Synthesis, Antimicrobial Activities, and Molecular Modeling Studies of Agents for the Sortase A Enzyme.

Sortase A (SrtA) is an attractive target for developing new anti-infective drugs that aim to interfere with essential virulence mechanisms, such as adhesion to host cells and biofilm formation. Herein, twenty hydroxy, nitro, bromo, fluoro, and methoxy substituted chalcone compounds were synthesized, antimicrobial activities and molecular modeling strategies against the SrtA enzyme were investigated. The most active compounds were found to be T2, T4, and T19 against Streptococcus mutans (S. mutans) with MIC values of 1.93, 3.8, 3.94 µg/mL, and docking scores of -6.46, -6.63, -6.73 kcal/mol, respectively. Also, these three active compounds showed better activity than the chlorohexidine (CHX) (MIC value: 4.88 µg/mL, docking score: -6.29 kcal/mol) in both in vitro and in silico. Structural stability and binding free energy analysis of S.mutans SrtA with active compounds were measured by molecular dynamic (MD) simulations throughout 100 nanoseconds (ns) time. It was observed that the stability of the critical interactions between these compounds and the target enzyme was preserved. To prove further, in vivo biological evaluation studies could be conducted for the most promising precursor compounds T2, T4, and T19, and it might open new avenues to the discovery of more potent SrtA inhibitors.

Use of Dicranum polysetum extract against Paenibacillus larvae causing American Foulbrood under in vivo and in vitro conditions / Uso del extracto de Dicranum polysetum contra larvas de Paenibacillus causantes de la loque americana en condiciones in vivo e in vitro

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.(AU)

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.

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.

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.

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.

Dihydroisocoumarins and Phenylglycosides from Scorzonera longiana, Their Antimicrobial Activities and Molecular Docking Studies.

Five new phenyl dihydroisocoumarin glycosides (1-5) and two known compounds (6-7) were identified from the butanol fraction of Scorzonera longiana. The structures of 1-7 were elucidated based on spectroscopic methods. Antimicrobial, antitubercular, and antifungal evaluation of compounds 1-7 were carried out using the microdilution method against nine microorganisms. Compound 1 was active only against Mycobacterium smegmatis (Ms) with a MIC value of 14.84 µg/mL. All tested compounds (1-7) were active against Ms but only compounds 3-7 were active against fungi (C. albicans, S. cerevisiae) with MIC values of 25.0-125 µg/mL. In addition, molecular docking studies were conducted against Ms DprE1 (PDB ID: 4F4Q), Mycobacterium tuberculosis (Mbt) DprE1 (PDB ID: 6HEZ), and arabinosyltransferase C (EmbC, PDB ID: 7BVE) enzymes. Compounds 2, 5, and 7 are the most effective Ms 4F4Q inhibitors. Compound 4 was the most promising inhibitory activity on Mbt DprE with the lowest binding energy of -9,9 kcal/mol.

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.

Biological Activity and Phytochemical Analysis of Dicranum scoparium against the Bacterial Disease for Honey Bee.

Bacterial diseases, such as American Foulbrood (AFB) and European Foulbrood (EFB), are known to have catastrophic effects on honey bees (if left to spread, can wipe out entire colonies), leading to severe financial losses in the beekeeping industry. The aim of this study was to evaluate the pharmacological properties of methanol extract and its fractions (ethyl acetate, hexane, water) derived from Dicranum scoparium Hedw., which could be utilized as a potential drug to prevent the bacterial diseases (AFB and EFB) affecting the honey bees. For this purpose, crude methanol extract and ethyl acetate/hexane/water fractions were prepared from the aerial part of D. scoparium, collected from Trabzon province. Bio-guided fractionation of the extract and its fractions led to the first-time isolation of five compounds. The structure of all compounds was elucidated by nuclear magnetic resonance (NMR) spectroscopy, ultraviolet (UV) spectral analysis, Fourier-transform infrared spectroscopy (FT-IR), liquid chromatography quadrupole time-of-flight mass spectroscopy (LC-QToF-MS), and by comparison of their NMR data with that of literature. The analysis of these compounds revealed significant antibacterial and sporicidal activities against bacteria causing larval diseases in honey bees. The antibacterial activity of these compounds ranged from 0.6 to 60 µg/mL against AFB and EFB causing bacteria. Therefore, the natural raw extract and fractions of D. scoparium could be used as potential therapeutic agents against bacterial agents affecting honey bees.

Isolation, characterization, and comparative genomic analysis of vB_PlaM_Pd22F, a new bacteriophage of the family Myoviridae.

