Tronchuda cabbage (Brassica oleracea L. var. costata DC): scavenger of reactive nitrogen species

Deciphering the anticancer, anti-inflammatory and antioxidant potential of Ti nanoparticles fabricated using Zingiber officinale

Rapid and sustainable green technology was implemented in the current study to fabricated Ti nanoparticles. The vegetable ginger with the scientific name Zingiber officinale was employed as a biological source in the fabrication process of nanoparticles. The optical, structural, morphological, and particle size of the fabricated Ti nanoparticles were characterized with the help of UV-visible absorption spectrum, FTIR (Fourier Transform Infrared) spectrum, SEM (Scanning Electron Microscope) analysis, DLS (Dynamic Light Scattering) technique and XRD (X-ray powder diffraction) crystallography technique. The presence of spherical-shaped Ti nanoparticles with an average particle size of 93 nm was confirmed based on these characterization techniques. The anti-cancer properties of the Z. officinale mediated Ti nanoparticles were analyzed through MTT assay against cell lines MCF-7 (Human breast adenocarcinoma cell line) and concentration-dependent anti-cancer properties were observed. The anti-inflammatory capacity of the Z. officinale mediated Ti nanoparticles were examined through protein denaturation and nitric oxide scavenging assay. The antioxidant capacity of the Z. officinale mediated Ti nanoparticles were examined through DPPH assay, hydrogen peroxide radical scavenging assay, hydroxyl radical scavenging assay, and FRAP (Ferric Reducing Antioxidant Power) analysis. The fabricated Ti nanoparticles exhibited anti-inflammatory and antioxidant capacity in a concentration-dependent pattern.

Improvement of Phytopharmaceutical and Alkaloid Production in Periwinkle Plants by Endophyte and Abiotic Elicitors

Periwinkle plant represents a major source of immensely vital terpenoid indole alkaloids and natural antioxidants which are widely used in cancer chemotherapy. A pot experiment was done to evaluate the role of two periwinkle endophytes (Streptomyces sp. and Bacillus sp.) with or without abiotic elicitors (aluminum chloride, tryptophan, and chitosan) on plant biomass, physio-biochemical attributes, phytopharmaceutical constituents, and alkaloid production. Inoculation with endophyte microbes significantly increased plant growth, nitrogen, phosphorus, potassium, carotenoids, ascorbic acid, and alkaloid yield. It also decreased oxidative biomarkers (hydrogen peroxide and malondialdehyde) and had no significant effects on flavonoids and anthocyanin. In this regard, Streptomyces sp. was more effective than Bacillus sp. Foliar spraying with chitosan significantly increased plant growth, chlorophyll, ions, antioxidant capacity, phytopharmaceutical constituents (total soluble phenols, flavonoids, and anthocyanin), and alkaloid yield, associated with a decline in oxidative biomarkers. Conversely, aluminum chloride application generally increased oxidative biomarkers, which was associated with a decreasing effect on plant growth, chlorophyll, and ions. Application of either tryptophan or chitosan with endophyte microbes increased plant growth, chlorophyll, ions, antioxidants, and alkaloid; meanwhile, it decreased oxidative biomarkers. On the contrary, aluminum chloride with endophytes evoked oxidative damage that was associated with a reduction in plant growth, chlorophyll, ions, and phytopharmaceutical constituents. The current study provides a proof-of-concept of the use of the endophyte Streptomyces sp. with chitosan for enhancing periwinkle plant biomass, phytopharmaceuticals accumulation, and alkaloid production.

Trichilia catigua and Turnera diffusa extracts: In vitro inhibition of tyrosinase, antiglycation activity and effects on enzymes and pathways engaged in the neuroinflammatory process

ETHNOPHARMACOLOGICAL RELEVANCE

Flavonoids interact with multiple targets in Central Nervous System resulting in a broad neuroprotection mediated by complementary processes and synergic interactions. Therefore, flavonoid-based therapies may input positive outcomes in the prevention and early management of neurodegenerative diseases. In Brazilian folk medicine Trichilia catigua is used for its neuroactive properties, such as neurostimulant, antioxidant and anti-neuroinflammatory, while Turnera diffusa is traditionally used as a tonic in neurasthenia. Both species are known to be rich in flavonoids.

