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Eight new species of Cestrum (Solanaceae) from Mesoamerica  [cached]
Alex Monro
PhytoKeys , 2012, DOI: 10.3897/phytokeys.8.2238
Abstract: As part of the preparation of a taxonomic revision of Cestrum (Solanaceae) for Flora Mesoamericana eight hitherto undescribed species from Mexico, Guatemala, Costa Rica and Panama were identified. These eight new species are described and illustrated. Affinities of the species are discussed and Global Species Conservation Assessments presented. The new species are Cestrum amistadense A.K. Monro, sp. nov. (Vulnerable) which most closely resembles Cestrum longiflorum Ruiz & Pav., Cestrum contrerasianum A.K. Monro, sp. nov. (Vulnerable) which most closely resembles Cestrum formosum C.V.Morton, Cestrum darienense A.K. Monro, sp. nov. (Near Threatened) which most closely resembles Cestrum morae Hunz., Cestrum gilliae A.K. Monro, sp. nov. (Near Threatened) which most closely resembles Cestrum morae, Cestrum haberii A.K. Monro, sp. nov. (Vulnerable) which most closely resembles Cestrum poasanum Donn.Sm., Cestrum knappiae A.K. Monro, sp. nov. (Near Threatened) which most closely resembles Cestrum acuminatum Francey, Cestrum lentii A.K. Monro, sp. nov. (Near Threatened) which most closely resembles Cestrum johnniegentrianum D’Arcy and Cestrum talamancaense A.K. Monro (Least Concern) which most closely resembles Cestrum laxum Benth.
Phenolic Glucosides from Dendrobium aurantiacum var. denneanum and Their Bioactivities  [PDF]
Liang Xiong,Zhi-Xing Cao,Cheng Peng,Xiao-Hong Li,Xiao-Fang Xie,Ting-Mo Zhang,Qin-Mei Zhou,Lian Yang,Li Guo
Molecules , 2013, DOI: 10.3390/molecules18066153
Abstract: A new 8,4¢-oxyneolignane glucoside 1 has been isolated from the stems of Dendrobium aurantiacum var. denneanum together with six known phenolic glucosides 2- 7. The structure of the new compound, including its absolute configuration, was determined by spectroscopic and chemical methods as (–)-(7 S,8 R,7¢ E)-4-hydroxy-3,3¢,5,5¢-tetramethoxy-8,4¢-oxyneolign-7¢-ene-7,9,9¢-triol 7,9¢-bis- O- β-D-glucopyranoside ( 1). In the in vitro assays, compound 1 and (-)-syringaresinol-4,4¢-bis- O- β-D-glucopyranoside ( 2) showed evident activity against glutamate-induced neurotoxicity in PC12 cells. Shashenoside I ( 4) showed a selective cytotoxic activity with the IC 50 value of 4.17 μM against the acute myeloid leukemia cell line MV4-11, while it was inactive against 10 other human tumor cell lines.
Biologia reprodutiva de Canistrum aurantiacum E. Morren (Bromeliaceae) em remanescente da Floresta Atlantica, Nordeste do Brasil
Siqueira Filho, José Alves de;Machado, Isabel Cristina S.;
Acta Botanica Brasilica , 2001, DOI: 10.1590/S0102-33062001000300011
Abstract: canistrum aurantiacum, a shade-tolerant species, is either an epiphyte or a terrestrial plant, endemic of the coastal atlantic forest understory from pernambuco and alagoas. the species forms dense terrestrial populations, flowering from november to mid-february with the peak of flowering in the last half of january, when 12 flowers per plant may open during one day. the flowers are tubular and vary from 4-5 cm in length within the same inflorescence. the flowers begin to open from the centre of the inflorescence and progress towards the periphery. c. aurantiacum is an ornithophilous species, whose syndrome is characterised by odourless flowers, vivid-red involucral and scape bracts, and golden-yellow corolla. nectar volume varies from 22,6 to 40,5 ml, with concentration of 26-33 %. anthesis begins at dawn, around 5:20 a.m. and the flowers close around 4:00 p.m. pollen and stigma are functional during the whole anthesis. hummingbirds chlorostilbon aureoventris and thalurania watertonii (trochilinae), glaucis hirsuta, phaethornis pretrei and p. ruber (phaethornitinae) visited the flowers. the last one could be considered as the main pollinator, and was seen at regular intervals of 10 to 30 minutes, typical of the trap-lining visiting pattern. c. aurantiacum is a self-compatible species, nevertheless it produces low number of seeds per fruit in self-pollination treatments compared to the natural pollinations promoted by hummingbirds. pipra rubrocapilla (pipridae) and tangara faustuosa (thraupinae) were observed dispersing the fruits of c. aurantiacum. ornithophily predominates in the bromeliaceae, and has been characterised as a parallel evolution mechanism between bromeliads and hummingbirds. canistrum aurantiacum is a typical example of this close relationship.
