Optimization of a DNA nicking assay to evaluate Oenocarpus bataua and Camellia sinensis antioxidant capacity

Molecular features, antioxidant potential, and immunological expression assessment of thioredoxin-like protein 1 (TXNL1) in yellowtail clownfish (Amphiprion clarkii)

Thioredoxin-like protein 1 (TXNL1) is a redox-active protein belonging to the thioredoxin family, which mainly controls the redox status of cells. The TXNL1 gene from Amphiprion clarkii (AcTXNL1) was obtained from a pre-established transcriptome database. The AcTXNL1 is encoded with 289 amino acids and is predominantly localized in the cytoplasm and nucleus. The TXN domain of AcTXNL1 comprises a34CGPC37 motif with redox-reactive thiol (SH-) groups. The spatial distribution pattern of AcTXNL1 mRNA was examined in different tissues, and the muscle was identified as the highest expressed tissue. AcTXNL1 mRNA levels in the blood and gills were significantly increased in response to different immunostimulants. In vitro antioxidant capacity of the recombinant AcTXNL1 protein (rACTXNL1) was evaluated using the ABTS free radical-scavenging activity assay, cupric ion reducing antioxidant capacity assay, turbidimetric disulfide reduction assay, and DNA nicking protection assay. The potent antioxidant activity of rAcTXNL1 exhibited a concentration-dependent manner in all assays. Furthermore, in the cellular environment, overexpression of AcTXNL1 increased cell viability under H2O2 stress and reduced nitric oxide (NO) production induced by lipopolysaccharides (LPS). Collectively, the experimental results revealed that AcTXNL1 is an antioxidant and immunologically important gene in A. clarkii.

Gold nanoparticles synthesis using Gymnosporia montana L. and its biological profile: a pioneer report

BACKGROUND

The forming, blending, and characterization of materials at a size of one billionth of a meter or less is referred to as nanotechnology. The objective of the current study was to synthesize ecologically friendly gold nanoparticles (AuNPs) from Gymnosporia montana L. (G. montana) leaf extract, characterize them, assess their interaction with different types of deoxyribonucleic acid (DNA), and investigate their antioxidant and toxic capabilities.

RESULTS

The biosynthesized AuNPs presence was validated by a color change from yellow to reddish pink as well as using UV-visible spectrophotometer. Fourier transform infrared (FTIR) spectroscopy analysis showed the presence of phytoconstituents like, alcohols, phenols, and nitro compounds responsible for the reduction of AuNPs. Zeta sizer and zeta potential of 559.6 d. nm and - 4.5 mV, respectively, demonstrated potential stability. With an average size between 10 and 50 nm, X-ray diffraction (XRD), and high-resolution transmission electron microscope (HR-TEM), revealed the crystalline formation of AuNPs. Surface topology with 3D characterization, irregular spherical shape, and size with 6.48 nm of AuNPs was determined with the help of an atomic force microscope (AFM). AuNPs with some irregular and spherical shapes, and sizes between 2 and 20 nm, were revealed by field emission scanning electron microscope (FESEM) investigation. Shifts in the spectrum were visible when the bioavailability of AuNPs with calf-thymus DNA (CT-DNA) and Herring sperm DNA (HS-DNA) was tested. Additionally, the DNA nicking assay's interaction with pBR322 DNA confirmed its physiochemical and antioxidant properties. The same was also found by using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, which showed a 70-80% inhibition rate. Finally, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay revealed that viability decreased with increasing dosage, going from 77.74 to 46.99% on MCF-7 cell line.

CONCLUSION

Synthesizing AuNPs through biogenic processes and adopting G. montana for the first time revealed potential DNA interaction, antioxidant, and cytotoxicity capabilities. Thus, opening new possibilities in the turf of therapeutics as well as in other areas.

