Phytochemical Analysis and Antimicrobial Activity of Lawsonia inermis Leaf Extracts from Burkina Faso

Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious dermatoses. This study was carried out to evaluate the phytochemical profile of the crude ethanolic extract of the plant leaves and its fractions as well as their antimicrobial activities. The phytochemical profile was performed using high-performance thin-layer chromatography (HPTLC), gas chromatography-mass spectrometry (GC-MS), and high-performance liquid chromatography (HPLC). Additionally, the phenolic and flavonoid contents were determined using the Folin-Ciocalteu spectrophotometric and the aluminum trichloride methods. Antimicrobial activity was tested using disc diffusion and microdilution methods. The presence of flavonoids, tannins, sterols, and triterpenes was revealed. GC-MS detected twelve compounds main compounds consisting of saturated and unsaturated fatty acids and phenolic and terpenoid compounds among twenty-seven components. HPLC also detected high contents of phenolic acids and flavonoids. The most abundant triterpene and sterols were ursolic acid (around 43.14 g/100g DW, 13.9 g/100g dry weight (DW), and 0.68 g/100g DW) in the crude ethanolic extract of leaves (FeLi), hexane fraction (FHLi) and dichloromethane fraction (FDLi), respectively and, β-sitosterol in FeLi (56.7 mg/100g DW), FHLi (10.55 g/100g DW), FDLi (106.1 mg/100g DW) and butanol fraction (FBLi) (357.4 mg/100g DW). Among the flavonoids, rutin = 3.24 g/100g and quercetin = 0.63 g/100g in the ethanolic extract, rutin = 15.73 g/100g in the dichloromethane fraction, and rutin = 0.23 g/100g) in the aqueous fraction;and among phenolic compounds, caffeic acid (37.65 g/100g DW) and vanillic acid (22.70 g/100g DW) were the most important in the ethyl acetate fraction (FAeLi). All organic fractions exhibited interesting antibacterial and antifungal activities against the tested strains, with the best activity recorded with the dichloromethane and ethyl acetate fractions. The leaf extracts’ phytochemical profile and antimicrobial activity support the use of Lawsonia inermis against infectious skin diseases.

A pilot survey on antimicrobial activity and diversity of soil-derived actinobacteria from different depths in Gudzhirganskoe saline lake in Eastern Siberia

To explore pharmaceutical actinobacteria from salty environments in Siberia,8 soil samples were collected from different depths of Gudzhirganskoe saline lake,the Republic of Buryatia,Russia.Totally,635 actinobacterial strains affiliated with 21 genera in 12 families of 7 orders were obtained by culture-dependent approaches.The predominant genus was Streptomyces(74.5%),followed by Microbacterium(4.9%),Agromyces(3.5%),Nocardiopsis(3.0%),and Kitasatospora(2.5%).Seven strains showed relatively low 16 S rRNA similarities(<98.65%)with validly described species.Seventy-seven strains were selected as representatives to evaluate their antimicrobial activities and underlying mechanisms by paper-disk diffusion method and a double fluorescent protein reporter system(pDualrep 2),respectively.Streptomyces sp.S 6 b 3-1 was highlighted due to its strong inhibitory activities against Gram-positive bacteria and underlying antibacterial mechanism by inducing the SOS response in the reporter system.LG-1,(R)-6-[1-(benzoyloxy)ethyl]-phenazine-1-carboxylic acid,an analogue of saphenamycin was finally isolated from the culture broth of Streptomyces strain.This study preliminarily explored the actinobacterial diversity of soil samples collected in the highly alkaline and saline lake Gudzhirganskoe by culture-dependent approach and their capacity to produce antibiotics for the first time,which revealed that it deserves to make more efforts to discover new actinobacterial species and potential new antibiotics from the saline lake in Eastern Siberia.

Synthesis, Structural Characterization and Antimicrobial Activity of a Novel Cobalt(II) Complex Based on 3-Methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One

New cobalt(II) complex, [Co(O2C15H11N2S)2(OH2)2]∙2H2O (1∙2H2O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)2∙6H2O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H2O. Compound 1∙2H2O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H2O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H2O displayed moderate activity (10 ∙2H2O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus).

