A Study of the Chemical Composition, Antioxidant Potential, and Acute Toxicity of Bulgarian Tanacetum vulgare L. Essential Oil.

Common tansy (Tanacetum vulgare L.) is a plant with medicinal properties that has traditionally been used in folk medicine for its anthelmintic, antispasmodic, and choleretic effects, for the treatment of diarrhea and digestive problems, and externally, as an insecticide in veterinary practices. In the current study, we investigated, for the first time, the chemical profile and antioxidant activity of essential oil from a wild population of T. vulgare L. growing in Bulgaria. Common tansy essential oil (EO), which is rich in bicyclic monoterpenes, was obtained using hydrodistillation and characterized by using gas chromatography-mass spectrometry (GC-MS). Thirty-seven compounds were identified in Bulgarian tansy EO. Among the major constituents were oxygenated monoterpenes, including compounds such as camphor (25.24%), trans-chrysantenyl acetate (18.35%), cis-verbenol (10.58%), thujone (6.06%), eucaliptol (5.99%), and α-campholenal (5.98%). The analysis results identified the essential oil from T. vulgare L. grown in the western Rhodope Mountains of Bulgaria as the camphor chemotype. Furthermore, its antioxidant activity was analyzed using the oxygen radical absorbance capacity (ORAC) method and was found to be 605.4 ± 49.3 µmol TE/mL. The essential oil was also tested for single-dose acute toxicity on Wistar rats and was found to be non-toxic by oral administration. The mean lethal dose by intraperitoneal administration was LD50 i.p. = 14.9 g/kg body weight. The results of the conducted study can serve as a basis for the evaluation and subsequent exploration of other pharmacotherapeutic effects of the essential oil obtained from the inflorescences of the Bulgarian species T. vulgare L.

A Study of the Chemical Composition, Acute and Subacute Toxicity of Bulgarian Tanacetum parthenium Essential Oil.

BACKGROUND: Tanacetum parthenium (L.) Sch.Bip. (T. parthenium) is an aromatic perennial plant belonging to the Asteraceae family, also known as feverfew. It is widely distributed in various regions of Europe and other parts of the world. The plant has a rich background in the traditional medicine of many nations and has been used as a remedy for fever, pain, inflammation, asthma, rheumatism, menstrual disorders, etc. Methods: GC-MS analysis was conducted to determine the chemical composition of the isolated essential oil (EO). Using the method proposed by Litchfield and Wilcoxon, the average lethal dose (LD50) of the EO on Wistar rats was determined for two routes of administration: oral (p.o.) and intraperitoneal (i.p.). The subacute toxicity of the EO was also tested by oral administration of a daily dose of 1.0 g/kg body weight (BW) for 28 days. The toxicity of the EO was evaluated by observing and evaluating changes in behavior, body weight, basic hematological and serum biochemical parameters, and histopathological changes of the internal organs. RESULTS: Thirty-seven volatile organic compounds representing 94.58% of the total oil composition were tentatively detected in the obtained T. parthenium EO. The dominant compounds were camphor (45.47%), trans-chrisantenyl acetate (21.65%), camphene (9.48%), and cis-isogeraniol (5.42%). The results showed that the EO was not toxic when administered in acute oral doses. The acute mean lethal dose for intraperitoneal administration was LD50 i.p. = 2.13 g/kg BW. In the subacute study involving administration of an oral dose of EO for 28 days, there were a number of changes in the hematological and serum biochemical parameters of the blood compared with the control group of animals. However, no symptoms of toxicity, changes in the body weight of the rats, death, or pathological changes in the histological indicators of the examined organs-brain, heart, stomach, liver, spleen and kidney-were found. Extrapolating the results obtained from the rat experiments, we can state that the EO is safe for use in doses below 1 g/kgBW for a period not exceeding one month.

Characteristics of patients with severe asthma in primary and secondary care settings considered eligible for biological therapy - the Bulgarian RECOGNISE study.

