Prevalence and molecular analysis of some important viruses in honey bee colonies in Türkiye: the status of multiple infections.

In this study, seven bee viruses of significant importance for bee health in Türkiye were investigated using one-step RT-PCR. For this purpose, larvae from 1183 hives and adult bees from 1196 hives were sampled from 400 apiaries in 40 provinces. The prevalence of viral infections in hives was as follows: acute bee paralysis virus (ABPV), 6.4%; black queen cell virus (BQCV), 77%; chronic bee paralysis virus (CBPV), 3.2%; deformed wing virus (DWV), 63.8%; Israel acute bee paralysis virus (IAPV), 7%; Kashmir bee virus (KBV), 2.7%; sacbrood virus (SBV), 49.7%. Moreover, 50 different combinations of viral infections were identified in the hives. While dual infections (36.1%) were the most common in hives, triple infections with BQCV, DWV, and SBV were found to have the highest prevalence (22.1%). At least one viral infection was detected in all of the apiaries tested. Phylogenetic analysis showed that the isolates from this study generally exhibited the highest similarity to previously reported Turkish isolates. When similarity ratios and the locations and types of amino acid mutations were analyzed, it was observed that the isolates from our study exhibited high similarity to isolates from various countries, including China, the United Kingdom, Syria, and Germany.

Use of Dicranum polysetum extract against Paenibacillus larvae causing American Foulbrood under in vivo and in vitro conditions.

Recent research shows that Dicranum species can be used to ameliorate the negative effects of honeybee bacterial diseases and that novel compounds isolated from these species may have the potential to treat bacterial diseases. This study aimed to investigate the efficacy of Dicranum polysetum Sw. against American Foulbrood using toxicity and larval model. The effectiveness of D. polysetum Sw. ethanol extract in combating AFB was investigated in vitro and in vivo. This study is important in finding an alternative treatment or prophylactic method to prevent American Foulbrood disease in honey bee colonies. Spore and vegetative forms of Paenibacillus larvae PB31B with ethanol extract of D. polysetum were tested on 2040 honey bee larvae under controlled conditions. Total phenolic and flavonoid contents of D. polysetum ethanol extracts were determined as 80.72 mg/GAE(Gallic acid equivalent) and 303.20 µg/mL, respectively. DPPH(2,2-diphenyl-1-picrylhydrazyl) radical scavenging percent inhibition value was calculated as 4.32%. In Spodoptera frugiperda (Sf9) and Lymantria dispar (LD652) cell lines, the cytotoxic activities of D. polysetum extract were below 20% at 50 µg/mL. The extract was shown to considerably decrease infection in the larvae, and the infection was clinically halted when the extract was administered during the first 24 h after spore contamination. The fact that the extract contains potent antimicrobial/antioxidant activity does not reduce larval viability and live weight, and does not interact with royal jelly is a promising development, particularly regarding its use to treat early-stage AFB infection.

PCR-based detection of the honeybee tracheal mite (Acarapis woodi) in Türkiye.

Acarapis woodi (Rennie 1921) (Acari: Tarsonemidae) is one of the mites that settles in the respiratory system of honeybees (Apis mellifera L. (Hymenoptera, Apidae)) and distributed throughout the world. It causes significant economic losses on honey production. In Türkiye, studies on the existence of A. woodi are very limited and so far, no studies on the molecular diagnosis and phylogenetic of it have been reported in Türkiye. This study was conducted to investigate the prevalence of A. woodi in Türkiye, especially in areas where beekeeping is intense. Diagnosis of A. woodi was performed using both microscopic and molecular methods using specific PCR primers. Adult honeybee samples were collected from 1.193 hives in 40 provinces of Türkiye between 2018 and 2019. Based on identification studies, the presence of A. woodi was detected in a total of 3 hives (0.5%) in 2018 and 4 hives (0.7%) in 2019. This is the first report for determination of A. woodi in Türkiye.

Honeybee-associated lactic acid bacteria and their probiotic potential for human use.

