Genetic Diversity and Chemical Profile of Rhodophiala bifida Populations from Brazil

Rhodophiala bifida (Herb.) Traub, Amaryllidaceae, is a species native to South America known to produce alkaloids with potential pharmacological uses such as montanine, which has anti-inflammatory potential. R. bifida could be applied as a natural source of montanine. It is important to understand the genetic diversity of this species in order to assess the sustainable use of this plant. The aim of this study was to evaluate the genetic diversity and chemical profiles of the two known natural populations of R. bifida in Brazil. This report is the first population genetic study of R. bifida. We studied 93 individuals with six Inter-Simple Sequence Repeats (ISSR) primers. A total of 79 loci were amplified. Our results showed high-population structure (Fst = 0.16), with greatest genetic variation at the intrapopulation level. Genetic analyses separated the individuals of R. bifida into two clusters that corresponded to each of the natural populations. Chemical profile evaluation was carried out on dried bulbs, leaves, flowers, and flower scapes by liquid chromatography and mass spectrometry. Montanine and nangustine were the main metabolites identified in both populations. These alkaloids concentrations differed by population and by plant part

N-oxide alkaloids from Crinum amabile (Amaryllidaceae)

Natural products play an important role in the development of new drugs. In this context, the Amaryllidaceae alkaloids have attracted considerable attention in view of their unique structural features and various biological activities. In this study, twenty-three alkaloids were identified from Crinum amabile by GC-MS and two new structures (augustine N-oxide and buphanisine N-oxide) were structurally elucidated by NMR. Anti-parasitic and cholinesterase (AChE and BuChE) inhibitory activities of six alkaloids isolated from this species, including the two new compounds, are described herein. None of the alkaloids isolated from C. amabile gave better results than the reference drugs, so it was possible to conclude that the N-oxide group does not increase their therapeutic potential

Amaryllidaceae alkaloids : identification and partial characterization of montanine production in Rhodophiala bifida plant

Rhodophiala bifida (R. bifida) is a representative of the Amaryllidaceae plant family and is rich in montanine, an alkaloid with high pharmaceutical potential. Despite the interest in these compounds, many steps of the biosynthetic pathway have not been elucidated. In this study, we identified the alkaloids produced in different organs of R. bifida under different growth conditions, set up the conditions for in vitro R. bifida regeneration and initiated the molecular characterization of two R. bifida genes involved in alkaloids biosynthesis: the Norbelladine 4′-O-Methyltransferase (RbN4OMT) and the Cytochrome P450 (RbCYP96T). We show that montanine is the main alkaloid produced in the different R. bifida organs and developed a direct organogenesis regeneration protocol, using twin-scale explants cultivated on media enriched with naphthalene acetic acid and benzyladenine. Finally, we analyzed the RbN4OMT and RbCYP96T gene expressions in different organs and culture conditions and compared them to alkaloid production. In different organs of R. bifida young, adult and regenerated plants, as well as under various growing conditions, the transcripts accumulation was correlated with the production of alkaloids. This work provides new tools to improve the production of this important pharmaceutical compound and for future biotechnological studies

Root exudation of oxalic acid in Lotus corniculatus in response to aluminum toxicity

The objective of this research was to identify the existence of root exudation of organic acid in Lotus corniculatus germplasms subjected to toxic aluminum (Al) levels and investigate the effect of this mechanism on the Al content in the root tissue and in morphological parameters of plant development. Two experiments were performed in nutrient solution to evaluate the Al accumulation and exudation of organic acids, using cultivars INIA Draco and São Gabriel and genotypes UFRGS and UF-T2. The plants were cultivated in Al-free solution, which was applied on the 45th day in half of the pots of each genotype. Root exudation was highly correlated with the reduced accumulation of Al in the root tissue (r2 = 0.75 at 72 h). Genotype UF-T2, selected for Al tolerance, extruded 80% more oxalic acid in the presence of Al compared with the other germplasms, indicating that this mechanism is involved with Al tolerance in L. corniculatus. This experiment showed strong evidence that L. corniculatus exhibits Type I tolerance, in which anionic channels are rapidly activated by Al exposure. Exudation of oxalic acid is likely a crucial mechanism that allows the maintenance of L. corniculatus growth when exposed to toxic Al conditions, and this characteristic should be used to identify tolerant genotypes in the future