INTRODUCTION: Asthma is a major non-communicable disease. It affects both children and adults, but is the most common chronic condition among the former. While inhaled controller drugs stabilize the disease in most asthma patients, there are a certain number of people who suffer from severe asthma, which requires treatment escalation. Oral corticosteroids are usually added, but they are associated with various side effects that may limit their application. The introduction of biologicals targeting inflammatory mediators has opened a new era of asthma treatment highlighting the importance of patient characterization.

A study of flavonoid composition and antimicrobial activity of Scutellaria altissima L. from different floristic regions of Bulgaria.

INTRODUCTION: Scutellaria extracts and its constituents, especially the characteristic flavonoids such as baicalein and its glycoside baicalin, exhibit significant antimicrobial activity. AIM: To perform a comparative analysis of flavonoid composition and antimicrobial activity of extracts obtained from aerial parts and roots of Scutellaria altissima from the regions of Mezek and Bachkovo, Bulgaria. MATERIALS AND METHODS: 70% ethanol and aqueous extracts of aerial parts and roots of S. altissima were used. HPLC analysis of S. altissima extracts was performed. Microbiological tests were done on clinical isolates of Streptococcus mitis, Staphylococcus aureus, Escherichia coli, and Candida albicans. Minimal bactericidal and minimal bacteriostatic concentrations of S. altissima extracts were determined by the agar method. RESULTS: The ethanol extracts contain flavonoids approximately twice as much in comparison with the aqueous extracts. The baicalin content in the aerial parts of S. altissima from the region of Mezek is 5 times higher than that in the roots. S. altissima extracts have effective antimicrobial activity against S. mitis only. The minimal bactericidal concentration of ethanol extracts of S. altissima aerial parts and S. altissima roots is 2000 µg/ml and 8000 µg/ml at 24 hours, respectively. The bactericidal effect of aqueous extracts occurs at 48 hours at minimal bactericidal concentration of S. altissima aerial parts - 2000 µg/ml and of S. altissima roots - 6000 µg/ml. CONCLUSIONS: The finding that extracts of Bulgarian S. altissima possess effective antimicrobial properties against S. mitis suggests that it can be used as a potential source for the development of natural antimicrobial agents to suppress oral pathogens and prevent some oral infections.

URANIUM AND 210PO RADIONUCLIDES IN DRINKING WATER IN SOUTHERN BULGARIA AND EXPECTED RADIATION DOSES.

The activity concentrations of the naturally occurring radionuclides 238U, 234U and 210Po have been determined for the first time in drinking water from certain sources in Southern Bulgaria using nuclear and radiochemical methods. The results obtained for the water samples vary in the intervals 0.6-678 mBq l-1 for 238U, 1.4-1484 mBq l-1 for 234U, <0.3-13.6 mBq l-1 for 210Po and 1.04-10.6 for the 234U/238U ratio. The annual effective dose from 238U, 234U and 210Po ranges from 1.09 to 44.1 µSv y-1, 0.78 to 46.8 µSv y-1 and 0.77 to 62.8 µSv y-1 for infants, children and adults, respectively. The annual effective dose due to consumption of drinking water is below the individual dose criterion of 100 µSv y-1 recommended by the World Health Organization. The natural radioactivity of the water sources investigated is below the national and international limits.

High resolution LC-MS/MS characterization of polyphenolic composition and evaluation of antioxidant activity of Sambucus ebulus fruit tea traditionally used in Bulgaria as a functional food.

