Pentacyclic triterpenoids and other constituents isolated from the leaves of Gambeya lacourtiana and their antibacterial activity

The phytochemical study was done on the leaves of Gambeya lacourtiana. This plant has been used in traditional medicine to treat of different ailments such as uterine heamorrhage, metritis and other vaginal infections. Chromatographic fractionation and purification on the leaves crude extract afforded lupeol acetate (1), lupenone (2), lupeol (3), taraxerol (4) stigmasterol (5), erythrodiol (6), chamaedrydiol (7), methyl pheophorbide-a (8), corosolic acid (9), tormentic acid (10), epicatechin (11) and 22-dihydrospinasterol 3-O-β-D-glucopyranoside (12). The structures of compounds 1–12 were elucidated on the basis of 1D and 2D NMR, mass spectrometric and the spectroscopic data as well as comparison with the literature. Compounds 4, 7–10 and 12 were isolated for the first time from Gambeya genus. Crude extract, fractions and compounds 6–12 were evaluated for their antibacterial activity. Methyl pheophorbide-a (8) demonstrated moderate activity against Salmonella typhi CPC with MIC values of 62.5 μg/mL. The chemophenetic significance of these compounds is also discussed.     

Possible chemotaxonomic significance of the occurrence of cis-4-hydroxy-l-proline in santalaceae

cis-4-hydroxy-l-porline was detected in three genera (four species) of Santalaceae.     

Triterpenoids and sterols from seeds of Phytolacca esculenta

Chromatographic separation of the chloroform-soluble part of the methanol extract from Phytolacca esculenta seeds resulted in the isolation of acetylaleuritolic acid, 3-acetylmyricadiol, α-spinasterol and stigmast-7-en-3β-ol.     

Identification of ergoline alkaloids in the genus Argyreia and related genera and their chemotaxonomic implications in the convolvulaceae

The results of the identification of 21 ergoline alkaloids of 14 species of Argyreia; viz.: A. barnesii, A. capitata, A. cuneata, A. luzoninsis, A. mollis, A. maingayi, A. nervosa, A. obtusifolia, A. philippinensis, A. reticulata. A. ridleyi, A. rubicunda, A. splendens and A. sp. and 2 closely related genera; Stictocardia tiliafolia and Rivea corymbosa, by using 2-D TLC procedures are given. A brief discussion of the implications of the ergoline alkaloids and the chemotaxonomy of the Convolvulaceae is also presented.     

Triterpenoids from Mangifera indica

From the neutral fraction of the n-hexane extract of stem bark of Mangifera indica, (var./cv Banganpalli) six new tetracyclic triterpenoids, cycloart-24-ene-3β,26-diol, the C-24 epimers of cycloart-25-ene-3β,24,27-triol, the C-24 epimers of cycloartane-3β,24,25-triol and 3-ketodammar-24E-ene-20S,26-diol together with the known compounds cycloartenol, α-amyrin, β-amyrin, sitosterol 3β-hydroxycycloart-25-en-26-al, dammarenediol II, the C-24 epimers of cycloart-25-ene-3β,24-diol, 24-methylenecycloartane-3β,26-diol, ψ-taraxastane-3β,20-diol and ocotillol II have been isolated. The acidic fraction of the same extract, on esterification with diazomethane followed by chromatography, yielded methyl mangiferonate, methyl isomangiferolate, methyl mangiferolate and the diazomethane adduct of methyl mangiferolate. The structures were elucidated by spectroscopic and chemical methods.     

