Characterization of Volatile Compounds of Rosa roxburghii Tratt by Gas Chromatography-Olfactometry, Quantitative Measurements, Odor Activity Value, and Aroma Intensity.

Rosa roxburghii tratt (RRT), widely distributed in the southwest of China, is favored by consumers for its good taste and healthy functions. In this study, thirty-seven compounds of Rosa roxburghii Tratt (RRT) were identified and quantified by gas chromatography-olfactometry (G-O) and gas chromatography-mass spectrometry (GC-MS) analysis. Furthermore, ethyl 2-methylpropanoate, ethyl butanoate, ethyl 2-methylbutyrate, and ethyl hexanoate were present with much higher odor activity values (OAVs) than other compounds. The key notes were confirmed by omission tests. Possible interaction among key notes was investigated through odor intensity determination and sensory analysis. It showed fruity and woody notes had synergistic effects. Full factorial design was used to evaluate the notes contribution to the whole odor. One important finding is the major effect of order interactions, fruity note (X1) and woody note (X4) especially, emphasizing the existence of complex interactions occurring between odor notes. The interaction X1X4 was further investigated. The woody note has a positive effect when the fruity note is also in the mixture but tends to show a negative effect otherwise.

Co-delivery of NS1 and BMP2 mRNAs to murine pluripotent stem cells leads to enhanced BMP-2 expression and osteogenic differentiation.

Application of messenger RNA (mRNA) for bone regeneration is a promising alternative to DNA, recombinant proteins and peptides. However, exogenous in vitro transcribed mRNA (IVT mRNA) triggers innate immune response resulting in mRNA degradation and translation inhibition. Inspired by the ability of viral immune evasion proteins to inhibit host cell responses against viral RNA, we applied non-structural protein-1 (NS1) from Influenza A virus (A/Texas/36/1991) as an IVT mRNA enhancer. We evidenced a dose-dependent blocking of RNA sensors by NS1 expression. The co-delivery of NS1 mRNA with mRNA of reporter genes significantly increased the translation efficiency. Interestingly, unlike the use of nucleosides modification, NS1-mediated mRNA translation enhancement does not dependent to cell type. Dual delivery of NS1 mRNA and BMP-2 mRNA to murine pluripotent stem cells (C3H10T1/2), promoted osteogenic differentiation evidenced by enhanced expression of osteoblastic markers (e.g. alkaline phosphatase, type I collagen, osteopontin, and osteocalcin), and extracellular mineralization. Overall, these results support the adjuvant potentiality of NS1 for mRNA-based regenerative therapies. STATEMENT OF SIGNIFICANCE: mRNA therapy has the potential to improve the efficiency of nucleic acid based regenerative medicine. Up to now, the incorporation of expensive modified nucleotides is a common way to avoid IVT mRNA-induced detrimental immunogenicity. We here introduce co-delivery of Influenza virus immune evasion protein-NS1 coding mRNA as a strategy to suppress RNA sensors for maximizing IVT mRNA expression. An increased osteogenic commitment of pluripotent stem cells was observed after BMP2 mRNA and NS1 mRNA delivery. This study revealed how applying non-modified mRNA with NS1 could be a promising alternative as a therapeutic in bone regeneration.

Olfactory impact of esters on rose essential oil floral alcohol aroma expression in model solution.

This study focused on the impact of esters on the perception of floral aroma in rose essential oil. Various aromatic reconstitutions were prepared, consisting of 10 alcohols and 9 esters, all the concentrations found in rose essential oil. Sensory analysis by the triangular tests revealed the interesting behavior of certain compounds among the 9 esters following their addition or omission. The results tend to highlight the important role of ethyl octanoate, ethyl tetradecanoate, citronellyl acetate, geranyl acetate, and 2-phenethyl acetate of esters in rose essential oil. The "olfactory threshold" (OT) of the 5 esters, the floral reconstitution and the mixtures of ester and floral reconstitution were evaluated in alkanes solution. Through the Feller's additive model analysis, it was found that the presence of ethyl octanoate, ethyl tetradecanoate, and citronellyl acetate led to a significant in decrease the OT of the mixtures, whereas geranyl acetate raised the OT. The floral reconstitution in alkanes solution was supplemented with the 5 esters at high, medium, and low concentration, then analyzed by quantitative descriptive analysis. It was revealed that ethyl octanoate, ethyl tetradecanoate, and citronellyl acetate adding overall aroma, and geranyl acetate masking the overall aroma perception in a model floral mixture. Sensory profiles highlighted changes in the perception of aroma nuances in the presence of the 5 esters, with specific perceptive interactions, and reported on the graph based on two parameters [σ = f(τ)]. This paper provided a reference for the flavourists.