Spent coffee grounds as a suitable alternative to standard soil in ecotoxicological tests.

Eisenia andrei is considered in OECD and ISO guidelines to be a suitable replacement for Eisenia fetida in ecotoxicological assays. This suggests that other alternative materials and methods could also be used in standard procedures for toxicity testing. The guidelines also favor using less time-consuming procedures and reducing costs and other limitations to ecotoxicological assessments. In recent years, spent coffee grounds (SCG) have been used to produce vermicompost and biochar and as an additive to organic fertilizers. In addition, the physicochemical characteristics of SCG indicate that the material is a suitable substrate for earthworms, with the organisms performing as well as in natural soil. In the present study, a battery of ecotoxicological tests was established with unwashed and washed SCG and a natural reference soil (LUFA 2.2). The test substrates were spiked with different concentrations of silver nitrate. Survival and reproduction of the earthworm E. andrei were assessed under different conditions, along with substrate basal respiration (SBR) as a proxy for microbial activity. Seedling emergence and the germination index of Lepidium sativum were also determined, following standard guidelines. Exposure to silver nitrate had similar effects on earthworm survival and reproduction, as the estimated effective concentrations (EC10 and EC50) in unwashed SCG and LUFA 2.2 overlapped. A hormetic effect was observed for SBR in LUFA 2.2 spiked with 12.8 mg/kg but not in unwashed SCG. Both SBR and root development were inhibited by similar concentrations of silver nitrate in washed SCG. The findings indicate that unwashed SCG could potentially be used as a substrate in E. andrei toxicity tests and support the eventual inclusion of this material in the standard guidelines.

Eco-friendly approaches of zinc oxide and silver nitrate nanoparticles along with plant extracts against Spodoptera litura (Fabricius) under laboratory conditions.

The tobacco cutworm (Spodoptera litura) is a widespread pest that inflicts severe damage on various crops, including cotton, tobacco, and vegetables, with a particular preference for solanaceous plants. Traditional control methods often rely heavily on synthetic insecticides, leading to adverse effects on the environment, human health, and the development of insecticide resistance. In light of these challenges, this study explores the potential of nanotechnology as an innovative and sustainable approach to combat this notorious pest. Bioassays were conducted using laboratory-reared 3rd instar S. litura larvae. Eight different plant extracts coated with zinc oxide and silver nitrate nanoparticles were tested, with concentrations in both distilled water and ethanol at 3, 5, and 7 ml. Data were collected at 24, 48, and 72-h intervals. The results revealed that the highest larval mortality, reaching 98%, was observed in the group treated with silver nitrate nanoparticles derived from Cymbopogon citratus. In comparison, the group treated with zinc oxide nanoparticles dissolved in ethanol exhibited a larval mortality rate of 90%. Ethanol is a polar solvent that is widely used in the synthesis of nanocomposites. It is capable of forming strong hydrogen bonds with oxygen atoms, making it a good dispersant for zinc oxide nanoparticles. Additionally, ethanol has a low boiling point and a non-toxic nature, which makes it a safe and effective option for the dispersion of nanoparticles. Notably, the study concluded that silver nanoparticles combined with ethanol exhibited prolonged and more potent toxic effects against S. litura when compared to zinc oxide nanoparticles. Overall, this research underscores the potential of nanotechnology as a valuable component of Integrated Pest Management (IPM) strategies. By integrating nanotechnology into pest management practices, we can promote sustainable and environmentally friendly approaches that benefit both farmers and the ecosystem.

Biological properties of experimental dental alginate modified for self-disinfection using green nanotechnology.

