Green synthesis, antibacterial, antioxidant and cytotoxic effect of gold nanoparticles using Pistacia Atlantica extract

Electrospun nanofibers synthesized from polymers incorporated with bioactive compounds for wound healing

The development of innovative wound dressing materials is crucial for effective wound care. It's an active area of research driven by a better understanding of chronic wound pathogenesis. Addressing wound care properly is a clinical challenge, but there is a growing demand for advancements in this field. The synergy of medicinal plants and nanotechnology offers a promising approach to expedite the healing process for both acute and chronic wounds by facilitating the appropriate progression through various healing phases. Metal nanoparticles play an increasingly pivotal role in promoting efficient wound healing and preventing secondary bacterial infections. Their small size and high surface area facilitate enhanced biological interaction and penetration at the wound site. Specifically designed for topical drug delivery, these nanoparticles enable the sustained release of therapeutic molecules, such as growth factors and antibiotics. This targeted approach ensures optimal cell-to-cell interactions, proliferation, and vascularization, fostering effective and controlled wound healing. Nanoscale scaffolds have significant attention due to their attractive properties, including delivery capacity, high porosity and high surface area. They mimic the Extracellular matrix (ECM) and hence biocompatible. In response to the alarming rise of antibiotic-resistant, biohybrid nanofibrous wound dressings are gradually replacing conventional antibiotic delivery systems. This emerging class of wound dressings comprises biopolymeric nanofibers with inherent antibacterial properties, nature-derived compounds, and biofunctional agents. Nanotechnology, diminutive nanomaterials, nanoscaffolds, nanofibers, and biomaterials are harnessed for targeted drug delivery aimed at wound healing. This review article discusses the effects of nanofibrous scaffolds loaded with nanoparticles on wound healing, including biological (in vivo and in vitro) and mechanical outcomes.

Nutraceutical Content and Biological Properties of Lipophilic and Hydrophilic Fractions of the Phytocomplex from Pistacia atlantica Desf. Buds, Roots, and Fruits

The aim of the present investigation was to obtain 12 aqueous extracts and 1 oil from Pistacia atlantica Desf. subsp. atlantica specimens. The samples differed for processed plant organs (i.e., roots, buds, and fruits), gender and geographical station of the collected trees. Total phenols, flavonoids, and condensed tannins were determined, revealing that bud extracts exhibited the highest phenolic content (386.785 ± 16.227 mg GAE/g DM), followed by fruit and root preparations. Similar results were detected for flavonoids and tannins, whose quantitation ranged from 0.014 ± 0.005 to 74.780 ± 9.724 mg CE/g DM and from 0.037 ± 0.003 to 14.793 ± 0.821 mg CE/g DM, respectively. The biochemical profile of the extracts was further characterized by HPLC-DAD, in terms of specific phenolics. This analysis identified gallic acid as a typical metabolite for ripe fruit, while hydroxytyrosol for female roots and male buds. In parallel, P. atlantica fruit oil was profiled by GC-MS analysis, which detected 37 lipophilic components, including palmitic acid (the major component, ~55%), anacardol, tetradecanol, arachidic acid, squalene, and some terpenes. The samples revealed interesting antioxidant activity, with EC50 values ranging from 0.073 ± 0.001 to 193.594 ± 28.942 mg/mL and from 0.029 ± 0.001 to 103.086 ± 20.540 mg/mL, in that order, for DPPH and reducing power assays. Concerning the total antioxidant capacity, the results ranged from 0.053 ± 0.008 to 51.648 ± 1.659 mg AAE/g DM. Finally, the antimicrobial potential of the plant extracts was estimated against 7 bacterial species and 2 fungal strains, known to be human pathogens, demonstrating a good antibiotic effect for the bud extracts. All these findings strongly suggest that P. atlantica would represent a natural reservoir for novel additives to be used in therapeutic, food, and cosmetic products.

