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Scientific studies have demonstrated that the vegetable material extracts act as potential precursors for the synthesis of nanomaterial using eco-friendly ways. Because the plant extracts contain various secondary metabolites, they act as reducing and stabilizing agents for the bioreduction reaction for synthesis of novel metallic nanoparticles.Herein, we describe the characteristics of different algae types, from different locations (Belgium and South Correa). Algae have important components, like chlorophyll and other plant pigments, omega-3 fatty acids and essential elements. Also, it has been demonstrated that algae provide a rich source of natural bioactive compounds with antibacterial and antioxidant properties. Another important aspect is the fact that algae represent a good wastewater treatment. In addition to the economic aspect, algae biomass is a source of biodiesel and offers an efficient way for nutrient consumption and provides aerobic bacteria with oxygen through photosynthesis. It is a low-cost technique for the removal of phosphorus, nitrogen and pathogens. We first characterized and compared quantitatively (polyphenols, flavonoids) and qualitatively (carbohydrates, alkaloids) the properties of two algae types extracts (green algae - Enteromorpha spp. and brown ones - Hizikia fusiforme). We then obtained and characterized the gold nanoparticles, formed using HAuCl4 (10-3 M) and algae sample extracts. The algae extracts, the green method for obtaining metallic nanoparticles (AuNP) and the nanoparticles investigated by UV-Vis spectroscopy, optical microscopy and SEM technique are shown in this research.

The present research describes the components of the ivy (Hedera helix L.) plant extract. It is known that ivy presents a lot of health benefits, like antibacterial, antimicrobial, anticancer properties or skin care, due to their components. So, the aim of our study was to characterize quantitative (polyphenols, tannins, flavonoids, terpenoids) and qualitative (saponins, proteins, steroids) screening for phytochemical compounds and antioxidant activity of the hydroalcoholic extract obtained by ivy leaves. The sample was analyzed by UV-VIS, FTIR, TLC techniques. The antioxidant activity was evaluated using DPPH method. The antimicrobial activity was demonstrated on bacteria, yeast and mold species.

Phytosynthesis can certainly be considered next generation’s technology that enables the development of novel nanoparticles and nanomaterials with various applications in multidisciplinary scientific areas. Squash (Cucurbita maxima) is a fruit rich in beta-carotene, calcium, potassium and has numerous health benefits. This paper describes recent researches in the field of metallic nanoparticles, namely silver and gold, prepared via phytosynthesis from aqueous extracts of Waltham butternut squash. Silver and gold nanoparticles can be prepared using conventional routes that have numerous drawbacks. Phytosynthesis has multiple advantages: is cost effective, environmentally – friendly, doesn’t require high pressure and no hazardous chemicals are used. Aqueous extracts were prepared from different parts of Waltham butternut squash (e.g.: shell, core and seeds) and their phytochemical content was evaluated using standard qualitative and quantitative analyses. The metallic nanoparticles were phytosynthesized from the aqueous extracts and corresponding metallic salts using two different conditions: room temperature, no stirring, overnight and 500 C, under continuous stirring for 30 minutes. The phytosynthesized metallic nanoparticles were characterized by recording UV-Vis spectra at different time intervals in order to determine their stability in time. The characteristic absorptions maxima were recorded at 435 - 450 nm for silver nanoparticles and at 535 - 550 nm for gold nanoparticles. The antioxidant activity was recorded using DPPH (2,2 – diphenyl – 1 – picryl – hydrazyl – hydrate) assay and the calculated values were clearly higher for the phytosynthesized metallic nanoparticles compared to the aqueous extracts.

Green chemistry is a state-of-the art method widely recognized as a useful tool for promoting and enabling sustainable development at both laboratory and industrial scale characterized by the use of environmentally friendly materials such as bacteria, fungi, and different plant species. Metallic nanoparticles exhibit attractive and unique properties due to their reduced size and morphology, which are the basis of development to a variety of useful applications, especially in nanotechnology, biotechnology, and nanomedicine. In the past decades, sustained work has been done to develop new eco-friendly methods for the preparation of well-characterized metallic nanoparticles. Green synthesis removes the limitation of the conventional chemical routes and allows the production of well-defined size and shape metallic nanoparticles with little to no toxicity to humans and environment. To date, hundreds of plant species from different parts of the world have been used for the green synthesis of metallic nanoparticles (with emphasis on silver and gold nanoparticles due to their known antibacterial and antimicrobial activity), with good to excellent results, and therefore, it represents an affordable route for large-scale production. This chapter focuses on the green synthesis of lanthanides- and actinides-based nanoparticles from vegetal materials (plants and plant parts), different microorganisms (bacteria, fungi, algae), or describes other environmentally friendly routes. The focus is on lanthanide oxide- and actinide oxide-based nanomaterials, such as cerium oxide (CeONPs), lanthanum oxide (LaONPs) and their perovskite-type nanoparticles (e.g., LaAlO3), yttrium oxide nanoparticles (Y2O3NPs), their preparation via green chemistry methods and details all the methods used to investigate and characterize the formation of the metallic nanoparticles, such as ultraviolet–visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and atomic force microscopy (AFM). Also, it details the antioxidant, antimicrobial, and antifungal activity of the aforementioned green-synthesized lanthanide- and actinide- based nanoparticles.