OBJECTIVES: Disinfection of alginate impression materials is a mandatory step to prevent cross-infection in dental clinics. However, alginate disinfection methods are time-consuming and exert a negative impact on accuracy and mechanical properties. Thus, this study aimed to prepare disinfecting agents (CHX and AgNO3) and silver nanoparticles reduced by a natural plant extract to produce a self-disinfecting dental alginate. METHODS: Conventional alginate impression material was used in this study. Silver nitrate (0.2% AgNO3 group) and chlorohexidine (0.2% CHX group) solutions were prepared using distilled water, and these solutions were later employed for alginate preparation. Moreover, a 90% aqueous plant extract was prepared from Boswellia sacra (BS) oleoresin and used to reduce silver nitrate to form silver nanoparticles that were incorporated in the dental alginate preparation (BS+AgNPs group). The plant extract was characterized by gas chromatography/mass spectrometry (GC/MS) analysis while green-synthesized silver nanoparticles (AgNPs) were characterized by UV-visible (UV-vis) spectroscopy and scanning electron microscopy (SEM). An agar disc diffusion assay was used to test the antimicrobial activity against Candida albicans, Streptococcus mutans, Escherichia coli, methicillin-resistant and susceptible Staphylococcus aureus strains, and Micrococcus luteus. Agar plates were incubated at 37 ± 1 °C for 24 h to allow microbial growth. Diameters of the circular inhibition zones formed around each specimen were measured digitally by using ImageJ software. RESULTS: Chemical analysis of the plant extract revealed the presence of 41 volatile and semi-volatile active compounds. UV-Vis spectrophotometry, SEM, and EDX confirmed the formation of spherical silver nanoparticles using the BS extract. CHX, AgNO3, and the BS+AgNPs modified groups showed significantly larger inhibition zones than the control group against all tested strains. BS+AgNPs and CHX groups showed comparable efficacy against all tested strains except for Staphylococcus aureus, where the CHX-modified alginate had a significantly higher effect. CONCLUSIONS AND CLINICAL RELEVANCE: CHX, silver nitrate, and biosynthesized silver nanoparticles could be promising inexpensive potential candidates for the preparation of a self-disinfecting alginate impression material without affecting its performance. Green synthesis of metal nanoparticles using Boswellia sacra extract could be a very safe, efficient, and nontoxic way with the additional advantage of a synergistic action between metal ions and the phytotherapeutic agents of the plant extract.

Synthesis and Characterization of Silver Nanoparticles from Rhizophora apiculata and Studies on Their Wound Healing, Antioxidant, Anti-Inflammatory, and Cytotoxic Activity.

Silver nanoparticles (AgNPs) have recently gained interest in the medical field because of their biological features. The present study aimed at screening Rhizophora apiculata secondary metabolites, quantifying their flavonoids and total phenolics content, green synthesis and characterization of R. apiculata silver nanoparticles. In addition, an assessment of in vitro cytotoxic, antioxidant, anti-inflammatory and wound healing activity of R. apiculata and its synthesized AgNPs was carried out. The powdered plant material (leaves) was subjected to Soxhlet extraction to obtain R. apiculata aqueous extract. The R. apiculata extract was used as a reducing agent in synthesizing AgNPs from silver nitrate. The synthesized AgNPs were characterized by UV-Vis, SEM-EDX, XRD, FTIR, particle size analyzer and zeta potential. Further aqueous leaf extract of R. apiculata and AgNPs was subjected for in vitro antioxidant, anti-inflammatory, wound healing and cytotoxic activity against A375 (Skin cancer), A549 (Lung cancer), and KB-3-1 (Oral cancer) cell lines. All experiments were repeated three times (n = 3), and the results were given as the mean ± SEM. The flavonoids and total phenolics content in R. apiculata extract were 44.18 ± 0.086 mg/g of quercetin and 53.24 ± 0.028 mg/g of gallic acid, respectively. SEM analysis revealed R. apiculata AgNPs with diameters ranging from 35 to 100 nm. XRD confirmed that the synthesized silver nanoparticles were crystalline in nature. The cytotoxicity cell viability assay revealed that the AgNPs were less toxic (IC50 105.5 µg/mL) compared to the R. apiculata extract (IC50 47.47 µg/mL) against the non-cancerous fibroblast L929 cell line. Antioxidant, anti-inflammatory, and cytotoxicity tests revealed that AgNPs had significantly more activity than the plant extract. The AgNPs inhibited protein denaturation by a mean percentage of 71.65%, which was equivalent to the standard anti-inflammatory medication diclofenac (94.24%). The AgNPs showed considerable cytotoxic effect, and the percentage of cell viability against skin cancer, lung cancer, and oral cancer cell lines was 31.84%, 56.09% and 22.59%, respectively. R. apiculata AgNPs demonstrated stronger cell migration and percentage of wound closure (82.79%) compared to the plant extract (75.23%). The overall results revealed that R. apiculata AgNPs exhibited potential antioxidant, anti-inflammatory, wound healing, and cytotoxic properties. In future, R. apiculata should be further explored to unmask its therapeutic potential and the mechanistic pathways of AgNPs should be studied in detail in in vivo animal models.

Anti-plasmodial activity of aqueous neem leaf extract mediated green synthesis-based silver nitrate nanoparticles.