This study aims to identify lactic acid bacteria (LAB) isolated from honeybees (Apis mellifera workers and larvae) in detail and to determine their functional probiotic properties. A total of 11 strains were classified based on morphological and biochemical characteristics. Preliminary probiotic properties of strains, that were molecularly identified using 16 S rRNA, such as antimicrobial activity, tolerance to digestive conditions, aggregation ability, were investigated. The antimicrobial properties of strains were tested against a wide range of human pathogens. All strains that showed γ-hemolysis and did not contain bacteriophages were considered safe. The strains' survivability checked for 0.3% bile and 3.0-7.8 pH contents was promising. The highest autoaggregation ranged from 14.7 to 30.76% after 4 h. Tested LAB strains markedly exhibited coaggregation with Listeria monocytogenes and Escherichia coli. According to the results, tested bacteria showed significant antagonistic effects against pathogens, and positive probiotic characteristics compatible with in vitro gastrointestinal tract conditions. The results suggest that Apis mellifera LAB symbionts may have a probiotic potential, and be effective and safe candidates for human use. This study provides an addition to the development of the current knowledge by defining in detail honeybee-associated bacteria and determining their probiotic potential.

Biocidal properties of maltose reduced silver nanoparticles against American foulbrood diseases pathogens.

Bee disease caused by spore-forming Paenibacillus larvae and Paenibacillus alvei is a serious problem for honey production. Thus, there is an ongoing effort to find an effective agent that shows broad biocidal activity with minimal environmental hazard. In this study, the biocidal effect of maltose reduced silver nanoparticles (AgNPs) is evaluated against American foulbrood and European foulbrood pathogens. The results demonstrate that the maltose reduced AgNPs are excellent short and long-term biocides against P. larvae isolates. The long-term effect suggests that the Ag+ ions are released from the AgNPs with increasing time in a controlled manner.

Effect of propolis in gastric disorders: inhibition studies on the growth of Helicobacter pylori and production of its urease.

There is considerable interest in alternative approaches to inhibit Helicobacter pylori (H. pylori) and thus treat many stomach diseases. Propolis is a pharmaceutical mixture containing many natural bioactive substances. The aim of this study was to use propolis samples to treat H. pylori. The anti-H. pylori and anti-urease activities of 15 different ethanolic propolis extracts (EPEs) were tested. The total phenolic contents and total flavonoid contents of the EPE were also measured. The agar-well diffusion assay was carried out on H. pylori strain J99 and the inhibition zones were measured and compared with standards. All propolis extracts showed high inhibition of H. pylori J99, with inhibition diameters ranging from 31.0 to 47.0 mm. Helicobacter pylori urease inhibitory activity was measured using the phenol-hypochlorite assay; all EPEs showed significant inhibition against the enzyme, with inhibition concentrations (IC50; mg/mL) ranging from 0.260 to 1.525 mg/mL. The degree of inhibition was related to the phenolic content of the EPE. In conclusion, propolis extract was found to be a good inhibitor that can be used in H. pylori treatment to improve human health.

A comparative study of the antihyaluronidase, antiurease, antioxidant, antimicrobial and physicochemical properties of different unifloral degrees of chestnut (Castanea sativa Mill.) honeys.

This study was planned to investigate some physicochemical and anti-inflammatory, antioxidant, antimicrobial properties of three different degrees of unifloral characters of chestnut honeys. Antihyaluronidase, antiurease and antimicrobial activities were evaluated as anti-inflammatory characteristics. Total phenolic contents, flavonoids, tannins, phenolic profiles, ferric-reducing antioxidant power (FRAP), scavenging activities of 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS+) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals were evaluated as antioxidant properties. Color, optical rotation, conductivity, moisture, pH and ash content were evaluated as physicochemical parameters, and some sugars content, prolin, diastase, HMF and minerals (Na, K, Ca, P, Fe, Cu and Zn) were evaluated as chemical and biochemical parameters. All studied physicochemical and biological active properties were changed in line with the unifloral character of the chestnut honeys. A higher unifloral character was found associated with greater apitherapeutic capacity of the honey, as well as biological active compounds.

