Taxonomic revision of Clinacanthus (Acanthaceae) in Thailand

The taxonomy of Clinacanthus in Thailand is revised. Nomenclature, descriptions and a key to the species are provided. Clinacanthus nutans is lectotypified. Clinacanthus burmanni var. robinsoni from Vietnam is found to be distinct from both C. nutans and C. siamensis and is elevated to species status

Recent Green Technologies in Natural Stilbenoids Production and Extraction: The Next Chapter in the Cosmetic Industry

Stilbenoids are well-known phytoalexins in the group of polyphenolic compounds. Because of their potent bioactivities, including antioxidant, antityrosinase, photoprotective, and antibacterial activities, stilbenoids are utilized as pharmaceutical active ingredient in cosmetic products. Thus, the demand for stilbenoids in the cosmetic industry is increasing. The main sources of stilbenoids are plants. Although plants are green and sustainable source materials, some of them do not allow a regular and constant supply due to seasonal and geographic reasons. Stilbenoids typically have been extracted by conventional organic solvent extraction, and then purified by separation techniques. This method is unfriendly to the environment and may deteriorate human health. Hence, the procedures called “green technologies” are focused on novel extraction methods and sustainable stilbenoids production by using biotechnology. In this review, the chemical structures together with the biosynthesis and current plant sources of resveratrol, oxyresveratrol, and piceatannol are described. Furthermore, recent natural deep eutectic solvents (NADES) for green extraction as well as plant cell cultures for the production of those stilbene compounds are updated

Taxonomic Notes on the ‘Mahat’ (Artocarpus lacucha and A. thailandicus, Moraceae) Species Complex in Thailand

‘Mahat’ is a well-known medicinal plant utilized in Thailand. The Thai name ‘Mahat’ has been used in many scientific articles for years. However, it is, unpredictably, a homonym of two scientific names in Flora of Thailand, i.e., A. lacucha and A. thailandicus. Additionally, both species are complex due to their high morphological variation. This causes difficulties in species identification especially when this Thai name is referred to as the scientific name for research publication, quality control of pharmaceutical raw materials, and registration of pharmaceutical products. In this study, we scrutinized the taxonomy of ‘Mahat’ by detailed examination of its morphology and distribution, including molecular and qualitative phytochemical studies. Leaf surfaces were inspected using scanning electron microscopy. The phylogeny of both species was studied using DNA sequences of nuclear and plastid regions. Chromatographic fingerprints, focusing on the major active compound oxyresveratrol, were identified using high-performance liquid chromatography. According to our current study, phylogenetic evidence showed that some samples of both species were clustered together in the same clade and phytochemical fingerprints were almost identical. These results are valuable data for taxonomic revision in the near future and reveal the possible utilization of A. thailandicus as a new material source of oxyresveratrol in the pharmaceutical industry

Enhanced Production of Bryonolic Acid in Trichosanthes cucumerina L. (Thai Cultivar) Cell Cultures by Elicitors and Their Biological Activities

Bryonolic acid is a triterpenoid compound found in cucurbitaceous roots. Due to its biological activities, this compound gets more attention to improve production. Herein, we carried out efficient ways with high bryonolic acid productions from Trichosanthes cucumerina L., a Thai medicinal plant utilizing plant cell cultures. The results showed that calli (24.65 ± 1.97 mg/g dry weight) and cell suspensions (15.69 ± 0.78 mg/g dry weight) exhibited the highest bryonolic acid productions compared with natural roots (approximately 2 mg/g dry weight). In the presence of three elicitors (methyl jasmonate, yeast extract, and chitosan), cell suspensions treated with 1 mg/mL of chitosan for eight days led to higher bryonolic acid contents (23.56 ± 1.68 mg/g dry weight). Interestingly, cell culture and root extracts with high bryonolic acid contents resulted in significantly higher percent cell viabilities than those observed under control (1% v/v DMSO) treatment in Saos-2 and MCF-7 cells. The present study indicated that T. cucumerina L. cell cultures are alternative and efficient to produce the biologically important secondary metabolite

Diversity of Chemical Structures and Biosynthesis of Polyphenols in Nut-Bearing Species

Nuts, such as peanut, almond, and chestnut, are valuable food crops for humans being important sources of fatty acids, vitamins, minerals, and polyphenols. Polyphenols, such as flavonoids, stilbenoids, and hydroxycinnamates, represent a group of plant-specialized (secondary) metabolites which are characterized as health-beneficial antioxidants within the human diet as well as physiological stress protectants within the plant. In food chemistry research, a multitude of polyphenols contained in culinary nuts have been studied leading to the identification of their chemical properties and bioactivities. Although functional elucidation of the biosynthetic genes of polyphenols in nut species is crucially important for crop improvement in the creation of higher-quality nuts and stress-tolerant cultivars, the chemical diversity of nut polyphenols and the key biosynthetic genes responsible for their production are still largely uncharacterized. However, current technical advances in whole-genome sequencing have facilitated that nut plant species became model plants for omics-based approaches. Here, we review the chemical diversity of seed polyphenols in majorly consumed nut species coupled to insights into their biological activities. Furthermore, we present an example of the annotation of key genes involved in polyphenolic biosynthesis in peanut using comparative genomics as a case study outlining how we are approaching omics-based approaches of the nut plant species