Design of pH-responsive antimicrobial peptide melittin analog-camptothecin conjugates for tumor therapy

Melittin,a classical antimicrobial peptide,is a highly potent antitumor agent.However,its significant toxicity seriously hampers its application in tumor therapy.In this study,we developed novel melittin analogs with pH-responsive,cell-penetrating and membranelytic activities by replacing arginine and lysine with histidine.After conjugation with camptothecin(CPT),CPT-AAM-1 and CPT-AAM-2 were capable of killing tumor cells by releasing CPT at low concentrations and disrupting cell membranes at high concentrations under acidic conditions.Notably,we found that the C-terminus of the melittin analogs was more suitable for drug conjugation than the N-terminus.CPT-AAM-1 significantly suppressed melanoma growth in vivo with relatively low toxicity.Collectively,the present study demonstrates that the development of antitumor drugs based on pH-responsive antimicrobial peptide-drug conjugates is a promising strategy.

Synthesis, Structural Characterization and Antimicrobial Activity of a Novel Cobalt(II) Complex Based on 3-Methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One

New cobalt(II) complex, [Co(O2C15H11N2S)2(OH2)2]∙2H2O (1∙2H2O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)2∙6H2O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H2O. Compound 1∙2H2O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H2O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H2O displayed moderate activity (10 ∙2H2O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus).

Antimicrobial and Antioxidant Activities of a Brown Wood Rotting Mushroom Piptoporellus baudonii from Benin (Tropical Africa)

Piptoporellus baudonii, previously known as Laetiporus baudonii, is an African species that was considered to be a sister species to Laetiporus sulphureus, another European species known for its medicinal value. While much is known about the edibility and antimicrobial properties of L. sulphureus, African species like P. baudonii remain understudied. This study investigated the antimicrobial and antioxidant properties of P. baudonii extracts (powder maceration) prepared using ethanol, methanol and water with fractions obtained via differential solubility in hexane, ethyl acetate and n-butanol. Before the antimicrobial analysis, the study material was accurately identified using both morphology and molecular techniques. Antimicrobial activity was tested against fungi, gram-positive, and gram-negative bacteria using a broth serial microdilution method, while antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Ferric Reducing Antioxidant Power FRAP methods. Phylogenetic analysis confirmed the specimen as P. baudonii, with genetic material from Benin grouping it with other P. baudonii from Tanzania and other unknown regions, forming a well-supported clade (100/100). The ethanol (1.71), methanol (2.41) extracts, along with ethyl acetate (1.36), n-butanol (1.18), and hexane (12.91) fractions showed significant antioxidant activity with EC50 values below 20 µg∙mL−1. The highest antimicrobial inhibition was seen in the n-butanol (58%) and ethyl acetate (54%) fractions, followed by ethanol (49%) and hexane (48%). Methanol exhibited the lowest inhibition (46.10%). These values were compared to the standard (Vitamin C). The examined extracts demonstrated high bactericidal properties, with an MBC/MIC ratio (R) of 1 to 4, particularly effective ethyl acetate against Escherichia coli (R = 2) and ethanol extract with strong activity against Enterococcus faecalis (R = 4). Further chemical and cytotoxicity studies are warranted to fully explore the pharmaceutical potential of P. baudonii.

Hydrolytic and Antimicrobial Activities of Bacteria Isolated from Fermented Peppers Sold in Markets at Brazzaville, Republic of the Congo

Microorganisms are omnipresent in all environments and play mainly the role of transformers, thanks to the multiple enzymes they are able to produce. In order to valorize fermented foods in the Republic of the Congo, this work aimed to characterize and study some properties of microorganisms isolated from samples of peppers sold in three markets of Brazzaville. A numeration of the total aerobic mesophilic flora (TAMF) was made in a solid medium, allowing the evaluation of each sample’s microbial concentration. The microbial mass varied from 2.8 × 105 CFU/g for the Ouénzé sample to 1.8 × 104 CFU/g for the Total sample and 2 × 104 CFU/g for the Moungali market sample. The evaluation of the enzymatic properties of the Bacillus isolates showed that 68.42% were capable of producing cellulases and 78.94% were capable of producing amylases and proteases. Antimicrobial activities revealed that 63.15% of the isolates were able to secrete inhibitory substances against E. coli and Staphylococcus aureus. Molecular analysis by PCR amplification, sequencing of the 16S rRNA gene and BLAST bioinformatics analysis provides newly identified bacteria strains with new accession numbers in GenBank: Bacillus thuringiensis MBCBR322 (OP474008), Bacillus megaterium MBCBJ1822 (OP476493), Bacillus thuringiensis MBCBR222 (OP476494), Priestia megaterium MBCBJ2022 (OP476495) and Lactobacillus paraplantarum MBCBR1522 (OP476496). Multiple sequences alignment of identified sequences with their homologs of GenBank has shown high similarities. The phylogenetic inference assay has provided the two groups of strains observed in this study, and the two groups are very coherent with the phylogeny of the reference.