Prevalence and Phylogenetic Network Analysis of Nosema apis and Nosema ceranae Isolates from Honeybee Colonies in Türkiye.

PURPOSE: Nosemosis is a disease that infects both Western honeybees (Apis mellifera L.) and Asian honeybees (Apis cerana) and causes colony losses and low productivity worldwide. In order to control nosemosis, it is important to determine the distribution and prevalence of this disease agent in a particular region. For this purpose, a national study was conducted to assess the prevalence of Nosema ceranae and N. apis throughout Türkiye, to perform network analyses of the parasites, and to determine the presence of nosemosis. METHODS: In this study which aimed to assess the prevalence of N. apis and N. ceranae in different colony types and regions where beekeeping is intensive in Türkiye, specimens were collected from hives with no clinical signs. RESULTS: A total of 1194 Western honeybee colonies in 400 apiaries from 40 provinces of Türkiye were examined by microscopic and molecular techniques. Nosemosis was found in all of 40 provinces. The mean prevalence ratio was 64.3 ± 3.0, with 95% CI in apiaries and 40.5 ± 2.9, 95% CI in hives. Nosema ceranae DNA was detected in all of positive hives, while N. ceranae and N. apis co-infection was detected in only four colonies. CONCLUSION: This study showed that nosemosis has spread to all provinces, and it is common in every region of Türkiye. All of the N. ceranae or N. apis samples examined were 100% identical within themselves. Network analysis showed that they were within largest haplotype reported worldwide.

Design, synthesis and antimicrobial activities of some azole derivatives.

Three new 1,3,4-oxadiazole, 1,3-thiazolidine and 1,2,4-triazole derivatives were obtained starting from furan-2-carbohydrazide. Then, 1,2,4-triazole compound was converted to the corresponding Mannich bases using several secondary amines including piperidine, piperazine, morpholine or thiomorpholine moiety. The synthesis of 5-(furan-2-yl)-4-{[(4-methoxyphenyl)methylidene]amino}-4H-1,2,4-triazole-3-thiol (XIII) was performed starting from furan-2-carbohydrazide by three steps. The structures of the synthesized compounds were well characterized by elemental analyses, IR, 1H NMR, 13C NMR and mass spectral studies. Newly synthesized compounds were screened for their antimicrobial activities and some of them displayed activity against the tested microorganisms.

Comparing the biological properties and chemical profiling of chestnut bee pollen and bee bread collected from Anatolia.

Bee bread (BB) and bee pollen (BP) are accepted as functional food and considered in medical properties due to its important bioactive components. These bee products show different biological properties, but researches on these aspects have not been clear yet. In present study, Anatolian BB and BP extracts were analyzed for the first time for their pollen type, total phenolic (TPC) and flavonoid content (TFC), and antimicrobial and antioxidant properties. Samples were analyzed for their antimicrobial efficacy by the agar well diffusion and MIC methods. HPLC analysis was used to identify the compounds in the BB and BP samples. Antioxidant activity was measured by the FRAP and DPPH methods. As a result of microscopy for pollen identification, Fagaceae family was dominant. Phenolic compound analysis showed that the amounts of p-coumaric acid and rutin were found to be the highest in BB and BP, respectively. Stronger antioxidant activity was obtained from BP. MIC values of BB were range from 250 to 12.5 µg/mL. The most susceptible bacterium was Mycobacterium smegmatis. The extract of BP was effective on all gram-negative bacteria with doses range from 250 µg/mL to 500 µg/mL. The lowest MIC value was detected with the concentration of 12.5 µg/mL against M. smegmatis. Anatolian BB and BP could be considered as a functional foods due to antioxidant activity and may be beneficial in the management and treatment of pathogenic bacteria because of high antimicrobial activity.