A comprehensive review on antibacterial analysis of natural extract-based metal and metal oxide nanoparticles

Pharmaceutical, food packing, cosmetics, agriculture, energy storage devices widely utilize metal and metal oxide nanoparticles prepared via different physical and chemical methods. It resulted in the release of several dangerous compounds and solvents as the nanoparticles were being formed. Currently, Researchers interested in preparing nanoparticles (NPs) via biological approach due to their unique physiochemical properties which took part in reducing the environmental risks. However, a number of microbial species are causing dangerous illnesses and are a threat to the entire planet. The metal and metal oxide nanoparticles played a significant role in the identification and elimination of microbes when prepared using natural extract. Its biological performance is thus also becoming exponentially more apparent than it was using in conventional techniques. Despite the fact that they hurt germs, their small size and well-defined shape encourage surface contact with them. The generation of Reactive Oxygen Species (ROS), weakens the bacterial cell membrane by allowing internal cellular components to seep out. The bacterium dies as a result of this. Numerous studies on different nanoparticles and their antibacterial efficacy against various diseases are still accessible. The main objective of the biogenic research on the synthesis of key metals and metal oxides (such as gold, silver, titanium dioxide, nickel oxide, and zinc oxide) using various plant extracts is reviewed in this study along with the process of nanoparticle formation and the importance of phytochemicals found in the plant extract.

Calotropis procera (L.) mediated synthesis of AgNPs and their application to control leaf spot of Hibiscus rosa-sinensis (L.)

Abstract Nature is gifted with a wide range of ornamental plants, which beautify and clean the nature. Due to its great aesthetic value, there is a need to protect these plants from a variety of biotic and abiotic stresses. Hibiscus rosa-sinensis (L.) is an ornamental plant and it is commonly known as China rose or shoeblack plant. It is affected by several fungal and bacterial pathogens. Current study was designed to isolate leaf spot pathogen of H. rosa-sinensis and its control using silver nanoparticles (AgNPs). Based on molecular and morphological features, the isolated leaf spot pathogen was identified as Aspergillus niger. AgNPs were synthesized in the leaf extract of Calotropis procera and characterized. UV-vis spectral analysis displayed discrete plasmon resonance bands on the surface of synthesized AgNPs, depicting the presence of aromatic amino acids. Fourier transform infrared spectroscopy (FTIR) described the presence of C-O, NH, C-H, and O-H functional groups, which act as stabilizing and reducing molecules. X-ray diffraction (XRD) revealed the average size (~32.43 nm) of AgNPs and scanning electron microscopy (SEM) depicted their spherical nature. In this study, in vitro and in vivo antifungal activity of AgNPs was investigated. In vitro antifungal activity analysis revealed the highest growth inhibition of mycelia (87%) at 1.0 mg/ml concentration of AgNPs. The same concentration of AgNPs tremendously inhibited the spread of disease on infected leaves of H. rosa-sinensis. These results demonstrated significant disease control ability of AgNPs and suggested their use on different ornamental plants.

Green synthesis of Au@g-C3N4 nanocomposite using Hyssopus officinalis extract and its sensing application for vortioxetine determination

Herein, we introduce a stable and green Au@g-C3N4 nanocomposite as a selective electrochemical sensor for vortioxetine (VOR) determination. The electrochemical behavior of VOR on the developed electrode was investigated through cyclic voltammetry (CV), differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS), and chronoamperometry. The Au@g-C3N4 nanocomposite was thoroughly observed by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, and scanning electron microscopy. The Au@g-C3N4 nanocomposite had a higher conductivity and a narrower band gap than pure g-C3N4, causing higher electrochemical activity for VOR detection. Moreover, Au@g-C3N4 on the glassy carbon electrode (Au@g-C3N4/GCE) monitored a low level of VOR with high efficiency and low interference as an environmentally friendly processing approach. Interestingly, the as-fabricated sensor exhibited an ultrahigh selectivity for recognizing VOR with a detection limit (LOD) of 3.2 nM. Furthermore, the developed sensor was applied to determine VOR in pharmaceutical and biological samples, which indicated a high selectivity in the presence of interferences. This study suggests new insights into the phytosynthesis synthesis of nanomaterials with excellent biosensing applications.