AIM OF THE STUDY

To study aqueous extracts of T. catigua and T. diffusa in terms of their antioxidant and antiglycation effects, inhibition of tyrosinase activity, and interaction with enzymes and pathways engaged in neuroinflammation. Moreover, whenever possible, to establish a relationship between the studied activities and the traditional usage of the species.

MATERIALS AND METHODS

The phenolic profiles of the aqueous extracts were validated by HPLC-DAD. The effect of the extracts over mushroom tyrosinase and 5-lipoxygenase activities, as well as their capacity to impair bovine serum albumin glycation, were assessed by in vitro assays. The anti-neuroinflammatory potential of the same extracts was evaluated by their capacity to mitigate the pro-inflammatory stimulus induced in BV-2 microglia cells by interferon-gamma.

RESULTS

T. catigua extract, a rich mixture of phenolic acids, catechins and flavonolignans, excels by its ability to decrease lipid peroxidation (EC₅₀ = 227.18 ± 9.04 μg/mL), and to work as anti-glycation agent, and inhibitor of both tyrosinase and 5-lipoxigenase (IC₅₀ = 358.84 ± 19.05 and 56.25 ± 14.53 μg/mL, respectively). However, only T. diffusa extract, mainly composed by luteolin derivatives, is able to lower NO production by BV-2 microglia cells stimulated with interferon-gamma, despite its lower activities in the other assays.

CONCLUSIONS

Overall, this work highlights the value of medicinal plant extracts as sources of bioactive flavonoid-rich extracts with neuroactive effects. Furthermore, these results support their application as alternative strategies to develop functional foods and therapeutics to fight chronic neurodegenerative disorders.

Phytochemical Characterization and In Vitro Antioxidant Properties of Four Brassica Wild Species from Italy

In the present study, we evaluated for the first time the variability of antioxidant traits of four Brassica wild species: B. incana, B. macrocarpa, B. villosa, and B. rupestris. The content of the main water-soluble antioxidants (phenolics, ascorbic acid, and total biothiols) and the in vitro antioxidant potential (1,1-diphenyl-2-picrylhydrazil (DPPH) and superoxide anion scavenging capacity) were investigated. A total of 28 polyphenolic compounds were identified by LC/MS and quantitated by HPLC/DAD analysis. Kaempferol and quercetin derivatives were the most abundant phenolics compared to hydroxycinnamoyl gentiobiosides. In the ten populations, phenolics ranged from 163.9 to 533.9 mg/100 g dry weight (d.w.), ascorbic acid from 7.6 to 375.8 mg/100 g d.w., and total biothiols from 0.59 to 5.13 mg/100 g d.w. The different classes of phytochemicals were separated using solid-phase extraction at increasing methanol concentrations, and the antioxidant power of fractionated extracts was evaluated. The superoxide anion scavenging activity was significantly correlated to phenolics, particularly to flavonol derivatives, while DPPH was mainly related to ascorbic acid content. The present findings improve the knowledge of the phytochemical composition of Italian Brassica wild species by showing the great diversity of phytochemicals among populations and highlighting their importance as a valuable genetic resource for developing new cultivars with improved bioactive content.

Nitration of Tyrosine in the Mucin Glycoprotein of Edible Bird's Nest Changes Its Color from White to Red

The edible bird's nest (EBN) of the swiftlet Aerodramus fuciphagus, a mucin glycoprotein, is usually white in color, but there also exist the more desirable red or "blood" EBN. The basis of the red color has been a puzzle for a long time. Here, we show that the nitration of the tyrosyl residue to the 3-nitrotyrosyl (3-NTyr) residue in the glycoprotein is the cause of the red color. Evidence for the 3-NTyr residue comes from (a) the quantitative analysis of 3-NTyr in EBN by enzyme-linked immunosorbent assay, (b) the ultraviolet-visible absorption spectra of red EBN as a function of pH being similar to 3-nitrotyrosine (3-NT), (c) the change in the color of red EBN from yellow at low pH to red at high pH just like 3-NT, and (d) strong Raman nitro bands at 1330 cm^-1 (symmetric -NO₂ stretch) and 825 cm^-1 (-NO₂ scissoring bend) for red EBN. The high concentrations of nitrite and nitrate in red EBN are also explained.