The use of phage and phage-based products for the prevention and treatment of bee disease is one of the promising natural alternatives to chemical or antibiotic treatments in beekeeping. A novel lysogenic bacteriophage, phage Pd22F (vB_PlaM_Pd22F), was isolated from Paenibacillus dendritiformis by the prophage induction method. This phage, which is capable of infecting Paenibacillus larvae and P. dendritiformis strains, was characterized by microbiological and comparative genomic analysis. Transmission electron microscopy images showed that phage Pd22F had the morphology of a myovirus. Whole-genome sequencing results showed that vB_Pla M_Pd22F has an 86,388-bp linear dsDNA genome with a GC content of 50.68%. This genome has 124 coding sequences (CDSs), 53% of which encode functionally unknown proteins and 57 of which encode proteins that show similarity to known proteins. In addition, one tRNA gene was found. The phage Pd22F genome does not contain any antimicrobial resistance genes. The similarity between the genome sequence of phage Pd22F and the whole genome sequences of other Paenibacillus phages available in the NCBI Virus Database was found to be below 50% (42%), indicating that phage Pd22F differs greatly from previously characterized phages at the DNA level. The results of comparative genomics and phylogenetic analysis revealed that Pd22F is a new phage belonging to the family Myoviridae, order Caudovirales. This is the first report of genomic and morphological characterization of a Paenibacillus dendritiformis prophage.

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.

Comparative evaluation of various herbal extracts on biofilms of Streptococcus mutans and Scardovia wiggsiae: An in vitro study.

BACKGROUND: Owing to their strong antimicrobial properties, Helichrysum arenarium (HA), Anzer thyme (AT), and Stevia rebaudiana (SR) have been commonly used in medicine. AIM: This study aimed to evaluate antimicrobial activities of HA, AT, and SR against S. mutans and S. wiggsiae in biofilms formed on primary teeth. DESIGN: Fifty enamel samples were divided into two groups: mono-species biofilm and two-species biofilm. Each biofilm group was divided into five subgroups (n = 5): group 1, HA; group 2, AT; group 3, SR; group 4, CHX (positive control); and group 5, distilled water (negative control). Minimum inhibitory concentration and minimum bactericidal concentration were determined. The number of viable microorganisms was counted. The presence of microorganisms was examined using a scanning electron microscope, and mineral analysis was performed using energy-dispersive X-ray analysis. RESULTS: In the mono-species biofilm, CHX was significantly more effective against S. mutans than other groups (p < .001). Furthermore, HA, AT, and SR groups showed significantly lower colony counts of S. mutans than distilled water (p < .05). In the two-species biofilm group, AT, SR, and CHX were significantly more effective against S. wiggsiae than distilled water (p < .05). CONCLUSIONS: HA, AT, and SR have been suggested as effective natural alternatives to CHX against cariogenic bacteria.

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, biological evaluation (antioxidant, antimicrobial, enzyme inhibition, and cytotoxic) and molecular docking study of hydroxy methoxy benzoin/benzil analogous.

In this work, due to the biological activity evaluation, a series of hydroxy methoxy benzoins (1-8), benzils (10-16) and methoxy benzoin/benzil-O-ß-d-glucosides (17-28) were synthesized. Antioxidant (FRAP, CUPRAC, DPPH), antimicrobial (16 microorganisms, and two yeast), enzyme inhibition (α-amylase, α-glucosidase, AChE, BChE, and tyrosinase) of all synthesized benzoin/benzil analogs were investigated. Benzoins (1-8) showed the most effective antioxidant properties compared to all three methods. Compound 28 against α-amylase, compound 9 against α-glucosidase, compound 11 against AChE, compound 2 against BChE, and compound 13 against tyrosinase showed the best activities with the better or similar IC50 values as used standards. Hydroxy methoxy benzoin compounds (1-8) among all four groups were seen as the most effective against the tested microorganism. Molecular docking analysis showed that all tested compounds 1-28 (0.01-2.22 µM) had the best binding affinity against AChE enzyme. Cytotoxic effects of the many of compounds (1-16, 21, and 24) also investigated and it was found that they caused different effects in different cells. The LDH tests of compounds 1a + b, 4, 7, 8, 9, 11, 12, 21, and 24, seemed to be effective compared to the positive control cisplatin. The cytotoxicity of compounds 6 (9.24%) for MCF7 cancer cells, 8 (5.16%) and 4 (8.26%) for HT29 cancer cells, 24 (9.84%) for Hep3B cells and 8 (8.52%), 7 (5.70%), 4 (6.94) and 9 (7.22%) for C6 cells were at normal values. And also cytotoxic activity of four compounds (5, 9, 21, and 24) among the all synthetic groups, were evaluated to the HeLa and RPE. Compound 5 showed anticancer activity on HeLa and RPE cancer cells as much as or better than cisplatin which was used as standard.

Synthesis of hydroxy benzoin/benzil analogs and investigation of their antioxidant, antimicrobial, enzyme inhibition, and cytotoxic activities.