Larvicidal activity of Cestrum nocturnum on Aedes aegypti  [cached]
Chetan Jawale, Rambhau Kirdak, Laxmikant Dama
Bangladesh Journal of Pharmacology , 2010,
Abstract: Aedes aegypti is a vector parasite of the Dengue. New method to control the population of this insect is necessary. In the present work we evaluated the potential of extract from Cestrum nocturnum as larvicide. Methanol extract outstand as highly active larvicide, achieving 100 % larval mortality in 24 hours when tested in the concentration of 45 μg/mL (soxhlet) and 25 μg/mL (percolation). Any extract exhibiting significant larvicide activity was further fractioned and the fraction tested according to the WHO protocol. One fraction derived from methanol extract present remarkable LC100 at 12 μg/mL. LC50 of methanol extract and active fraction were found 14 μg/mL and 6 μg/mL respectively. These fractions will be submitted to further fractions aiming to identify the molecules responsible for the larvicide activity.
EVALUATION OF ANTI HIV-1 ACTIVITY FROM CESTRUM NOCTURNUM AERIAL PARTS AND PHYTOCHEMICALANALYSIS  [PDF]
KHALED RASHED,XING-JIE ZHANG,MENG-TING LUO,YONG-TANG ZHENG
Reviews of Progress , 2013,
Abstract: This study deals with evaluation of HIV-1 activity from Cestrum nocturnum aerial parts extracts and investigation of phytoconstituents in the plant extracts. Different extracts from Cestrum nocturnum aerial parts, methanol 80%, ethyl acetate, butanol and aqueous extracts were tested for their anti-HIV-1 activity using the syncytia formation assay. All the extracts were weak active as anti-HIV-1 agents. Cestrum nocturnum aerial parts extracts contained saponins, triterpenes and/or sterols flavonoids, tannins and coumarins. The extracts from Cestrum nocturnum aerial parts showed a mild anti-HIV-1 activity.
Biologia reprodutiva de Canistrum aurantiacum E. Morren (Bromeliaceae) em remanescente da Floresta Atlantica, Nordeste do Brasil  [cached]
Siqueira Filho José Alves de,Machado Isabel Cristina S.
Acta Botanica Brasilica , 2001,
Abstract: Canistrum aurantiacum é uma espécie esciófila, epifítica ou terrestre, componente do sub-bosque de mata e endêmica da Floresta Atlantica dos Estados de Pernambuco e Alagoas. Na Reserva Ecológica de Dois Irm os (REDI) (8o7'30"S e 34o52'30"W a ± 80 msm), em Pernambuco, C. aurantiacum forma densa popula o, com período de flora o de novembro a meados de fevereiro, com pico no ínicio de dezembro, quando chega a abrir, num único dia, até doze flores por indivíduo. Suas flores s o tubulosas, com 4 a 5 cm de comprimento. Apresenta síndrome de ornitofilia caracterizada pela antese diurna e ausência de odor nas flores, com corola amarelo-ouro e pela cor vermelha das brácteas involucrais, além do volume e concentra o do néctar variando entre 22,6-40,5ml e 26-33%, respectivamente. O pólen e o estigma est o funcionais durante todo o período de antese, que se inicia por volta das 5:20 h da manh e come am a fechar por volta das 16:00 h. Foram registrados os beija-flores: Chlorostilbon aureoventris e Thalurania watertonii (Trochilinae), Glaucis hirsuta, Phaethornis pretrei e P. ruber (Phaethornitinae). Este último foi observado em intervalos regulares de 10 a 30 min., caracterizando o padr o de visitas do tipo "trap-lining", sendo considerado o principal polinizador da espécie. C. aurantiacum é autocompatível, porém produz baixo número de sementes por fruto nas autopoliniza es em rela o às poliniza es naturais promovidas pelos beija-flores. Pipra rubrocapilla (Pipridae) e Tangara faustuosa (Thraupinae) foram observados dispersando os frutos de C. aurantiacum. A ornitofilia predominante em Bromeliaceae tem sido interpretada como mecanismo de evolu o paralela entre bromélias e beija-flores. Canistrum aurantiacum pode se caracterizar como um exemplo dessa estreita rela o.
