N. glutinosa L. is a relatively less studied Nicotiana species (Solanaceae), although there are data about its importance as a model plant in viral control studies, as a gene donor in tobacco hybridization and as a source of agents with insecticidal or fungicidal effects. The biological activities of the species were associated mostly with the presence of leaf surface metabolites, in particular diterpenes and sucrose esters. The aim of this study was to identify the chemical composition of the essential oil (EO) and two aromatic extraction products (concrete and resinoid) obtained from N. glutinosa L. leaves. GC-MS analysis identified 26 components in the EO (representing 97.3% of total oil content), which contained mostly diterpene compounds with major components manool (14.2%), sclarene (8.4%) and manoyl oxide (8.1%). The number of compounds identified in the concrete was 37 (95.5% of the total content) and the major component was the diterpene alcohol sclareol (14.2%). In the resinoid, 30 volatile components (representing 95.1% of resinoid content) were identified, with major components nicotine (32.9%), α-tocopherol (8.2%), tridecanoin (6.9%), sclareol (6.9%), and solanone (6.9%). The group of bicyclic diterpenes had the largest share in the diterpene fraction of the products (57.3%, 91.7%, and 86.3%, respectively for the EO, concrete, and resinoid). Considering the abundance of sclareol in the aromatic products, the antimicrobial activity of the pure substance was determined. Sclareol was highly effective against a set of medicinally important yeasts; Candida albicans АТСС 10231, C. glabrata ATCC 90030, C. parapsilosis clinical isolate, and C. tropicalis NBIMCC 23, while being less effective against the studied Gram-positive and Gram-negative bacteria. Data from the study on N. glutinosa aromatic products composition may be of interest to the aroma industries for their possible use in perfumery and cosmetics.

The genus Nicotiana (Solanaceae) includes over 70 species, with a long history of traditional use; many of them are nowadays used in bioengineering, biosynthesis, molecular biology, and other studies, while common tobacco, N. tabacum L., is one of the most economically important industrial crops worldwide. Although Nicotiana species have been extensively investigated, relatively less research has focused on flowers, especially research related to obtaining aromatic products for cosmetic and perfumery use. On the other hand, there is evidence that Nicotiana flowers accumulate various secondary metabolites with a distinct aroma and biological activities, and the flowers represent a biomass available in sufficient quantities. Therefore, this study aimed to determinate the chemical composition (by GC-MS) and the olfactory profiles of a specific type of natural aromatic product (concrete), obtained from the flowers of four Nicotiana species, in a direct comparison between them. The yields of extracted concrete were sufficiently high, varying between the species, 1.4% (N. rustica L.), 2.5% (N. glutinosa L.), 1.6% (N. alata Link&Otto genotype with white flowers), 2.7% (N. alata genotype with pink flowers), 3.2% (N. tabacum, Oriental type), and 5.2% (N. tabacum, Virginia type). The major components of the obtained concretes belonged to different chemical classes: N. rustica and N. tabacum (OR), the hydrocarbons n-tetratriacontane (14.5%; 15.0%) and n-triacontane (12.1%; 13.3%), and 3-methyl-pentanoic acid (11.1%; 12.2%); N. glutinosa, the diterpenes sclareol (25.9%), 3-α-hydroxy-manool (16.3%), and 13-epimanool (14.9%); N. alata (WF), the phenylpropanoid terephthalic acid and di(2-ethylhexyl) ester (42.9%); N. alata (PF), the diterpene tributyl acetylcitrate (30.7%); and N. tabacum (FCV), the hydrocarbons n-hexacosane (12.9%) and n-pentacosane (12.9%). Each of the flower concretes revealed a characteristic odor profile. This is the first report about Nicotiana species as a source for obtaining flower concretes; these initial results about the concrete yield, olfactory profile, and chemical composition are a prerequisite for the possible processing of Nicotiana flowers into new aromatic products for use in perfumery and cosmetics. The study provides new data in favor of the potential of the four Nicotiana species as aromatic plants, as well as a possible alternative use of flowers, a valuable, but discarded, plant material in other applications.

