Screening and antibacterial efficacy of selected Indian medicinal plants

Sprayable, thermosensitive hydrogels for promoting wound healing based on hollow, porous and pH-sensitive ZnO microspheres

A solvothermal method and the subsequent heat treatment process were developed to fabricate hollow ZnO particles with hierarchical pores on a large scale. The as-obtained hollow, porous ZnO microspheres with tunable sizes, high specific surface areas, pH sensitivity, antibacterial properties, and high adsorption capacities showed significant advantages for drug delivery. Sprayable hydrogels containing hollow, porous ZnO microspheres and curcumin nanoparticles (CNPs) were prepared to accelerate wound healing. The water-dispersed CNPs promoted both the migration of fibroblasts and angiogenesis and an aqueous solution of Pluronic F127 (a temperature-sensitive phase-change hydrogel material) was shown to be an effective choice for medical dressings. The experimental data suggest that hollow, porous ZnO microspheres can be loaded with additional CNPs to achieve continuous long-term therapeutic effects.

Ethnomedicinal Usage, Phytochemistry and Pharmacological Potential of Solanum surattense Burm. f

Solanum surattense Burm. f. is a significant member of the Solanaceae family, and the Solanum genus is renowned for its traditional medicinal uses and bioactive potential. This systematic review adheres to PRISMA methodology, analyzing scientific publications between 1753 and 2023 from B-on, Google Scholar, PubMed, Science Direct, and Web of Science, aiming to provide comprehensive and updated information on the distribution, ethnomedicinal uses, chemical constituents, and pharmacological activities of S. surattense, highlighting its potential as a source of herbal drugs. Ethnomedicinally, this species is important to treat skin diseases, piles complications, and toothache. The fruit was found to be the most used part of this plant (25%), together with the whole plant (22%) used to treat different ailments, and its decoction was found to be the most preferable mode of herbal drug preparation. A total of 338 metabolites of various chemical classes were isolated from S. surattense, including 137 (40.53%) terpenoids, 56 (16.56%) phenol derivatives, and 52 (15.38%) lipids. Mixtures of different parts of this plant in water-ethanol have shown in vitro and/or in vivo antioxidant, anti-inflammatory, antimicrobial, anti-tumoral, hepatoprotective, and larvicidal activities. Among the metabolites, 51 were identified and biologically tested, presenting antioxidant, anti-inflammatory, and antitumoral as the most reported activities. Clinical trials in humans made with the whole plant extract showed its efficacy as an anti-asthmatic agent. Mostly steroidal alkaloids and triterpenoids, such as solamargine, solanidine, solasodine, solasonine, tomatidine, xanthosaponin A-B, dioscin, lupeol, and stigmasterol are biologically the most active metabolites with high potency that reflects the new and high potential of this species as a novel source of herbal medicines. More experimental studies and a deeper understanding of this plant must be conducted to ensure its use as a source of raw materials for pharmaceutical use.

Potential of Selected African Medicinal Plants as Alternative Therapeutics against Multi-Drug-Resistant Bacteria

Antimicrobial resistance is considered a "One-Health" problem, impacting humans, animals, and the environment. The problem of the rapid development and spread of bacteria resistant to multiple antibiotics is a rising global health threat affecting both rich and poor nations. Low- and middle-income countries are at highest risk, in part due to the lack of innovative research on the surveillance and discovery of novel therapeutic options. Fast and effective drug discovery is crucial towards combatting antimicrobial resistance and reducing the burden of infectious diseases. African medicinal plants have been used for millennia in folk medicine to cure many diseases and ailments. Over 10% of the Southern African vegetation is applied in traditional medicine, with over 15 species being partially or fully commercialized. These include the genera Euclea, Ficus, Aloe, Lippia. And Artemisia, amongst many others. Bioactive compounds from indigenous medicinal plants, alone or in combination with existing antimicrobials, offer promising solutions towards overcoming multi-drug resistance. Secondary metabolites have different mechanisms and modes of action against bacteria, such as the inhibition and disruption of cell wall synthesis; inhibition of DNA replication and ATP synthesis; inhibition of quorum sensing; inhibition of AHL or oligopeptide signal generation, broadcasting, and reception; inhibition of the formation of biofilm; disruption of pathogenicity activities; and generation of reactive oxygen species. The aim of this review is to highlight some promising traditional medicinal plants found in Africa and provide insights into their secondary metabolites as alternative options in antibiotic therapy against multi-drug-resistant bacteria. Additionally, synergism between plant secondary metabolites and antibiotics has been discussed.

Self-assembled renewable nano-sized pentacyclic triterpenoid maslinic acids in aqueous medium for anti-leukemic, antibacterial and biocompatibility studies: An insight into targeted proteins-compound interactions based mechanistic pathway prediction through molecular docking

