scholarly journals New alkaloids from Ocotea duckei vattimo (Lauraceae)

2021 ◽  
Vol 10 (4) ◽  
pp. e28910412800
Author(s):  
Laisla Rangel Peixoto ◽  
Josean Fechine Tavares ◽  
Yuri Mangueira do Nascimento ◽  
Augusto Lopes Souto ◽  
Raimundo Braz Filho ◽  
...  

Ocotea duckei Vattimo, popularly known as “louro-de-cheiro”, “louro-pimenta”, and “louro-canela”  is a member of the Lauraceae family found in the Northeast region of Brazil. It is popularly used to treat neuralgia, dyspepsia, anorexia and pain. This current study aimed to promote the isolation and the identification / determination of new secondary metabolites of the species O. duckei Vattimo. In order to obtain the vegetable drug of O. duckei, its stem barks were harvested and submitted to a drying process followed by pulverization. The Crude Ethanolic Extract (BSE), obtained from the vegetable drug, was then subjected to an alkaloid extraction protocol in order to generate its Total Alkaloid Fraction (TAF). The isolation and identification of chemical compounds were carried out by chromatographic and spectroscopic methods respectively. The chemical investigation of O. duckei resulted in the isolation of three compounds: Ocoteaduccin A (OD-1, 0.020 g), Ocoteaduccin B (OD-2, 0.015 g), and N-methylcoclaurine (OD-3, 0.008 g). O. duckei proved to be a promising species, due to the variety of isolated chemical compounds. Further chemical, pharmacological and toxicological studies must be conducted in order to improve the phytochemical knowledge about this plant.

2021 ◽  
pp. 1-9
Author(s):  
Abdou Sarr ◽  
Serigne Ibra Mbacké Dieng ◽  
Kady Diatta-Badji ◽  
Amadou Ibrahima Mbaye ◽  
William Diatta ◽  
...  

Background : Stereospermum kunthianum Cham., is a medicinal plant from the Bignoniaceae family, used in Ferlo (Senegal) against stomach aches, as a healing agent and aphrodisiac.Aims/Objective : The aim of this study was to contribute to the valorisation of the plant by carrying out a phytochemical screening followed by an assay of the polyphenols of the hydro-ethanolic extract of the bark and its fractions.Methods : Phytochemical screening was carried out by coloring and/or precipitation reactions. The total polyphenol and tannin contents were evaluated by the Folin-Denis method and the flavonoid content by a method using aluminium chloride (AlCl 3 ) and sodium nitrite (NaNO 2 ). Results: The search for chemical compounds revealed the presence of various secondary metabolites such as gallic and catechic tannins, flavonoids, saponosides, alkaloids, sterols and polyterpenes. The total polyphenol contents of the samples ranged from 0.81 ± 0.02 to 13.52 ± 0.06 mg EAT / g. Those of tannins and flavonoids were between 0.03 ± 0.01 and 4.56 ± 0.02 mg EAT / g and between 1.13 ± 0.04 to 31.88 ± 0.19 mg ER / g respectively.Conclusion : These different metabolites would be responsible for the activities noticed for this plant.


Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2521 ◽  
Author(s):  
Larissa Silva ◽  
Jovelina Alves ◽  
Emerson da Silva Siqueira ◽  
Manoel de Souza Neto ◽  
Lucas Abreu ◽  
...  