Biosynthesis of Nanoparticles Using Plant Extracts and Essential Oils

Plant extracts and essential oils have a wide variety of molecules with potential application in different fields such as medicine, the food industry, and cosmetics. Furthermore, these plant derivatives are widely interested in human and animal health, including potent antitumor, antifungal, anti-inflammatory, and bactericidal activity. Given this diversity, different methodologies were needed to optimize the extraction, purification, and characterization of each class of biomolecules. In addition, these plant products can still be used in the synthesis of nanomaterials to reduce the undesirable effects of conventional synthesis routes based on hazardous/toxic chemical reagents and associate the properties of nanomaterials with those present in extracts and essential oils. Vegetable oils and extracts are chemically complex, and although they are already used in the synthesis of nanomaterials, limited studies have examined which molecules are effectively acting in the synthesis and stabilization of these nanostructures. Similarly, few studies have investigated whether the molecules coating the nanomaterials derived from these extracts and essential oils would bring benefits or somehow reduce their potential activity. This synergistic effect presents a promising field to be further explored. Thus, in this review article, we conducted a comprehensive review addressing the main groups of molecules present in plant extracts and essential oils, their extraction capacity, and available methodologies for their characterization. Moreover, we highlighted the potential of these plant products in the synthesis of different metallic nanomaterials and their antimicrobial capacity. Furthermore, we correlated the extract’s role in antimicrobial activity, considering the potential synergy between molecules from the plant product and the different metallic forms associated with nanomaterials.

Design and synthesis of Ag NPs/chitosan-starch nano-biocomposite as a modern anti-human malignant melanoma drug

In recent years, the unprecedented increase in various cancers such as melanoma has caused researchers to focus more on the formulation of newer drugs with less side effects. In this study, we herein indicate the biogenic nanoarchitechtonics of Ag NPs template over chitosan/starch mixed hydrogel having notable reducing potential and anti-malignant melanoma effects. The two biopolymers also could stabilize as-synthesized Ag NPs. Physicochemical features of the material were further characterized over a range of advanced methods like X-ray diffraction (XRD), elemental mapping, dynamic light scattering (DLS), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), and Fourier transformed infrared spectroscopy (FT-IR). TEM analysis showed the spherical-shaped nanocomposite with the mean diameter in the range of 5-15 nm. Thereafter, the nanocomposite was exploited in the anti-malignant melanoma and cytotoxicity effects studies against various human malignant melanoma cell lines (HT144, RPMI7951, SKMEL2, UACC3074, WM266-4 and MUM2C) in situ. The bio-composite corresponding IC₅₀ values were 193, 102, 227, 250, 301, and 203 μg/mL against MUM2C, WM266-4, UACC3074, SKMEL2, RPMI7951, and HT144 cell lines, respectively. A significantly high IC₅₀ value offered an excellent antioxidant capacity of bio-composite. According to the above results, Ag NPs/CS-Starch nanomaterial can be utilized as an efficient drug to treat malignant melanoma in humans after doing clinical trial studies.

Synthesis and Characterization of Eugenia uniflora L. Silver Nanoparticles and L-Cysteine Sensor Application

L-Cysteine (Cys) is a non-essential sulfur-containing amino acid, crucial for protein synthesis, detoxification, and several metabolic functions. Cys is widely used in the agricultural, food, cosmetic, and pharmaceutical industries. So, a suitable sensitive and selective sensing approach is of great interest, and a low-cost sensor would be necessary. This article presents silver nanoparticles (EuAgNPs) synthesized by a green synthesis method using Eugenia uniflora L. extracts and photoreduction. The nanoparticles were characterized by UV/VIS, transmission electron microscopy, high-performance liquid chromatography (HPLC), FTIR, and Zeta potential. With the addition of Cys in the EuAgNPs solution, the terminal thiol part of L-cysteine binds on the surface of nanoparticles through Ag-S bond. The EuAgNPs and CysAgNPs coexist until flavonoids bound the amino group of Cys, enhancing the red color of solutions. The EuAgNPs provided selectivity to detect Cys among other amino acids, and its detection limit was found to be 3.8 nM. The sensor has the advantages of low-cost synthesis, fast response, high selectivity, and sensitivity.