Maslinic acid is a naturally occurring dihydroxy, mono-carboxy bioactive triterpenoid. Its bulky structure was the main hindrance in the path of biological activity. Sodium and potassium salts of nano-sized triterpenoid maslinic acid were prepared from maslinic acid and its self-assembly property was studied in aqueous and aqueous-organic binary liquid mixtures. Morphology of the compounds studied by Field Emission Scanning Electron Microscopy (FESEM), Atomic Force Microscopy (AFM), High Resolution Transmission Electron Microscopy (HRTEM), Optical Microscopy, Fourier Transform Infrared Spectroscopy (FTIR) and X-ray diffraction (XRD) revealed vesicular morphology of the self-assemblies. Selective cytotoxicity was performed in leukemic (K-562 and KG-1a) and PBMC cells. Among the three self-assemblies (maslinic acid 1, sodium maslinate 2 and potassium maslinate 3), sodium maslinate 2 showed better antileukemic efficacy. Sodium maslinate 2 induced apoptosis in leukemic cells by elevating ROS levels and disrupting the cellular antioxidant system. From the in-silico studies, it was confirmed that 2 interacted with extrinsic and intrinsic apoptotic proteins of leukemic cells and killed those cells by inducing apoptotic pathways. The compounds 1, 2 and 3 showed significant antibacterial efficacy against E.coli strain through binding with several periplasmic membrane fusion protein (MFP) and limiting the efflux system leading to arrestation of antimicrobial resistance.

Isolation and anticancer activity of quercetin from Acalypha indica L. against breast cancer cell lines MCF-7 and MDA-MB-231

In this study, the active components of the plant were carefully extracted and identified using three solvent systems. After extraction, we used solvent systems to further purify the main flavonoid chemical constituent. As a result of our analytical strategy, which included HPLC analysis, MS/MS spectroscopic analysis, and NMR data-based constructions, quercetin was determined to be the main chemical constituent. Our study suggests the potential therapeutic advantages of quercetin, a compound found in the leaves of Acalypha indica, for treating breast cancer cell lines MCF-7 and MDA-MB-231. Our comparison of Quercetin to the regularly prescribed medicine Doxorubicin shows that it has the capacity to inhibit MCF-7 and MDA-MB-231 cells. Measurements of apoptosis and cell cycle phase showed this to be the case. Furthermore, a ladder that formed as a result of cellular damage brought on by ROS provided further proof of the drug's impact on DNA integrity. Notably, pro-apoptotic proteins displayed increased apoptosis activity in cells treated with quercetin. Given that it is extracted from plants and has less adverse effects than other compounds, quercetin is a viable option for further clinical study. The objective is to fight breast cancer, one of the most prevalent diseases in the world and a main cause of death for women. Thus, our research makes a significant addition to the ongoing search for potent, plant-based breast cancer treatments.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-023-03705-w.

Chenopodium murale Juice Shows Anti-Fungal Efficacy in Experimental Oral Candidiasis in Immunosuppressed Rats in Relation to Its Chemical Profile

Chenopodium murale (Syn. Chenopodiastrum murale) (amaranthaceae) is used in the rural Egypt to treat oral ulcers in newborn children. The current study aimed to discover new natural products suitable for treating candidiasis disease with minimal side effects. Characterization of bioactive compounds by LC-QTOF-HR-MS/MS from Chenopodium murale fresh leaves' juice (CMJ) was carried out in order to elucidate their potential anti-fungal and immunomodulatory effects in oral candidiasis in immunosuppressed rats. An oral ulcer candidiasis model was created in three stages: (i) immunosuppression by drinking dexamethasone (0.5 mg/L) for two weeks; (ii) Candida albicans infection (3.00 × 10⁶ viable cell/mL) for one week; and (iii) treatment with CMJ (0.5 and 1.0 g/kg orally) or nystatin (1,000,000 U/L orally) for one week. Two doses of CMJ exhibited antifungal effects, for example, through a significant reduction in CFU/Petri (236.67 ± 37.86 and 4.33 ± 0.58 CFU/Petri), compared to the Candida control (5.86 × 10⁴ ± 1.21 CFU/Petri), p ≤ 0.001. In addition, CMJ significantly induced neutrophil production (32.92% ± 1.29 and 35.68% ± 1.77) compared to the Candida control level of 26.50% ± 2.44. An immunomodulatory effect of CMJ at two doses appeared, with a considerable elevation in INF-γ (103.88 and 115.91%), IL-2 (143.50, 182.33%), and IL-17 (83.97 and 141.95% Pg/mL) compared with the Candida group. LC-MS/MS analysis operated in negative mode was used for tentative identification of secondary (SM) metabolites based on their retention times and fragment ions. A total of 42 phytoconstituents were tentatively identified. Finally, CMJ exhibited a potent antifungal effect. CMJ fought Candida through four strategies: (i) promotion of classical phagocytosis of neutrophils; (ii) activation of T cells that activate IFN-γ, IL-2, and IL-17; (iii) increasing the production of cytotoxic NO and H₂O₂ that can kill Candida; and (iv) activation of SOD, which converts superoxide to antimicrobial materials. These activities could be due to its active constituents, which are documented as anti-fungal, or due to its richness in flavonoids, especially the active compounds of kaempferol glycosides and aglycone, which have been documented as antifungal. After repetition on another type of small experimental animal, their offspring, and an experimental large animal, this study may lead to clinical trials.

