Cancer is the leading cause of death worldwide and anticancer drug discovery is a very hot area of research at present. There are various factors which control and affect cancer, out of which enzymes like cyclooxygenase-2 (COX-2) play a vital role in the growth of tumor cells. Inhibition of this enzyme is a very useful target for the prevention of various types of cancers. Alkaloids are a diverse group of naturally occurring compounds which have shown great COX-2 inhibitory activity both in vitro and in vivo. In this mini-review, we have discussed different alkaloids with COX-2 inhibitory activities and anticancer potential which may act as leads in modern anticancer drug discovery. Different classes of alkaloids including isoquinoline alkaloids, indole alkaloids, piperidine alkaloids, quinazoline alkaloids, and various miscellaneous alkaloids obtained from natural sources have been discussed in detail in this review.
Tag: alkaloids
Can climate-driven change influence silicon assimilation by cereals and hence the distribution of lepidopteran stem borers in East Africa?
In East Africa, lepidopteran stemborers such as Chilo partellus and Busseola fusca are major constraints to production of maize, which is the main staple food crop in the region. Cereals depend on silicon (Si)-based defences to fight off herbivores. Using altitudinal ranges in the East African highlands as ecological surrogates for inferring climate change, it was shown that Si concentrations in soil and maize decreased with altitude. This was attributed, in part, to low temperatures at high altitudes, which negatively affected Si assimilation by maize. Experiments showed that B. fusca was more susceptible to Si than C. partellus. Hence the predominance of B. fusca in the highlands and of C. partellus in the lowlands could be partly explained by altitudinal differences in Si concentrations in maize plants. Therefore, a rise in temperature due to climate change should enhance the plants’ Si assimilation and as a result C. partellus might move into the higher altitudes and increasingly displace B. fusca. © 2016 Elsevier B.V.
Variation of alkaloids in the Kenyan Zanthoxylum gilletii (De Wild Waterman)
Zanthoxylum gilletii is an African indigenous deciduous tree which is important for its medicinal use in many communities to treat a wide range of ailments. This study was conducted to identify the alkaloids present in the bark, root and leaves of the Kenyan Z. gilletii. The plant materials were randomly sampled, dried at room temperature, powdered and subjected to thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LC-MS) analyses for the alkaloid confirm atory tests. The bark, root and leaf extract contained peroxysimulenoline, sanguinarine, fagarine I, norchelerythrine (dihydroavicine or demethylnitidine), trans-fagaramide, 8 – methylnorchelerythrine and dihydronitidine alkaloids. The distribution of the alkaloids appeared to be quite variable within different plant parts and different regions. The identified alkaloids have been documented to be useful for their medicinal value in humans and also protect the plants against predation. The medicinal value of Z. gilletii may be due to its contents of varied alkaloids. The information on alkaloidal variation in the species has potential value and practical applications in chemotaxonomy, toxicology and pharmacognosy. The present findings may be useful in optimizing the processing and wild-harvesting of these alkaloids.