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Red/Far Red (R/FR) sensing positively influences the arbuscular mycorrhizal (AM) symbiosis of both legume and nonlegume plants through jasmonic acid (JA) and strigolactone signaling. We previously reported that root exudates obtained from high R/FR-grown plants contained more strigolactone than low R/FR-grown plants. To determine whether JA and JA derivatives were secreted from roots, we investigated the expression levels of JA-responsive genes in L. japonicus Miyakojima MG20 plants treated with root exudates prepared from either high or low R/FR light-treated plants. The root exudates from high R/FR light-treated plants were found to enhance the expression levels of JA-responsive genes significantly. Moreover, exogenous JA increased AM fungal hyphal elongation as did the root exudates derived from high R/FR-grown L. japonicus plants. We conclude that increased JA accumulation and secretion into root exudates from high R/FR light-grown plants is the best explanation for increased colonization and enhanced mycorrhization under these conditions.

Establishment of a nitrogen-fixing symbiosis between legumes and rhizobia not only requires sufficient photosynthate, but also the sensing of the ratio of red to far red (R/FR) light. Here, we show that R/FR light sensing also positively influences the arbuscular mycorrhizal (AM) symbiosis of a legume and a non-legume through jasmonic acid (JA) and strigolactone (SL) signaling. The level of AM colonization in high R/FR light-grown tomato and Lotus japonicus significantly increased compared with that determined for low R/FR light-grown plants. Transcripts for JA-related genes were also elevated under high R/FR conditions. The root exudates derived from high R/FR light-grown plants contained more (+)-5-deoxystrigol, an AM-fungal hyphal branching inducer, than those from low R/FR light-grown plants. In summary, high R/FR light changes not only the levels of JA and SL synthesis, but also the composition of plant root exudates released into the rhizosphere, in this way augmenting the AM symbiosis.

This study targets the evaluation of melanin synthesis inhibition activity of the bamboo shoot skin as agro-waste. The total methanolic extract of bamboo peel extract was evaluated for its skin protective effects via measuring its melanin inhibitory activity and its suppression activity on the expression of tyrosinase mRNA levels. Results showed that bamboo peel extract has a good ability for the inhibition of melanin synthesis so further studies were performed for the isolation of its constituents. Twelve compounds have been isolated from the shoot skin of Phyllostachys pubescens. Their structures were elucidated based on extensive spectroscopic methods. The melanin inhibition potential of the isolates was tested with their collagen-production-promoting activity for the determination of active principles. Results showed that Betulinic acid, tachioside, and 1,2-dilinolenin significantly suppressed melanin production per cell compared to control. Triacontanol, tricin, and (+)-lyoniresinol 9′-O-glucoside also tended to decrease melanin production per cell. These findings indicated that the skin of bamboo shoots, a significant agricultural waste, is a useful natural source for further research on its potential for aging problems such hyperpigmentation and cognitive function impairment. [ABSTRACT FROM AUTHOR]

N-[(3-(3-methyl-1-oxo-butyl)amino)propyl]-3-(3,4-dihydroxyphenyl)prop-2-enamide (7), named 'Bassiamide A', a new alkaloid, together with six known compounds including one lignan (1) and five lignanamides (2–6), were isolated from the aerial parts of Bassia indica Wight. The study also reported an optimal separation of a rare occurring R-isomer lignanamide derivative (6) from a natural origin, in addition to its known corresponding S-isomer (5). Structures of isolated compounds were elucidated based on NMR spectroscopic data, HR-MS, and comparison with known related ones, and they were identified as syringaresinol (1), N-trans-feruloyl-3-methoxytyramine (2), N-trans-feruloyltyramine (3), S-(-)-N-trans-feruloyl normetanephrine (4), S-(-)-N-trans-feruloyl octopamine (5), R-(+)-N-trans-feruloyl octopamine (6). The isolated compounds were evaluated for their anti-acetylcholinesterase activity, and they showed weak inhibitory activity. [ABSTRACT FROM AUTHOR]

New cycloartane-type triterpene 23 R/S-3β-hydroxycycloart-24-ene-23-methyl ether 1a,b (as an C-23 epimeric mixture), along with ten known compounds, including 1 steroid, 3 fatty acids and 6 triterpenoids were isolated from the aerial parts of Euphorbia dendroides L. (Euphorbiaceae). The known compounds (2–11) were identified using 1 D & 2 D-NMR spectra and by comparison with data reported in the literature as well as using GC-MS for the isolated fatty acids. The new compound 1 (a,b) was elucidated by comprehensive 1 D & 2 D NMR experiments as well as LR & HR-FAB-MS. In addition, the isolated cycloartane-type triterpenoids have been tested for in vitro cytotoxicity against different cell lines. The new compound 1 (a,b) exhibited good to weak selective cytotoxic activities against HepG2, Huh-7, KLM-1, 1321N1 and HeLa cell lines with IC50 values of 20.67 ± 0.72, 16.24 ± 0.53, 22.59 ± 0.94, 25.99 ± 0.31 and 40.50 ± 3.14 μM, respectively. [ABSTRACT FROM AUTHOR]