The objective of this study is to synthesize neem-silver nitrate nanoparticles (neem-AgNPs) using aqueous extracts of Azadirachta indica A. Juss for malaria therapy. Neem leaves collected from FRIM Malaysia were authenticated and extracted using Soxhlet extraction method. The extract was introduced to 1 mM of silver nitrate solution for neem-AgNPs synthesis. Synthesized AgNPs were further characterized by ultraviolet-visible spectroscopy and the electron-scanning microscopy. Meanwhile, for the anti-plasmodial activity of the neem-AgNPs, two lab-adapted Plasmodium falciparum strains, 3D7 (chloroquine-sensitive), and W2 (chloroquine-resistant) were tested. Red blood cells hemolysis was monitored to observe the effects of neem-AgNPs on normal and parasitized red blood cells. The synthesized neem-AgNPs were spherical in shape and showed a diameter range from 31-43 nm. When compared to aqueous neem leaves extract, the half inhibitory concentration (IC50) of the synthesized neem-AgNPs showed a four-fold IC50 decrease against both parasite strains with IC50 value of 40.920 µg/mL to 8.815 µg/mL for 3D7, and IC50 value of 98.770 µg/mL to 23.110 µg/mL on W2 strain. The hemolysis assay indicates that the synthesized neem-AgNPs and aqueous extract alone do not have hemolysis activity against normal and parasitized red blood cells. Therefore, this study shows the synthesized neem-AgNPs has a great potential to be used for malaria therapy.

Exploring the Antibacterial and Antibiofilm Efficacy of Silver Nanoparticles Biosynthesized Using Punica granatum Leaves.

The current research work illustrates an economical and rapid approach towards the biogenic synthesis of silver nanoparticles using aqueous Punica granatum leaves extract (PGL-AgNPs). The optimization of major parameters involved in the biosynthesis process was done using Box-Behnken Design (BBD). The effects of different independent variables (parameters), namely concentration of AgNO3, temperature and ratio of extract to AgNO3, on response viz. particle size and polydispersity index were analyzed. As a result of experiment designing, 17 reactions were generated, which were further validated experimentally. The statistical and mathematical approaches were employed on these reactions in order to interpret the relationship between the factors and responses. The biosynthesized nanoparticles were initially characterized by UV-vis spectrophotometry followed by physicochemical analysis for determination of particle size, polydispersity index and zeta potential via dynamic light scattering (DLS), SEM and EDX studies. Moreover, the determination of the functional group present in the leaves extract and PGL-AgNPs was done by FTIR. Antibacterial and antibiofilm efficacies of PGL-AgNPs against Gram-positive and Gram-negative bacteria were further determined. The physicochemical studies suggested that PGL-AgNPs were round in shape and of ~37.5 nm in size with uniform distribution. Our studies suggested that PGL-AgNPs exhibit potent antibacterial and antibiofilm properties.

Comparison of the antidepressant like activity of homeopathic remedies (Argentum nitricum, Staphysagria and Ignatia amara) and their effect on the behavior of rodents.

The majority of the world population suffers from mental and behavioral disorder. It is the need of the time to find an alternate of presently available medicines in order to decrease the medical expense. Homeopathic remedies are available and prescribed by homeopaths for treatment of anxiety and depression. Unfortunately, no data are available that proves its potential to relieve mental illness. The current study is designed to assess neuro behavioral and antidepressant like effects of homeopathic remedies Staphysagria, Argentum nitricum and Ignatia amara in comparison with standard drug (escitalopram). Different neuro behavioral activities were analyzed. The animals were administered the doses of all homeopathic remedied (60 µl to the rats) and escitalopram (0.042 mg to rats) through the oral route. The activities were observed on day 30th and day 60th. Our result suggests that the swimming time in Staphysagria treated group were significantly improved (p<0.001) after day 60th and significance rise was observed (p<0.01) in Ignatia amara treated animals, whereas significant decline (p<0.05) in struggling time was observed in Argentum nitricum administered animals after the 60th day as compared to 30th day. The central square crossings were improved highly significantly (p<0.001) after the 30th day dosing, by all three remedies and peripheral squares crossing were found highly significantly increased (p<0.001) after chronic dosing in Staphysagria and Ignatia amara treated groups. It is concluded from the results that all three homeopathic remedies produce comparable effects like standard drug while among all three remedies Staphysagria possess a potent antidepressant activity. To the best of our knowledge the current study reports first time the anti-depressant potential of homeopathic remedies in rodents.

Elicitor-Induced Production of Biomass and Pharmaceutical Phenolic Compounds in Cell Suspension Culture of Date Palm (Phoenix dactylifera L.).