Antimicrobial and antioxidant activities of the extracts and compounds from the leaves of Psorospermum aurantiacum Engl. and Hypericum lanceolatum Lam.  [cached]
Tchakam Patricia D,Lunga Paul K,Kowa Théodora K,Lonfouo Antoine Honoré N
BMC Complementary and Alternative Medicine , 2012, DOI: 10.1186/1472-6882-12-136
Abstract: Background Psorospermun aurantiacum and Hypericum lanceolatum are plants locally used in Cameroon and other parts of Africa for the treatment of gastrointestinal and urinary tract infections, skin infections, venereal diseases, gastrointestinal disorder, infertility, epilepsy as well as microbial infections. The present study was designed in order to investigate the in vitro antimicrobial and radical scavenging activities of the extracts and isolated compounds from the leaves of these plants. Methods The plant extract was prepared by maceration in ethyl acetate and methanol and fractionated by column chromatography. The structures of isolated compounds were elucidated by spectroscopic analyses in conjunction with literature data. The broth microdilution method was used to evaluate the in vitro antimicrobial activity against bacteria, yeasts and dermatophytes. The antioxidant potentials of the extracts and their isolated compounds were evaluated using the DPPH radical scavenging method. Results Five known compounds: physcion (1), 1,8-dihydroxy-3-geranyloxy-6-methylanthraquinone (2), kenganthranol B (3), vismiaquinone (4), and octacosanol (5) were isolated from the leaves of P. aurantiacum while six compounds including friedelin (6), betulinic acid (7), 2,2’,5,6’-tetrahydroxybenzophenone (8), allanxanthone A (9), 1,3,6- trihydroxyxanthone (10) and isogarcinol (11) were isolated from H. lanceolatum. Compound 8 and 4 exhibited the highest antibacterial and antifungal activities with MIC ranges of 2–8 μg/ml and 4–32 μg/ml respectively. P. aurantiacum crude extract (Rsa50 = 6.359 ± 0.101) showed greater radical scavenging activity compared with H. lanceolatum extract (Rsa50 = 30.996 ± 0.879). Compound 11 showed the highest radical scavenging activity (RSa50 = 1.012 ± 0.247) among the isolated compounds, comparable to that of L-arscobic acid (RSa50 = 0.0809 ± 0.045). Conclusions The experimental findings show that the ethyl acetate and methanol extracts and isolated compounds from P. aurantiacum and H. lanceolatum stem bark possess significant antimicrobial and antioxidant activities justifying the use of these plants in traditional medicine, which may be developed as phytomedicines.
EVALUATION OF ANTI-HIV-1 ACTIVITY FROM CESTRUM NOCTURNUM AERIAL PARTS AND PHYTOCHEMICAL ANALYSIS  [PDF]
KHALED RASHED,XING-JIE ZHANG,MENG-TING LUO,YONG-TANG ZHENG
Reviews of Progress , 2013,
Abstract: This study deals with evaluation of HIV-1 activity from Cestrum nocturnum aerial partsextracts and investigation of phytoconstituents in the plant extracts. Different extracts fromCestrum nocturnum aerial parts, methanol 80%, ethyl acetate, butanol and aqueous extracts weretested for their anti-HIV-1 activity using the syncytia formation assay. All the extracts wereweak active as anti-HIV-1 agents. Phytochemical analysis of Cestrum nocturnum extracts haveshown the presence of different phytocomponents, saponins, triterpenes and/or sterolsflavonoids, tannins and coumarins. The results confirm that all extracts from Cestrum nocturnumaerial parts have a weak anti-HIV-1 activity.
INVESTIGATION OF ANTIOXIDANT ACTIVITY FROM CESTRUM NOCTURNUM L. STEMS AND PHYTOCHEMICAL CONTENT  [PDF]
KHALED NABIH ZAKI RASHED
Reviews of Progress , 2013,
Abstract: The present study was carried out to evaluate antioxidant activity from extracts of Cestrum nocturnum stems and also investigate the chemical content of the plant extracts. Methanol 8% extract, ethyl acetate, butanol and aqueous extracts were tested for free radical scavenging activity on model reaction with stable 2,2-diphenyl-1-picrylhydrazyl radical (DPPH). The results have shown that Methanol 80% extract is the best one as free radical scavenging agent. Phytochemical analysis of the extracts have shown that methanol 80% extract has flavonoids, saponins, tannins, triterpenes and carbohydrates, both butanol and ethyl acetate extracts have triterpenes and flavonoids while aqueous extract has saponins, carbohydrates and tannins. The results may help to discover new chemical classes of natural antioxidant substances that could serve as selective agents for infectious diseases.Keywords: Cestrum nocturnum, stems, free radical scavenging, phytoconstituents.
Hypomethylation of cytosine residues in cold-sensitive regions of Cestrum strigilatum (Solanaceae)
Guarido, Paula Carolina Paes;Paula, Adriano Alves de;Silva, Carlos Roberto Maximiano da;Rodriguez, Carmen;Vanzela, André Luís Laforga;
Genetics and Molecular Biology , 2012, DOI: 10.1590/S1415-47572012005000026
Abstract: heterochromatin comprises a fraction of the genome usually with highly repeated dna sequences and lacks of functional genes. this region can be revealed by using giemsa c-banding, fluorochrome staining and cytomolecular tools. some plant species are of particular interest through having a special type of heterochromatin denominated the cold-sensitive region (csr). independent of other chromosomal regions, when biological materials are subjected to low temperatures (about 0 °c), csrs appear slightly stained and decondensed. in this study, we used cestrum strigilatum (solanaceae) to understand some aspects of csr condensation associated with cytosine methylation levels, and to compare the behavior of different heterochromatin types of this species, when subjected to low temperatures.
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