Antimicrobial Activity of Silver and Gold Nanoparticles Prepared by Photoreduction Process with Leaves and Fruit Extracts of Plinia cauliflora and Punica granatum

The increased number of resistant microbes generates a search for new antibiotic methods. Metallic nanoparticles have emerged as a new platform against several microorganisms. The nanoparticles can damage the bacteria membrane and DNA by oxidative stress. The photoreduction process is a clean and low-cost method for obtaining silver and gold nanoparticles. This work describes two original insights: (1) the use of extracts of leaves and fruits from a Brazilian plant Plinia cauliflora, compared with a well know plant Punica granatum, and (2) the use of phytochemicals as stabilizing agents in the photoreduction process. The prepared nanoparticles were characterized by UV-vis, FTIR, transmission electron microscopy, and Zeta potential. The antimicrobial activity of nanoparticles was obtained with Gram-negative and Gram-positive bacteria, particularly the pathogens Staphylococcus aureus ATCC 25923; Bacillus subtilis ATCC 6633; clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and Enterococcus faecalis; Escherichia coli ATCC 25922; Escherichia coli O44:H18 EAEC042 (clinical isolate); Klebsiella pneumoniae ATCC 700603, Salmonella Thiphymurium ATCC 10231; Pseudomonas aeruginosa ATCC 27853; and Candida albicans ATCC 10231. Excellent synthesis results were obtained. The AgNPs exhibited antimicrobial activities against Gram-negative and Gram-positive bacteria and yeast (80–100%), better than AuNPs (0–87.92%), and may have the potential to be used as antimicrobial agents.

Green synthesis of ionic liquid mediated neodymium oxide nanoparticles via Couroupita guianensis abul leaves extract with its biological applications

Bio-nanoparticles have created a new era of rapid, harmless and nontoxic drugs for various biomedical applications. The nanoparticles (NPs) of rare earth metal oxides attract researcher's attention due to their excellent chemical and physical properties that exhibit potential activity against disease causing pathogens. Couroupita guianensis (C. guianensis) abul is a medicinal plant whose leaves are effectively used for the synthesis of neodymium oxide (Nd₂O₃) NPs. The 1-butyl 3-methyl imidazolium tetrafluoroborate (BMIM BF₄) ionic liquid is used as a stabilizing agent to get better the morphology and biological properties of Nd₂O₃ NPs. 1-Butene, 4,4-diethoxy-2-methyl is the main compound in C. guianensis abul leaves extract was confirmed by GCMS analysis. The structure of synthesized Nd₂O₃ (without ionic liquid) and Nd₂O₃-IL (with ionic liquid) NPs is identified by powder X-ray diffraction (PXRD). The vibrations of the different functional groups were investigated by Fourier-transform infrared (FTIR) and Raman spectroscopy. In UV-Vis spectra, the optical absorption was identified to be 210 and 221nm of Nd₂O₃ and Nd₂O₃-IL samples and the PL spectrum provides blue and green emission peaks at 386 and 554 nm. The X-ray photoelectron spectroscopy (XPS) and DLS spectra illustrate the electronic configuration and particle size of the synthesized Nd₂O₃-IL NPs. The morphology, surface nature and lattice spacing were analyzed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The purity and weight percentage of the compound presented can be identified by the energy-dispersive X-ray spectroscopy (EDX). The biomedical properties such as antibacterial, antioxidant, antidiabetic, anti-inflammatory and anticancer activities were investigated. Finally, the overall biocompatible studies reveal that the ionic liquid assisted Nd₂O₃ NPs can be considered as a potential drug for pharmaceutical and biomedical applications.