Polyphenolic profile and antioxidant activities of Madeiran elderberry (Sambucus lanceolata) as affected by simulated in vitro digestion

The aims of this study were twofold: a) to provide a detailed report on the phenolic composition and antioxidant activity of fresh berries and leaves of Sambucus lanceolata (Madeiran elderberry); b) to study the effects caused by a simulated in vitro digestion on the composition and antioxidant activity of the berries and leaves. Seventy-seven phytochemicals, mainly polyphenols, were identified in the methanol extracts of fresh berries and leaves, with the content of polyphenols higher in berries (27.2mg·g^-1 dry extract, DE) than in leaves (25.9mg·g^-1 DE). Anthocyanins were dominant in berries, while hydroxycinnamic acids (HCAs) and flavonols were abundant in leaves. Higher antioxidant activities were found in leaves than in berries, using several in vitro assays. After the simulated in vitro digestion, the levels of polyphenols were significantly reduced, in particular those of berries (81.8% decrease). Anthocyanins were the most affected compounds during the simulated digestion. However, despite the significant loss of phenolic compounds during digestion, methanol extracts of digested berries and leaves were still able to scavenge free-radicals. Hence, the consumption of leaves and/or berries of S. lanceolata may help prevent oxidative stress.

A Guide to the Variability of Flavonoids in Brassica oleracea

Flavonoids represent a typical secondary metabolite class present in cruciferous vegetables. Their potential as natural antioxidants has raised considerable scientific interest. Impacts on the human body after food consumption as well as their effect as pharmaceutical supplements are therefore under investigation. Their numerous physiological functions make them a promising tool for breeding purposes. General methods for flavonoid analysis are well established, though new compounds are still being identified. However, differences in environmental circumstances of the studies and analytical methods impede comparability of quantification results. To promote future investigations on flavonoids in cruciferous plants we provide a checklist on best-practice in flavonoid research and specific flavonoid derivatives that are valuable targets for further research, choosing a representative species of scientific interest, Brassica oleracea.

The Anti-Inflammatory and Vasodilating Effects of Three Selected Dietary Organic Sulfur Compounds from Allium Species

The anti-inflammatory and vasodilating effects of three selected dietary organic sulfur compounds (OSC), including diallyl disulfide (DADS), dimethyl disulfide (DMDS), and propyl disulfide (PDS), from Allium species were investigated. In the anti-inflammatory activity assay, the three OSC demonstrated significant inhibition of nitric oxide (NO) and prostaglandin E₂ (PGE₂) production in LPS-induced RAW 264.7 cells. The expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX-2) in activated RAW 264.7 cells was inhibited by the three OSC, indicating that the three OSC prevented the LPS-induced inflammatory response in RAW 264.7 cells. For the vasodilative assay, the three OSC were ineffective in producing NO in SVEC4-10 cells, but they did enhance prostacyclin (PGI₂) production. The expression of COX-2 in SVEC4-10 cells was activated by DADS and DMDS. Pretreatment of SVEC4-10 cells with the three OSC decreased ROS generation in H₂O₂-induced SVEC4-10 cells. In addition, the three OSC significantly inhibited angiotensin-I converting enzyme (ACE). The up-regulation of PGI₂ production and COX-2 expression by DADS and DMDS and the reduction of ROS generation by DADS, DMDS, and PDS in SVEC4-10 cells contributed to the vasodilative effect of the three OSC. Collectively, these findings suggest that DADS, DMDS, and PDS are potential anti-inflammatory and vasodilative mediators.