Ultrasonic-Assisted Extraction of Fucoxanthin from Marine Macroalga Padina australis:Optimization,Bioactivity,and Structural Characterization

Macroalgae serve as a potential feedstock for fucoxanthin extraction.Fucoxanthin,a bioactive pigment found in the chloroplasts of marine algae,exhibits significant pharmacological properties.As a member of the carotenoid family,fucoxanthin plays a crucial role in both the food and pharmaceutical industries.This research explores the effects of ultrasonics on the extraction of fucoxanthin from the marine macroalga Padina australis.In addition,various extraction techniques and the influence of solvents on the efficient separation of fucoxanthin from algae have been studied and compared.Using methanol,chloroform,and a combination of methanol and chloroform(1:1,v/v),conventional fucoxanthin extraction from Padina australis yielded 8.12 mg of fucoxanthin per gram of biomass.However,the ultrasonic-assisted extraction resulted in a significantly higher yield of 16.9 mg of fucoxanthin per gram of biomass,demonstrating that the use of ultrasonics enhances the extraction rate compared to conventional methods.Therefore,the efficient separation of fucoxanthin from Padina australis is highly dependent on ultrasonic-assisted extraction.The process conditions for the extraction were optimized to maximize the yield of fucoxanthin from seaweeds.The following parameters were selected for optimization studies:moisture content,particle size,mixing speed,extraction temperature,extraction duration,and solid-to-solvent ratio.The extracted fucoxanthin exhibited various biological activities,including antimicrobial and antioxidant properties,and its structure was elucidated through FTIR and NMR spectroscopy.Additionally,thin-layer chromatography of the crude algae extracts confirmed the presence of fucoxanthin in the marine algae.Given these findings,the optimized extraction process holds the potential for scaling up to large-scale fucoxanthin production.Fucoxanthin,as a potent pharmacological agent,offers promising applications in the treatment of various ailments.

Biosynthesis of Copper Nanoparticles using an Extract of the root of Asparagus racemosus:Basic Synthesis,Antimicrobial,and Anti-oxidant Potentials

Copper nanoparticles(CuNPs)have emerged as a promising alternative due to their unique antimicrobial properties.The synthesis of CuNPs using Asparagus racemosus,commonly known as Shatavari,offers a sustainable and environmentally friendly approach to producing nanomaterials.Moreover,the resulting CuNPs have been found to possess excellent antibacterial,and antioxidant properties,which further expands their potential applications in medicine and environmental remediation.In this article,we discussed the in vitro characterization of the CuNPs.In vitro studies revealed that CuNPs have the potential for biomedical applications and as a base nanomaterial for the construction of drug delivery and targeting vehicles.

Biosynthesis of Silver Nanoparticles with Clerodendron phlomoides Leave Extract:Particle Morphology,Antimicrobial Potential and Application

Silver nanoparticles are versatile nanomaterials that have found numerous applications in various fields.The use of plant extract for the synthesis of silver is a green and sustainable approach.Clerodendron phlomoides leaves extract has been found to contain various phytochemicals,such as phenols,flavonoids,tannins,and alkaloids,which possess reducing and stabilizing properties that can aid the production of silver particles.In this paper,morphological and topographical analyses were performed on silver nanoparticles.The biosynthesized silver nanoparticles showed antimicrobial potential against wound pathogens.SEM and TEM micrographs revealed that the particles were sphere and nanosized,which makes them suitable for various biomedical applications.

Analysis of the Antimicrobial Activity of Antimicrobial Peptides Extracted from Immunized Tenebrio molitor Induced by Different Microbial Treatments Against 26 Pathogens

[Objective] The study was to explore whether antimicrobial activity of the antimicrobial peptides extracted from immunized Tenebrio molitor varied with different pathogens as inducers.[Method]By inducing T.molitor hungry larvaes to generate immune response via feeding with bacteria and with fungi or actinomycete post to pricking,the antimicrobial peptides extracts were obtained by grinding and centrifuging the cultures.Its antimicrobial activity against 26 pathogens was measured by bacteriostatic ring,and evaluated by trisection to four types and inhibitory spectrum.[Result]Both the antimicrobial activity and antimicrobial spectrum of the antimicrobial peptides extracts varied remarkably among different pathogens as inducers.[Conclusion]Bio-control used strains have obvious advantage in inducing the insect to express body fluid immunity material-antimicrobial peptides.

