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α-Cembrenediol displays a diverse array of biological activities, encompassing antibacterial, antitumor, and neuroprotective effects. To comprehensively understand the in vivo transport, distribution, and elimination mechanisms associated with α-cembrenediol, its interaction with bovine serum albumin (BSA) was investigated. In this study, the interaction between α-cembrenediol and BSA was explored using various techniques, including UV absorption, steady-state fluorescence, circular dichroism spectrum, molecular docking, and molecular dynamics simulation. The results showed that there was a clear interaction between BSA and α-cembrenediol. Specifically, the KSV and Kb decreased with increasing temperature at 293, 303, and 310 K, indicating that α-cembrenediol interacted with BSA through a static quenching mechanism. Furthermore, the number of binding sites was approximately 1 at the three temperatures, suggesting the presence of a single specific binding site for α-cembrenediol on BSA. Moreover, the binding process occurred spontaneously (ΔG<0), primarily driven by hydrogen bonds and van der Waals forces (ΔH<0 and ΔS<0). α-Cembrenediol bound to the Sudlow site I of BSA. Binding of BSA to α-cembrenediol also caused its conformation to change. This study provides essential insights into the interaction between α-cembrenediol and BSA, contributing to a better understanding of the pharmacokinetic properties of the compound. [ABSTRACT FROM AUTHOR]

Lindera glauca is a shrub or small tree mostly distributed in China, Japan and Korea. However, reports on the biological activities of Lindera glauca fruit essential oil (LGFEO) are limited. The study on its chemical composition, and antioxidant and cholinesterase inhibitory activities were performed, along with molecular docking of six selected compounds. The LGFEO was extracted by hydro distillation and analyzed by GC-MS and GC-FID. Antioxidant activities of LGFEO were evaluated by three methods with different mechanisms. Acetylcholinesterase and butyrylcholinesterase inhibitory activities of LGFEO were tested. A total of 48 components were identified representing 95.74% of the total composition of LGFEO in which the major compounds were (E)-β-ocimene (41.53%), α-copaene (13.17%), δ-cadinene (6.20%), 3-carene (5.89%) and eucalyptol (3.57%). Weak antioxidant activities of LGFEO in three assays (9.52, 11.36 and 38.98 μmol TE/g, respectively) were observed. LGFEO showed obvious cholinesterase inhibitory activities at the final concentrations of 50 and 20 μg/mL. IC50 values for acetylcholinesterase and butyrylcholinesterase were 46.48 and 34.85 μg/mL, respectively. Molecular docking revealed that geranyl acetate, β-caryophyllene and limonene had lower binding affinities in the range of −7.1 to −6.1 kcal/mol through hydrophobic interactions and hydrogen bond. Six compounds including 3-carene, limonene, eucalyptol, (E)-β-ocimene, geranyl acetate and β-caryophyllene could contribute together to cholinesterase inhibitory activities of LGFEO. This essential oil indicated low potential as natural antioxidant, but it could be potentially used as cholinesterase inhibitor with possible application in food, aromatherapy and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

In order to clarify the mechanisms behind the contents of glucose, free amino acids and Amadori compounds in tobacco leaves and their correlations during flue-curing, the variations of these compounds in middle leaves of K326 and Bina 1 before and after curing were analyzed by adopting the half-leaf sampling. The conversion rates of six free amino acids to Amadori compounds and their differences between the two cultivars were compared. The results showed that : 1) The total amounts of glucose and free amino acids of the two cultivars increased significantly after flue-curing. The increase of the total amount of free amino acids was mainly due to the substantial increase in the content of proline, the contents of different amino acids varied greatly with different change trends. Six Amadori compounds formed during flue-curing, and the variation trends of their contents were consistent with the overall trend of free amino acid contents in the flue-cured tobacco leaves. The content of Amadori compound converted from alanine was the highest, followed by proline, and that from leucine was the lowest. 2) The conversion rates of different free amino acids to Amadori compounds differed significantly in the flue-cured tobacco leaves : alanine was the highest, valine was the second and proline was the lowest. There were also significant differences between the two cultivars : the conversion rates of five free amino acids (alanine, proline, valine, leucine and tryptophan) in Bina 1 were significantly higher than those in K326. Thus it could be seen that the contents of Amadori compounds in the flue-cured tobacco leaves were affected by the contents of free amino acids and the Maillard reaction activity, and the differences of the hereditary characters between the cultivars also affected the conversion of the Maillard reactions and the contents of Amadori compounds in the two types of flue-cured tobacco leaves. [ABSTRACT FROM AUTHOR]

A Myriad of biotic and abiotic factors inevitably affects the growth and production of tobacco (Nicotiana tabacum L.), which is a model crop and sought-after worldwide for its foliage. Among the various impacts the level of disease severity poses on plants, the influence on the dynamics of phyllospheric microbial diversity is of utmost importance. In China, recurring reports of a phyto-pathogen, Didymella segeticola , a causal agent of tobacco leaf spot, accentuate the need for its in-depth investigation. Here, a high-throughput sequencing technique, IonS5TMXL was employed to analyze tobacco leaves infected by D. segeticola at different disease severity levels, ranging from T1G (least disease index) to T4G (highest disease index), in an attempt to explore the composition and diversity of phyllospheric microbiota. In all healthy and diseased tobacco leaves, the most dominant fungal phylum was Ascomycota with a high prevalence of genus Didymella , followed by Boeremia , Meyerozyma and Alternaria , whereas in the case of bacterial phyla, Proteobacteria was prominent with Pseudomonas being a predominant genus, followed by Pantoea. The relative abundance of fungi, i.e., Didymella and Boeremia (Ascomycota) and bacteria, i.e., Pseudomonas and Pantoea (Proteobacteria) were higher in diseased groups compared to healthy groups. Healthy tissues exhibited relatively rich and diverse fungal communities in contrast with diseased groups. The infection of D. segeticola had a complex and significant effect on fungal as well as bacterial alpha diversity. FUNGuild analysis indicated that the relative abundance of pathotrophs and saprotrophs in diseased tissues proportionally increased with disease severity. PICRUSt analysis of diseased tissues indicated that the relative abundance of bacterial cell motility and membrane transport-related gene sequences elevated with an increase in disease severity from T1G to T3G and then tended to decrease at T4G. Conclusively, the current study shows the typical characteristics of the tobacco leaf microbiome and provides insights into the distinct microbiome shifts on tobacco leaves infected by D. segeticola. [ABSTRACT FROM AUTHOR]