Green Metallic Nanoparticles: Biosynthesis to Applications

Current advancements in nanotechnology and nanoscience have resulted in new nanomaterials, which may pose health and environmental risks. Furthermore, several researchers are working to optimize ecologically friendly procedures for creating metal and metal oxide nanoparticles. The primary goal is to decrease the adverse effects of synthetic processes, their accompanying chemicals, and the resulting complexes. Utilizing various biomaterials for nanoparticle preparation is a beneficial approach in green nanotechnology. Furthermore, using the biological qualities of nature through a variety of activities is an excellent way to achieve this goal. Algae, plants, bacteria, and fungus have been employed to make energy-efficient, low-cost, and nontoxic metallic nanoparticles in the last few decades. Despite the environmental advantages of using green chemistry-based biological synthesis over traditional methods as discussed in this article, there are some unresolved issues such as particle size and shape consistency, reproducibility of the synthesis process, and understanding of the mechanisms involved in producing metallic nanoparticles via biological entities. Consequently, there is a need for further research to analyze and comprehend the real biological synthesis-dependent processes. This is currently an untapped hot research topic that required more investment to properly leverage the green manufacturing of metallic nanoparticles through living entities. The review covers such green methods of synthesizing nanoparticles and their utilization in the scientific world.

Catalytic and Medical Potential of a Phyto-Functionalized Reduced Graphene Oxide-Gold Nanocomposite Using Willow-Leaved Knotgrass

In the current study, a simple, environmentally friendly, and cost-effective reduced graphene oxide-gold nanoparticle (rGO-AuNP) nanocomposite was successfully phytosynthesized using the aqueous leaf extract of a common weed found on the Nile banks, Persicaria salicifolia, for the first time. The phytosynthesis of rGO-AuNPs was first confirmed via the color transformation from brown to black as well as throughvarious techniques such as transmission electron microscopy (TEM) and Raman spectroscopy. Two UV-vis peaks at 275 and 530 nm were observed for the nanocomposite with a typical particle size of mostly spherical AuNPs of 15-20 nm. However, other shapes were occasionally detected including rods, triangles, and rhomboids. Existing phytoconstituents such as flavonoids and glycosides in the plant extract were suggested to be responsible for the phytosynthesis of rGO-AuNPs. The excellent catalytic efficacy of rGO-AuNPs against MB degradation was confirmed, and a high antibacterial efficiency against Escherichia coli and Klebsiella pneumonia was also confirmed. Promising antioxidant performance of rGO-AuNPs was also proved. Furthermore, it was concluded that rGO-AuNPs acquired higher efficiency than AuNPs synthesized from the same plant extract in all of the studied applications.

Gold Nanoparticles: Biosynthesis and Potential of Biomedical Application

Gold nanoparticles (AuNPs) are extremely promising objects for solving a wide range of biomedical problems. The gold nanoparticles production by biological method ("green synthesis") is eco-friendly and allows minimization of the amount of harmful chemical and toxic byproducts. This review is devoted to the AuNPs biosynthesis peculiarities using various living organisms (bacteria, fungi, algae, and plants). The participation of various biomolecules in the AuNPs synthesis and the influence of size, shapes, and capping agents on the functionalities are described. The proposed action mechanisms on target cells are highlighted. The biological activities of "green" AuNPs (antimicrobial, anticancer, antiviral, etc.) and the possibilities of their further biomedical application are also discussed.

Bioavailability and antioxidant activity of nanotechnology-based botanic antioxidants

Botanic bioactive substances have issues with their solubility, stability, and oral bioavailability in the application, which could be improved by nanotechnologies. In another hands, green synthesis of nanoparticles (NPs) with plant extract is also a promising technology for preparation of NPs due to its safety advantage, yet the bioactive botanic substances that could be more than the assistant of the green synthesis of NPs. Based on the above concerns, this review summarized the preparation of botanic NPs with various plant extract, their solubility, stability, and oral bioavailability; specific attention has been paid to the botanic Ag/Au NPs, their capacity of antioxidant, bioavailability, antimicrobial, anti-inflammatory, and anticancer.