Plants that synthesize bioactive compounds that have high antioxidant value and elicitation offer a reliable in vitro technique to produce important nutraceutical compounds. The objective of this study is to promote the biosynthesis of these phenolic compounds on a large scale using elicitors in date palm cell suspension culture. Elicitors such as pectin, yeast extract (YE), salicylic acid (SA), cadmium chloride (CdCl2), and silver nitrate (AgNO3) at 50, 100, and 200 mg/L concentrations are used. The effects of elicitors on cell culture were determined in terms of biomass [packed cell volume (PCV), fresh and dry weight], antioxidant activity, and phenolic compounds (catechin, caffeic acid, kaempferol, apigenin) were determined using high-performance liquid chromatography (HPLC). Results revealed that enhanced PCV (12.3%), total phenolic content [317.9 ± 28.7 mg gallic acid equivalents (GAE)/100 g of dry weight (DW)], and radical scavenging activity (86.0 ± 4.5%) were obtained in the 50 mg/L SA treated cell culture of Murashige and Skoog (MS) medium. The accumulation of optimum catechin (26.6 ± 1.3 µg/g DW), caffeic acid (31.4 ± 3.8 µg/g DW), and kaempferol (13.6 ± 1.6 µg/g DW) was found in the 50 mg/L SA-treated culture when compared to the control. These outcomes could be of great importance in the nutraceutical and agronomic industries.

Production of ascorbic acid, total protein, callus and root in vitro of non-heading Chinese cabbage by tissue culture.

The objective of the present work was the selection of cultivar, suitable medium and explant type for callus, root production, ascorbic acid, total ascorbic acid, dehydroascorbic and total protein of non-heading Chinese cabbage in two cultivars 'Caixin' and 'Suzhouqing'. We compared 10 types of MS media supplemented with 0.0, 1.0, 2.0 and 3.0 mg/l TDZ; 0.0, 0.25, 0.50 and 1.0 mg/l NAA and 0.0, 5.0, 7.5 and 9.0 mg/l AgNO3 and 5 kinds of explants as embryo, leaf, root, cotyledon and hypocotyl. Maximum frequency of callus fresh weight was recorded with hypocotyl explant, which were cultured on MS + 2.0 mg/l TDZ + 1.0 mg/l NAA + 9.0 mg/l AgNO3 in 'Suzhouqing', optimum callus dry weight was obtained on the same media. The highest result for root fresh and dry weight recorded with 'Caixin' with MS + 3.0 mg/l TDZ + 1.0 mg/l NAA + 9.0 mg/l AgNO3 when we used embryo as explant. The highest ascorbic acid content was found with callus cultured on MS + 1.0 mg/l TDZ + 0.25 mg/l NAA + 5.0 mg/l AgNO3, when used leaf explant in 'Caixin' or root in 'Suzhouqing', and there were no significant difference between them. While the highest value of total AsA content was registered with callus cultured on MS + 2.0 mg/l TDZ + 0.25 mg/l NAA + 5.0 mg/l AgNO3 extracted from cotyledon in 'Caixin'. The highest content of DHA was registered with MS + 2.0 mg/l TDZ + 0.25 mg/l NAA + 5.0 mg/l AgNO3 with cotyledon in 'Caixin'. Also, in 'Caixin' MS + 3.0 mg/l TDZ + 0.25 mg/l NAA + 5.0 mg/l AgNO3 recorded the highest value of total protein content with embryo explant.

Green synthesis of silver nanoparticles using Indian Belladonna extract and their potential antioxidant, anti-inflammatory, anticancer and larvicidal activities.