Pumpkin (Cucurbita maxima) is a fruit packed with vitamins and nutrients beneficial to human health with numerous therapeutic uses including antiparasitic, antioxidant, it helps to lower bad cholesterol, as an adjuvant in weight loss, improves cancer prevention, etc. Pumpkin is rich in beta-carotene, and contains significant amounts of lutein and zeaxanthin, antioxidants that can considerably prevent cataracts and macular degeneration. Worldwide, five pumpkin species are grown for their edible fruit and seeds. This paper describes the qualitative screening of phytocompounds and the quantitative determination of the main bioactive compounds found in two pumpkin species: Valenciano and Waltham Butternut. The qualitative screening of phytochemicals was based on the visual change in color of aqueous extracts upon adding known reactants. This allowed a preliminary evaluation regarding the presence of different bioactive compounds such as saponins, alkaloids, tannins, flavonoids, etc. In order to determine the specific amount of different phytocompounds (e.g., total content of polyphenols, total content of flavonoids, etc.) UV-Vis spectra were recorded in triplicate at well-established wavelengths, thus obtaining an average absorbance. For example, a method widely applied for the determination of total polyphenolic content is the Folin–Ciocalteu (FC) reaction, which is basically an antioxidant analyses that relies on electron transfer that measures the reductive ability of a specific antioxidant. Briefly, the FC reaction involved mixing 1 mL diluted aqueous extract with 5 mL FC reagent and adding 4 mL Na2CO3 after 8 min After 60 min incubation at room temperature, we recorded the absorptions at 765 nm, which corresponds to the gallic acid curve calibration standard. Also, the antioxidant activity was recorded by using the DPPH method for both aqueous extracts.

The present research describes the components of two types of medicinal plants. [...]

Hydroxyapatite is mainly used in biomedical applications because of its very important property—bioactivity. [...]

Noble metallic nanoparticles, silver (AgNPs) and gold (AuNPs) mainly, exhibit good antimicrobial, antibacterial and antifungal properties and, therefore, have a significant contribution to the constant - growing field of nanomedicine. They can be synthesized using both conventional or unconventional methods and, in the last decades especially, the unconventional routes that use plants as raw vegetal materials are studied with proven results. On the other hand, macrocyclic derivatives such as phthalocyanines (Pcs) have photoactive properties and numerous applications. The conjugation between silver and gold nanoparticles with phthalocyanine derivatives considerable increases both the photochemical activity of Pcs as well as the stability of noble metallic nanoparticles. This paper describes recent researches in the field of green synthesized AgNPs and AuNPs from different plants with important pharmacological applications in two different temperature conditions: at room temperature, for 12 hours and at 500 C for 30 minutes. AgNPs and AuNPs then react with tetracarboxamido-zinc phthalocyanine ZnPc(CONH2)4 and octacarboxamido–zinc phthalocyanine ZnPc(CONH2)8 to obtain two hybrid nanoaggregates, confirmed by spectroscopic analyzes (e.g.: UV-Vis, FTIR, DLS, SEM, TEM, XRD) and by determining their antioxidant and antimicrobial activity.

The aim of this study was to assess the properties of some concrete samples according to their [...]

Stone monuments represent a big part of the world’s cultural heritage. [...]

As the development of the textile industry has progressed, intense concerns have been focusedon the contamination of the environment caused by dye pollutants [...]

Silver nanoparticles, widely known for their antimicrobial, antioxidant, and antifungal properties, can be obtained using conventional or unconventional methods and have various applications in different scientific fields, including degradation of dyes from the textile industry [1,2]. [...]

The article presents experimental data regarding some organic compounds as chemical intermediates with phthalic acid structure, precursors for new phthalocyanine compounds as : 4-nitrophthalimide, 4-aminophthalimide, 4-nitrophthalonitrile and 4-aminophthalonitrile, synthesized by chemical transformation of phthalimide by a series of successive reactions as : nitration and reduction, or nitration, amidation, dehydration and reduction. Reaction products were purified and characterized by means of elemental analysis, UV-Vis, fluorescence, IR, 1H-NMR, 13C-NMR spectroscopy, and thermal analysis. Structure-property relationship in the organic compounds is discussed with respect to the nature of the substituents.