Green synthesis of silver, starch, and zinc oxide mediated nanoparticles with probiotics and plant extracts, their characterization and anti-bacterial activity

Nanotechnology has various applications in all branches of science, including engineering, medicine, pharmacy, and other related fields. Conventional techniques, such as the chemical reduction approach, which produces nanoparticles (NPs) using various hazardous chemicals, offer several health risks due to their toxicity and raise serious environmental concerns. In contrast, other techniques are expensive and need a lot of energy. More than 70 % of pathogenic bacterial strains have developed resistance to at least one class of antibiotics, leading to an increase in life-threatening bacterial infections that pose a significant health risk. However, the creation of NPs by biogenic synthesis is risk-free for the environment and clean enough for biological use. This study was aimed at synthesis of novel Moringa oleifera mediated starch capped silver-zinc NPs and green synthesis of ZnO nanoparticles from Aloe vera, papaya, and Lactobacillus plantarum. Antimicrobial activity of both NPs was tested against Gram-negative antibiotic-resistant bacteria Pseudomonas aeruginosa, Gram-positive bacteria Staphylococcus aureus (ATCC 6538), and two foodborne pathogens Listeria monocytogenes and Campylobacter jejuni. Ultraviolet-visible spectroscopy, Fourier Transform Infrared Spectroscopy, and Scanning Electron Microscopy were used for characterization. Majority of the research studies stress the flexibility, repeatability, and desirable features of the metals, polymers, and plant components employed in the production of biomedical nanoparticles. Such an intuitive approach provides several advantages, particularly a reasonable total expense, compliance with healthcare and pharmaceutical implementations, and the ability to produce massive volumes for industrial use. The novelty of the presented work lies in the unusual combination of silver, starch, and zinc oxide nanoparticles using Moringa oleifera, which is an eco-friendly alternative to chemical-based methods. This research exhibits the formation of well-defined nanoparticles with strong antibacterial activity against a wide range of pathogens, giving us insights into their potential applications in various biomedical fields.

Clay-reinforced PVC composites and nanocomposites

Clay-reinforced polyvinyl chloride (PVC) composites and nanocomposites are one of the newest and most important compounds studied and used in various applications, including the biomedical, automotive industry, water treatment, packaging, fire retarding, and construction. The most important clays used in the synthesis of these composites are Bentonite, Montmorillonite, Kaolinite, and Illite. The addition of these nanoclays to the PVC matrix improves mechanical properties, thermal stability, and yellowness index properties. In this chapter, a detailed study of PVC and its properties, types of nanoclays and their properties, modification of nanoclays, production methods of composites, and nanocomposites of PVC/clay, their characterization, and applications have been performed. Herein, the types, properties, and applications of PVC/clay nanocomposites, as well as their challenges and future remarks, are reviewed.

Moringa oleifera Gum-Assisted Synthesis and Characterization of CoAgxFe2-xO4: Insight into Structural, Magnetic, Optical, and Biomedical Properties

The sol-gel method was employed to prepare nano CoFe2O4 and silver-substituted CoFe2O4 nanohybrids (CoAgxFe2-xO4, x = 0, 0.1, 0.2, 0.3, 0.4) utilizing Moringa oleifera gum as biofuel. The morphology, size, shape, magnetic, optical, and functional groups of the crystallites were determined using various techniques such as UV-visible, Fourier transform infrared, X-ray diffraction, Rietveld, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, and photoluminescence. The produced nanoferrite has a spherical shape with cubic spinal structures. The optical properties were investigated in two different bands in the photoluminescence emission spectra at 469 and 493 nm. Saturation magnetization (Ms) and coercivity (Hc) decrease as the Ag content increases significantly. Furthermore, antibacterial (Gram-positive bacteria bacterial strains, Bacillus subtilis and Staphylococcus aureus, and Gram-negative bacterial strains, Pseudomonas aeruginosa, and Escherichia coli), antibiofilm activity (E. coli), and antioxidant (DPPH) activities were investigated. The substantial increase in the silver content offers a constructive impact on studied biomedical activities. These findings encourage additional research into the use of hybrid nanoparticles (an amalgamation of ferrite and a noble metal) in biomedical and pharmaceutical applications.