In this study, hydroxy benzoin ( 1-7 ), benzil ( 8-14 ), and benzoin/benzil-O-ß-D-glucosides ( 15-25 ) were synthesized to investigate their biological activities. An efficient method for synthesizing hydroxy benzoin compounds ( 1 - 7 ) was prepared from four different benzaldehydes using an ultrasonic bath. Then, antioxidant (FRAP, CUPRAC, and DPPH), antimicrobial (3 Gram (-), 4/6 Gram (+), one tuberculosis and one fungus), and enzyme inhibition (acetylcholinesterase, butyrylcholine esterase, tyrosinase, α-amylase, and α- glucosidase) for the all synthesized compounds ( 1-25 ) were evaluated. And also, four most active compounds ( 4 , 12 , 18a+b , and 25 ) from each group were evaluated to the human cervical cancer cell line (HeLa) and anticancer screening tests against the human retinal normal cell line (RPE). Compound 4 showed HeLa and RPE cancer cell activities as much as cisplatin. The synthesized compounds were characterized by spectroscopic methods (NMR, FT-IR, UV, LC-QTOF-MS) and the ACD NMR program's help.

Determination of bioremediation properties of soil-borne Bacillus sp. 5O5Y11 and its effect on the development of Zea mays in the presence of copper.

Today, industrial activities lead to the accumulation of heavy metals in the soil, water, and air due to mine deposits and operations, fertilizers, and drugs used in agriculture, and urban wastes. Using microorganism bioremediation of metals is an important technique in solving these problems. Herein, a rhizoid bacterium isolated from orchids that grow in Ovit plateau was defined as Bacillus sp. 5O5Y11 by conventional and molecular methods and the bioremediation properties of strain were investigated. It was capable of growth at high salt (10-15%) concentration, wide temperature (10-45 °C) and pH range (pH 4.5-8.0), and was observed to have strong lecithinase, gelatinase activity, and nitrate reduction. When the plant growth-promoting properties of this strain were examined, strong siderophore and ammonium production were observed in in vitro conditions. Bacillus sp. 5O5Y11 was found to have high tolerance to a group of heavy metals [iron (Fe), copper (Cu), lead (Pb), silver (Ag), zinc (Zn)]. Minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) values of copper metal on Bacillus sp. 5O5Y11 were determined as 12.5 mM and 50 mM, respectively. The effectiveness of this bacterium on the germination and growth of maize plant in the presence and absence of copper were investigated. These results suggest that Bacillus sp. 5O5Y11 is a microorganism, which has potential in metal bioremediation and plant growth promotion.

Novel imidazo[2,1-b][1,3,4]thiadiazole (ITD) hybrid compounds: Design, synthesis, efficient antibacterial activity and antioxidant effects.

In this study, novel imidazo[2,1-b][1,3,4]thiadiazole (ITD) compounds were synthesized and their antimicrobial and antioxidant capacity was examined. The C-2 position of the ITD structure was fixed with the 3,4-hydroxybenzene ring and the properties of the two series of compounds obtained by phenyl or 4-chlorophenyl in the C-6 position were compared. In the formation of these series, new properties were determined by the addition of different pharmacophore to the target product by binding of the groups known in the literature from the C-5 position to the structure. In the study, it was seen that the compounds 4a, 4b, 5a, 5b, 7f, 10, 12 and 13 had very high anti-tuberculosis activities at low concentrations, 3b was found to exhibit moderate activity while other synthesis compounds exhibited moderate activity. In addition, it showed activity against gram positive and negative bacteria. In the determination of the antioxidant capacities of the newly synthesized compounds by FRAP and DPPH methods, the compounds showing activity were found to be 2, 3a, 3b, 6c, 9, 11 and 13. The structures of all synthesized compounds were solved by spectroscopic methods such as FT-IR, 1H NMR, 13C NMR and mass.

Design, synthesis and molecular modeling studies on novel moxifloxacin derivatives as potential antibacterial and antituberculosis agents.

Twenty-one novel alkyl/acyl/sulfonyl substituted fluoroquinolone derivatives were designed, synthesized and evaluated for their anti-tuberculosis and antibacterial activity. The targeted compounds were synthesized by the introduction of alkyl, acyl or sulfonyl moieties to the basic secondary amine moiety of moxifloxacin. Structures of the compounds were enlightened by FT-IR, 1H NMR, 13C NMR and HRMS data besides elemental analysis. Compounds were initially tested in vitro for their anti-mycobacterial activity against Mycobacterium tuberculosis H37Rv using microplate alamar blue assay. Minimal inhibitory concentration (MIC) values of all compounds were found between > 25.00-0.39 µg/mL while compounds 1, 2 and 13 revealed an outstanding activity against M. tuberculosis H37Rv with MIC values of 0.39 µg/mL. Activities of compounds 1-21 against to a number of Gram-positive and Gram-negative bacteria and fast growing mycobacterium strain were also investigated by agar well diffusion and microdilution methods. According to antimicrobial activity results, compound 13 was found the most potent derivative with a IC50 value of <1.23 µg/mL against Staphylococcus aureus and clinical strain of methicillin-resistant clinical strain of S. aureus.