Composition and antimicrobial activity of Cistus munbyi essential oil: an endemic plant from Algeria

The chemical composition and antimicrobial potential of Cistus munbyi essential oil were studied for the first time. GC and GC–MS analysis revealed 48 compounds representing 96.98% of the oil. Terpinen-4-ol(23.75%), meta-Cymene(17.30%), and Sabinene(12.38%)were the major constituents. Antimicrobial activity was evaluated against nine pathogens using the disc diffusion and broth micro-dilution methods. Results show that C.munbyi essential oil possesses strong antimicrobial activity against all strains, regardless if Gram-positive or Gramnegative bacteria, or yeast, with MICs values not exceeding10(mg/ml). In addition to its efficacy, C. munbyi essential oil has an unusual antimicrobial potency which is attributed to its specific chemical composition. Thus, findings presented here suggest that endemic C. munbyi contains a very interesting essential oil that may be valuable in several areas.

Beeswax:A minireview of its antimicrobial activity and its application in medicine

Beeswax is the substance that forms the structure of a honeycomb; the bees secrete wax to build the honeycombs where to store honey.Thanks to its rich hydrophobic protective properties,the beeswax is in fact present within cosmetics and body products.Also,beeswax is used in the food industry:as a film to wrap cheese for maturing or as a food additive(E901) to give shine to the products.Exactly as the honey which it contains,beeswax is also characterized by several therapeutic properties of great interest to us; it is thought to be particularly effective in healing bruises,inflammation and burns.Recently,the interest of researchers has moved even on antimicrobial properties of beeswax although there are still few studies in the literature focused only on the action of beeswax.The few studies showed an anitimicrobic effectiveness of beeswax against overall Staphylococcus aureus,Salmonella enterica,Candida albicans and Aspergillus niger; these inhibitory effects are enhanced synergistically with other natural products such as honey or olive oil.This minireview aims to be a collection of major scientific works that have considered the antimicrobial activity of beeswax alone or in combination with other natural products in recent years.

DCC/DMAP mediated esterification of hydroxy and non-hydroxy olefinic fatty acids with β-sitosterol:In vitro antimicrobial activity

A new series of fatty alkenoates were synthesized using an appropriate synthetic route involving DCC and DMAP as catalysts. Compounds were characterized by their spectral data.All the synthesized compounds were evaluated for their in vitro antimicrobial activity.The minimum inhibitory concentration(MIC),minimum bacterial concentration(MBC) and minimum fungicidal concentration(MFC) were determined for test compounds as well as for reference standards.Among the compounds tested, compounds having hydroxy group at the fatty acid chain showed the most potent antibacterial as well as antifungal activities.

Inhibition of α/β-K_6P_2W_(18)O_(62)·10H_2O on the Activity of Mushroom Tyrosinase and Its Antimicrobial Effects

Dawson-type phosphotungstic polyoxometalate α/β-K6P2W18O62·10H2O（P2W18） was synthesized and its inhibitory effect on the mushroom tyrosinase was investigated. It could inhibit diphenolase activity of mushroom tyrosinase as an irreversible inhibitor. When the concentration of the enzyme reached 0.0176 mg/mL, the concentration of P2W18 leading to 50% activity lost（IC50） was 0.05 mmol/L for monophenolase and 0.64 mmol/L for diphenolase. In addition, the antimicrobial activity of P2W18 was evaluated by zone of inhibition test. The results show that P2W18 possesses effective antimicrobial ability against Escherichia coli, Bacillus subtilis, yeast, especially Escherichia coli and yeast.

Antimicrobial activity of cotton and silk fabric with herbal extract by micro encapsulation

Objective:To explore the antimicrobial activity of microcapsules encapsulated with mixture of herbs like neem,tulsi and turmeric,and its application on cellulosic fabric in the form of microcapsules.Methods:The microcapsules were prepared from the mixture of herbs by plain diffusion method,a natural encapsulation technique with yeast and applied on cotton and silk fabric by pad-dry-cure method.The microcapsules were fixed on cotton and silk fabric using the binder UF Silpure FBR-5(PA)B at 120℃.The antimicrobial activities of the finished fabric were assessed by using three types of bacteria including Staphylococcus aureus,Escherichia coli and Pseudomonas.Results:The results of antimicrobial activity from the tests including parallel streak method and disc diffusion method showed that activity of the mixture of herbs was very effective among the three types of bacteria selected,and the antimicrobial activity of prepared microcapsule against Pseudomonas was very good.Conclusions:The herbal microcapsule treated fabric could be applied in the field of medicine.The scanning electron microscope photographs ensure the fixing of the microcapsules firmly in the yarn structure of plain woven cotton and silk fabric.