Bioactive Compounds in Moringa oleifera: Mechanisms of Action, Focus on Their Anti-Inflammatory Properties

Moringa oleifera (M. oleifera) is a tropical tree native to Pakistan, India, Bangladesh, and Afghanistan; it is cultivated for its nutritious leaves, pods, and seeds. This scientific study was conducted to outline the anti-inflammatory properties and mechanisms of action of bioactive compounds from M. oleifera. The existing research has found that the plant is used in traditional medicine due to its bioactive compounds, including phytochemicals: flavonoids and polyphenols. The compounds are thought to exert their anti-inflammatory effects due to: (1) inhibition of pro-inflammatory enzymes: quercetin and kaempferol inhibit the pro-inflammatory enzymes (cyclooxygenase and lipoxygenase); (2) regulation of cytokine production: isothiocyanates modulate signaling pathways involved in inflammation, such as the nuclear factor-kappa B (NF-kappa B) pathway; isothiocyanates inhibit the production of pro-inflammatory cytokines such as TNF-α (tumor necrosis factor α) and IL-1β (interleukin-1β); and (3) antioxidant activity: M. oleifera contains flavonoids, polyphenols, known to reduce oxidative stress and inflammation. The review includes M. oleifera's effects on cardiovascular protection, anti-hypertensive activities, type 2 diabetes, inflammatory bowel disease, and non-alcoholic fatty liver disease (NAFLD). This research could prove valuable for exploring the pharmacological potential of M. oleifera and contributing to the prospects of developing effective medicines for the benefit of human health.

Innovative Materials with Possible Applications in the Wound Dressings Field: Alginate-Based Films with Moringa oleifera Extract

For a long time, biopolymers have proven their effectiveness in the development of materials with various applications, lately those intended for the biomedical and pharmaceutical industries, due to their high biocompatibility and non-toxic, non-allergenic, and non-immunogenic nature. The ability to incorporate various active substances in this matrix has yielded materials with characteristics that are far superior to those of classic, conventional ones. The beneficial effects of consuming Moringa oleifera have promoted the use of this plant, from Ayurvedic to classical medicine. The addition of such compounds in the materials intended for the treatment of surface wounds may represent the future of the development of innovative dressings. This study followed the development of materials based on sodium alginate and moringa powder or essential oil for use as dressings, pads, or sheets. Thus, three materials with the addition of 10-30% moringa powder and three materials with the addition of 10-30% essential oil were obtained. The data were compared with those of the control sample, with sodium alginate and plasticizer. The microtopography indicated that the materials have a homogeneous matrix that allows them to incorporate and maintain natural compounds with prolonged release. For example, the sample with 30% moringa essential oil kept its initial shape and did not disintegrate, although the swelling ratio value reached 4800% after 20 min. After testing the mechanical properties, the same sample had the best tensile strength (TS = 0.248 MPa) and elongation (31.41%), which is important for the flexibility of the dressing. The same sample exhibited a very high antioxidant capacity (60.78% inhibition). The materials obtained with moringa powder added presented good values of physical and mechanical properties, which supports their use as wound dressings for short-term application and the release of embedded compounds. According to the obtained results, all the biopolymeric materials with moringa added can be used as dressings for different wound types.

Biogenic sunflower oil-chitosan decorated fly ash nanocomposite film using white shrimp shell waste: Antibacterial and immunomodulatory potential

A new sunflower oil-chitosan decorated fly ash (sunflower oil/FA-CSNPs) bionanocomposite film was synthesized using the extract of Litopenaeus vannamei (White shrimp) and evaluated as an antibacterial and immunomodulatory agent. Fly ash-chitosan nanoparticles were produced by using chitosan (CS) isolated from white shrimp extract, glacial acetic acid and sodium tripolyphosphate solution as cross-linkage. The ultrafine polymeric sunflower oil-CS film was fabricated by treating fly ash-chitosan nanoparticles with sunflower oil in glacial acetic acid under continuous stirring for 24 h. The nanostructure of the fabricated polymeric film was confirmed and characterized by different microscopic and spectroscopic approaches. The surface morphology of pre-synthesized bionanocomposite film was found to be homogenous, even and without cracks and pores. The crystallinity of formed bionanocomposite film was noticed at angles (2θ) at 12.65°, 15.21°, 19.04°, 23.26°, 34.82°, and 37.23° in the XRD spectrum. The fabricated film displayed excellent stability up to 380 ⁰C. The formed sunflower oil/FA-CSNPs bionanocomposite film showed promising antibacterial towards Bacillus subtilis with highest zone of inhibition of 34 mm and Pseudomonas aeruginosa with zone of inhibition of 28 nm. The as-synthesized bionanocomposite film exhibited highest cell viability effect (98.95%), followed by FA-CSNPs (83.25%) at 200 μg mL-1 concentrations. The bionanocomposite film exerted notable immunomodulatory effect by promoting phagocytosis and enhancing the production of cytokines (NO, IL-6, IL-1β, and TNF-α) in macrophage-derived RAW264.7 cell line.