Antifungal Activity of Plant Secondary Metabolites on Candida albicans: An Updated Review

Fungal infections have been increasing continuously worldwide, especially in immunocompromised individuals. Fungi, regarded as eukaryotic pathogens, have many similarities to the host cells, which inhibit anti-fungal drug development progress. Various fungal model systems have been studied, and it was concluded that Candida spp. is the most common disease-causing fungus. Candida species are well known to cause infections not only in our mouth, skin, and vagina, but they are also a frequent cause of life-threatening hospital bloodstream infections. The morphological and developmental pathways of Candida have been studied extensively, providing insight into the fungus development. Candida albicans is known to be the most pathogenic species responsible for a variety of infections in humans. Conventional anti-fungal drugs, mainly azoles drugs available in the market, have been used for years developing resistance in C. albicans. Hence, the production of new anti-fungal drugs, which require detailed molecular knowledge of fungal pathogenesis, needs to be encouraged. Therefore, this review targets the new approach of "Green Medicines" or the phytochemicals and their secondary metabolites as a source of novel anti-fungal agents to overcome the drug resistance of C. albicans, their mechanism of action, and their combined effects with the available anti-fungal drugs.

Evaluation of the antimicrobial effects of Capsicum, Nigella sativa, Musa paradisiaca L., and Citrus limetta: A review

The extensive use of antibiotics and vaccines against microbial infections can result in long-term negative effects on humans and the environment. However, there are a number of plants that have antimicrobial effects against various disease-causing microbes such as bacteria, viruses, and fungi without negative side effects or harm to the environment. In this regard, four particular plants- Capsicum, Nigella sativa, Musa paradisiaca L., and Citrus limetta have been widely considered due to their excellent antimicrobial effect and ample availability. In this review, we discuss their antimicrobial effects due to the presence of thymoquinone, p-cymene, pinene, alkaloids, limonene, camphene, and melanin. These antimicrobial compounds disrupt the cell membrane of microbes, inhibit cellular division, and form biofilm in bacterial species, eventually reducing the number of microbes. Extraction of these compounds from the respective plants is carried out by different methods such as soxhlet, hydro-distillation, liquid-liquid extraction (LLE), pressurized liquid extraction (PLE), solid-phase extraction (SPE), supercritical fluid extraction (SFE), pulsed electric field (PEF), microwave-assisted extraction (MAE), enzyme-assisted extraction (EAE), ultrasound-assisted extraction (UAE), and high-voltage electrical discharge. Suitable selection of the extraction technique highly depends upon the associated advantages and disadvantages. In order to aid future study in this field, this review paper summarizes the advantages and disadvantages of each of these approaches. Additionally, the discussion covers how antimicrobial agents destroy harmful bacteria. Thus, this review offers in-depth knowledge to researchers on the antibacterial properties of Capsicum, Nigella sativa, Musa paradisiaca L. peels, and Citrus limetta.

Antibacterial and anti-trichomunas characteristics of local landraces of Lawsonia inermis L

Background

Henna (Lawsonia inermis) with anti-bacterial properties has been widely used in traditional medicine especially Persian medicine. Henna oil is suggested for diseases of infectious origin, such as cervical ulcers. Group B Streptococcus agalactiae, Pseudomonas aeruginosa and, Trichomonas vaginalis are involved in the infection of women especially cervicitis. Henna grows in dry and tropical regions. The main important landraces of henna landraces are cultivated in Kerman, Sistan and Baluchestan, Hormozgan, and Bushehr provinces in Iran.

Proper use of antimicrobial agents, use of new antimicrobial strategies, and alternative methods, such as herbal methods may help reduce drug resistance in the future. This study’s objective was to investigate the anti-Trichomonas vaginalis activity of three different henna landraces and antimicrobial effects against group B Streptococcus agalactiae and, Pseudomonas aeruginosa.

Methods

Total phenol content was measured by Folin ciocaltu method. Antibacterial effect of landraces of Henna against P. aeruginosa and S. agalactiae were assayed by well diffusion method and minimal inhibitory concentration assessments were done using the broth micro-dilution technique. Anti-Trichomonas effect of Henna landraces were assayed by Hemocytometery method.

Results

Total phenol content of Shahdad, Rudbar-e-Jonub, and Qaleh Ganj was 206.51, 201.96, and 254.85 μg/ml, respectively. Shahdad, Rudbar-e-Jonub, and Qaleh Ganj had MIC against GBS at 15, 15 and, 4 μg/ml. The growth inhibition diameter of the most effective henna (Shahdad landrace) at a concentration of 20 μg/ml on P. aeruginosa was 2.46 ± 0.15 cm and in the MIC method at a concentration of 5 μg/ml of Shahdad landrace, P. aeruginosa did not grow. IC50 of shahdad Henna after 24 h, 48 h, and 72 h was 7.54, 4.83 and 20.54 μg/ml, respectively. IC50 of Rudbar-e-Jonub extract was 5.76, 3.79 and 5.77 μg/ml in different days. IC50 of Qaleh Ganj extract was 6.09, 4.08 and 5.74 μg/ml in different days.

Conclusions

The amount of total phenol in Qaleh Ganj was higher than the other varieties. In the well diffusion method, Qaleh Ganj was more effective against group B Streptococcus (Gram-positive bacterium) than the other two landraces, and Shahdad landrace was more effective against P. aeruginosa (Gram-negative bacterium) than other. In the MIC method, the same result was obtained as in the well diffusion method, but at a lower concentration.