The purpose of this study was to perform phytochemical analysis of tea from Sambucus ebulus fruits concerning hydroxycinnamic acids, flavonol glucosides, stilbenes and proanthocyanidin mono-, di- and trimers content. In total, 33 compounds were identified and quantified using UPLC-DAD-ESI/MS/MS system and the results are presented in mg/g dry weight (DW). Among analyzed hydroxycinnamic acids, 5-Caffeoylquinic acid (114.17 mg/g) was most abundant, followed by 3-p-Coumaroylquinic acid (50.33 mg/g) and 3-p-Feruloylquinic acid, p-Coumaric acid glucoside and 4-p-Coumaroylquinic acid (31.36 mg/g, 29.78 mg/g and 27.70 mg/g, respectively). Flavonol glucosides were represented predominantly by Quercetin-3-O-galactoside, Quercetin-3-O-rhamnosyl-galactoside Quercetin-3-O-glucoside and Quercetin-3-O-rhamnosyl-glucoside (3.68 mg/g, 3.22 mg/g, 2.87 mg/g and 2.56 mg/g, respectively). trans-Resveratrol-3-O-glucoside, epicatechin (40.62 mg/g) and proanthocyanidin di- and -trimers (19.90 mg/g - 31.42 mg/g) also were present in the tea. ABTS cation decolorization assay revealed 1.248 mM UAE activity and the percent of DPPH radical scavenging was 14.25%, corresponding to 39.07 µM Trolox equivalents.

Pollen and Chemical Content of Beebreads from Serpentine Areas in Albania and Bulgaria.

Beebread from serpentine localities in Albania and Bulgaria were characterized based on their pollen and chemical element content (macroelements K, Ca, Mg, P and microelements Cd, Co, Cr, Cu, Fe, Mn, Na, Ni, Pb, Zn) aiming to (1) evaluate the effect of serpentine soil on the quality of beebread; (2) compare elemental concentrations in samples from serpentine areas in Albania and Bulgaria; and (3) compare the differences in pollen spectra. Chemical element content was determined using microwave digestion of beebread samples followed by ICP-OES measurements. The analytical procedure developed was validated by added/found method. Analytical figures of merit of analytical method proposed were presented. The melissopalynological analysis was applied for pollen characterization. The results demonstrate clear difference in the pollen spectra between the two sets of samples, confirming differences in local serpentine flora in both countries, but specific pollen type is difficult to be suggested. The pollen content is related to the flowering period, climatic conditions, and bees forage preferences. The samples vary in their elemental concentrations depending on the pollen type and year of collection. The highest average concentrations found for K, Ca, Mg, and P are close to values reported in the literature. However, elevated concentrations observed for Ni, Cr, Mn, and Fe in beebread, especially from Albania, are in line with the serpentine characteristics of studied areas. The concentrations of Cd and Pb for all beebread samples are below permissible limits. The results should be taken into consideration in future specific food safety regulations at national and international level.

Essential Oil Composition and Bioactivity of Two Juniper Species from Bulgaria and Slovakia.

Juniperus excelsa M. Bieb and J. sabina L. contain essential oil (EO), while J. sabina also contains podophyllotoxin, which is used as a precursor for anti-cancer drugs. Two studies were conducted. The first assessed the variability in the EO profile and podophyllotoxin concentration of the two junipers, depending on the location and tree gender. The main EO constituents of J. excelsa were α-cedrol, α-limonene and α-pinene, while the constituents in J. sabina were sabinene, terpinen-4-ol, myrtenyl acetate and α-cadinol. The podophyllotoxin yield of 18 J. sabina accessions was 0.07-0.32% (w/w), but this was not found in any of the J. excelsa accessions. The second study assessed the effect of hydrodistillation (Clevenger apparatus) and steam distillation (in a semi-commercial apparatus) on the EO profile and bioactivity. The extraction type did not significantly alter the EO composition. The EO profiles of the two junipers and their accessions were different and may be of interest to the industry utilizing juniper leaf EO. Breeding and selection programs could be developed with the two junipers (protected species) in order to identify chemotypes with (1) a high EO content and desirable composition, and (2) a high concentration of podophyllotoxin in J. sabina. Such chemotypes could be established as agricultural crops for the commercial production of podophyllotoxin and EO.

Analysis of the Household and Health Care System Expenditures in Bulgaria.