Critical analysis of biophysicochemical parameters for qualitative improvement of phytogenic nanoparticles

Conventional chemical approaches for synthesizing nanoparticles (NPs) may restrict their applicability as they are not eco-friendly, energetically efficient and often involve toxic reducing/capping agents; but phytonanotechnology enabled the synthesis of safe, inexpensive, highly biocompatible NPs. In this regard, thorough understanding of green components and the modulatory effects of different reaction conditions on the physicochemical parameters of green synthesized NPs would be a prerequisite, which is not depicted elsewhere. This review critically analyzes the relevant reaction conditions from their mechanistic viewpoints in plant-based synthesis of NPs arising fundamental issues which need to be determined carefully. The size, stability and surface chemistry of phytogenic NPs may be fabricated as a function of multiple interconnected reaction parameters and the plant species used. The therapeutic potential of phytogenic NPs may depend on the plant species used; and so the meticulous understanding of physicochemical parameters and the family wise shorting of elite plant species may potentially benefit the theranostic future of plant-based NPs.

Bactericidal Antibacterial Mechanism of Plant Synthesized Silver, Gold and Bimetallic Nanoparticles

As the field of nanomedicine develops and tackles the recent surge in antibiotic resistance, there is a need to have an in-depth understanding and a synergistic view of research on the effectiveness of a metal nanoparticle (NP) as an antibacterial agent especially their mechanisms of action. The constant development of bacterial resistance has led scientists to develop novel antibiotic agents. Silver, gold and its bimetallic combination are one of the most promising metal NPs because they show strong antibacterial activity. In this review we discuss the mode of synthesis and the proposed mechanism of biocidal antibacterial activity of metal NPs. These mechanisms include DNA degradation, protein oxidation, generation of reactive oxygen species, lipid peroxidation, ATP depletion, damage of biomolecules and membrane interaction.

Decorated Au NPs on agar modified Fe3O4 NPs: Investigation of its catalytic performance in the degradation of methylene orange, and anti-human breast carcinoma properties

This work describes an eco-friendly approach for in situ immobilization of Au nanoparticles on the surface of Fe₃O₄ nanoparticles, with help of Agar and ultrasound irradiations, without using any toxic reducing and capping agents. The structure, morphology, and physicochemical properties were characterized by various analytical techniques such as Fourier transformed infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), inductively coupled plasma (ICP) and vibrating sample magnetometer (VSM). The desired catalyst showed great efficiency in the reductive degradation of methylene orange (MO) dye over NaBH₄ at room temperature. The MO was fully reduced in only 70 s and achieved rate constant of 9.6 × 10^-2 s^-1. The catalyst was reused for 10 runs without significant loss in catalytic activity. Cell viability of Fe₃O₄/agar/Au NPs was very low against breast adenocarcinoma (MCF7), breast carcinoma (Hs 578Bst), infiltrating ductal cell carcinoma (Hs 319.T), and metastatic carcinoma (MDA-MB-453) cell lines without any cytotoxicity on the normal cell line. According to the above findings, the Fe₃O₄/agar/Au NPs may be administrated for the treatment of several types of human breast carcinoma in humans.

Immunostimulant and biocompatible gold and silver nanoparticles synthesized using the Ulva intestinalis L. aqueous extract