Bioactive compounds, antibacterial and antioxidant activities of methanol extract of Tamarindus indica Linn

Tamarindus indica is one of the tropical medicinal plants that has been attributed curative potential of numerous diseases by many rural dwellers. This study was designed to evaluate the antioxidant, antibacterial activities and also to determine the various chemical constituents responsible for its pharmacological activities. The methanol extract of Tamarindus indica fruit pulp was analyzed by Gas Chromatography/Mass Spectrometer to determine the volatile compounds present. The antioxidant activities were performed using DPPH and FRAP method and the antibacterial activity was tested against some common pathogens by macro broth dilution method. The GCMS analysis shows the presence of 37 compounds, out of which 14 had their peak area percentages ≥ 1% and only two compounds had no reported pharmacological activities. Most of the bioactive compounds including 5-Hydroxymethylfurfural (31.06%)-3-O-Methyl-d-glucose (16.31%), 1,6-anhydro-β-D-Glucopyranose (9.95%), 5-methyl-Furancarboxaldehyde (3.2%), Triethylenediamine (1.17%), 1-(2-furanyl)-1-Propcanone (2.18%), Methyl 2-furoate (3.14%), Levoglucosenone (3.21%), methyl ester-Hepta-2,4-dienoic acid, (8.85%), 2,3-dihydro-3,5-dihydrox-4H-Pyran-4-one (3.4%), O-α-D-glucopyranosyl-(1.fwdarw.3)-β-D-fructofuranosyl-α-D-Glucopyranoside (2.18%), n-Hexadecanoic acid (1.38%), 2-Heptanol, acetate (1.29%), 5-[(5-methyl-2-fur-2-Furancarboxaldehyde (1.08%), 3-Methyl-2-furoic acid (1.05%) and cis-Vaccenic acid (2.85%)have been reported with different activities such as antibacterial, antifungal, antitubercular, anticancer, antioxidant and other prophylactic activities. The extract demonstrated inhibitory potential against all tested pathogen. However, Plesiomonas shigellosis ATCC 15903 and Bacillus pumillus ATCC 14884 are more sensitive with the MIC of 0.22 and 0.44 mg/ml respectively. The antioxidant activity was relatively low due to the low phenolic content of the extract. This shows that there is a strong correlation between antioxidant activities and phenolic content. GC–MS analysis revealed the presence of bioactive phytoconstituents with various biological activities and this justifies the rationale behind its usage as a curative therapy by many local dwellers.

Phytochemical screening and antibacterial activity of Skimmia anquetilia N.P. Taylor and Airy Shaw: A first study from Kashmir Himalaya

The present study aimed to explore the antibacterial activity of various organic root extracts of Skimmia anquetilia N.P. Taylor and Airy Shaw and the identification of major functional groups and phytoconstituents through fourier transform infrared spectrometer (FTIR) and gas chromatography-mass spectrometer (GC-MS). The extracts were evaluated for antibacterial activity against multidrug-resistant (MDR) strains viz., Pseudomonas aeruginosa (MTCC424), Escherichia coli (MTCC739), Klebsiella pneumoniae (MTCC139), Salmonella typhi (MTCC3224), and Staphylococcus aureus (MTCC96). ESKAPE pathogens such as S. aureus, K. pneumoniae, and P. aeruginosa are responsible for a majority of all healthcare acquired infections. The ethyl acetate extract showed the highest zone of inhibition against P. aeruginosa (18 mm) followed by S. aureus (17 mm). The minimum inhibitory concentration (MIC) of ethyl acetate extract against strain of S. aureus (4 mg mL^-1) demonstrated therapeutically significant antibacterial activity. The FTIR spectra of root extracts revealed the occurrence of functional characteristic peaks of alcohols, carboxylic acids, aromatic compounds, alkanes, alkenes, and amines that indicates the presence of various metabolites in the extracts. The GC-MS investigation led to the identification of diverse phytoconstituents in each of the extracts with varying concentrations and molecular masses. The highest number of compounds were identified from the methanol extract (112), followed by n-hexane extract (88) and ethyl acetate extract (74). The most predominant compounds were 5, 10-pentadecadien-1-ol, (Z,Z)-(33.94%), n-hexadecanoic acid (13.41%) in n-hexane extract, 5,10-pentadecadien-1-ol, (Z,Z)-(10.48%), 1-hexyl-2-nitrocyclohexane (7.94%) in ethyl acetate extract, and 1-hexyl-2-nitrocyclohexane (15.43%), cis,cis,cis-7,10,13-hexadecatrienal (13.29%) in methanol extract. The results of the present study will create a way for the invention of plant-based medicines for various life-threatening microbial infections using S. anquetilia, which may lead to the development of novel drugs against drug-resistant microbial infections.

Anti-vibrio and immune-enhancing activity of medicinal plants in shrimp: A comprehensive review

Disease epidemics in shrimp aquaculture increase apace with the development of aquaculture systems throughout the world. The disease caused by Vibrio spp. (vibriosis) is considered the most devastating, which has made it the most feared bacterial disease in the shrimp sector. In aquaculture, several strategies have already been applied to control Vibrio strains, including chemicals, probiotics, antibiotics, natural products from plants, including plant oils; hence, there has been considerable attention for using plants in shrimp aquaculture to provide sustainable, eco-friendly and safe compounds, such as alkaloids, saponins, terpenoids and flavonoids for replacing chemical compounds and antibiotics in current aquaculture. Medicinal plants may also have immunostimulating activity, increase growth and resistance in shrimps. The present paper aims to review the inhibition of Vibrio spp. in shrimp by medicinal plants, using both in vitro or/and in vivo techniques. Several medicinal plants appear capable of inhibiting growth of Vibrio pathogens outside living shrimp or in the body of shrimp, through enhancing growth and immune capacity when shrimps are fed or injected with them. In the current review Gracilaria spp. (Gracilariaceae family) and Sargassum spp. (family Sargassaceae) have been used most for in vitro and in vivo experiments. Among the terrestrial plants, Eucalyptus camaldulensis, Psidium guajava, Rhodomyrtus tomentosa, and Syzygium cumini (Myrtaceae family) had significant activity against Vibrio.