Health care systems worldwide are experiencing tremendous financial pressure because of the introduction of new targeted health technologies and medicines. This study aims to analyze and compare public and household healthcare expenditures in Bulgaria during the period 2015-2019, as well as present the major cost-containment measures implied by the government and their probable influence on the overall health care cost. Regulatory analysis of the endorsed cost-containment measures, budget analysis of public and household health care expenditures, and their extrapolations were performed. The regulatory analysis reveals that a large number of measures are introduced and valid until January 2021, considering pharmaceuticals, medical devices, and negotiations between the National Health Insurance Fund (NHIF) and Marketing authorization holders (MAHs). NHIF costs due to pharmaceuticals, food supplements, and medical devices are rising from 2015 to 2019. The overall health expenditures average per household and the average per person also grow in this period. The cost extrapolation reveals that an increase in 3-year periods is expected. Despite the implementation of variety of cost-containment measures in Bulgaria, such as HTA, ERP, discounts, and annual negotiations, The National Health Insurance Fund's (NHIF) spending on pharmaceuticals continues to rise in recent years, and further increases are expected in the next 3 years. The average expenditure per household and per person also increased, which confirms the global trend of rising medicine and outpatient services value.

GC-MS Metabolic Profile and α-Glucosidase-, α-Amylase-, Lipase-, and Acetylcholinesterase-Inhibitory Activities of Eight Peach Varieties.

The inhibition of certain digestive enzymes by target food matrices represents a new approach in the treatment of socially significant diseases. Proving the ability of fruits to inhibit such enzymes can support the inclusion of specific varieties in the daily diets of patients with diabetes, obesity, Alzheimer's disease, etc., providing them with much more than just valuable micro- and macromolecules. The current study aimed atidentifying and comparing the GC-MS metabolic profiles of eight peach varieties ("Filina", "Ufo 4, "Gergana", "Laskava", "July Lady", "Flat Queen", "Evmolpiya", and "Morsiani 90") grown in Bulgaria (local and introduced) and to evaluate the inhibitory potential of their extracts towards α-glucosidase, α-amylase, lipase, and acetylcholinesterase. In order to confirm samples' differences or similarities, principal component analysis (PCA) and hierarchical cluster analysis (HCA) were also applied to the identified metabolites. The results provide important insights into the metabolomic profiles of the eight peach varieties and represent a first attempt to characterize the peels of the peach varieties with respect to α-glucosidase-, α-amylase-, lipase-, and acetylcholinesterase-inhibitory activities. All of the studied peach extracts displayed inhibitory activity towards α-glucosidase (IC50: 125-757 mg/mL) and acetylcholinesterase (IC50: 60-739 mg/mL), but none of them affected α-amylase activity. Five of the eight varieties showed inhibitory activity towards porcine pancreatic lipase (IC50: 24-167 mg/mL). The obtained results validate the usefulness of peaches and nectarines as valuable sources of natural agents beneficial for human health, although further detailed investigation should be performed in order to thoroughly identify the enzyme inhibitors responsible for each activity.

Initial Upper Palaeolithic humans in Europe had recent Neanderthal ancestry.

Modern humans appeared in Europe by at least 45,000 years ago1-5, but the extent of their interactions with Neanderthals, who disappeared by about 40,000 years ago6, and their relationship to the broader expansion of modern humans outside Africa are poorly understood. Here we present genome-wide data from three individuals dated to between 45,930 and 42,580 years ago from Bacho Kiro Cave, Bulgaria1,2. They are the earliest Late Pleistocene modern humans known to have been recovered in Europe so far, and were found in association with an Initial Upper Palaeolithic artefact assemblage. Unlike two previously studied individuals of similar ages from Romania7 and Siberia8 who did not contribute detectably to later populations, these individuals are more closely related to present-day and ancient populations in East Asia and the Americas than to later west Eurasian populations. This indicates that they belonged to a modern human migration into Europe that was not previously known from the genetic record, and provides evidence that there was at least some continuity between the earliest modern humans in Europe and later people in Eurasia. Moreover, we find that all three individuals had Neanderthal ancestors a few generations back in their family history, confirming that the first European modern humans mixed with Neanderthals and suggesting that such mixing could have been common.

Therapeutic Success of Tiotropium/Olodaterol, Measured Using the Clinical COPD Questionnaire (CCQ), in Routine Clinical Practice: A Multinational Non-Interventional Study.