In the modern market of tobacco products worldwide, there is a trend towards increased consumption and trade in cut tobacco for manual rolling of cigarettes (RYO tobacco), including and from unregulated producers. This hides additional risks for the health of the consumers due to the possibility to use low-quality and uncontrolled raw materials, including and with increased presence of pathogenic and conditionally pathogenic microorganisms. The aim of the study was to determine the total amount of heterotrophic bacteria (microbial count), the amount of microscopic fungi and the most common species in the raw material for tobacco RYO, distributed on the Bulgarian market. The microbiological analyzes were performed by classical methods accepted in sanitary microbiology. In all samples, spores of the genus Bacillus showed mass development, and according to the macro-morphological characteristics of the colonies, the predominant species can be attributed to B. cereus. The detected amounts of microscopic fungi in the tested tobacco mixtures were significant at strong presence of species of the genus Aspergillus, over 85.48%. Macroscopically, species were defined as A. flavus (41.94%), A. niger (27.42%) and A. fumigatum (16.13%). The relative share of species of the genus Penicillium was 9.68% and of species of the genus Mucor -4.84%. The studied tobacco raw material for manual rolling of cigarettes had significant contamination by microorganisms that had the rank of pathogens. Quantitative microbial assessment suggests a potential health risk for consumers.

A sustainable economy and the drive to reduce agro-industrial waste worldwide motivate the increased interest in alternative uses of traditionally cultivated plants such as tobacco. Tobacco seeds are an underutilized resource with enormous potential for application in various areas of human life. The present study aims to characterize the phytochemical composition and nutritional potential of Oriental tobacco seeds grown in Bulgaria, in order to support their possible application in areas outside the tobacco industry. Two Oriental tobacco varieties (“Krumovgrad 90” and “Krumovgrad 58”) from three production regions were explored and comparatively evaluated in terms of their physical and chemical indicators, determined by standardized methods. The results showed high protein (22.57–23.84%) and energy content (482–531 kcal/100 g), combined with relatively low carbohydrate levels (3.79–4.03%) and the presence of bioactive compounds, such as polyphenols (288–357 mg GAE/100 g). The seeds contained significant amount of oil (36.31–39.24%), of which the fatty acid profile included 16 identified components, with linoleic (72.0–74.4%), oleic (11.2–13.5%), palmitic (9.6–10.2%), and stearic (1.8–2.5%) acids taking the greatest share. The sterol fraction was dominated by β-sitosterol (43.5–46.8%), followed by sitostanol, campesterol and stigmasterol, with a stable distribution between the samples. The main tocol was γ-tocotrienol (56.5–61.4%), with α-tocotrienol being detected only in one of the varieties (“Krumovgrad 58”, 13.3%). The phospholipid fraction showed variations between the samples, with a dominant presence of phosphatidylinositol (18.0–20.4%). The results from the study confirmed the tangible potential of tobacco seeds as a source of biologically active substances in the development of functional foods and dietary supplements.

The increased consumption of roll-your-own (RYO) cigarettes and water pipe (hookah), both globally and in Bulgaria, necessitated the current investigation aimed at the assessment of heavy metal levels in the tobacco blends used in those products. The concentrations of Mn, Zn, Cu, Cd, Pb, and Ni were determined by AAS in five brands of RYO tobacco (R1-R5) and seven brands of water pipe tobacco (W1- W7), all distributed on Bulgarian market. The average heavy metal contents (mg/kg) in the two types of tobacco blends, RYO and water pipe, respectively, were as follows: Mn - 214.20 and 37.89; Zn - 31.90 and 134.87; Cu - 12.06 and 10.07; Cd - 0.80 and 1.33; Pb - 1.60 and 3.57; Ni - 1.36 and 0.80. RYO cigarette tobaccos contained higher concentration of Mn, Cu and Ni, while water pipe tobaccos - Zn, Cd and Pb. Strong correlations were found between Cu and Zn (r=0.81), Cu and Cd (r=0.90) in RYO tobacco blends, and between Cu and Zn (r=0.86) - in water pipe blends, respectively. The results from the study give reason to recommend that this information be provided to the consumers, who consider the regarded tobacco products as a safer alternative to conventional cigarettes.

The research was conducted on 18 samples of RYO tobacco. The density (CFU/g a.d.s.) of three heterotrophic groups of microorganisms and some physical-chemical indicators were determined. The analyses were performed according to classic methods. Quantitative and qualitative changes at the microbiome as a result of disruption of homeostasis in microbial communities and development of secondary succession in the direction of intensive mineralization processes were found. Statistically significant correlation dependences with the physical-chemical parameters were registered. In addition to a potential risk in term of sanitary-hygiene and health aspects, the changes also have a negative impact on the consumer qualities of tobacco blends.