Occurrence, Biogenesis, and Synthesis of Biologically Active Carbazole Alkaloids

The breeding of new, high-quality citrus cultivars depends on dependable information about the relationships of taxa within the tribe Citreae; therefore, it is important to have a well-supported phylogeny of the relationships between species not only to advance breeding strategies, but also to advance conservation strategies for the wild taxa. The recent history of the systematics of Citrus (Rutaceae: Aurantioideae) and its allies, in the context of Rutaceae taxonomy as a whole, is reviewed. The most recent classifi cation is tested using nine cpDNA sequence regions in representatives of all genera of the subfam. Aurantioideae (save Limnocitrus ) and numerous species and hybrids referred to Citrus s.l. Aurantioideae are confi rmed as monophyletic. Within Aurantioideae, tribe Clauseneae are not monophyletic unless Murraya s.s. and Merrillia are removed to Aurantieae. Within tribe Aurantieae, the three traditionally recognized subtribes are not monophyletic. Triphasiinae is not monophyletic unless Oxanthera is returned to Citrus (Citrinae). Balsamocitrinae is polyphyletic. Feroniella , traditionally considered allied closely to Limonia (= Feronia ), is shown to be nested in Citrus. The proposed congenericity of Severinia and Atalantia is confi rmed. The most recent circumscription of Citrus is strongly supported by this analysis, with hybrids appearing with their putative maternal parents. The genus was resolved into two clades, one comprising wild species from New Guinea, Australia, and New Caledonia (formerly Clymenia , Eremocitrus , Microcitrus , Oxanthera ), but surprisingly also Citrus medica , traditionally believed to be native in India. The second clade is largely from the Asian mainland (including species formerly referred to Fortunella and Poncirus ).

https://bsapubs.onlinelibrary.wiley.com/doi/pdf/10.3732/ajb.0800341

A molecular phylogeny of the orange subfamily(Rutaceae: Aurantioideae) using nine cpDNA sequences

Sequences of the plastid DNA atpB/rbcL intergenic spacer and rps16 intron from 23 genera and 47 species of Rutaceae were used to resolve phylogenetic relationships in subfamily Aurantioideae. According to these, the subfamily is monophyletic, but its classical subdivision into tribes Clauseneae and Citreae is only justified if the genus Murraya s.s. (exclusive of the species segregated as Bergera, e.g., Murraya koenigii and M. siamensis) and Merrillia are transferred to Citreae s.l. This conclusion is also well supported by phytochemistry, demonstrating accumulation of carbazoles in Bergera and Clausena, and of 8-prenylated coumarins and polyoxygenated flavonoids in Murraya s.s. and Merrillia. Formation of both carbazoles, as well as 8-prenylated coumarins, and polyoxygenated flavonoids in Micromelum suggests relationships between Clauseneae s.s. and Citreae s.l. The monophyly of several larger genera in both tribes is supported by relatively high bootstrap percentages and specific chemical profiles for e.g., Clausena, Micromelum, Glycosmis and Atalantia. In contrast, molecular, chemical, and other data show that none of the subtribes recognized within Aurantioideae reflect phylogenetic relationships. Only the clades with Clausena+Bergera, Murraya s.s. +Merrillia, and Citrus+Clymenia+Eremocitrus+Fortunella+Poncirus (“true Citrus fruit trees”) are well supported by such data. Among the outgroup genera, Zanthoxylum (Rutoideae) and Toddalia (Toddalioideae) are much closer to each other than to Ruta (Rutoideae).

Phylogenetic Analyses of Aurantioideae (Rutaceae) Based on Non‐Coding Plastid DNA Sequences and Phytochemical Features

Mu opioids are among the most widely used drugs for patients with cancer with both acute and chronic pain as well as in the perioperative period. Several retrospective studies have suggested that opioid use might promote tumor progression and as a result negatively impact survival in patients with advanced cancer; however, in the absence of appropriate prospective validation, any changes in recommendations for opioid use are not warranted. In this review, the authors present preclinical and clinical data that support their hypothesis that the mu opioid receptor is a potential target for cancer therapy because of its plausible role in tumor progression. The authors also propose the hypothesis that peripheral opioid antagonists such as methylnaltrexone, which reverses the peripheral effects of mu opioids but maintains centrally mediated analgesia and is approved by the US Food and Drug Administration for the treatment of opioid-induced constipation, can be used to target the mu opioid receptor.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/cncr.29460

Wei-song Kan

Papers

A chemotaxonomic division of Murraya based on the distribution of the alkaloids yuehchukene and girinimbine