The Chemical Structure and Bioactivity of Cycloartane-type Compounds

Recent reports in the biggest herbal genus, Astragalus, in Iran; with a special viewpoint on tragacanth gum production

This comprehensive review was carried out to integrate all the data published in the electronic databases (Scopus, etc.) over the past two decades about the distribution, phytochemistry, ethnopharmacology, and pharmacology of Astragalus L. Although Astragalus is one of the largest genera of flowering plants in Iran, limited phytochemical screening of this genus has been reported. Cycloartane triterpene glycosides, labdane diterpenoids, flavonoids, and polysaccharides are the major identified compounds. Pharmacological studies revealed significant properties such as anti-inflammatory, anticancer, antidiabetic, etc. Moreover, ethnopharmacological studies of Astragalus sp. showed that this genus is used for gastrointestinal, fractures, joint pains, and skin problems in different localities of Iran. Tragacanth gum, as the main product of some Astragalus sp. with economic value, shows proper biological activities and uses as an emulsifier in food industries. This review might be helpful for researchers to find new chemical entities responsible for its claimed traditional uses and food supplements.

Enhancement of Phytosterol and Triterpenoid Production in Plant Hairy Root Cultures-Simultaneous Stimulation or Competition?

Plant in vitro cultures, including hairy roots, can be applied for controlled production of valuable natural products, such as triterpenoids and sterols. These compounds originate from the common precursor squalene. Sterols and triterpenoids distinctly differ in their functions, and the 2,3-oxidosqualene cyclization step is often regarded as a branch point between primary and secondary (more aptly: general and specialized) metabolism. Considering the crucial role of phytosterols as membrane constituents, it has been postulated that unconstrained biosynthesis of triterpenoids can occur when sterol formation is already satisfied, and these compounds are no longer needed for cell growth and division. This hypothesis seems to follow directly the growth-defense trade-off plant dilemma. In this review, we present some examples illustrating the specific interplay between the two divergent pathways for sterol and triterpenoid biosynthesis appearing in root cultures. These studies were significant for revealing the steps of the biosynthetic pathway, understanding the role of particular enzymes, and discovering the possibility of gene regulation. Currently, hairy roots of many plant species can be considered not only as an efficient tool for production of phytochemicals, but also as suitable experimental models for investigations on regulatory mechanisms of plant metabolism.

Antiviral Activity of Jamaican Medicinal Plants and Isolated Bioactive Compounds

Plants have had historical significance in medicine since the beginning of civilization. The oldest medical pharmacopeias of the African, Arabian, and Asian countries solely utilize plants and herbs to treat pain, oral diseases, skin diseases, microbial infections, multiple types of cancers, reproductive disorders among a myriad of other ailments. The World Health Organization (WHO) estimates that over 65% of the world population solely utilize botanical preparations as medicine. Due to the abundance of plants, plant-derived medicines are more readily accessible, affordable, convenient, and have safer side-effect profiles than synthetic drugs. Plant-based decoctions have been a significant part of Jamaican traditional folklore medicine. Jamaica is of particular interest because it has approximately 52% of the established medicinal plants that exist on earth. This makes the island particularly welcoming for rigorous scientific research on the medicinal value of plants and the development of phytomedicine thereof. Viral infections caused by the human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2), hepatitis virus B and C, influenza A virus, and the severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) present a significant global burden. This is a review of some important Jamaican medicinal plants, with particular reference to their antiviral activity.