RESUMEN
Objective: Cancer is considered as one of the top reasons of death and the number of cases increasing gradually. Cancer is severe clinical difficulty to the health caution system. This study explored two novel polyphenols of Afrocarpus gracilior Pilger growing in Egypt and evaluated their cytotoxic activity. Methods: Methanolic (80%) extract of the leaves of A. gracilior was subjected to column chromatography; the chemical structures of the isolated compounds were established by advanced spectral techniques: UV, 1H, 13C NMR, two dimensional NMR (2D NMR) and electron spray ionization mass spectroscopy (ESI-MS). Compounds 1 and 2 were studied for their cytotoxic activity against hepatocellular carcinoma (Hep-G2) using sulforhodamine B (SRB) assay. Furthermore the pharmacokinetics profiles of these molecules were accessed by employing Petra/Osiris/Molinspiration (POM) analyses. Results: Two novel C-flavonoid glycosides were isolated [1: Apigenin 8-C-β-D-glucopyranosyl-(1```→4``)-O-β-D-glucopyranoside] and [2: 7-O methyl-luteolin 8-C-β-glucopyranosyl-(1```→4``)-O-β-D-glucopyranoside]. They exhibited significant cytotoxic activity (IC50 = 9.02 and 15.61 µg/ml, respectively) against Hep-G2 cells. The POM analyses revealed that the activity of these two compounds depends on the presence of glucosyl and alkyl groups at the internal and terminal atmosphere of the compounds. Conclusion: These findings demonstrated that the leaves of A. gracilior contain a series of bioactive polyphenolic compounds with significant cytotoxic properties against hepatocellular carcinoma and may be used as alternative anticancer agents for doxorubicin. On the basis of POM calculations, it will be interesting to develop some alternative flavones because the deglucosylated derivatives have a better drug score than parent molecules. This preliminary study will be extended to other strains of cancer.
RESUMEN
Los bosques montanos del noroccidente peruano son formaciones vegetales que presentan una alta diversidad y endemismos. Lamentablemente, en muchos lugares están sujetos a procesos acelerados de deterioro por la deforestación y colonización, aspecto que los convierte en uno de los ecosistemas más amenazados por el hombre. Lo que ahora queda de estos bosques, alguna vez extensos, son sólo fragmentos. Los bosques montanos relictos son ecosistemas ubicados por encima de los 1000 m de altitud, en la Vertiente Occidental de los Andes. Es en estos bosques, donde se pueden encontrar especies de coníferas nativas de nuestro país, pertenecientes a la familia Podocarpaceae. Estas especies juegan un rol de suma importancia en la dinámica de estos ecosistemas tan frágiles; no obstante, debido a la calidad de sus maderas, están siendo extraídas de manera alarmante. En el noroccidente peruano existen zonas de bosques homogéneos de Podocarpáceas tal es el caso del bosque de Cachil en la provincia de Contumazá, bosque de Tongod-Quellahorco en la provincia de San Miguel (en los cuales predomina la especie Podocarpus oleifolius) y los bosques de San Ignacio en Cajamarca, en los que reportamos cinco especies de Podocarpáceas distribuidas en tres géneros: Podocarpus (P. oleifolius, P. macrostachys, P sprucei), Prumnopitys (P. harmsiana) y Nageia (N. rospigliosii), las cuales representan el 50% del total de especies reportadas para el Perú.
The montane forests of north-western Peru are plant formations with high biodiversity and numerous endemic taxa. Unfortunately, in many places, they are deteriorated by deforestation and colonization processes, to turning into one of the most threatened ecosystems of the world. At the present, montane forests are reduced to isolated fragments. The relict forests are distributed above 1000 m on the western slope of the Andes. These forests are habitat for Peruvian native coniferous of the Podocarpaceae family. These species are supporting the fragility of montane forests ecosystems, however they are being cut down in large numbers because of the excellent timber quality. There are some forests largely dominated by Podocarpaceae in north-western Peru, we have the Cachil forest (Cajamarca, Province Contumazá) and Tongod-Quellahorco (Cajamarca, Province San Miguel) which are dominated by Podocarpus oleifolius. The San Ignacio forests (Cajamarca, Province San Ignacio) where we find half the species known from Peru, there are five species from three genera: Podocarpus oleifolius, P. macrostachys, P. sprucei, Prumnopitys harmsiana and Nageia rospigliosii.
RESUMEN
AIM:To study the chemical constituents of the root bark of Podocarpus milanjianus Rendle.METHOD:Isolation and elucidation of the chemical constituents were conducted by chromatography and spectral evidences.RESULTS:Nine compounds,isolated from the root bark of P. milanjianus,were identified as nagilactone D ( 1), nagilactone G (2), nagilactone F (3), podolactone C (4), totarol (5), 19-hydroxytotarol (6), β-sitosterol (7), daucosterol (8) and stigmasterol (9),on the basis of spectral data and physical constants. Among them, compounds 1,2,7,8,9 were isolated from this species for the first time.