KEY MESSAGE: Atropa acuminata aqueous leaf extract biosynthesized silver nanoparticles showed strong antioxidant, anticancerous (HeLa cells) and anti-inflammatory activities. Besides, this bio syn-AgNP also proved effective against mosquito vectors causing malaria, dengue and filariasis. Present study highlights eco-friendly and sustainable approach for the synthesis of silver nanoparticles (AgNP) using aqueous leaf extract of A. acuminata, a critically endangered medicinal herb. The addition of 1 mM silver nitrate to aqueous leaf extract resulted in the synthesis of AgNP when solution was heated at 60 °C for 30 min at pH 7. Absorption band at 428 nm, as shown by UV-Vis spectroscopy confirmed the synthesis of AgNP. XRD patterns revealed the crystalline nature of AgNP and TEM analysis showed that most of the nanoparticles were spherical in shape. Zeta potential of AgNP was found to be - 33.5 mV which confirmed their high stability. FT-IR investigations confirmed the presence of different functional groups involved in the reduction and capping of AgNP. The synthesized AgNP showed effective DPPH (IC50-16.08 µg/mL), H2O2 (IC50-25.40 µg/mL), and superoxide (IC50-21.12 µg/mL) radical scavenging activities. These plant-AgNP showed significant inhibition of albumin denaturation (IC50-12.98 µg/mL) and antiproteinase activity (IC50-18.401 µg/mL). Besides, biosynthesized AgNP were found to have strong inhibitory effect against a cervical cancer (HeLa) cell line (IC50-5.418 µg/mL) as well as larvicidal activity against 3rd instar larvae of Anopheles stephensi (LC50-18.9 ppm, LC90-40.18 ppm), Aedes aegypti (LC50-12.395 ppm, LC90-36.34 ppm) and Culex quinquefasciatus (LC50-17.76 ppm, LC90-30.82 ppm) and were found to be non-toxic against normal cell line (HEK 293), and a non-target organism (Mesocyclops thermocyclopoides). This is the first report on the synthesis of AgNP using aqueous leaf extract of A. acuminata, validating their strong therapeutic potential.

In vitro evaluation of the protoscolicidal effect of Eucalyptus globulus essential oil on protoscolices of hydatid cyst compared with hypertonic saline, povidone iodine and silver nitrate.

OBJECTIVE: There are various protoscolicidal agents for inactivation of protoscoleces of hydatid cysts before and during surgical operation. The present study was aimed to evaluate the protoscolicidal effect of two concentrations of Eucalyptus globulus on protoscoleces of Echinococcus granulosus sensu lato under in vitro condition and to compare its efficacy with hypertonic saline, povidone iodine and silver nitrate. METHODS: Live protoscoleces obtained from the liver of naturally infected sheep were exposed to 0.5% and 1% of Eucalyptus globulus essential oil, 5% hypertonic saline, 10% povidone iodine and 0.5% silver nitrate for 1 and 3minutes. Phosphate buffered saline was used as a negative control. One percent eosin staining method was used to test the viability of protoscoleces in different groups. RESULTS: While the mean percentage of dead protoscoleces was 6.08% in the control group, the scolicidal power of 5% hypertonic saline was only 6.54% and 6.60% after 1 and 3min respectively. 0.5% E. globulus EO demonstrated 97.38% and 100% scolicidal activity after 1 and 3min respectively. The mean protoscolicidal power of 1% E. globulus EO, 10% povidone iodine and 0.5% silver nitrate was 100% after one minute. CONCLUSIONS: According to the results of this study, E. globulus EO demonstrated high scolicidal power in a short period of time. Hence, this herbal product could be considered as a potent natural scolicidal agent that could be used before and during surgery of hydatid disease.

Preparation, characterization and evaluation of the zinc titanate and silver nitrate incorporated wipes for topical chemical and biological decontamination.

Chemical and biological warfare agents have detrimental effects on biological systems. These agents are rapidly absorbed through skin and hence warrant immediate decontamination. Zinc titanate (ZnTiO3), is a well-proven moiety used for neutralizing chemical warfare agents (CWA) and silver is widely used as an antibacterial agent. Spacer fabric sheet, due to its ability to hold large amount of agents, was hydrothermally treated with silver nitrate (AgNO3) and incorporated with nano ZnTiO3 to prepare decontamination (deconwipes). Prepared deconwipe was characterized using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). Uniform deposition of nano ZnTiO3 and AgNO3 in the wipe was demonstrated by SEM and XRD. In-vivo dermal decontamination efficacy of the prepared deconwipe was evaluated against nerve agent simulant (diethylchlorophosphate; DCP) and sulfur mustard simulant (2­chloroethyl ethyl sulfide; CEES) on rat model using SEM, Flow Cytometry, Comet Acetylcholinesterase (AChE) inhibition assay and Organ Histopathology. In-vitro antibacterial and antifungal efficacy of the prepared deconwipe was evaluated using growth inhibitory efficacy techniques followed by SEM analysis. SEM and histopathology at dermal level revealed the decontamination efficacy of the prepared deconwipe. Nearly 90% decrease in AChE inhibition was observed in decontaminated rat in place of rate model as compared to the DCP contaminated rats. No significant attenuation was observed in DCP and CEES-induced cell cycle distribution and DNA damage analysis in decontaminated group. Furthermore, >95% inhibition of bacterial and fungal growth, proved its antibacterial and antifungal activity respectively. Thus, prepared deconwipes exhibit promising skin decontamination property against Chemical and biological contaminants.

