significant variability in all traits evaluated. Seed length and weight significantly varied among provenances and families within provenances, where Bopiel and Koyenga had the highest mean values. Height and root collar diameter of 1 year old seedlings significantly varied among families within provenances. Except leaf biomass ratio and carbon isotope ratio which varied significantly among provenances but not among families within provenances, all other seedling biomass traits—total plant biomass, stem biomass ratio, leaf biomass ratio, root biomass ratio, root shoot ratio, specific leaf area, and leaf area ratio were significantly affected by provenances and families within provenances. The magnitude of variation due to family effect ranged from 65 to 93 % for seed size traits, and from 4.5 to 17.8 % for seedling characters. Estimates of family heritability were moderate to high (0.67–0.95) for seed traits, but low to moderate (0.19–0.59) for seedling characters, indicating that much of the total variation in seed traits is due to the genetic effect. The two most prominent provenances, Koyenga and Bopiel, with higher seed size and greater seedling growth could be considered for an eventual K. senegalensis improvement program in Burkina Faso.     

Diterpenoid and limonoids from the stem of Pterorhachis zenkeri

One new diterpenoid, methyl 3alpha-hydroxy-7-oxo-dehydroabietate (1), two new limonoids, 3alpha-deacetyl-amoorastatin (2) and 9beta-amoorastatin (3), and the known limonoid amoorastatin (4) were isolated from the stem of Pterorhachis zenkeri.     

Characterization of host–fungus interactions among wood decay fungi associated with Khaya senegalensis (Desr.) A. Juss (Meliaceae) in Singapore

Tree pruning creates wounds that are amenable for wood decay fungi colonization. To characterize the dynamic host–fungus interactions at this location in Senegal mahogany (Khaya senegalensis), in vitro and in vivo pathogenicity tests were conducted with wood decay fungi associated with this tropical tree species. Fomitiporella caryophylii, Hymenochaete murina and Phellinus noxius isolates were included in this experiment following their frequent isolation from Senegal mahogany pruning wounds. The evaluated isolates demonstrated unique host interactions in laboratory tests that suggest equally divergent prognoses for living Senegal mahoganies affected by these fungi. Although all evaluated fungal isolates successfully breached naturally induced reaction zones, P. noxius alone caused significant mass loss to incubated wood blocks. In addition, P. noxius caused extensive wood decay after inoculation in living hosts, successfully illustrating Koch's postulates for this host–fungus relationship. The wood decay ability, invasiveness and facultative parasitism demonstrated by P. noxius suggest its dominant role in wood decay columns below pruning wounds on living Senegal mahoganies. These results highlight the importance of characterizing specific host–fungus interactions and their implications for wood decay severity below pruning wounds in living trees.     

Coumarinoids from the fruits of Micromelum falcatum

Four new compounds, microminutin B (1), microminutin C (2), micromarinate (3), and secomicromelin (4) as well as 17 known compounds were isolated from the fruits of Micromelum falcatum. All compounds were evaluated for antifungal activity against Pythium insidiosum using disc diffusion assay. P. insidiosum is a fungus-like microorganism for which antifungal agents now available are not effective. The results show that four compounds including secomicromelin (4), 7-methoxy-8-(4′-methyl-3′-furanyl)coumarin (10), micromarin B (17), and isomicromelin (19) could inhibit the mycelia growth of P. insidiosum.     

山核桃外果皮中的抑菌活性成分

用不同溶剂对山核桃外果皮甲醇浸膏进行萃取分离,得石油醚相、氯仿相、乙酸乙酯相、正丁醇相,以番茄早疫病菌、苹果腐烂病菌、小麦赤霉病菌、水稻纹枯病菌、黄瓜菌核病菌等5种病菌进行抑菌活性试验.结果表明:正丁醇相抑菌活性最强,氯仿相和石油醚相次之,乙酸乙酯相最弱.对氯仿相进行初步分离,得到7个单体化合物:乔松酮,黄卡瓦胡椒素,5-羟基-4',7-二甲氧基黄酮,5-羟基-2-甲氧基-1,4-萘醌,5-羟基-6,7-二甲氧基黄烷酮,乔松素,β-谷甾醇,均为首次从山核桃中分离得到,它们对玉米大斑病菌和水稻稻瘟病菌孢子萌发均有不同程度的抑制作用.     

Absolute configurations of new limonoids from a Krishna mangrove,Xylocarpus granatum

Four new limonoids, named granatumins V–Y (1–4), belonging to the small group of limonoids with a C₁–C₂₉ oxygen bridge and a ∆^8,30 double bond, were isolated from the seeds of an Indian mangrove, Xylocarpus granatum, collected in the swamp of Krishna estuary, Andhra Pradesh. The constitutions and absolute configurations of these compounds were established by extensive NMR investigations, single-crystal X-ray crystallography using Cu Kα radiation, and by the comparison of circular dichroism spectrum.     