BACKGROUND: The Clinical COPD Questionnaire (CCQ) is a simple patient-reported tool to measure clinical control of chronic obstructive pulmonary disease (COPD). OBJECTIVE: This open-label, single-arm, non-interventional study (NCT03663569) investigated changes in CCQ score during treatment with tiotropium/olodaterol in clinical practice. METHODS: Data were included from consenting COPD patients, enrolled in Bulgaria, Czech Republic, Hungary, Israel, Lithuania, Poland, Romania, Russia, Slovenia, Switzerland and Ukraine, who were receiving a new prescription for tiotropium/olodaterol according to the treating physician in a real-world environment. The primary endpoint was the occurrence of therapeutic success, defined as a 0.4-point decrease in CCQ score after treatment with tiotropium/olodaterol for approximately 6 weeks. RESULTS: Overall, 4819 patients were treated; baseline and Week 6 CCQ scores were available for 4700 patients, mostly classified as Global Initiative for Chronic Obstructive Lung Disease (GOLD) B (51.6%) or D (42.7%). After 6 weeks' treatment, 81.4% (95% confidence interval [95% CI] 80.24-82.49) of patients achieved therapeutic success; mean improvement in overall CCQ score was 1.02 points (95% CI 1.00-1.05). Improved CCQ score was seen in 92.2% of patients (95% CI 91.43-92.98), 2.5% had no change and 5.3% showed a worsening. When stratified by prior treatment, the greatest benefit was seen in treatment-naïve patients, with 85.7% achieving therapeutic success, compared with 79.5% of those pretreated with long-acting ß2-agonist (LABA)/inhaled corticosteroid (ICS) and 74.2% of those pretreated with LABA or long-acting muscarinic antagonist (LAMA) monotherapy. Overall, rescue medication decreased by 1.25 puffs/day (95% CI 1.19-1.31) versus baseline. In total, 29 patients (0.6%) reported drug-related adverse events and 7 patients reported serious adverse events (0.15%). CONCLUSION: In 4700 COPD patients, 6 weeks' treatment with tiotropium/olodaterol, as initial treatment or follow-up to LAMA or LABA monotherapy or LABA/ICS, improved CCQ and decreased rescue medication use. The adverse event profile was consistent with the known safety profile of tiotropium/olodaterol.

Varna Bay (Bulgaria): research based on the water-related challenges.

Many factors influence bay waters, including greater concentration of people in cities, industrial production, how land is used, dynamics of flow in water systems, and climate change. Water management remains one of the greatest human challenges. Scientists continue to respond to water-related challenges through the research to improve both human and environmental health. Study in the Varna Bay, providing key knowledge on hydrological and hydrochemical characteristics, was done over 2015-2018. Unified methods for marine waters were used. An increase in SST was ascertained. The range of SSS monthly fluctuations increased almost twice compared to a long-term range. Nitrate nitrogen range was bigger than phosphate phosphorus range. A sharp increase in organic matter was ascertained but generally the range decreased compared to a long-term range.

The snowdrop, wellspring of galanthamine : A brief descriptive and scientific history.

A history of the common snowdrop, Galanthus nivalis, is set out in folkloric fashion. Its religious connection is evident as well as the inspiration it arouses in artists and in ordinary persons. It is intended to shed light on the initial works relating to the snowdrop's alkaloid, galanthamine, performed by Soviet and Bulgarian scientists, which lie buried away and generally remain unknown. A brief history and nature of alkaloids continues with the emphasis placed on galanthamine. Heretofore hidden uses of snowdrops in traditional (folk) medicine are unveiled. An anticholinesterase with central and peripheral activity, feasible clinical indications with galanthamine are described. Certain disorders for which galanthamine has been deemed beneficial are presented for their historical value. Ongoing research regarding drugs and chemicals developed from the snowdrop and galanthamine is mentioned.

Daily supplementation with the Lab4P probiotic consortium induces significant weight loss in overweight adults.