Neuromodulatory effect of 4-(methylthio)butyl isothiocyanate against 3-nitropropionic acid induced oxidative impairments in human dopaminergic SH-SY5Y cells via BDNF/CREB/TrkB pathway

Mitochondrial impairment, energetic crisis and elevated oxidative stress have been demonstrated to play a pivotal role in the pathological processes of Huntington's disease (HD). 3-Nitropropionic acid (3-NPA) is a natural neurotoxin that mimics the neurological dysfunctions, mitochondrial impairments and oxidative imbalance of HD. The current investigation was undertaken to demonstrate the neuroprotective effect of 4-(methylthio)butyl isothiocyanate (4-MTBITC) against the 3-NPA induced neurotoxicity in human dopaminergic SH-SY5Y cells. The experimental evidence of oxidative DNA damage by 3-NPA was elucidated by pBR322 DNA nicking assay. In contrast, the 4-MTBITC considerably attenuated the DNA damage, suggesting its free radical scavenging action against 3-NPA and Fenton's reagent. The dose and time-dependent increase of 3-NPA revealed its neurotoxic dose as 0.5 mM after 24 h of treatment of SH-SY5Y cells in MTT assay. In order to determine the optimal dose at which 4-MTBITC protects cell death, the 3-NPA (IC₅₀) induced cells were pretreated with different concentrations of 4-MTBITC for 1 h. The neuroprotective dose of 4-MTBITC against 3-NPA was found to be 0.25 μM. Additionally, the elevated GSH levels in cells treated with 4-MTBITC indicate its propensity to eliminate reactive species generated as a result of 3-NPA-induced mitochondrial dysfunction. Likewise, it was determined through microscopic and flow cytometric experiments that 3-NPA's induced overproduction of reactive species and a decline in mitochondrial membrane potential (MMP) could be efficiently prevented by pre-treating cells with 4-MTBITC. To elucidate the underlying molecular mechanism, the RT-qPCR analysis revealed that the pre-treatment of 4-MTBITC effectively protected neuronal cells against 3-NPA-induced cell death by preventing Caspase-3 activation, Brain-derived neurotrophic factor (BDNF) upregulation, activation of cAMP response element-binding protein (CREB) and Nrf2 induction. Together, our findings lend credence to the idea that pre-treatment with 4-MTBITC reduced 3-NPA-induced neurotoxicity by lowering redox impairment, apoptotic state, and mitochondrial dysfunction. The present work, in conclusion, presented the first proof that the phytoconstituent 4-MTBITC supports the antioxidant system, BDNF/TrkB/CREB signaling, and neuronal survival in dopaminergic SH-SY5Y cells against 3-NPA-induced oxidative deficits.

Thioredoxin domain-containing protein 12 (TXNDC12) in red spotted grouper (Epinephelus akaara): Molecular characteristics, disulfide reductase activities, and immune responses

Thioredoxins are small ubiquitous redox proteins that are involved in many biological processes. Proteins with thiol-disulfide bonds are essential regulators of cellular redox homeostasis and diagnostic markers for redox-dependent diseases. Here, we identified and characterized the thioredoxin domain-containing protein 12 (EaTXNDC12) gene in red spotted grouper (Epinephelus akaara), evaluated transcriptional responses, and investigated the activity of the recombinant protein using functional assays. EaTXNDC12 is a 19.22-kDa endoplasmic reticulum (ER)-resident protein with a 522-bp open reading frame and 173 amino acids, including a signal peptide. We identified a conserved active motif (⁶⁶WCGAC⁷⁰) and ER retention motif (¹⁷⁰GDEL¹⁷³) in the EaTXNDC12 amino acid sequence. Relative EaTXNDC12 mRNA expression was analyzed using 12 different tissues, with the highest expression seen in brain tissue, while skin tissue showed the lowest expression level. Furthermore, mRNA expression in response to immune challenges was analyzed in the head kidney, blood, and gill tissues. EaTXNDC12 was significantly modulated in response to bacterial endotoxin lipopolysaccharide (LPS), nervous necrosis virus (NNV), and polyinosinic:polycytidylic acid (poly(I:C)) challenges in all of the tested tissues. Recombinant EaTXNDC12 (rEaTXNDC12) displayed antioxidant ability in an insulin reductase assay, and a capacity for free radical inhibition in a 2,2-diphenyl-1-picryl-hydrazyl-hydrate assay. In addition, a DNA nicking assay revealed that purified rEaTXNDC12 exhibited concentration-dependent DNA protection activity, while results from 2-hydroxyethyl disulfide and L-dehydroascorbic assays indicated that rEaTXNDC12a possesses reducing ability. Furthermore, fathead minnow (FHM) cells transfected with EaTXNDC12-pcDNA demonstrated significantly upregulated cell survival against H₂O₂-induced apoptosis. Collectively, the results of this study strengthen our knowledge of EaTXNDC12 with respect to cellular redox hemostasis and immune regulation in Epinephelus akaara.