非洲桃花心木在德宏地区的引种栽培试验

在德宏州林业科学研究所对引自海南的非洲桃花心木进行种子萌发和播种育苗造林试验。结果表明,非洲桃花心木的种子不耐贮藏,需即采即播,发芽率为68%,播种覆土厚度以1~2 cm为宜,适宜德宏热区海拔1 000 m以下山地采用袋苗造林,造林密度一般为3 m×3 m,造林成活率≥90%,造林3年后的保存率为89%。非洲桃花心木栽培4~5年即可郁闭成林,生长旺季为5~10月,12月至翌年4月林木生长缓慢,以半落叶的生理方式渡过冬旱季节。与种源地天然林中的非洲桃花心木相比较,两地5 a生、10 a生及25 a生树高、胸径基本接近,能正常开花结实,表明非洲桃花心木适宜德宏热区造林。     

Bioactive phenolics from the fruits of Livistona chinensis

This study investigated the antioxidant and cytotoxic activity of the phenolics isolated from the fruits of Livistona chinensis. Four new compounds, 1-{ω-isoferul[6- (4-hydroxybutyl)pentadecanoic acid]}-glycerol (1), E-[6′-(5″-hydroxypentyl)tricosyl]-4-hydroxy-3-methoxycinnamate (2), 2-(3′-hydroxy-5′-methoxyphenyl)-3-hydroxylmethyl-7-methoxy-2,3-dihydrobenzofuran-5- carboxylic acid (3), 7-hydroxy-5,4′-dimethoxy-2-arylbenzofuran (4), together with eleven known phenolics (5-15), were isolated and identified. Among these compounds, 1-4, 5-O-caffeoylshikimic acid (5), caffeic acid (7), and 3-O-caffeoylshikimic acid (8) showed potent antioxidant activity. 1-5, and 8 showed potent antiproliferative activities with IC₅₀ values among 5-150 μM against HepG2 human liver cancer, HL-60 human myeloid leukemia, K562 human myeloid leukemia, and CNE-1 human nasopharyngeal carcinoma cell lines. On the basis of these findings, it could be proposed that the fruits of L. chinensis may serve as attractive mines of powerful anticancer and antioxidant agents for various purposes.     

Cytotoxic sesquiterpenoids from the fruits of Lindera communis

A new sesquiterpenoid, namely Linerenone (1), together with three known sesquiterpenoids (2–4), were isolated from the fruits of Lindera communis. Their structures were determined by extensive spectroscopic analysis including 1D, 2D-NMR and HR-MS spectra. Compound 1 showed significant cytotoxic activity against H460, ES2 and DU145 cancer cells with IC₅₀ of 2.1 μg/mL, 2.8 μg/mL and 3.0 μg/mL, respectively.     

Phytoconstituents from Vitex agnus-castus fruits

A new labdane-diterpene, viteagnusin I (1), together with 23 known phytoconstituents were isolated from the fruits of Vitex agnus-castus L, and their structures characterized by spectroscopic methods (NMR and MS). The known compounds include ten flavonoids, five terpenoids, three neolignans, and four phenolic compounds, as well as one glyceride. Biological evaluation identified apigenin, 3-methylkaempferol, luteolin, and casticin as weak ligands of delta and mu opioid receptors, exhibiting dose-dependent receptor binding.     

Amides from Piper tuberculatum fruits

The fruits of Piper tuberculatum Jacq yielded piperine S (1) and N-(12,13,14-trimethoxydihydrocinnamoyl)-delta(3)-piperidin-2-one (2). Their complete NMR analysis based on one- and two-dimensional experiments is reported.     

Constituents from Piper marginatum fruits

The hexane extract of the dried fruits of Piper marginatum yielded 1-(1Z-propenyl)-2,4,6-trimethoxybenzene, a new natural product, besides 3-farnesyl-4-hydroxybenzoic acid and caryophyllene oxide.     

Antifungal constituent from Gordonia dassanayakei.

The hexane extract of the stem bark of Gordonia dassanayakei showed high antifungal activity against plant pathogenic fungi Curvularia sp., Colletotrichum gloeosporioides, Rhizoctonia solani, Corynespora cassiicola, and Fusarium sp. A compound responsible for the antifungal activity was isolated and identified as 3-formyl-2,4-dihydroxy-6-methylbenzoic acid 3-hydroxy-4-(methoxycarbonyl)-2,5-dimethylphenyl ester (1).