Phytochemicals, antimicrobial, and sporicidal activities of moss, Dicranum polysetum Sw., against certain honey bee bacterial pathogens.

Beekeeping is an important agricultural and commercial activity globally practiced. Honey bee is attacked by certain infectious pathogens. Most important brood diseases are bacterial including American Foulbrood (AFB), caused by Paenibacillus larvae (P. larvae), and European Foulbrood (EFB) by Melissococcus plutonius (M. plutonius) in addition of secondary invaders, e.g. Paenibacillus alvei (P. alvei) and Paenibacillus dendritiformis (P. dendritiformis). These bacteria cause the death of larvae in honey bee colonies. In this work, antibacterial activities of extracts, fractions, and isolated certain compounds (nominated 1-3) all originated from moss, Dicranum polysetum Sw. ( D. polysetum), were tested against some honey bee bacterial pathogens. Minimum inhibitory concentration, minimum bactericidal concentration, and sporicidal values ​​of methanol extract, ethyl acetate, and n-hexane fractions ranged between 10.4 and 18.98, 83.4-303.75 & 5.86-18.98 µg/mL against P. larvae, respectively. Antimicrobial activities of the ethyl acetate sub-fractions (fraction) and the isolated compounds (1-3) were tested against AFB- and EFB-causing bacteria. Bio-guided chromatographic separation of ethyl acetate fraction, a crude methanolic extract obtained from aerial parts of D. polysetum resulted in three natural compounds: a novel one, i.e. glycer-2-yl hexadeca-4-yne-7Z,10Z,13Z-trienoate (1, dicrapolysetoate; given as trivial name), in addition to two known triterpenoids poriferasterol (2), and γ-taraxasterol (3). Minimum inhibitory concentration ranges were 1.4-60.75, 8.12-65.0, 2.09-33.44 & 1.8-28.75 µg/mL for sub-fractions, compounds 1, 2, and 3, respectively.

Chemical profiling and antimicrobial effect of Anatolian honey bee venom.

Due to increasing antibiotic resistance, there is an urgent need to find new antibiotic alternatives or supporters for the treatment of disease-causing pathogens. For this reason the aim of the study was examine the antimicrobial and antifungal activity of Anatolian (Anadolu) honey bee venom (HBV) against Gram-positive and Gram-negative bacteria and yeast-like fungi. At first step chemical analyses of HBV was performed by HPLC method. According to the results of HPLC analysis, we obtained a good separation of apamine, phospholipase A2 and melittin with the ratio of 1.83%, 20.60% and 57.62% respectively. The antimicrobial and antifungal activity of the Anatolian HBV was tested against 9 Gram (+), 7 Gram (-), 1 acid-alcohol-resistant and 3 yeast fungi. First, the activity of the Anatolian HBV sample against these microorganisms was determined by the agar well diffusion method, then their zones were measured. The microdilution method was used to determine the minimum inhibitory concentration (MIC) for the antimicrobial activity tests. The results of MIC values were varied from 3.06 µg/mL to 50 µg/mL for the tested microorganisms. It was found that Mycobacterium smegmatis and Streptococcus pyogenes were the most susceptible bacteria (3.06 µg/mL), followed by Vibrio sp., Aeromonas sobria, Enterococcus faecalis, Listeria monocytogenes, Staphylococcus aureus (MRSA) and B. subtilis with a MIC concentration of 6.125 µg/mL. These findings strongly suggest that Anatolian HBV will be developed as a new antibacterial-antifungal drug against Gram-positive, Gram negative and antibiotic-resistant bacteria and yeast-like fungi. However, further research is required to evaluate their in vivo efficacy and safe and effective delivery methods for their therapeutic use.

Evaluation of Stabilized Chlorine Dioxide in Terms of Antimicrobial Activity and Dentin Bond Strength.