This is the first study to report on the biocompatible and immunogenic properties of one-pot synthesised gold and silver nanoparticles (Au@UI and Ag@UI) using the macroalgae Ulva intestinalis (UI). The UI aqueous extract, Au@UI, and Ag@UI were obtained under sterile conditions and fully characterized by UV-vis spectroscopy, TEM, HRTEM, STEM and FTIR spectroscopy. Moreover, for the first time, the composition of carbohydrates in the UI extract has been reported along with the changes observed after nanoparticle synthesis by size exclusion chromatography, in order to investigate their possible role in the biosynthetic process. This study suggested that the polysaccharide fraction of the extract is involved in the formation and stabilization of the nanoparticles. The potential toxicity of the samples was evaluated using different cell lines and the hemocompatibility was tested in mouse erythrocytes. In addition, ROS production, complement activation and cytokine release were evaluated to determine the immunogenicity. The results showed that Au@UI and Ag@UI exhibit good biocompatibility and hemocompatibility, with the exception of Ag@UI nanoparticles at high concentration, which were hemolytic. The samples induced ROS release and complement activation, two key mechanisms in innate immunity. The samples also induced the release of cytokines from Th1 and Th2 profiles, and other cytokines implicated in the activation of the immune system. Au@UI and Ag@UI were biocompatible and preserved the immunostimulant properties of the UI extract. Hence, Au@UI and Ag@UI could be useful as adjuvants in vaccine development and promote a balanced Th1 and Th2 immune response mediated by ROS production, cytokine release and complement activation.

Antioxidant Graphene Oxide Nanoribbon as a Novel Whitening Agent Inhibits Microphthalmia-Associated Transcription Factor-Related Melanogenesis Mechanism

In the melanin synthesis process, oxidative reactions play an essential role, and it is a good strategy to inhibit melanin production by reducing oxidative stress. Fullerene and its derivatives, or the complexes, were considered as strong free-radical scavengers, and we further applied multilayered sp² nanocarbons to discover melanin synthesis inhibitory mechanisms. In the present study, we used novel nanomaterials, such as multiwalled carbon nanotubes (MWCNTs), short-type MWCNTs, graphene oxide nanoribbons (GONRs), and short-type GONRs, as anti-oxidative agents to regulate melanin production. The results showed that GONRs had better anti-oxidative capabilities in intracellular and extracellular oxidative stress analysis platforms than others. We proposed that GONRs have oxygen-containing functional groups. In the 2',7'-dichlorodihydrofluorescein diacetate assay, we found out GONR could chelate metal ions to scavenge reactive oxygen species. In the molecular insight view, we observed that these nanomaterials downregulated the melanin synthesis by decreasing microphthalmia-associated transcription factor-related gene expressions, and there were similar consequences in protein expressions. To sum up, GONRs is a potential agent as a novel antioxidant and skin-whitening cosmetology material.

Pistacia Atlantica Desf., a Source of Healthy Vegetable Oil

Pistacia atlantica, which belongs to the Anacardiaceae family, is an important species for rural people in arid and semi-arid areas. The fruit, rich in oil, is used in traditional medicine for the treatment of various diseases. The oil extracted from this species growing in a northern area of Algeria and its fatty acid composition were previously studied. However, the largest areas where this species is present (traditional cultivation) is located in southern Algeria. Moreover, studies on oil fatty acid composition and essential oil were always conducted separately. This study was performed in order to assess the fatty acid and volatile organic compound composition of P. atlantica vegetable oil. The seeds were collected randomly from Djelfa (300 km South of Algiers, Algeria). Oil content and fatty acid composition were determined by Soxhlet extraction. The seeds contained high concentrations of oil (32–67%). The major fatty acids were oleic (39–49%), linoleic (23.6–31%), and palmitic (21.3–26.6%) acids. The ratio of polyunsaturated fatty acids (PUFA) to saturated fatty acids (SFA) indicated that the content of unsaturated fatty acids was approximately three times higher than that of SFA. This ratio is widely used in epidemiological studies and research on cardiovascular diseases, diabetes, and metabolic syndrome. The ratios of -acids, i.e., -9/-6 and -6/-3, were 1.3–2 and 18.5–38.3, respectively. Crushed seeds were analyzed by headspace solid-phase microextraction (SPME) coupled with gas chromatography–mass spectrometry. More than 40 compounds were identified, mainly monoterpenes (C10H16), such as α-terpinene and terpinolene, but also sesquiterpenes (C15H24) at lower levels. The value of this species as a source of healthy oil rich in -3 acid and its effects on cardiovascular disease risk are discussed.