Evaluation of the synergistic antimicrobial effect of folk medicinal plants with clindamycin against methicillin-resistant Staphylococcus aureus strains

Antibiotic resistance has become a major worldwide priority, and identifying natural antimicrobial compounds may help overcome this problem. In this study, ethanolic extracts of 12 plants commonly used in traditional medicine were tested against two strains of methicillin-resistant Staphylococcus aureus (ATCC 33591 and ATCC 43300) in terms of minimum inhibitory concentrations (MICs). Furthermore, the effect of combining plant extracts with clindamycin antibiotic was also investigated using the checkerboard method. Among the tested plants, Camellia sinensis, Thymus vulgaris, Rosmarinus officinalis and Salvia officinalis exhibited potent inhibitory activity against both strains with MICs ranges (125-500 µg ml^-1 ). Synergistic activity was confirmed for the four plants combined with clindamycin with fractional inhibitory concentration index <0·5. However, no antagonistic activity was found for these combinations. Our findings suggest that using an antibiotics-plants combination might be a successful technique to reduce antibiotic consumption, which would overcome the antibiotics resistance or delay its onset.

Enhanced bone tissue regeneration via bioactive electrospun fibrous composite coated titanium orthopedic implant

One of the very reliable, attractive, and cheapest techniques for synthesizing nanofibers for biomedical applications is electrospinning. Here, we have created a novel nanofibrous composite coated Ti plate to mimic an Extra Cellular Matrix (ECM) of native bone in order to enhance the bone tissue regeneration. An electrospun fibrous composite was obtained by the combination of minerals (Zn, Mg, Si) substituted hydroxyapatite (MHAP)/Polyethylene Glycol (PEG)/Cissus quadrangularis (CQ) extract. Fibrous composite's functionality, phase characteristics, and morphology were evaluated by FT-IR, XRD, and SEM techniques, respectively. The average fiber diameter of MHAP/PVA had decreased from ~274 to ~255 nm after incorporating PEG polymer. That further increased from ~255 to ~275 nm after adding CQ extract. Besides the bioactivity in SBF solution, the degradable nature was confirmed by immersing the fibrous composite in Tris-HCL solution. The degradable studies evaluate that the composite was degraded depending on time, and it degrades about 9.42% after 7 days of immersion. Osteoblasts like MG-63 cells differentiation, proliferation, and calcium deposition were also determined. These results show that this new fibrous composite exhibits advanced osteoblasts properties. Thus, we concluded that this new fibrous scaffold coated Ti implant could act as a better implant to mimic ECM of bone structure and to improve osteogenesis during bone regeneration.

Formulation, Characterization and Antimicrobial efficacy of Aegle marmelos Essential oil nanogel

Objective: Aegle marmelos (L.) Correa has been widely used in Indian traditional medicine and has many reported pharmacological activities. The aim of this research was to formulate solid lipid nanoparticles (SLNs) of Aegle oil (AO) that enhanced the beneficial antimicrobial activity of the oil. Methods: The chemical composition of Aegle leaf essential oil was analysed by GC-MS. Additionally, a phytochemical study of A. marmelos methanolic leaf extract was conducted using Folin-Ciocalteu colorimetric assay for determination of total phenolic content as well as ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-ESI-MS-MS) analyses for identification of individual components. Six formulations of AO-loaded SLNs (AO-SLNs) were prepared by a double emulsification method. The particle size, zeta potential (ZP), polydispersibility index (PDI) and drug encapsulation efficiency (EE) of the SLNs were determined. The morphology of the SLNs was observed by transmission electron microscopy (TEM). The antimicrobial activity of AO and AO-SLNs was assessed using disc diffusion method. Results: Thirty-two compounds were identified in the Aegle oil, of which Δ-carene and α-phellandrene were the most abundant (48.14% and 34.14%, respectively). The estimated total phenolic content was 968mg gallic acid equivalents (GAE)/g, while UPLC-ESI-MS-MS led to the tentative characterization of thirteen metabolites. The SLNs showed ZP, PDI and EE 125 ± 0.22nm, –37.85, 0.282, and 92%, respectively. AO and AO-SLNs showed significant antimicrobial activity, and the SLNs could sustain the release of AO from their gel vehicles. Conclusion: Our results provide evidence for the application of AO-SLNs in topical and transdermal delivery systems.