Irradiation impact on biological activities of Anthraquinone pigment produced from Talaromyces purpureogenus and its evaluation, characterization and application in beef burger as natural preservative

BACKGROUND

The demand for natural coloring and preservative agents in food industry is increasing day by day as a result of awareness of the negative health effects of synthetic color preservatives. Consumers want foods with less processing, a longer shelf life, and clear labels that list only natural ingredients and food additives with familiar names that promote good health. In order to meet consumer demands and regain consumers' confidence in the safety of food products, the food industry was compelled to search for natural alternatives with strong antibacterial and antioxidant properties. Therefore, the objective of this study was to produce a microbial pigment that not only serve as food coloring agents but also provide health advantages owing to their bioactivities. Additionally, the potential use of anthraquinone pigment (AQP) as a natural food preservative compared to gamma irradiation was also examined to extend the shelf life of the beef burger and improve its hygienic quality.

RESULTS

This study used Talaromyces purpureogenus AUMC2603 to produce the red natural pigment, which was identified as an anthraquinone pigment (AQP). According to the results, gamma (γ) radiation had no significant effect on AQP's antibacterial properties. However, it has a negative, considerable effect on antioxidant activity, where a large dose of γ-ray may change the antioxidant components and lessen the AQP's capacity to scavenge free radicals. Additionally, the γ ray-treated AQP had a strong cytotoxic activity in relation to a high γ-ray dose. As a result, it is suggested that AQP-containing foods should not be irradiated. The extracted AQP was applied as a food additive to improve the quality and increase the shelf life of beef burgers. Significant antibacterial and antioxidant action has been shown at 2% (w/v) AQP. The findings demonstrated that the treatment of beef burger with AQP decreased the initial total bacterial count and psychrophilic bacteria and extended the shelf-life of beef burger in comparison to the control (beef burger with no addition of AQP, butylated hydroxytoluene (BHT) or gamma radiation treatment). On the other hand, there was no substantial difference in the overall amount of mold and yeast or coliform at zero time. According to sensory characteristics, beef burgers had a shelf life of 6 days for controls and 9, 12, and 15 days for AQP-treated samples at 0.5, 1 and 2%, respectively, compared to γ- irradiated samples, 9 and 21 days, at 3 and 5 Kilo Gray (KGy), respectively.

CONCLUSIONS

This research provides a natural red pigment from Talaromyces purpureogenus with potent biological activities as antimicrobials and antioxidants to be applied as coloring, additive, and preservative agent in the food industry. Also, the tested pigment offers a powerful alternative to gamma irradiation for extending the shelf life of food products.

Optimization, purification, and structure elucidation of Anthraquinone pigment derivative from Talaromyces purpureogenus as a novel promising antioxidant, anticancer, and kidney radio-imaging agentAnthraquinone pigment as a promising antioxidant, anticancer, and radio-imaging agent

This study aims to investigate the bioproduction and prospective biological applications of a natural red pigment from Talaromyces purpureogenus AUMC2603. Maximum pigment yield was achieved by a numerical optimization at pH 6, temperature 25°C, and an 18-day incubation period on Yeast Malt Broth (YMB) media. The crude pigment was separated and purified into two pigment fractions via solid-phase extraction and then characterized as anthraquinone (dominant) and herquinone by LC/MS and ¹HNMR analysis. The crude pigment extract and the two separated fractions displayed a potential antioxidant activity. Additionally, they showed a powerful anticancer activity towards cancer cell lines, MCF-7, HepG-2, and HCT116 with less cytotoxicity on normal cell lines, MCF12F and BJ-1T. The radioiodination efficiency of the radiosynthesized ^99mTc-anthraquinone pigment complex was also investigated and optimized, obtaining a radiochemical yield of 92.70% ± 0.89%. An in vivo biodistribution study of the ^99mTc-anthraquinone pigment complex demonstrated a high kidney uptake of 34% injected dose per gram of organ tissue 60min after intravenous injection, and the complex retention remained high up to 120min. The current study is the first bioassay report on the efficacy of a purified anthraquinone from T. purpureogenus as a potent agent for kidney radio-imaging that could be applied in kidney cancer diagnosis.