Impact of Antioxidants on in vitro Rooting and Acclimatization of Two Egyptian Dry Date Palm Cultivars.

BACKGROUND AND OBJECTIVES: Date palm (Phoenix dactylifera L.) is propagated vegetatively via offshoots, which is limited by either the offshoots numbers produced from a superior selected plant, or the occurrence of these offshoots only during the juvenile phase of the date palm life cycle. As a result, the in vitro propagation could be considered an alternative technique for large scale propagation of date palm. Obtaining well-developed root system is considered the most important step in establishment of reliable protocol for successful production of date palm and subsequently successful acclimatization of the in vitro derived plants. The aim of this study is to obtain a well-developed root system through using different antioxidants, with detecting the similarity between the in vitro derived plants and the mother plants using RAPD, long RAPD and ISSR techniques. MATERIALS AND METHODS: Individual plantlets obtained from maturation of somatic embryos in vitro of about 5-7 cm in length with 2-3 leaves were used as plant material. Plantlets were cultured on half strength MS liquid medium supplemented with 0.5 mg L-1 thiamine-HCl+2.0 mg L-1 glycine+0.1 mg L-1 biotin+40 g L-1 sucrose+ 0.1mg L-1 NAA with different concentrations from either AgNO3 or citric or ascorbic acids (0.0, 0.5, 1, 2 mg L-1). Growth development, root number and root length (cm) were evaluated at the end of the second subculture (12 weeks). Data were reported as Mean±Standard deviation (SD). Data were subjected to one way-analysis of variance (p<0.05). Results were processed by Excel (2010). RESULTS: Among the different antioxidants with different concentrations used, generally it was found that 2 mg L-1 of each agent gave the highest values of growth development, roots number and roots length. However, using 2 mg L-1 AgNO3 gave the best results with all parameters. Regarding the response of date palm cultivar, it was remarkable that Bartamoda showed relatively better results than Sakkoty cultivar. According to PCR reactions, the results of RAPD, long RAPD and ISSR profile of tissue culture-derived plantlets grown on a medium supplemented with 2 mg L-1 AgNO3 obviously revealed high similarity to mother plants. CONCLUSION: It could be concluded that using 2 mg L-1 AgNO3 gave the best results for growth development, root numbers and length of the two cultivars but Bartamoda showed relatively better results than Sakkoty cultivar. The tissue culture-derived plantlets on this medium (2 mg L-1 AgNO3) revealed high similarity to mother plant as a result to RAPD, long RAPD and ISSR profiles.

Unravelling the effects of blue light on aerobic methane emissions from canola.

It is now well documented that plants produce methane (CH4) under aerobic conditions. However, the nature of methane production in plants and all the potential precursors and environmental factors that can be involved in the process are not fully understood. Earlier studies have suggested several chemical compounds, including the amino acid methionine, as precursors of aerobic methane in plants, but none have explored other amino acids as potential precursors or blue light as a driving force of methane emission. We examined the effects of blue light, and the promoter or inhibitor of endogenous ethylene on methane and ethylene emissions, amino acids, and some plant physiological parameters in canola (Brassica napus). Plants were grown under four light conditions: no supplemental blue light, and low, medium, or high blue light, and exposed to three chemical treatments: no chemical application, ethylene promoter (kinetin), or ethylene inhibitor (silver nitrate). Regardless of chemical treatment, blue light significantly increased methane emission, which was accompanied by decreased plant biomass, gas exchange, and flavonoids, but by increased wax, and most amino acids. This study revealed that blue light drives aerobic methane emission from plants by releasing of methyl group from a number of amino acids, and that the methane production in plants may have several pathways.

Beneficial effects of dietary silver nanoparticles and silver nitrate on broiler nutrition.

This study was conducted to investigate the growth modulatory effects of dietary supplementation with silver nanoparticles (Ag NPs) and Ag nitrate on broiler chickens. Thirty 15-day-old chicks were equally divided into the control group (fed basal diets), the Ag-nano group (fed basal diets supplemented with 50 ppm/kg of Ag NPs for 12 d), and the Ag nitrate group (fed basal diets supplemented with 100 ppm/kg Ag nitrate for 12 days). Chicks fed Ag NPs showed increased body weight gain and muscle weight, improved feed efficiency, and increased ash digestibility, while Ag digestibility tend to increase but not significant. Plasma triiodothyronine contents, and muscle Ag and nitrogen contents as well as a significant increase in the following mRNA levels in muscle tissue: insulin-like growth factor-1 (IGF1), glucose transporters (Glut1, Glut3), citrate synthase (CS), and glutathione peroxidase (GPx), whereas the atrogin-1, fatty acid synthase (FAS), acetyl CoA carboxylase (ACC), lactate dehydrogenase (LDH), and carnitine palmitoyl transferase 1A (CPT1A) mRNA levels were unchanged. However, these chicks exhibited decreased levels of plasma cholesterol, triglyceride, and glucose. Dietary supplementation with Ag NPs improved the growth performance of broiler chickens.