Genipa americana is a medicinal plant popularly known as “jenipapo”, which occurs in Brazil and belongs to the Rubiaceae family. It is a species widely distributed in the tropical Central and South America, especially in the Cerrado biome. Their leaves and fruits are used as food and popularly in folk medicine to treat anemias, as an antidiarrheal, and anti-syphilitic. Iridoids are the main secondary metabolites described from G. americana, but few studies have been conducted with their leaves. In this study, the aim was to chemical approach for identify the main compounds present at the extract of G. americana leaves. The powdered leaves were extracted by maceration with EtOH: water (70:30, v/v), following liquid-liquid partition with petroleum ether, chloroform, ethyl acetate and n-butanol. A total of 13 compounds were identified. In addition three flavonoids were isolated from the ethyl acetate fraction: quercetin-3-O-robinoside (GAF 1), kaempferol-3-O-robinoside (GAF 2) and isorhamnetin-3-O-robinoside (GAF 3) and, from n-butanol fraction more two flavonoids were isolated, kaempferol-3-O-robinoside-7-O-rhamnoside (robinin) (GAF 4) and isorhamnetin-3-O-robinoside-7-rhamnoside (GAF 5). Chemical structures of these five flavonoids were elucidated using spectroscopic methods (MS, 1H and 13C-NMR 1D and 2D). These flavonoids glycosides were described for the first time in G. americana.


2008 ◽  
Vol 3 (8) ◽  
pp. 1934578X0800300 ◽  
Author(s):  
Solomon Habtemariam

Activity-directed fractionation and isolation procedures were used to identify the antioxidant components of Peltiphyllum peltatum. Fresh leaves were extracted with ethanol and subsequently fractionated into light petroleum, chloroform, ethyl acetate, n-butanol, and water fractions. The ethyl acetate fraction, which showed the strongest antioxidant activity, was subjected to Sephadex LH-20 chromatography, followed by repetitive preparative TLC, to afford the major antioxidant principle, quercitrin, together with other antioxidants (isoquercitrin, catechin and gallate) as minor principles. The identities of the isolated compounds were established by spectroscopic methods (1D and 2D NMR and MS) and by direct comparison with authentic samples and literature values. Quercitrin displayed a potent protective effect of DNA from UV generated hydroxyl radical damage.


2019 ◽  
Vol 4 (2) ◽  
pp. 263-277
Author(s):  
Evana - Evana ◽  
Pratiwi Pratiwi ◽  
Ahmad Fathoni ◽  
Oscar Efendi ◽  
Andria Agusta

 Giant forest ant Dinomyrmex gigas is one of the largest ants species in the world, native to the rain forests of Southeast Asia. It is known that ants have glands that produce chemical compounds that inhibit the growth of microbes. Therefore, it is necessary to deter-mine the antioxidant and antibacterial activities as well as identify the chemical compounds of D. gigas extract. D. gigas was extracted successively with n-hexane, ethanol and methanol. The antioxidant activity was evaluated by determination of the half-maximal inhibi-tory concentration (IC50) values while the antibacterial activities of the extracts were determined by measuring the minimum inhibitory concentration (MIC). The results exhibited that the IC50 values of n-hexane, ethanolic and methanolic extracts were 336.18±0.0984, 89.16±0.0219 and 90.72±0.0894 μg/mL respectively. The ethanolic extract exhibited the highest AAI value (0.34) followed by metha-nolic extract (0.33) and n-hexane extract (0.09). Based on AAI val-ues, the extracts were classified as moderate antioxidants. The best MIC values were 625 μg/mL for both ethanolic and methanolic ex-tracts against S. aureus, while MIC values of all extracts against E. coli were >625 μg/mL. Based on MIC values, all of the extracts presented weak activity against both S. aureus and E.coli. The GC-MS analysis showed that there are up to 30 compounds construct-ed of the ethanolic extract. Three major compounds are ethyl oleate  (29.78%), n-hexadecanoic acid (17.54%) and oleic acid (10.65%). 