Plant-Based Phytochemicals as Possible Alternative to Antibiotics in Combating Bacterial Drug Resistance

The unprecedented use of antibiotics that led to development of resistance affect human health worldwide. Prescription of antibiotics imprudently and irrationally in different diseases progressed with the acquisition and as such development of antibiotic resistant microbes that led to the resurgence of pathogenic strains harboring enhanced armors against existing therapeutics. Compromised the treatment regime of a broad range of antibiotics, rise in resistance has threatened human health and increased the treatment cost of diseases. Diverse on metabolic, genetic and physiological fronts, rapid progression of resistant microbes and the lack of a strategic management plan have led researchers to consider plant-derived substances (PDS) as alternative or in complementing antibiotics against the diseases. Considering the quantitative characteristics of plant constituents that attribute health beneficial effects, analytical procedures for their isolation, characterization and phytochemical testing for elucidating ethnopharmacological effects has being worked out for employment in the treatment of different diseases. With an immense potential to combat bacterial infections, PDSs such as polyphenols, alkaloids and tannins, present a great potential for use, either as antimicrobials or as antibiotic resistance modifiers. The present study focuses on the mechanisms by which PDSs help overcome the surge in resistance, approaches for screening different phytochemicals, methods employed in the identification of bioactive components and their testing and strategies that could be adopted for counteracting the lethal consequences of multidrug resistance.

Efficacy and Mechanisms of Flavonoids against the Emerging Opportunistic Nontuberculous Mycobacteria

Nontuberculous mycobacteria (NTM) are the causative agent of severe chronic pulmonary diseases and is accountable for post-traumatic wound infections, lymphadenitis, endometritis, cutaneous, eye infections and disseminated diseases. These infections are extremely challenging to treat due to multidrug resistance, which encompasses the classical and existing antituberculosis agents. Hence, current studies are aimed to appraise the antimycobacterial activity of flavonoids against NTM, their capacity to synergize with pharmacological agents and their ability to block virulence. Flavonoids have potential antimycobacterial effects at minor quantities by themselves or in synergistic combinations. A cocktail of flavonoids used with existing antimycobacterial agents is a strategy to lessen side effects. The present review focuses on recent studies on naturally occurring flavonoids and their antimycobacterial effects, underlying mechanisms and synergistic effects in a cocktail with traditional agents.

Synergistic Antimicrobial and Antioxidant Properties of Coccinia grandis (L.) Voigt, Clerodendrum inerme (L.) Gaertn. and Acanthus ebracteatus Vahl. Extracts and Their Potential as a Treatment for Xerosis Cutis

BACKGROUND

A common health condition among older persons is xerosis cutis. Topical corticosteroid treatments are -associated with side effects. There is an unmet need for her-bal treatment alternatives. Coccinia grandis, Clerodendrum inerme and Acanthus ebracteatus are used to treat skin con-ditions in Thai traditional medicine. This study aimed to investigate their antimicrobial and antioxidant properties, synergistic properties as well as their cytotoxicity.

METHODS

-Ethanolic herbal extracts were used to perform minimal -inhibitory (MIC) and minimal bactericidal concentration (MBC) assays on common skin pathogens. Synergistic anti-microbial activity was evaluated by a chequerboard assay. Antioxidant and synergistic properties were assessed by a 1,1-diphenyl-2-picrylhydrazyl assay. Cytotoxicity was tested on normal adult human primary epidermal keratinocytes.

RESULTS

All extracts showed an inhibitory effect on growth of all microorganisms tested. MIC and MBC values ranged from 0.0625 to 32 mg/mL and from 0.0625 to >256 mg/mL, respectively. A. ebracteatus extract markedly demonstrated bactericidal activity against an methicillin-resistant Staphylococcus aureus strain. Additive antimicrobial activity was observed (fractional inhibitory concentration index values: 0.75-1). All extracts possessed antioxidant properties (IC50 values: 0.12-0.25 mg/L). However, antagonism was observed with paired extract combinations (combination index values: 1.025-1.455). The cell viability assay confirmed that herbal extracts were not cytotoxic.

CONCLUSIONS

Our results provide early findings of pharmacological activities to support a novel choice of herbal combinations as potential local skin treatment options for xerosis cutis.

Purpurin Esters Containing a Saturated Cyclic Fragment with Antimicrobial Activity

The present study is a continuation of the scientific research works for the synthesis of anthraquinonе-containing derivatives with cyclic ring systems by the interaction of 1,2,4-trihydroxyanthraquinone (purpurin) with cyclic carboxylic acid chlorides. Series of purpurin esters containing a saturated cyclic fragment was studied for antibacterial activity about museum strains of microorganisms. The effects of these preparations in vitro about Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 6633, Escherichia coli ATCC 25922, Pseudomonas aeruginosa АТСС 27853 and fungus Сandida albicans АТСС 10231 were studied. It has been found that the compounds with the cyclohexane fragment have possess an antimicrobial activity with strains of microorganisms Staphylococcus aureus АТСС 6538 for which the MIC value was 31.25 μg/ml.

Anti-Fungal Efficacy and Mechanisms of Flavonoids

The prevalence of fungal infections is growing at an alarming pace and the pathogenesis is still not clearly understood. Recurrence of these fungal diseases is often due to their evolutionary avoidance of antifungal resistance. The development of suitable novel antimicrobial agents for fungal diseases continues to be a major problem in the current clinical field. Hence, it is urgently necessary to develop surrogate agents that are more effective than conventional available drugs. Among the remarkable innovations from earlier investigations on natural-drugs, flavonoids are a group of plant-derived substances capable of promoting many valuable effects on humans. The identification of flavonoids with possible antifungal effects at small concentrations or in synergistic combinations could help to overcome this problem. A combination of flavonoids with available drugs is an excellent approach to reduce the side effects and toxicity. This review focuses on various naturally occurring flavonoids and their antifungal activities, modes of action, and synergetic use in combination with conventional drugs.