Nutraceutical potential of Amazonian oilseeds in modulating the immune system against COVID-19 - A narrative review

Since the outbreak of COVID-19 disease, medical and scientific communities are facing a challenge to contain its spread, develop effective treatments, and reduce its sequelae. Together with the therapeutical treatments, the use of dietary bioactive compounds represents a promising and cost-effective strategy to modulate immunological responses. Amazonian oilseeds are great sources of bioactive compounds, thus representing not only a dietary source of nutrients but also of substances with great interest for human health. This narrative review compiled the available evidence regarding the biochemical properties of some Amazonian oilseeds, especially Brazil nut, Açaí berry, Bacaba, Peach palm, Sapucaya and Tucuma fruits, on human health and its immune system. These effects were discussed from an etiological and pathophysiological perspective, emphasizing their potential role as a co-adjuvant strategy against COVID-19. Besides this, the cost associated with these strategies hinders their applicability in many nations, especially low-income countries and communities living in social insecurity.

Bio-Synthesis of Aspergillus terreus Mediated Gold Nanoparticle: Antimicrobial, Antioxidant, Antifungal and In Vitro Cytotoxicity Studies

Gold nanoparticles (GNP) were bio-fabricated utilizing the methanolic extract of the endophytic isolate Aspergillus terreus. The biosynthesised gold nanoparticles (GNP023) were characterised using UV-visible spectroscopy (UV-Vis); transmission electron microscopy (TEM), Fourier-transform nfrared spectroscopy (FTIR) and X-ray diffraction (XRD) studies. The bio-fabricated GNP023 displayed a sharp SPR peak at 536 nm, were spherically shaped, and had an average size between 10–16 nm. The EDX profile confirmed the presence of gold (Au), and XRD analysis confirmed the crystalline nature of GNP023. The antimicrobial activity of GNP023 was investigated against several food-borne and phytopathogens, using in vitro antibacterial and antifungal assays. The maximum zone of inhibition was observed for S. aureus and V. cholera at 400 μg /mL, whereas inhibition in radial mycelial growth was observed against Fusarium oxysporum and Rhizoctonia solani at 52.5% and 65.46%, respectively, when challenged with GNP023 (200 μg/mL). Moreover, the gold nanoparticles displayed significant antioxidant activity against the ABTS radical, with an IC₅₀ of 38.61 µg/mL, and were non-toxic when tested against human kidney embryonic 293 (HEK293) cells. Thus, the current work supports the application of myco-synthesised gold nanoparticles as a versatile antimicrobial candidate against food-borne pathogens.

Nano Milk Protein-Mucilage Complexes: Characterization and Anticancer Effect

The anticancer activity of natural compounds has recently attracted multidisciplinary research. In this study, the complexation of milk proteins (MP) with Isabgol husk mucilage (IHM) and Ziziphus spina-christi mucilage (NabM) was investigated. In this context, the physicochemical properties of milk protein mucilage complexes (MPMC) including pH, Carr's index, water solubility, and water absorption indices were measured, and the flow behavior was studied. In addition, the amino acid profile, protein digestibility, and phenolic and flavonoids content of MPMC were explored, and the microstructure of the complexes was visualized using transmission electron microscopy. The antioxidant and anticancer potencies of MPMC against two cancerous cell lines, human liver cancer HEPG-2 and breast cancer MCF-7, in comparison with two normal cell lines, namely, Bj-1 and MCF-12F, were tested using neutral red uptake assay. The results revealed that MPMC had scavenging activity against DPPH, ABTS, and HS radicals. Moreover, MPMC has the potential to prevent DNA damage induced by oxidative stress in Type-Fenton's reaction. The results of the neutral red assay showed significant growth inhibition of both HEPG-2, MCF-7, whereas no significant cytotoxic effect was detected against Bj-1 and MCF-12F. RT-qPCR results indicated MPMC stimulated apoptosis as revealed by the upregulation of the pro-apoptosis gene markers Casepase-3, p53, Bax. Meanwhile, the anti-apoptosis Bcl-2 gene was downregulated. However, no significant difference was observed in normal cell lines treated with MPMC. In conclusion, MPMC can be considered as a promising anticancer entity that can be used in the development of novel cancer therapeutics with comparable activity and minimal side effects compared to conventional cancer chemotherapies.