Triterpenoids from the seedpods of Holarrhena curtisii King and Gamble

Two new hydroperoxy pentacyclic triterpenoids, 3β-hydroxy-11α-hydroperoxyolean-12-en-28-oic acid (1) and 3β-hydroxy-11α-hydroperoxyursan-12-en-28-oic acid (2), together with nine known triterpenoids, squalene (3), β-amyrin acetate (4), α-amyrin acetate (5), lupeol acetate (6), lupeol (7), lanosta-7,24-dien-3β-ol (8), cycloeucalenol (9), oleanolic acid (11) and ursolic acid (12), a known phytosterol, 24-methylenepollinastanol (10), and two known flavanols, (–)-catechin (13) and (–)-gallocatechin (14), were isolated from the methanolic extract of the fresh seedpods of Holarrhena curtisii. Their structures were determined by spectroscopic analysis (one and two dimensional nuclear magnetic resonance, high resolution electrospray ionization mass spectrometry and attenuated total reflectance-Fourier transform infrared spectroscopy). All compounds (except squalene) were evaluated for their in vitro α-glucosidase inhibitory activity. Compounds 1, 2, 11 and 12, which had a pentacyclic triterpenoid acid skeleton, showed a strong in vitro α-glucosidase inhibitory activity compared to that of the standard control, acarbose.     

Triterpenoids of Terminalia sericea

The structures of sericic acid and sericoside, the major constituents of the roots of Terminalia sericea, have been determined. Sericic acid is 2α,3β,19α,24-tetrahydroxy-olean-12-en-28-oic acid and sericoside the corresponding C-28 D-glucosyl ester.     

Triterpenoids of Lycopodium megastachyum

Eight triterpenes of the serratane type have been isolated from Lycopodium megastachyum Baker. They are serratenediol, 21-epi-serratenediol, serratenediol-3-acetate, 21-epi-serratenediol-3-acetate, lycoclavanol, tohogenol diacetate, phlegmanol-D and serratenonediol diacetate.     

Triterpenoids from Rosa odorata Sweet var. gigantea (Coll.et Hemsl.) Rehd.et Wils and their chemotaxonomic significance

Thirty-three reported compounds were obtained for the first time from Rosa odorata Sweet var. gigantea (Coll.et Hemsl.) Rehd. et Wils and were all identified as triterpenoids. The structure of these compounds was determined by physicochemical constants and spectral analyses (NMR, MS). This is the first report on four compounds (7, 9, 10 and 22) from the family Rosaceae and thirteen compounds (2, 3, 4, 11, 17, 19, 20, 23, 24, 26, 29, 31 and 33) from the genus Rosa. Finally, the chemotaxonomic significance of these compounds is discussed.     

Meconic acid as a chemotaxonomic marker in the papaveraceae

Of 48 species of Papaveraceae examined representing 12 genera, 24 were shown to contain meconic acid and of these, 21 were Papaver species. Meconopsis cambrica was also found to contain meconic acid, in contrast to other species of Meconopsis examined. One recent rearrangement of the Papaveraceae includes a grouping of Papaver, Roemeria and Stylomecon together with M. cambrica and our further discovery of meconic acid in two Roemaria species examined leads to the conclusion that meconic acid may be a distinctive taxonomic feature of this new grouping. Some attempt has also been made to correlate meconic acid occurrence with that of certain types of alkaloids, and of chelidonic acid.     

Evaluation of the viability and germination of tempisque [<i>Sideroxylon capiri</i> (A.DC.) Pittier Sapotaceae]

The tempisque (Sideroxylon capiri) is a tree native to Mexico used by the rural population for housing construction, poles and hedges, as fuel (wood) and also for fodder and ornamental purposes, among others. It is considered an endangered species. In order to contribute to its preservation and sustainable management, it was considered important to determine the proportion of viable seeds, the loss of viability due to storage period and the germination process by applying pregerminative treatments. We found that freshly collected seeds showed 100% viability, which decreased to 0% after 5 months of storage. According to the cumulative germination significant differences between treatments (p≤0.01) were found. It was observed that seeds can accelerate their time of germination with the previous exposure of 24 h in water at room temperature. The soaking treatment in water for 24 h at room temperature obtained final germination of 55%, while with the control 39% was reached. Soaking in hydrogen peroxide and scarification were the treatments with lower germination percentage (33 and 23%, respectively). To get a higher percentage of germinated seeds in a short time, it is necessary to give a soaking treatment in water for 24 h before sowing.