Efficacy and Mechanism of Traditional Medicinal Plants and Bioactive Compounds against Clinically Important Pathogens

Traditional medicinal plants have been cultivated to treat various human illnesses and avert numerous infectious diseases. They display an extensive range of beneficial pharmacological and health effects for humans. These plants generally synthesize a diverse range of bioactive compounds which have been established to be potent antimicrobial agents against a wide range of pathogenic organisms. Various research studies have demonstrated the antimicrobial activity of traditional plants scientifically or experimentally measured with reports on pathogenic microorganisms resistant to antimicrobials. The antimicrobial activity of medicinal plants or their bioactive compounds arising from several functional activities may be capable of inhibiting virulence factors as well as targeting microbial cells. Some bioactive compounds derived from traditional plants manifest the ability to reverse antibiotic resistance and improve synergetic action with current antibiotic agents. Therefore, the advancement of bioactive-based pharmacological agents can be an auspicious method for treating antibiotic-resistant infections. This review considers the functional and molecular roles of medicinal plants and their bioactive compounds, focusing typically on their antimicrobial activities against clinically important pathogens.

One-step Synthesis of Silver Nanoparticles Using Saudi Arabian Desert Seasonal Plant Sisymbrium irio and Antibacterial Activity Against Multidrug-Resistant Bacterial Strains

Globally, antimicrobial resistance has grown at an alarming rate. To combat the multidrug-resistant (MDR) superbugs, silver nanoparticles (Ag NPs) were synthesized using an aqueous leaf extract of seasonal desert plant Sisymbrium irio obtained from the central region of Saudi Arabia by a simple one-step procedure. The physical and chemical properties of the Ag NPs were investigated through ultraviolet visisble analysis (UV-vis), Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM) analysis. The UV-vis spectrum showed an absorption band at 426 nm. The XRD results showed a highly crystalline face-centered cubic structure. The surface morphology analyzed using SEM and TEM analyses showed the particle size to be in the range 24 nm to 50 nm. Various concentrations of Ag NPs were tested against MDR Pseudomonas aeruginosa and Acinetobacter baumanii that cause ventilator-associated pneumonia (VAP). American Type Culture Collection (ATCC) Escherichia coli-25922 was used as the reference control strain. The Ag NPs effectively inhibited tested pathogens, even at the lowest concentration (6.25 µg) used. The bacterial inhibitory zone ranged from 11–21 mm. In conclusion, the newly synthesized Ag NPs could be a potential alternative candidate in biomedical applications in controlling the spread of MDR pathogens.

Tecoma stans: Alkaloid Profile and Antimicrobial Activity

AIM

Tecoma stans (L.) Kunth is a promising species in the trumpet creeper family Bignoniaceae. This study aimed at showing the antibacterial and antifungal potentials of T. stans methanolic leaf extract (TSME) correlated to its phytoconstituents.

MATERIALS AND METHODS

The antimicrobial potential of TSME was evaluated using agar diffusion method. The main alkaloids were separated on silica gel column and identified using nuclear magnetic resonance spectral analysis. Molecular docking was performed for the isolated compounds against MurD ligase, penicillin-binding protein, and dihydropteroate synthase enzyme to rationalize the observed antibacterial effect.

RESULTS AND DISCUSSION

TSME showed significant antibacterial effect against all tested microorganisms with comparable minimum inhibitory concentration (MIC) to the ampicillin and gentamicin with MIC values ranging between 0.98 and 1.95 µg/mL, in addition to a promising antifungal effect when compared to amphotericin with MIC values 3.9 and 15.63 µg/mL for Aspergillus flavus and Candida albicans, respectively. Several alkaloids were separated, purified, and identified as tecostanine, 4-OH tecomanine, 5-hydroxyskytanthine, and tecomanine, which were previously isolated from T. stans. The docking study showed that the alkaloids bind in a similar fashion to the co-crystallized ligands of the crystal structures of MurD ligase. The binding poses and scores in the case of penicillin-binding protein and dihydropteroate synthase did not match the co-crystallized ligands in their crystal structures. The in silico results suggest an antibacterial mechanism that involves the inhibition of MurD ligase.

CONCLUSION

T. stans alkaloids could represent the basic skeleton for a powerful antimicrobial agent.

In Vitro Antioxidant and Bactericidal Efficacy of 15 Common Spices: Novel Therapeutics for Urinary Tract Infections?

Background and Objectives: Bacterial urinary tract infection (UTI) is the most common ailment affecting all age groups in males and females. The commercial antibiotics usage augments antibiotics resistance and creates higher recurrence rates of such communal infections. Hence, this study is aimed at investigating the antibacterial and antioxidant potentials of 15 common spices against 11 UTI-causing bacterial pathogens. Materials and Methods: The antioxidant potential of the methanolic extracts was analyzed as contents of total phenols and flavonoids; radical scavenging, total reducing power, the ferric reducing power assay. Urinary pathogens were subjected to spice extracts to investigate antibacterial assays. Results: Preliminary phytochemical study of spices was performed to find those containing alkaloids, flavonoids, phenolic compounds, and steroids that can be recognized for their noteworthy bactericidal effects. The outcome of the antioxidative potential from the four methods demonstrated the sequence of potent antioxidant activity: Acorus calamus >Alpinia galanga > Armoracia rusticana > Capparis spinosa > Aframomum melegueta. The total polyphenols and flavonoids in the studied species positively correlated with their antioxidant properties. The four most effective spices (A. calamus, A. galanga, A. rusticana, and C. spinosa) had a zone of inhibition of at least 22 mm. A. calamus, A. melegueta, and C. spinosa had the lowest minimum inhibitory concentration (MIC) value against Enterobacter aerogenes, Staphylococcus aureus and Proteus mirabilis. All 15 spices had the lowest minimum bactericidal concentration (MBC) value against most of the pathogenic bacteria. Conclusion: The four highly potent and unique spices noted for the in vitro control of UTI-causing pathogens could be pursued further in the development of complementary and alternative medicine against UTI-causing pathogens.