Antimicrobial Activity of a Colloidal AgNP Suspension Demonstrated In Vitro against Monoculture Biofilms: Toward a Novel Tooth Disinfectant for Treating Dental Caries.

A novel silver nanoparticle (AgNP) formulation was developed as a targeted application for the disinfection of carious dentine. Silver nitrate (AgNO3) was chemically reduced using sodium borohydrate (NaBH4) in the presence of sodium dodecyl sulfate (SDS) to form micelle aggregate structures containing monodisperse 6.7- to 9.2-nm stabilized AgNPs. AgNPs were characterized by measurement of electrical conductivity and dynamic light scattering, scanning electron microscopy, transmission electron microscopy, and inductively coupled plasma mass spectrometry. Antimicrobial activity of AgNPs was tested against planktonic cultures of representative gram-positive and gram-negative oral bacteria using well diffusion assays on tryptic soy broth media and monoculture biofilms grown with brain heart infusion ± sucrose anaerobically at 37°C on microtiter plates. Biofilm mass was measured by crystal violet assay. Effects were compared to silver diamine fluoride and chlorhexidine (negative controls) and 70% isopropanol (positive control) exposed cultures. In the presence of AgNPs, triplicate testing against Streptococcus gordonii DL1, C219, G102, and ATCC10558 strains; Streptococcus mutans UA159; Streptococcus mitis I18; and Enterococcus faecalis JH22 for planktonic bacteria, the minimum inhibitory concentrations were as low as 7.6 µg mL-1 and the minimum bacteriocidal concentrations as low as 19.2 µg mL-1 silver concentration. Microplate readings detecting crystal violet light absorption at 590 nm showed statistically significant differences between AgNP-exposed biofilms and where no antimicrobial agents were used. The presence of sucrose did not influence the sensitivity of any of the bacteria. By preventing in vitro biofilm formation for several Streptococcus spp. and E. faecalis, this AgNP formulation demonstrates potential for clinical application inhibiting biofilms.

Silver nanoparticles synthesized and coated with pectin: An ideal compromise for anti-bacterial and anti-biofilm action combined with wound-healing properties.

The synthesis of Ag nanoparticles from Ag+ has been investigated, with pectin acting both as reductant and coating.∼100% Ag+ to Ag(0) one-pot conversion was obtained, yielding p-AgNP, i.e. an aqueous solution of pectin-coated spherical Ag nanoparticles (d=8.0±2.6nm), with a<1ppm concentration of free Ag+ cation. Despite the low free Ag+ concentration and low Ag+ release with time, the nature of the coating allows p-AgNP to exert excellent antibacterial and antibiofilm actions, comparable to those of ionic silver, tested on E. coli (Gram-) and S. epidermidis (Gram+) both on planctonic cells and on pre- and post-biofilm formation conditions. Moreover, p-AgNP were tested on fibroblasts: not only p-AgNP were found to be cytocompatible but also revealed capable of promoting fibroblasts proliferation and to be effective for wound healing on model cultures. The antibacterial activity and the wound healing ability of silver nanoparticles are two apparently irreconcilable properties, as the former usually requires a high sustained Ag+ release while the latter requires low Ag+ concentration. p-AgNP represents an excellent compromise between opposite requirements, candidating as an efficient medication for repairing wounds and/or to treat vulnerable surgical site tissues, including the pre-treatment of implants as an effective prophylaxis in implant surgery.

Synthesis, characterization, and antimicrobial properties of novel double layer nanocomposite electrospun fibers for wound dressing applications.