Atividade quimiotáxica de extratos de folhas de espécies do gênero Psychotria

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Antimicrobial activity of alcoholic and aqueous extracts of M. hirsutissima and M. vaccinifolia

Os extratos alcoólico e aquoso de M. hirsutissima e M. vaccinifolia foram avaliados para uma possível atividade antimicrobiana contra microorganismos Gram+ e Gram-. Somente os extratos de M. hirsutissima mostraram uma moderada atividade contra S. aureus.The possible antimicrobial activity of alcoholic and aqueous extracts M. hirsutissima and M. vaccinifolia was evaluated against Gram+ and Gram- microorganisms. Only the extracts M. hirsutissima exhibited a moderate activity against S. aureus

Chemical composition of volatile oil from Psidium cattleyanum, P. guaiava, P. incanum and P. luridum (Myrtaceae)

Óleos voláteis de folhas de Psidium cattleyanum (araçá), P. guaiava (goiaba), P. incanum (araçá-do-campo) e P. luridum (araçá-do-campo), coletadas no Rio Grande do Sul, foram obtidos por hidrodestilação e analisados através de CG e CG/EM. Os rendimentos em óleo volátil (p/V) variaram de 0,2% a 0,4%. 0 óleo de P. cattleyanum apresentou como constituinte majoritário beta-cariofileno (36,8%) e óxido de cariofileno (9,0%). Em P. guaiava observou-se a presença de beta-cariofileno (16,7%), alfa e beta-selineno (17,2% e 20,9%, respectivamente), e alfa-cadinol (11%). P. incanum e P. luridum foram caracterizados pela presença predominante de 1,8-cineol (33,6% e 45,7%, respectivamente), alfa-terpineol (10,6% e 14,4%, respectivamente) e alfa-pineno (15,5% e 8,2%, respectivamente).Volatile oils from Psidium cattleyanum (araçá), P. guaiava (goiaba), P. incanum (araçá-do-campo) and P. luridum (araçá-do-campo), collected in Southern Brazil, were obtained by hydrodistillation and analyzed by CG and CG/MS. The yield of the volatile oil ranging from 0.2 to 0.4%. The oil from P. cattleyanum showed beta-caryophyllene predominance (36.8%) followed by caryophyllene oxyde (9.0%). In P.R guaiava beta-caryophyllene were identified (16.7%), alpha and beta-selinene (17.2% and 20.9%, respectively) and alpha-cadinol (11%). P. incanum and P. luridum were characterized by predominance of 1,8-cineole (33.6% and 45.7%,, respectively), alpha-terpineol (10.6% and 14.4%, respectively) and alpha-pinene (15.5% and 8.2%, respectively)

Hippeastrum reticulatum (Amaryllidaceae) : alkaloid profiling, biological activities and molecular docking

The Amaryllidaceae family has proven to be a rich source of active compounds, which are characterized by unique skeleton arrangements and a broad spectrum of biological activities. The aim of this work was to perform the first detailed study of the alkaloid constituents of Hippeastrum reticulatum (Amaryllidaceae) and to determine the anti-parasitological and cholinesterase (AChE and BuChE) inhibitory activities of the epimers (6 -hydroxymaritidine and 6 -hydroxymaritidine). Twelve alkaloids were identified in H. reticulatum: eight known alkaloids by GC-MS and four unknown (6 -hydroxymaritidine, 6 -hydroxymaritidine, reticulinine and isoreticulinine) by NMR. The epimer mixture (6 -hydroxymaritidine and 6 -hydroxymaritidine) showed low activity against all protozoan parasites tested and weak AChE-inhibitory activity. Finally, a molecular docking analysis of AChE and BuChE proteins showed that isoreticulinine may be classified as a potential inhibitory molecule since it can be stabilized in the active site through hydrogen bonds, - stacking and hydrophobic interactions

Análise mutagênica de alcalóides extraídos de plantas da família das Amaryllidaceae em Saccharomyces cereviseae

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Processos de obtenção do extrato do trevo-vermelho enriquecido com isoflavonas e seu uso via oral como anti-inflamatório

Hospital de Clínicas de Porto AlegreUniversidade Federal do Rio Grande do SulFarmáciaAgronomiaMedicinaDepositad