BACKGROUND: Antimicrobial agents are recommended for disinfection of the cavity following mechanical dental caries removal prior to application of restorative material. There is limited information about stabilized Chlorine Dioxide (ClO2) as a cavity disinfectant. OBJECTIVES: The objective of this study is to determine the antimicrobial activity and effect on dentin bond strength of ClO2 compared to chlorhexidine digluconate (CHX), sodium hypochlorite (NaOCl) and Ethanolic Propolis Extract (EPE). METHODS: Antimicrobial activities of agents against oral pathogens (Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans, Lactobacillus acidophilus, Lactobacillus casei, Candida albicans, and Saccharomyces cerevisiae) and analyses of EPE were examined. Seventyfive mandibular third molars were sectioned, prepared and divided into five subgroups (n=15/group). Cavity disinfectants (2% CHX, 2.5% NaOCl, 30% EPE, 0.3% ClO2) were applied to etched dentin prior to adhesive and composite build-up. Shear bond strength (SBS) was evaluated with a universal testing machine at a crosshead speed of 0.5 mm/min. The SBS data were analyzed with One-way Analysis of Variance (ANOVA) and Tukey's post-hoc test (p <0.05). The failure modes were evaluated with a stereomicroscope. RESULTS: It was determined that the compared disinfectants were showed different inhibition zone values against oral pathogens. ClO2 exhibited the highest antimicrobial activity, followed by CHX, NaOCI and EPE, respectively. No statistically significant difference was observed in the SBS values between the disinfectant treated groups and control group. The failure modes were predominantly mixed. CONCLUSION: The use of 0.3% stabilized ClO2 as a cavity disinfectant agent exhibited high antimicrobial activity against oral pathogens and no adverse effects on SBS to etched dentin.

Antimicrobial and lipase inhibition of essential oil and solvent extracts of Cota tinctoria var. tinctoria and characterization of the essential oil.

The essential oil (EO) of Cota tinctoria var. tinctoria was analyzed using GC-FID / MS. A total of 51 compounds were determined from this taxon, accounting for 99.79% in hydrodistillation. Monoterpenes were the primary chemical class for the volatile organic compounds in the EO (36.1%, 13 compounds). Borneol (18.1%), camphor (14.9%), and ß-pinene (11.3%) were the major components in the EO of C. tinctoria var. tinctoria. The antimicrobial activities of EO and n-hexane, acetonitrile, methanol, and water solvent extracts of the taxon were screened in vitro against ten microorganisms. The EO yielded the best activity (15 mm, 372.5 MIC, 59600 µg/µL) against Mycobacterium smegmatis. The acetonitrile extract was the most active against the Staphylococcus aureus and Bacillus cereus with 274 µg/mL MIC value. IC50 values for the lipase enzyme inhibitory activity of EO and solvent extracts (n-hexane, acetonitrile, methanol, and water) were found to be 59.80 ± 4.3285 µg/mL 68.28 ± 3.1215 µg/mL, 52.60 ± 3.7526 µg/mL, 48.73 ± 2.8265 µg/mL, and 99.50 ± 5.5678 µg/mL, respectively.

Isolation, characterization, and comparative genomic analysis of vB_PlaP_SV21, new bacteriophage of Paenibacillus larvae.

Paenibacillus larvae cause an American foulbrood disease (AFB) that is responsible for the extinction of honeybee colonies and is a honeybee bacterial disease that has to be obligatory notified worldwide. Recently, bacteriophage studies targeting Paenibacillus larvae have emerged as a promising alternative treatment method. The inability of bacteria to create resistance against bacteriophages makes this method advantageous. As a consequence, this study was conducted to describe the genome and biological characteristics of a novel phage capable of lysing Paenibacillus larvae samples isolated from honeybee larva samples in Turkey. The Paenibacillus phage SV21 (vB_PlaP_SV21) was isolated by inducing Paenibacillus larvae strain SV21 with Mitomycin-C. Whole-genome sequencing, comparative genomics, and phylogenetic analysis of vB_PlaP_SV21 were performed. Transmission electron microscopy images showed that vB_PlaP_SV21 phage was a Podovirus morphology. The vB_PlaP_SV21 phage specific for Paenibacillus larvae was determined to belong to the Podoviridae family. Host range and specificity, burst size, lytic activity, and morphological characteristics of the phage were determined. Bioinformatic analysis of the Paenibacillus phage SV21 showed 77 coding sequences in its linear 44,949 bp dsDNA genome with a GC content of 39.33%. In this study, we analysed the genomes of all of the currently sequenced P. larvae phage genomes and classified them into five clusters and a singleton. According to molecular, morphological, and bioinformatics results, it was observed that API480 (podovirus), which was reported as a singleton in previous studies and public databases, and Paenibacillus phage SV21 phage could form a new cluster together.