Anticarcinogenic and Antioxidant Action of an Edible Aquatic Flora Jussiaea repens L. Using In Vitro Bioassays and In Vivo Zebrafish Model

Oxidative stress is the major cause of many health conditions, and regular consumption of antioxidants helped to encounter and prevent such oxidative stress-related diseases. Due to safety concerns over long-term uses of synthetic antioxidants, natural antioxidants are more preferred. The purpose of this study is to investigate the antioxidant and anticancer activities of Jussiaea repens L., a wild edible flora found in Manipur, India. The antioxidant activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), Ferric reducing antioxidant power (FRAP) assay and DNA-nicking assay. The anticancer activity was tested using five cancer lines viz., SKOV3 cells (ovarian), HeLa (cervical), MDA-MB-231 (breast), PANC-1 (pancreatic), and PC3 (prostate). The toxicity, developmental effect, antiproliferative activity was further tested using zebrafish embryos. The methanolic plant extract had higher polyphenol content than flavonoids. The in vitro study demonstrated a promising antioxidant capacity and DNA protection ability of this plant. The extract also showed cytotoxic activity against SKOV3, HeLa, MDA-MB-23, and PANC-1 cancer cell lines. The in vivo studies on zebrafish embryos demonstrated the extract’s ability to suppress the developmental process and elicited more cytotoxicity to cancer cells than developing zebrafish embryos. Moreover, the in vivo studies on zebrafish embryos also indicated the antiproliferative activity of J. repens L. extract.

Valorization of chicken feather waste into bioactive keratin hydrolysate by a newly purified keratinase from Bacillus sp. RCM-SSR-102

The objective of this study is the characterization of a keratinase from Bacillus sp.RCM-SSR-102 and its application in the preparation of keratin hydrolysate from chicken feather waste. The purified KER102 keratinase was characterized as a serine-metallo protease having a molecular weight of 30 kDa with optimum pH and temperature of 10 and 50 °C respectively. The keratinase could retain 98% activity at pH 10 and above and 55% activity at 20% salt concentration. The KER102 keratinase was found to be stable in the presence of oxidizing agents, surfactants and organic solvents. The keratinase could also hydrolyze both soluble and insoluble complex protein substrates. The KER102 keratinase could hydrolyze up to 5% (w/v) feather releasing 1.7 ± 0.19 mg/mL soluble peptides. The feather keratin hydrolysate (FKH) had both antioxidant and antityrosinase activity. The IC₅₀ value of FKH in 2, 2-diphenyl 1-picrylhydrazyl (DPPH) radical scavenging activity (1.02 ± 0.01 mg/mL), 2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activity (20 ± +00.04 μg/mL) and anti-tyrosinase activity (1.2 ± 0.22 mg/mL) was recorded. The FKH also had DNA protecting ability against oxidative damage. Antioxidant and anti-tyrosinase compounds have potential applications in the pharmaceutical and cosmeceutical industry. Hence, the purified keratinase can be a potential candidate for the production of antioxidant and antityrosinase compounds from chicken feather waste.

Protective effect of Berberis vulgaris on Fenton reaction-induced DNA cleavage

OBJECTIVE

Berberis vulgaris contains antioxidants that can inhibit DNA cleavage. The purpose of this study was to evaluate the antioxidant and protective activity of B. vulgaris on DNA cleavage.

MATERIALS AND METHODS

In this study, the antioxidant capacity of B. vulgaris was investigated using DPPH and its protective effect was evaluated on pBR322 plasmid and lymphocyte genomic DNA cleavage induced by Fenton reaction, by DNA electrophoresis.

RESULTS

Aqueous extract of B. vulgaris presented dual behavior with a potent antioxidant activity at 0.25and 0.75mg/ml for pBR322 plasmid and lymphocyte genomic DNA, respectively, but a pro-oxidant activity was observed at higher concentrations.

CONCLUSION

Our results indicated that B. vulgaris extract an inhibit Fenton reaction-induced DNA cleavage and oxidative cleavage of double-stranded DNA assay is a powerful technique that can be used to determine the antioxidant and pro-oxidant properties of a compound on cellular components such as DNA.

