Chemical variability of volatile concentrate from two Ipomoea L. species within a seasonal gradient

In the present study, are extracted volatile concentrate from Ipomoea asarifolia Poir. and Ipomoea setifera (Desr.) Roem. & Schult. in five-month seasonal gradient. The flowers were subjected to simultaneous distillation - extraction (SDE). The chemical composition of the volatile concentrate was determined by gas chromatography (CG/MS) and (CG-FID). Principal Component Analysis (PCA) and Hierarchical Clustering Analysis (HCA) were performed with the chemical constituents. It was observed that the chemical composition of I. asarifolia varied more with seasonality in relation to the species I. setifera. Furthermore, there is a possibility that germacrene D and α-copaene, the main components of the variation volatile of I. asarifolia and with higher concentrations in the rainy months, have ecological importance, attracting specific pollinators for the rainy season. This is the first study to report the chemical composition of the volatile compounds of I. asarifolia and I. setifera along a seasonal gradient.

In silico analyses of toxicity of the major constituents of essential oils from two Ipomoea L. species

Convolvulaceae Juss. is a family of vines and shrubs composed of species of ecological and economic importance. Ipomoea asarifolia (Desr.) Roem. & Schult. and I. setifera Poir. are ruderal and evergreen weeds that invade pastures and cause intoxication in cattle during the dry season. In the present study, the essential oils (EOs) of the leaves from I. setifera (dry season) and I. asarifolia (dry and wet seasons) were obtained by steam distillation for 3h. The chemical composition of the EOs was determined using gas chromatography coupled to gas spectrometry (CG/MS) and gas chromatography with flame ionization detector (CG-FID). To correlate the toxicity of the major chemical constituents of I. setifera and I. asarifolia EOs, we predicted the inhibition activity against the cytochrome P450 (CYP450) and P-glycoprotein 1 (P-gp) using a machine learning-based (ML-based) algorithm. In silico analyses were also applied to evaluate the pharmacokinetics properties related to the penetration in the blood-brain barrier (BBB) and gastrointestinal absorption. The chemical composition of the EO of I. setifera was characterized by high levels of (E)-caryophyllene (36.7%) and β-elemene (20.49%). The I. asarifolia EO showed a phytol derivative as the main chemical constituent in the dry season (35.49%), and its content was reduced in the sample collected during the wet season (10.67%). The constituent (E)-caryophyllene was also present in the leaves of I. asarifolia, but at lower levels (15.93-19.93%) when compared to the EOs of I. setifera. Our computational analyses indicated that the constituents caryophyllene oxide, cedroxyde, pentadecanal, and phytol can be related to the toxicity of these weeds. This is the first study to report the chemical composition of I. asarifolia and I. setifera EOs and correlate their molecular mechanism of toxicity using in silico approaches.