Synthesis and antimicrobial activities of some new 1,2,3-triazole derivatives.

Some novel 4,5-disubstituted-2,4-dihydro-3H-1,2,4-triazol-3-one (3, 6, 8, 9) derivatives and or 3-(4-methylphenyl)[1,2,4]triazolo[3,4-b][1,3]benzoxazole (5) were synthesized from the reaction of various ester ethoxycarbonylhydrazones (1a-e) with several primary amines. The synthesis of 4-amino-5-(4-chlorophenyl)-2-[(5-mercapto-1,3,4-oxadiazol-2-yl)methyl]-2,4-dihydro-3H-1,2,4-triazol-3-one (13) was performed starting from 4-Amino-5-(4-chlorophenyl)-2,4-dihydro-3H-1,2,4-triazol-3-one (2) by four steps; then 13 was converted to the corresponding Schiff base (14) by using 4-methoxybenzaldehyde. Finally, two Mannich base derivatives of 14 were obtained by using morpholine or methyl piperazine as amine component. All newly synthesized compounds were screened for their antimicrobial activities and some of which were found to possess good or moderate activities against the test microorganisms.

Chemical composition, antimicrobial, and lipase enzyme activity of essential oil and solvent extracts from Serapias orientalis subsp. orientalis.

The volatile components of essential oil (EO), SPME, and SPME of solvent extracts ( n -hexane, methanol, and water) obtained from fresh Serapias orientalis subsp. orientalis ( Soo ) were analyzed by GC-FID/MS. EO of Soo gave 11 compounds in the percentage of 99.97%; capronaldehyde (37.01%), 2-( E )-hexenal (23.19%), and n -nonanal (19.05%) were found to be major constituents. SPME GC-FID/MS analyses of fresh plant and solvent extracts of Soo revealed 7, 12, 7, and 4 compounds within the range of 99.7% to 99.9%. Limonene (76.5%, 41.7%, and 61.3%) was the major compound in SPMEs of the n -hexane and methanol extracts. α -Methoxy- p -cresol (52.9%) was the main component in its water extract. The antimicrobial activity of EO and the solvent extracts of Soo were screened against 9microorganisms. EO showed the best activity against Mycobacterium smegmatis , with 79.5 µg/mL MIC value. The n -hexane, methanol, and water extracts were the most active against the Staphylococcus aureus within the range of 81.25-125.0 µg/mL (MIC). IC 50 values for the lipase enzyme inhibitory activity of EO and solvent extracts ( n -hexane, methanol, and water) were determined to be 59.87 µg/mL, 64.03 µg/mL, 101.91 µg/mL, and 121.24 µg/mL, respectively.

Microwave-assisted synthesis of 4'-azaflavones and their N-alkyl derivatives with biological activities.