Analysis of DNA protection, interaction and antimicrobial activity of isatin derivatives

Isatin, thiosemicarbazone and their derivatives have been widely used in biological applications such as antimicrobial, antiviral and anticancer therapies. Herein, eight isatin and thiosemicarbazone derivative compounds were re-synthesized and evaluated for DNA binding analysis including DNA protection studies using plasmid DNA (pUC19) and DNA interaction experiments using calf thymus DNA (CT-DNA). All compounds were also utilized in vitro assay to assess the antimicrobial activity of compounds against different pathogenic bacterial strains. All isatin and thiosemicarbazone derivative compounds exhibited DNA protection activity which ranged from 23.5 to 59.5%. Among them, I3-(N-2-MP)-TSC had the greatest DNA protective activity. For DNA binding analysis, all compounds had the same constant concentration (40 μM), which interacts with CT-DNA. It was also observed that DNA interactions gave a high intrinsic binding constant (Kb = 1.72 × 10⁴ M^-1-9.73 × 10⁵ M^-1). Besides, several derivatives of isatin thiosemicarbazone exhibited significant and selective antibacterial activity with low concentration. These compounds primarily affected Gram-positive bacteria, but were not effective against P. vulgaris and E. coli. The Gram-positive methicillin-resistant S. aureus ATCC 43300 (MRSA) was the most influenced strain by these compounds. It was found that methyphenyl group at isatin was essential for its antibacterial activity for MRSA.

Chemical Composition and Antioxidant Activity of Euterpe oleracea Roots and Leaflets

Euterpe oleracea (açaí) is a palm tree well known for the high antioxidant activity of its berries used as dietary supplements. Little is known about the biological activity and the composition of its vegetative organs. The objective of this study was to investigate the antioxidant activity of root and leaflet extracts of Euterpe oleracea (E. oleracea) and characterize their phytochemicals. E. oleracea roots and leaflets extracts were screened in different chemical antioxidant assays (DPPH—2,2-diphenyl-1-picrylhydrazyl, FRAP—ferric feducing antioxidant power, and ORAC—oxygen radical absorbance capacity), in a DNA nicking assay and in a cellular antioxidant activity assay. Their polyphenolic profiles were determined by UV and LC-MS/MS. E. oleracea leaflets had higher antioxidant activity than E. oleracea berries, and leaflets of Oenocarpus bacaba and Oenocarpus bataua, as well as similar antioxidant activity to green tea. E. oleracea leaflet extracts were more complex than root extracts, with fourteen compounds, including caffeoylquinic acids and C-glycosyl derivatives of apigenin and luteolin. In the roots, six caffeoylquinic and caffeoylshikimic acids were identified. Qualitative compositions of E. oleracea, Oenocarpus bacaba and Oenocarpus bataua leaflets were quite similar, whereas the quantitative compositions were quite different. These results provide new prospects for the valorization of roots and leaflets of E. oleracea in the pharmaceutical, food or cosmetic industry, as they are currently by-products of the açaí industry.

Physiological and transcriptomic analyses reveal mechanistic insight into the adaption of marine Bacillus subtilis C01 to alumina nanoparticles

An increasing number of studies have investigated the effects of nanoparticles (NPs) on microbial systems; however, few existing reports have focused on the defense mechanisms of bacteria against NPs. Whether secondary metabolism biosynthesis is a response to NP stress and contributes to the adaption of bacteria to NPs is unclear. Here, a significant induction in the surfactin production and biofilm formation were detected by adding Al2O3 NPs to the B. subtilis fermentation broth. Physiological analysis showed that Al2O3 NP stress could also affect the cell and colony morphogenesis and inhibit the motility and sporulation. Exogenously adding commercial surfactin restored the swarming motility. Additionally, a suite of toxicity assays analyzing membrane damage, cellular ROS generation, electron transport activity and membrane potential was used to determine the molecular mechanisms of toxicity of Al2O3 NPs. Furthermore, whole transcriptomic analysis was used to elucidate the mechanisms of B. subtilis adaption to Al2O3 NPs. These results revealed several mechanisms by which marine B. subtilis C01 adapt to Al2O3 NPs. Additionally, this study broadens the applications of nanomaterials and describes the important effects on secondary metabolism and multicellularity regulation by using Al2O3 NPs or other nano-products.