Antimicrobial peptides: mechanism of action, activity and clinical potential

The management of bacterial infections is becoming a major clinical challenge due to the rapid evolution of antibiotic resistant bacteria.As an excellent candidate to overcome antibiotic resistance,antimicrobial peptides(AMPs)that are produced from the synthetic and natural sources demonstrate a broad-spectrum antimicrobial activity with the high specificity and low toxicity.These peptides possess distinctive structures and functions by employing sophisticated mechanisms of action.This comprehensive review provides a broad overview of AMPs from the origin,structural characteristics,mechanisms of action,biological activities to clinical applications.We finally discuss the strategies to optimize and develop AMP-based treatment as the potential antimicrobial and anticancer therapeutics.

Antimicrobial Activity of Submerged Culture Extracts from Xylaria striata

[ Objective ] The paper was to explore the antimicmbial activities of extracts from Xylaria striata via submerged culture. [ Methods ] The antibacterial activities of X. striata extracts against 10 kinds of bacteria were determined using Oxford cup method and mJcroplate assay, and the antifungal activities against nine kinds of pathogenic fungi were determined using mycelial growth rate method. [ Results ] The inhibition zone diameters of the mycelium extract against tested bacte- ria ranged from 13.0 to 17.5 mm, and that of the fermentation broth extract ranged from 10.5 to 12.7 ram. Enterobacter cloacae was the most sensitive to both my- celium extract and fermentation broth extract, with the inhibition zone diameters of 17.1 and 12.7 mm and the minimum inhibitory concentrations of 2.5 and 5 mg/mL, respectively. The inhibitory effects of the mycelium extract and the fermentation broth extract against Fusarium graminearum were the greatest, and the in- hibition rates were 89.88% and 69.53%, respectively. [ Conclusion] X. striata has potential antimicrobial activity and deserves to be further studied.

Studies on the Antimicrobial Activity of Chitooligosaccharides from Housefly Larvae, Musca domestica vicina Macquart(Diptera: Muscidae)

The inhibition effect of chitooligosaccharides from housefly larvae on pathogens ofcrops seeds, fruits or vegetables was studied and the main factors influencing theantimicrobial activity of chitooligosaccharides were also investigated. It was foundthat chitooligosaccharides from housefly larvae had wide spectrum fungistasis. It canstrongly inhibit the development of 31 kinds of plant pathogenic fungi such as corticiumrolfsii Saccardo. The results indicated that the degree of deacelylation (DD) or theaverage molecular weight(MW)of chitooligosaccharides were related to the antimicrobialactivity. The antimicrobial activity increased with the rising of DD or the declining ofMW. Pot culture results showed that chitooligosaccharide could enhance the rate ofgermination and emergence of the seeds of maize, wheat and cotton. Chitooligosaccharidehad certain effect on corn southern leaf blight caused by Helminthosporium maydis.

Hybrid Antimicrobial Peptide Buforin Ⅱ-Cecropin B Exhibits Antimicrobial Activity

[ Objective ] This study aimed to investigate the antimicrobial activity of hybrid antimicrobial peptide buforin II-cecropin B. [ Method ] Gene fragment BC encoding the hybrid antimicrobial peptide Buforin II-Cecropin B was synthesized by SOE-PCR with six primers designed according to the published amino acid sequences. Then, the BC gene fragment was ligated into pET32a vector and expressed in BI21. Antimierobial ability of the crude hybrid antimicrobial peptide was detected with the Oxford cup method. [ Result] The BC gene fragment was correctly amplified by SOE-PCR and ligated into pET32a vector, to construct the expression vector pET32-BC. The hybrid antimicrobial peptide buforin II-cecropin B was expressed in BI21 after induction by IPTG. The optimal induction time was 2 h. Antimicrobial activity assay suggested that the hybrid antimicrobial peptide possessed antimicrobial activity to Escherichia coli and Bacillus subtilis. [ Conclusion] The hybrid antimicrobial peptide buforin II-cecropin B exhibited antimicrobial activity to Gram-negative E. coli and Gram-positive B. subtilis strains.