Lagochilus

Abstract: Two flavanones, 5,2′,6′-trihydroxy-7,8-dimethoxyflavanone (1), 5,2′,6′-trihydroxy-6,7,8-trimethoxyflavanone (2) and their 2′-O-β-D-glucosides (3, 4), and a neoclerodane-type diterpene, 15-demethoxyscupolin I (5), together with twenty-eight known compounds were isolated from the extracts of Lagochilus leiacanthus. The structures of the new compounds were determined by spectroscopic means. The two new flavanones and some known flavonoids showed the inhibitory activity on the release of β-hexosaminidase from RBL-2H3 cells.

Abstract: Phytochemical investigations on the 95% ethanolic extract of the aerial parts of Lagochilus ilicifolius offered 7 iridoid glucosides,2 aliphatic alcohols,1 diterpene,and 1 phenylpropanoid.Their structures were identified to be 8-O-acetylharpagide(1),ajugoside(2),ajujol(3),harpagide(4),geniposidic acid(5),mussaenosidic acid(6),8-deoxyshanzhiside(7),citrusin C(8),phytol(9),12-hentriacontanol(10),and octacosanol(11) on the basis of spectroscopic data interpretation and chemical comparison.Compounds 2~3 and 5~11 were isolated from the genus Lagochilus for the first time.

Abstract: The high-mountain ecosystems of Central Asia are a biodiversity hotspot with unique plant communities and many endemic species. Intense human pressure and global warming have caused habitat destruction in these areas and a parallel increase in the number of endangered species. Lagochilus species are key medicinal herbaceous plants native to Central Asia, many of which have been recently added to the endangered of species in Uzbekistan. To assess the climate sensitivity of Lagochilus species, we (1) located populations of six species in their native sites across Uzbekistan, and assessed their health by partitioning to ontogenetic stages along five consecutive years; (2) collected plant materials from these species, as well as from old herbarium samples (1918–1964); and (3) analyzed the carbon-13 composition in those samples, as an indicator for drouht stress. Over the course of five years (2014–2018) of continuous monitoring, fluctuations in annual precipitation in the region indicated a decrease by ∼20 %, and the fraction of young plants in each population decreased from 20–50% to 0–5 %, depending on the species. Comparing the carbon-13 composition in current and historical leaf samples showed an increase of 1.5–3.5‰ associated with a decrease in precipitation of 2–30 %, depending on the site and species. Our results show the high sensitivity of Lagochilus populations’ regeneration to drying, among six species and in sites across Uzbekistan. On a multi-decadal temporal scale, the dramatic changes in carbon-13 indicate that the response to precipitation reduction is related with drought stress. Considering the expectation for drier and hotter climate in Uzbekistan in the coming decades, conservation of Lagochilus populations should become a priority in Central Asia.

Abstract: The modern status of rare species on the Ustyurt Plateau is evaluated. New coenotic populations of two species (Malacocarpus crithmifolius (Retz.) C. A. Mey. and Euphorbia sclerocyathium Korov. et M. Pop.) registered in the Red Data Book are revealed. Their status is assessed by the ontogenetic structure. The distribution pattern of some rare species growing on the Kara-Kalpak part of the Ustyurt Plateau (Crambe edentula, Lagochilus acutilobus, Crataegus korolkowii, and Allium delicatulum) that are not listed in the Red Data Book of Uzbekistan, is characterized.