Oenocarpus bacaba and Oenocarpus bataua Leaflets and Roots: A New Source of Antioxidant Compounds

Native palm trees fruit from the Amazonian rainforest, Oenocarpus bacaba and Oenocarpus bataua, are very often used in the diet of local communities, but the biological activities of their roots and leaflets remain poorly known. Total phenolic content (TPC) and antioxidant activity of root and leaflet extracts from Oenocarpus bacaba and Oenocarpus bataua were assessed by using different chemical assays, the oxygèn radical absorbance capacity (ORAC), the 2,2-diphenyl-l-picrylhydrazyl (DPPH) free radical-scavenging capacity and the ferric-reducing ability of plasma (FRAP). Cellular antioxidant activity and cytotoxicity were also measured in Normal Human Dermal Fibroblasts. The polyphenolic composition of Oenocarpus extracts was investigated by LC-MSⁿ. Oenocarpus leaflet extracts were more antioxidant than root extracts, being at least as potent as Euterpe oleracea berries known as superfruit. Oenocarpus root extracts were characterized by hydroxycinnamic acids (caffeoylquinic and caffeoylshikimic acids), while leaflet extracts contained mainly caffeoylquinic acids and C-glycosyl flavones. These results suggest that leaflets of both Oenocarpus species could be valorized as a new non-cytotoxic source of antioxidants from Amazonia, containing hydroxycinnamic acids and flavonoids, in the pharmaceutical, cosmetic or agri-food industry.

Evaluation of antimutagenic and protective effects of Parkinsonia aculeata L. leaves against H2O2 induced damage in pBR322 DNA

The in vitro antimutagenic and DNA protecting potential of organic (methanol, hexane, n-butanol) and aqueous extract/fractions of Parkinsonia aculeata L. (Fabaceae) was investigated by employing Ames assay and DNA nicking assay. DNA damage by hydroxyl radicals was effectively inhibited by all the extract/fractions. A marked antimutagenic effect was observed against 4-Nitro-o-phenylenediamine and sodium azide (direct acting mutagens) and 2-Aminofluorene (indirect acting mutagen) in TA98 and TA100 strains of Salmonella typhimurium. In Ames assay, two different modes of experiments i.e. pre-incubation and co-incubation were performed and it was observed that all the extract/fractions showed better results in the pre-incubation as compared to co- incubation mode. Out of all the extract/fractions tested, n-butanol fraction was found to be the most effective in preventing DNA damage and inhibiting mutagenesis. UHPLC analysis of extract/fractions revealed presence of polyphenols such as gallic acid, catechin, chlorogenic acid, caffeic acid, umbelliferone, coumaric acid, rutin, and ellagic acid etc. DNA protecting and antimutagenic activity of this plant could be attributed to presence of these polyphenols. The results of this study indicate the presence of potent antioxidant factors in Parkinsonia aculeata L, which are being explored further for their mechanism of action.

Cu Nanoparticles Have Different Impacts in Escherichia coli and Lactobacillus brevis than Their Microsized and Ionic Analogues

Copper formulations have been used for decades for antimicrobial and antifouling applications. With the development of nanoformulations of copper that are more effective than their ionic and microsized analogues, a key regulatory question is whether these materials should be treated as new or existing materials. To address this issue, here we compare the magnitude and mechanisms of toxicity of a series of Cu species (at concentration ranging from 2 to 250 μg/mL), including nano Cu, nano CuO, nano Cu(OH)2 (CuPro and Kocide), micro Cu, micro CuO, ionic Cu(2+) (CuCl2 and CuSO4) in two species of bacteria (Escherichia coli and Lactobacillus brevis). The primary size of the particles studied ranged from 10 nm to 10 μm. Our results reveal that Cu and CuO nanoparticles (NPs) are more toxic than their microsized counterparts at the same Cu concentration, with toxicities approaching those of the ionic Cu species. Strikingly, these NPs showed distinct differences in their mode of toxicity when compared to the ionic and microsized Cu, highlighting the unique toxicity properties of materials at the nanoscale. In vitro DNA damage assays reveal that both nano Cu and microsized Cu are capable of causing complete degradation of plasmid DNA, but electron tomography results show that only nanoformulations of Cu are internalized as intact intracellular particles. These studies suggest that nano Cu at the concentration of 50 μg/mL may have unique genotoxicity in bacteria compared to ionic and microsized Cu.