This 9-month randomised, parallel, double-blind, single-centre, placebo-controlled study (PROBE, ISRCTN18030882) assessed the impact of probiotic supplementation on bodyweight. Seventy overweight Bulgarian participants aged 45-65 years with BMI 25-29.9 kg/m2 received a daily dose of the Lab4P probiotic comprising lactobacilli and bifidobacteria (50 billion cfu/day). Participants maintained their normal diet and lifestyle over the duration of the study. The primary outcome was change from baseline in body weight and secondary outcomes included changes in waist circumference, hip circumference and blood pressure. A significant between group decrease in body weight (3.16 kg, 95% CI 3.94, 2.38, p < 0.0001) was detected favouring the probiotic group. Supplementation also resulted in significant between group decreases in waist circumference (2.58 cm, 95% CI 3.23, 1.94, p < 0.0001) and hip circumference (2.66 cm, 95% CI 3.28, 2.05, p < 0.0001) but no changes in blood pressure were observed. These findings support the outcomes of a previous shorter-term Lab4P intervention study in overweight and obese participants (PROMAGEN, ISRCTN12562026). We conclude that Lab4P has consistent weight modulation capability in free-living overweight adults.

Trace elements in commonly used medicinal plants from Varna region, Bulgaria.

In this study, we assessed the concentrations of some trace and toxic elements (Cd, Pb, Zn, Cu, Ni, Cr, Fe, and Mn) in traditionally used wild medicinal plants: chamomile (Matricaria chamomilla), white yarrow (Achillea millefolium), linden (Tilia sp.), and elder (Sambucus nigra L.) collected from urban and rural region near Varna, Bulgaria. Concentrations of examined elements were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES) after sample mineralization. The samples were digested with concentrated nitric acid in a microwave system. Mean element levels in medicinal herbs were established in decreasing order as follows: Fe > Mn > Zn ≈ Cu > Pb > Ni > Cr > Cd. The content of toxic elements in medicinal herbs was found significantly higher in areas with intensive traffic compared with a suburban area. Instead discrimination between metal content in rural and urban samples was confirmed by PCA. Concentrations of toxic elements Cd and Pb in all plant species from the rural region were found in the range from not detected to 0.08 and 0.796 ng/kg, respectively and were below the permissible limit of the WHO.

Multivariate assessment of atmospheric deposition studies in Bulgaria based on moss biomonitors: trends between the 2005/2006 and 2015/2016 surveys.

This study aims to investigate the changes in atmospheric deposition trends in Bulgaria, studied using the moss biomonitoring technique since 1995. For the first time, a paired (site-wise) comparison was performed after a critical review of the sampling networks and adjusting for location, the distance between the sampling points, and moss species. Data from the 2005/2006 and 2015/2016 moss surveys were chosen as instrumental neutron activation analysis was employed in both to determine the content of 34 elements (Al, As, Ba, Br, Са, Ce, Cl, Со, Cr, Cs, Fe, Hf, I, K, La, Mn, Na, Nd, Ni, Rb, Sb, Sc, Se, Sr, Ta, Tb, Th, Ti, Tm, U, V, W, Yb, Zn). In addition, Cd, Cu, and Pb were determined using complementary analytical methods: inductively coupled plasma atomic emission spectroscopy in 2015/2016 and atomic absorption spectroscopy in 2005/2006. For the subset of 57 routinely sampled locations in Bulgaria, hierarchical clustering on principal components and multiple factor analysis (MFA) were applied to assess the spatial trends in the 10 years elapsed between the surveys, as well as to characterise the origin of the determined elements. Elevation and distance between the sampling points were used as additional variables in the multiple factor analysis plane to ascertain their effect on the overall variance in the datasets. Distribution maps were constructed to illustrate the deposition patterns for the pollutant Pb. The results were consistent with decreased industrial output in the country, increased coal combustion and transport pollution, and construction of roads.

Metabolite profiling by means of GC-MS combined with principal component analyses of natural populations of Nectaroscordum siculum ssp. bulgaricum (Janka) Stearn.