Herein, novel hybrid nanomaterials were developed for wound dressing applications with antimicrobial properties. Electrospinning was used to fabricate a double layer nanocomposite nanofibrous mat consisting of an upper layer of poly(vinyl alcohol) and chitosan loaded with silver nanoparticles (AgNPs) and a lower layer of polyethylene oxide (PEO) or polyvinylpyrrolidone (PVP) nanofibers loaded with chlorhexidine (as an antiseptic). The top layer containing AgNPs, whose purpose was to protect the wound site against environmental germ invasion, was prepared by reducing silver nitrate to its nanoparticulate form through interaction with chitosan. The lower layer, which would be in direct contact with the injured site, contained the antibiotic drug needed to avoid wound infections which would otherwise interfere with the healing process. Initially, the upper layer was electrospun, followed sequentially by electrospinning the second layer, creating a bilayer nanofibrous mat. The morphology of the nanofibrous mats was studied by scanning electron microscopy and transmission electron microscopy, showing successful nanofiber production. X-ray diffraction confirmed the reduction of silver nitrate to AgNPs. Fourier transform infrared spectroscopy showed a successful incorporation of the material used in the produced nanofibrous mats. Thermal studies carried out by thermogravimetric analysis indicated that the PVP-drug-loaded layer had the highest thermal stability in comparison to other fabricated nanofibrous mats. Antimicrobial activities of the as-synthesized nanofibrous mats against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans were determined using disk diffusion method. The results indicated that the PEO-drug-loaded mat had the highest antibacterial activity, warranting further attention for numerous wound-healing applications.

Synergistic effect of silver nitrate and coconut water on shoot differentiation and plant regeneration from cultured cotyledons of Capsicum annuum L.

Chili pepper (Capsicum annuum L.) ranks among the most important vegetable crop belonging to the family Solanaceae that is consumed both as vegetable and spice throughout the world. C. annuum, as crop, in order to meet the target yield, demands improved variety that could overcome environmental challenges viz., biotic and abiotic stress. Cultivar improvement essentially requires an efficient in vitro regeneration protocol. In the present study, we investigated the influence of silver nitrate (AgNO3) and coconut water, individually as well in combination, on in vitro shoot elongation and plant regeneration from cotyledon explants of C. annuum cv G-4. Shoot buds were induced on shoot bud induction medium supplemented with either 44.38 µM 6-benzylaminopurine (BAP) or 9.0 µM thidiazuron (TDZ) along with 5.77 µM gibberellic acid (GA3) and 14.7 µM phenyl acetic acid (PAA). Elongation of shoot buds was obtained on elongation medium containing 8.87 µM BA or 0.45 µM TDZ, 5.77 µM GA3 and 14.7 µM PAA followed by rooting in 9.8 µM indole-3-butyric acid (IBA). All the media were supplemented with 30 µM AgNO3 and/or coconut water (10% v/v). The presence of coconut water in the elongation media enhanced the regeneration of well developed shoots from differentiating explants on TDZ media while AgNO3 resulted in enhanced production of rooted shoots with greater influence on emerging shoots from BAP media upon transfer to rooting media. There was synergistic response with further enhancement of elongated shoots/elongated rooted shoots on the combined use of coconut water and AgNO3. The elongation media produced significantly higher total shoots when AgNO3 was used synergistically with coconut water (59.0%) as against AgNO3 alone (38.0%). While in rooting media, there was significantly higher production of elongated rooted shoots when coconut water was used synergistically with AgNO3 (47.2%) as against the coconut water alone (14.4%).

New antibacterial, non-genotoxic materials, derived from the functionalization of the anti-thyroid drug methimazole with silver ions.

The new silver(I) compound {[AgBr(µ2-S-MMI)(TPP))]2} (1) and the known one [AgCl(TPP)2(MMI)] (2) were obtained by refluxing toluene solutions of silver(I) halide with triphenylphosphine (TPP) and the anti-thyroid drug 2-mercapto-1-methyl-imidazole or methimazole (MMI). The complexes were characterized by m.p., vibrational spectroscopy (mid-FT-IR), (1)H, (31)P-NMR, UV-Vis spectroscopic techniques and X-ray crystallography. The antibacterial effect of 1 and 2 against the bacterial species Pseudomonas aeruginosa (PAO) and Escherichia coli was evaluated. Compound 1 exhibits comparable activity to the corresponding one of the silver nitrate which is an antibacterial drug in use. The in vivo genotoxicity of 1-2 by the mean of Allium cepa test shows no alterations in the mitotic index values due to the absence of chromosomal aberrations. The mechanism of action of the title compounds is evaluated. The DNA binding tests indicate the ability of the complexes 1-2 to modify the activity of the bacteria. The binding constants of 1-2 towards CT-DNA indicate interaction through opening of the hydrogen bonds of DNA. Docking studies on DNA-complexes interactions confirm the binding of both complexes 1-2 in the major groove of the CT-DNA. In conclusion the silver complex 1 is an anti-bacterial and non-genotoxic material, which can be applied to antibacterial drug in the future.