Antifungal Efficacy of Marine Macroalgae against Fungal Isolates from Bronchial Asthmatic Cases

Fungal sensitization is very common in bronchial asthmatic cases, and the connection with airway colonization by fungi remains uncertain. Antifungal therapy failure is a significant fraction of the cost and morbidity and mortality in the majority of the asthmatic cases. Hence, the present study aimed to investigate the antifungal activity of five marine macroalgae—Acanthaophora specifera, Cladophoropsis sp., Laurencia paniculata, Tydemania sp., and Ulva prolifera—which were tested on selected fungal pathogens isolated from 15 sputum of 45 bronchial asthmatic patients. The highest antifungal activity was observed in ethanol fractions of L. paniculata followed by U. prolifera, Cladophoropsis sp., A. specifera, and Tydemania sp. The minimum fungicidal concentration and minimum inhibitory concentration values of the ethanolic fractions of algal species were found to be 125–1000 µg/mL and 125–500 µg/mL, respectively. The algal extracts contained terpene alcohol, diterpene, steroids, sesquiterpene, and sesquiterpene alcohol, as determined by GC–MS/MS analyses. The present study shows that the marine macroalgae containing bioactive compounds had excellent inhibitory activity against a variety of fungal pathogens, which may be useful for combating fungal infections and recovering from chronic asthmatic states.

Cytotoxicity and Proapoptotic Effects of Allium atroviolaceum Flower Extract by Modulating Cell Cycle Arrest and Caspase-Dependent and p53-Independent Pathway in Breast Cancer Cell Lines

Breast cancer is the second leading cause of cancer death among women and despite significant advances in therapy, it remains a critical health problem worldwide. Allium atroviolaceum is an herbaceous plant, with limited information about the therapeutic capability. We aimed to study the anticancer effect of flower extract and the mechanisms of action in MCF-7 and MDA-MB-231. The extract inhibits the proliferation of the cells in a time- and dose-dependent manner. The underlying mechanism involved the stimulation of S and G2/M phase arrest in MCF-7 and S phase arrest in MDA-MB-231 associated with decreased level of Cdk1, in a p53-independent pathway. Furthermore, the extract induces apoptosis in both cell lines, as indicated by the percentage of sub-G0 population, the morphological changes observed by phase contrast and fluorescent microscopy, and increase in Annexin-V-positive cells. The apoptosis induction was related to downregulation of Bcl-2 and also likely to be caspase-dependent. Moreover, the combination of the extract and tamoxifen exhibits synergistic effect, suggesting that it can complement current chemotherapy. LC-MS analysis displayed 17 major compounds in the extract which might be responsible for the observed effects. Overall, this study demonstrates the potential applications of Allium atroviolaceum extract as an anticancer drug for breast cancer treatment.

Antimicrobial and antibiofilm activities of nanoemulsions containing Eucalyptus globulus oil against Pseudomonas aeruginosa and Candida spp

Candida species are the main responsible microorganisms for causing fungal infections worldwide, and Candida albicans is most frequently associated with infectious processes. Pseudomonas aeruginosa is a gram-negative bacterium commonly found in immunocompromised patients. The infection persistence caused by these microorganisms is often related to antimicrobial resistance and biofilm formation. In this context, the objective of the present study was to prepare and characterize nanoemulsions containing Eucalyptus globulus oil and to verify its antimicrobial and antibiofilm activities against P. aeruginosa and Candida spp. The nanoemulsions had a size of approximately 76 nm, a polydispersity index of 0.22, a zeta potential of - 9,42 mV and a pH of approximately 5.0. The E. globulus oil was characterized by gas chromatography, being possible to observe its main components, such as 1-8-Cineol (75.8%), p- Cymene (7.5%), α-Pinene (7.4%) and Limonene (6.4%). The antimicrobial activity of the nanoemulsion was determined from the macrodilution tests and the cell viability curve, where the minimum fungicidal concentration of 0.7 mg/mL for C. albicans and 1.4 mg/mL for C. tropicalis and C. glabrata were obtained. However, the nanoemulsions did not present antimicrobial activity against P. aeruginosa, since it contains only 5% of the oil, being ineffective for this microorganism. The nanoencapsulated oil action against the formed biofilm was evaluated by atomic force microscopy and calcofluor staining, and the nanoemulsion was more efficient for two of the three Candida species when compared to free oil.

S, M. V, S. R. S, P. M, V. R, Valiyaveettil S. Larvicidal, super hydrophobic and antibacterial properties of herbal nanoparticles from Acalypha indica for biomedical applications

Herbal nanoparticles usingAcalypha indicaleaves are investigated and found to possess superior larvicidal, water repellent and antimicrobial properties for biomedical applications.