Modification of Poly(vinyl chloride) with Bio-Based Cassia Oil to Improve Thermo-Mechanical and Antimicrobial Properties

The purpose of this study was to modify plasticised PVC to obtain a material with antimicrobial properties and selected mechanical properties. Natural cassia oil (CO) was used to modify plasticised PVC materials. The modified material was produced by extrusion. The introduced modifier had a maximum concentration of 20 phr. Rheological and mechanical properties were evaluated, and the glass transition temperature was determined. The antioxidant and antimicrobial activity of the agar diffusion method was investigated by analysing the growth inhibition zones against Enterococcus faecalis and Listeria monocytogenes. A favourable effect of the cassia oil content on the increase in antioxidant activity of the developed polymeric materials was found with an increase in the modifier content and the duration of action (30 days). The largest growth restriction zones were observed for L. monocytogenes, i.e., they showed the highest sensitivity to the modified material. The simultaneous decrease in modulus of elasticity, increase in elongation at break, and decrease in T_g indicate that the modifier has a plasticising effect on PVC. The developed material may find application as an active and/or functional material, especially as an emitter of antimicrobial agents, in the packaging used to store minimally processed food.

Green Biosynthesis of Silver Nanoparticles from Moringa oleifera Leaves and Its Antimicrobial and Cytotoxicity Activities

The plant occupied the largest area in the biosynthesis of silver nanoparticles, especially the medicinal plants, and it has shown great potential in biotechnology applications. In this study, green synthesis of silver nanoparticles from Moringa oleifera leaves extract and its antifungal and antitumor activities were investigated. The formation of silver nanoparticles was observed after 1 hour of preparation color changing. The ultraviolet and visible spectrum, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy techniques were used to characterize synthesis particles. Ultraviolet and visible spectroscopy showed a silver surface plasmon resonance band at 434 nm. Fourier transform infrared analysis shows the possible interactions between silver and bioactive molecules in Moringa oleifera leaves extracts, which may be responsible for the synthesis and stabilization of silver nanoparticles. X-ray diffraction showed that the particles were a semicubic crystal structure and with a size of 38.495 nm. Scanning electron microscopy imaging shows that the atoms are spherical in shape and the average size is 17 nm. The transmission electron microscopy image demonstrated that AgNPs were spherical and semispherical particles with an average of (50–60) nm. The nanoparticles also showed potent antimicrobial activity against pathogenic bacteria and fungi using the well diffusion method. Candida glabrata found that the concentration of 1000 μg/mL exhibited the highest inhibition. As for bacteria, the concentration of 1000 μg/mL appeared to be the inhibition against Staphylococcus aureus. Moringa oleifera AgNPs inhibited human melanoma cells A375 line significant concentration-dependent cytotoxic effects. The powerful bioactivity of the green synthesized silver nanoparticles from medical plants recommends their biomedical use as antimicrobial as well as cytotoxic agents.

Immunomodulatory and Antiprotozoal Potential of Fabricated Sesamum radiatum Oil/Polyvinylpyrrolidone/Au Polymeric Bionanocomposite Film