4'-Azaflavone (=2-(pyridin-4-yl)-4H-1-benzopyran-4-one; 4) and 3-[(pyridin-4-yl)methyl]-4'-azaflavone (5) were synthesized by a simple environmentally friendly microwave-assisted one-pot method through the cyclization of 3-hydroxy-1-(2-hydroxyphenyl)-3-(pyridin-4-yl)propan-1-one (1), (E)-2'-hydroxy-4-azachalcone (2; chalcone=1,3-diphenylprop-2-en-1-one), and 2'-hydroxy-2-[(hydroxy)(pyridin-4-yl)methyl]-4''-azachalcone (3) under solventless conditions using silica-supported NaHSO(4), followed by treatment with base. In addition, N-alkyl-substituted 4'-azaflavonium bromides 6 and 7 were prepared from compounds 4 and 5, respectively. The antimicrobial and antioxidant activities of compounds 1-7 were tested. The N-alkyl-substituted 4'-azaflavonium bromides 6 and 7 showed high antimicrobial activity against the Gram-positive bacteria and the fungus tested, with MIC values close to those of reference antimicrobials ampicilline and fluconazole. The alkylated compounds 6 and 7 also showed a good antioxidant character in the two antioxidant methods, DPPH (=1,1-diphenyl-2-picrylhydrazyl) radical-scavenging and ferric reducing/antioxidant power (FRAP) tests.

Altitude Variation in the Composition of Essential Oils, Fatty Acid Methyl Esters, and Antimicrobial Activities of Two Subspecies of Primula vulgaris Grown in Turkey.

In this study, the changes caused by variation of altitude to the essential oils (EOs), fatty acid methyl esters (FAMEs), and antimicrobial activities of Primula vulgaris Huds. subsp. vulgaris (Pvv) and P. vulgaris Huds. subsp. sibthorpii (Hoffmanns) W.W.Sm. & Forrest (Pvs)) grown in Turkey were investigated. Major fluctuations in the composition of Pvv and Pvs oils included methyl-4-methoxy salicylate (4.5-35.3%; Pvv and 3.2-37.2%; Pvs), (Z,Z,Z)-7,10,13- hexadecatrienal (5.1-21.8%; Pvv and 4.4-15.2%; Pvs ) and flavone (5.5-14.9%; Pvv and 1.6-18.0%; Pvs). Fatty acid profile (C60-CI6o) changes were noted in .Pvv and Pvs. Methyl hexadecanoate (2.4-9.3%) and methyl octadecanoate (1.0-4.7%) were present in all the FAME samples of the plants. The antimicrobial activity of the EOs of Pvv and Pvs were tested against nine bacterial species, which showed activity against Mycobacterium smegmatis with minimum inhibitory concentrations (MIC) varying from 8.5 to 59.2 pg/mL in all samples, respectively, depending on the altitude at which the oils were obtained.

Synthesis and antimicrobial activities of some new 1-(5-phenylamino-[1,3,4]thiadiazol-2-yl)methyl-5-oxo-[1,2,4]triazole and 1-(4-phenyl-5-thioxo-[1,2,4]triazol-3-yl)methyl-5-oxo- [1,2,4]triazole derivatives.

Acetic acid ethyl esters containing 5-oxo-[1,2,4]triazole ring (2) were synthesized by the condensation of compounds 1a-f with ethyl bromoacetate in basic media. The reaction of compounds 2a-f with hydrazine hydrate led to the formation of acid hydrazides (3a-f). The treatment of compounds 3 with two divers aromatic aldehydes resulted in the formation of arylidene hydrazides as cis-trans conformers (4a,c,e,f, 5a,e,f). The thiosemicarbazide derivatives (6a,c,d,f) were afforded by the reaction of corresponding compounds 3 with phenylisothiocyanate. The treatment of compounds 6a,c,d,f with sulfuric acidic caused the conversion of side-chain of compounds 6a,c,d,f into 1,3,4-thiadiazol ring; thus, compounds 7a,c,d,f were obtained. On the other hand, the cyclization of compounds 6a,c,d,f in the presence of 2 N NaOH resulted in the formation of compounds 8a,c,d,f containing two [1,2,4]triazole rings which are linked to each other via a methylene bridge. Compounds 4a, f, 5a, 7a, d, f, 8a and d have shown antimicrobial activity against one or more microorganism, but no antifungal activity has been observed against yeast like fungi. Also inhibitory effect on mycelial growth by compounds 4e, 7d and 8f has been observed. Compounds 4c and 5f were found to possess antitumor active towards breast cancer.