2016 ◽  
Vol 1 ◽  
pp. 47-54
Author(s):  
Maya Vergolyas

There was considered the use of biotesting for the assessment of the quality of drinking water from the different water supply sources (artesian, packaged and water-pipe one). The method consists in determination of the toxicants action on the specially selected organisms in the standard conditions with registration of changes at behavior, physiological, cellular and subcellular level using hematological indices of fish, frogs, rats and the lymphocyte cultures of the peripheral human blood. Physical-chemical methods determine only the presence and number of chemical elements in the tested water samples because of the very large number of possible combinations of chemical compounds in water solutions (more than 75 million combinations), including behavior of anthropogenic compounds and the natural vulnerability of the water ecosystems to the combined effects from its toxic influence. As the optimal set of determination of the some structural and functional changes of cell genome as the result of the toxic influence of combination of the chemical compounds in the water solutions was offered the micronuclear test and leukocytic formula of the fish, frog and rat blood as biomarker. The reaction of fish, frog, rat test-organisms on the toxic irritation is presented in the change of qualitative content of the cells of peripheral blood. There were demonstrated the prospects of the use of hematological indices of the following test-organisms: Danio rerio fishes, Xenopus clawed frogs, Wistar rats and also the lymphocytes cultures of the human peripheral blood. The special attention was paid to the assessment of the risk for human health of the toxic substances in drinking water, genotoxicity and cytotoxicity that are revealed using hematological indices of animal cells. The universality of cellular organization opens the wide possibilities for toxicological studies using peripheral blood of the different groups of animals (fish, frogs, rats), human lymphocyte cultures and allow assume the following possibility of extrapolation of the received results on human organism


2018 ◽  
Vol 20 (5) ◽  
pp. 411-418 ◽  
Author(s):  
Bernadett Kovacs ◽  
Zoltán Béni ◽  
Miklós Dékány ◽  
Noémi Bózsity ◽  
Istvan Zupko ◽  
...  

1997 ◽  
Vol 36 (11) ◽  
pp. 101-106 ◽  
Author(s):  
January Bien ◽  
Lidia Wolny

Studies of sewage sludge conditioning by ultrasonic field concentrate on determination of the increase of water removal effect, which depends on kind of sludge and chemical compounds used in the dewatering process. An attempt was made to find new methods of sludge preparation before dewatering. Tests presented here focused on digested and difficult dewatered sludge. The sludge was dewatered on a vacuum filter after conditioning with polyelectrolytes and the ultrasonic field. The microscopic analysis was an additional criterion to evaluate changes in the sludge structure after preparation. The polyelectrolyte dose of 3 mg/g d.m. sonicated within 15 sec. resulted in the 50% decrease of sludge volume. Results presented confirmed our previous experiences, concerning the relation between conglomerates of sludge and the effect of dewatering.


1981 ◽  
Vol 46 (12) ◽  
pp. 3063-3073 ◽  
Author(s):  
Jana Podlahová ◽  
Bohumil Kratochvíl ◽  
Vratislav Langer ◽  
Josef Šilha ◽  
Jaroslav Podlaha

The equilibria and mechanism of addition of protons to the ethylenediphosphinetetraacetate anion (L4-) were studied in solution by the UV, IR, 1H and 31P NMR spectroscopic methods. A total of six protons can be bonded to the anion. They are added stepwise, first with partial formation of zwitterions containing P-H bonds, which then dissociate with formation of the free acid, H4L, where all four protons are bonded in carboxyl groups. The formation of zwitterions is strongly dependent on the concentration. In the final stage, the acid bonds two additional protons to form the bis-phosphonium cation, H6L2+. A number of isostructural salts containing this cation, H4L.2 HX (X = Cl, Br, I), have been prepared. The X-ray crystal structure determination of the bromide confirmed the expected arrangement. The bromide crystals are monoclinic, a = 578.2, b = 1 425.0, c = 1 046.7 pm, β = 103.07° with a space group of P21/c, Z = 2. The final R factor was 0.059 based on 1 109 observed reflections. The structure consists of H6L2+ cations containing protons bonded to phosphorus atoms (P-H distance 134 pm) and of bromide anions, located in gaps which are also sufficiently large for I- anions in the isostructural iodide. The interbonding of phosphonium cations proceeds through hydrogen bonds, C-OH...O=C, in which the O...O distance is 275.3 pm.


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