A unique morphological Sesamum radiatum oil/polyvinylpyrrolidone/gold polymeric bionanocomposite film was synthesized using the S. radiatum oil dispersed in a polymeric polyvinylpyrrolidone (PVP) matrix and decorated with gold nanoparticles (AuNPs). The chemical and physical characteristics as well as the thermal stability of the synthesized bionanocomposite film were investigated using various spectroscopic and microscopic techniques. The microscopic analysis confirmed well dispersed AuNPs in the PVP- S. radiatum oil matrix with particle size of 100 nm. Immunomodulatory and antiprotozoal potentials of the suggested bionanocomposite film were evaluated for lipopolysaccharide-induced BV-2 microglia and against L. amazonensis, L. mexicana promastigotes and T. cruzi epimastigotes, respectively. The results exerted outstanding reduction of inflammatory cytokines' (IL-6 and TNFα) secretions after pretreatment of bionanocomposite. The bionanocomposite exhibited large inhibitory effects on certain cell signaling components that are related to the activation of expression of proinflammatory cytokines. Additionally, AuNPs and bionanocomposite exhibited excellent growth inhibition of L. mexicana and L. amazonensis promastigotes with IC50 (1.71 ± 1.49, 1.68 ± 0.75) and (1.12 ± 1.10, 1.42 ± 0.69), respectively. However, the nanomaterials showed moderate activity towards T. cruzi. All outcomes indicated promising immunomodulatory, antiprotozoal, and photocatalytic potentials for the synthesized S. radiatum oil/PVP/Au polymeric bionanocomposite.

Bioactive components from Moringa oleifera seeds: production, functionalities and applications - a critical review

A readily distinguishable and indigenous member of the plant kingdom in the Indian subcontinent is the 'drumstick tree', i.e. Moringa oleifera Lam. In addition to India, this drought-tolerant and rapidly evolving tree is currently extensively disseminated across the globe, including subtropical and tropical areas. The plant boasts a high nutritional, nutraceutical and therapeutic profile, mainly attributing to its significant repertoire of the biologically active components in different parts: protein, flavonoids, saponins, phenolic acids, tannin, isothiocyanate, lipids, minerals, vitamins, amongst others. M. oleifera seeds have been shown to elicit a myriad of pharmacological potential and health benefits, including: antimicrobial, anticancer, antidiabetic, antioxidant, antihypertensive, anti-inflammatory and cardioprotective properties. Additionally, the seed cakes obtained from post-extraction process are utilized for: coagulation, flocculation and sedimentation purposes, benefiting effluent management and the purification of water, mainly because of their capability in eliminating microbes and organic matter. Despite the extraordinary focus on other parts of the plant, especially the foliage, the beneficial aspects of the seeds have not been sufficiently highlighted. The health benefits of bioactive components in the seeds are promising and demonstrate enough potential to facilitate the development of functional foods. In this review, we present a critical account of the types, characteristics, production and isolation of bioactive components from M. oleifera seeds. Furthermore, we appraise the: pharmacological activities, cosmetic, biodiesel, lubricative, modern farming, nutritive and wastewater treatment applications of these functional ingredients. We infer that there is a need for further human/clinical studies and evaluation, despite their health benefits. Additionally, the safety issues need to be adequately clarified and assessed, in order to establish a conventional therapeutic profile.

New Functionalized Polymeric Sensor Based NiO/MgO Nanocomposite for Potentiometric Determination of Doxorubicin Hydrochloride in Commercial Injections and Human Plasma

The ultra-functional potential of nickel oxide (NiO) and magnesium oxide (MgO) nanoparticles (NPs), provides for extensive attention in the use of these metal oxides as a remarkable and electroactive nanocomposite in potentiometric and sensing investigations. This work proposed a new strategy for quantifying doxorubicin hydrochloride (DOX) in pharmaceuticals and human plasma by preparing a NiO/MgO core-shell nanocomposite modified coated wire membrane sensor. Doxorubicin hydrochloride was incorporated with phosphomolybdic acid (PMA) to produce doxorubicin hydrochloride phosphomolybdate (DOX-PM) as an electroactive material in the presence of polymeric high molecular weight poly vinyl chloride (PVC) and solvent mediator o-nitrophenyloctyl ether (o-NPOE). The modified sensor exhibited ultra sensitivity and high selectivity for the detection and quantification of doxorubicin hydrochloride with a linear relationship in the range of 1.0 × 10-11-1.0 × 10-2 mol L-1. The equation of regression was estimated to be EmV = (57.86 ± 0.8) log [DOX] + 723.19. However, the conventional type DOX-PM showed a potential response over a concentration range of 1.0 × 10-6-1.0 × 10-2 mol L-1 and a regression equation of EmV = (52.92 ± 0.5) log [DOX] + 453.42. The suggested sensors were successfully used in the determination of doxorubicin hydrochloride in commercial injections and human plasma.