Nectaroscordum siculum ssp. bulgaricum (Janka) Stearn (Allium siculum subsp. dioscoridis (Sm.) K. Richt.) is a traditional culinary spice from South-East Europe. Studies of N. siculum have focused mainly on the botanical and taxonomic characteristics of this species and there is no data available in the scientific literature about its metabolite profile. Thus, the aim of the current study was metabolite profiling of four wild populations of N. siculum grown in Bulgaria by gas chromatography coupled to mass spectrometry (GC-MS) and subsequent principal component analysis (PCA) of the data obtained. The identified primary metabolites (carbohydrates, amino acids, organic acids and lipids) are initial compounds for the biosynthesis of different plant secondary metabolites, such as polyphenols and flavour compounds with valuable biological activities for humans. The health benefits of the phenolic acids identified in this study have been a prerequisite for the implementation of N. siculum in different food systems in order to increase their quality and biological value.

Genetic diversity, reproductive capacity and alkaloids content in three endemic Alkanna species.

The Balkans endemic species Alkanna primuliflora Griseb., A. stribrnyi Velen., and A. graeca Boiss. & Spruner have limited distribution in the Balkan Peninsula and a large variation in the morphological characteristics. The populations of the three Alkanna species in the Bulgarian flora are small and fragmented. There are no previous reports on the chemical profile or on the embryology of these species. The hypothesis was that the limited distribution of A. primuliflora, A. stribrnyi, and A. graeca was due to their reproductive capacity and genetic diversity. Furthermore, we hypothesized that the three species will contain pyrrolizidine alkaloids (PAs), as other species of the genus Alkanna (Boraginaceae), but they would have differential alkaloids composition. The population genetic structure and differentiation showed a clear distinction between species and revealed average levels of genetic diversity among the natural populations of the three Alkanna species. The embryological investigation observed stability of the processes in the male and female generative spheres and high viability of mature pollen and embryo of the three species. The normal formation of male and female gametophytes without deviations or degenerative processes, and observed levels of genetic diversity between Alkanna individuals are important in maintaining the size and resilience of the Alkanna populations. Eight alkaloids were identified by GC-MS in A. primuliflora and A. graeca and six alkaloids in A. stribrnyi. The main pyrrolizidine alkaloids (PAs) in all investigated species was triangularine. A. primuliflora and A. graeca showed similar chemical composition that comprised 9-angeloylretronecine, 7-tigloylretronecine, 9-tigloylretronecine, triangularicine, dihydroxytriangularine, dihydroxytriangularicine, whereas, in A. stribrnyi 9-tigloylretronecine, triangularicine and dihydroxytriangularicine were not found. This is the first report on the presence of PAs in A. primuliflora, A. stribrnyi and A. graeca. Besides, this is the first report on the embryology of these endemic species. The results contribute to the knowledge of the three endemic Alkanna species and will facilitate policy-making and defining new strategies for their conservation.

Initial Upper Palaeolithic Homo sapiens from Bacho Kiro Cave, Bulgaria.

The Middle to Upper Palaeolithic transition in Europe witnessed the replacement and partial absorption of local Neanderthal populations by Homo sapiens populations of African origin1. However, this process probably varied across regions and its details remain largely unknown. In particular, the duration of chronological overlap between the two groups is much debated, as are the implications of this overlap for the nature of the biological and cultural interactions between Neanderthals and H. sapiens. Here we report the discovery and direct dating of human remains found in association with Initial Upper Palaeolithic artefacts2, from excavations at Bacho Kiro Cave (Bulgaria). Morphological analysis of a tooth and mitochondrial DNA from several hominin bone fragments, identified through proteomic screening, assign these finds to H. sapiens and link the expansion of Initial Upper Palaeolithic technologies with the spread of H. sapiens into the mid-latitudes of Eurasia before 45 thousand years ago3. The excavations yielded a wealth of bone artefacts, including pendants manufactured from cave bear teeth that are reminiscent of those later produced by the last Neanderthals of western Europe4-6. These finds are consistent with models based on the arrival of multiple waves of H. sapiens into Europe coming into contact with declining Neanderthal populations7,8.