The Combined Effects of Ethylene and MeJA on Metabolic Profiling of Phenolic Compounds in Catharanthus roseus Revealed by Metabolomics Analysis

Phenolic compounds belong to a class of secondary metabolites and are implicated in a wide range of responsive mechanisms in plants triggered by both biotic and abiotic elicitors. In this study, we approached the combinational effects of ethylene and MeJA (methyl jasmonate) on phenolic compounds profiles and gene expressions in the medicinal plant Catharanthus roseus. In virtue of a widely non-targeted metabolomics method, we identified a total of 34 kinds of phenolic compounds in the leaves, composed by 7 C6C1-, 11 C6C3-, and 16 C6C3C6 compounds. In addition, 7 kinds of intermediates critical for the biosynthesis of phenolic compounds and alkaloids were identified and discussed with phenolic metabolism. The combinational actions of ethylene and MeJA effectively promoted the total phenolic compounds, especially the C6C1 compounds (such as salicylic acid, benzoic acid) and C6C3 ones (such as cinnamic acid, sinapic acid). In contrast, the C6C3C6 compounds displayed a notably inhibitory trend in this case. Subsequently, the gene-to-metabolite networks were drawn up by searching for correlations between the expression profiles of 5 gene tags and the accumulation profiles of 41 metabolite peaks. Generally, we provide an insight into the controlling mode of ethylene-MeJA combination on phenolic metabolism in C. roseus leaves.

Phlorotannin extracts from fucales characterized by HPLC-DAD-ESI-MSn: approaches to hyaluronidase inhibitory capacity and antioxidant properties

Purified phlorotannin extracts from four brown seaweeds (Cystoseira nodicaulis (Withering) M. Roberts, Cystoseira tamariscifolia (Hudson) Papenfuss, Cystoseira usneoides (Linnaeus) M. Roberts and Fucus spiralis Linnaeus), were characterized by HPLC-DAD-ESI-MSn. Fucophloroethol, fucodiphloroethol, fucotriphloroethol, 7-phloroeckol, phlorofucofuroeckol and bieckol/dieckol were identified. The antioxidant activity and the hyaluronidase (HAase) inhibitory capacity exhibited by the extracts were also assessed. A correlation between the extracts activity and their chemical composition was established. F. spiralis, the species presenting higher molecular weight phlorotannins, generally displayed the strongest lipid peroxidation inhibitory activity (IC₅₀ = 2.32 mg/mL dry weight) and the strongest HAase inhibitory capacity (IC₅₀ = 0.73 mg/mL dry weight). As for superoxide radical scavenging, C. nodicaulis was the most efficient species (IC₅₀ = 0.93 mg/mL dry weight), followed by F. spiralis (IC₅₀ = 1.30 mg/mL dry weight). These results show that purified phlorotannin extracts have potent capabilities for preventing and slowing down the skin aging process, which is mainly associated with free radical damage and with the reduction of hyaluronic acid concentration, characteristic of the process.

Can phlorotannins purified extracts constitute a novel pharmacological alternative for microbial infections with associated inflammatory conditions?

Bacterial and fungal infections and the emerging multidrug resistance are driving interest in fighting these microorganisms with natural products, which have generally been considered complementary to pharmacological therapies. Phlorotannins are polyphenols restricted to brown seaweeds, recognized for their biological capacity. This study represents the first research on the antibacterial, antifungal, anti-inflammatory and antioxidant activity of phlorotannins purified extracts, which were obtained from ten dominant brown seaweeds of the occidental Portuguese coast.

Phlorotannins content was determined by the specific dimethoxybenzaldehyde (DMBA) method and a yield between 75 and 969 mg/Kg phloroglucinol units (dry matter) was obtained. Fucus spiralis ranked first, followed by three Cystoseira species. The anti-inflammatory potential of the purified extracts was assessed via inhibitory effect on nitric oxide (NO) production by lipopolysaccharide-stimulated RAW 264.7 macrophage cells, Cystoseira tamariscifolia being the one showing promising activity for the treatment of inflammation. NO scavenging ability was also addressed in cell free systems, F. spiralis being the species with highest capacity. The antimicrobial potential of the extracts was checked against five Gram-positive and four Gram-negative bacteria and three fungi strains, that commonly colonize skin and mucosa and are responsible for food contamination. The different extracts were more effective against Gram-positive bacteria, Staphylococcus epidermidis being the most susceptible species. Concerning antifungal activity, Trichophyton rubrum was the most sensitive species.

Although the molecular mechanisms underlying these properties remain poorly understood, the results obtained turn phlorotannins purified extracts a novel and potent pharmacological alternative for the treatment of a wide range of microbial infections, which usually also present an inflammatory component. In addition to the biological properties demonstrated herein, phlorotannins extracts may also be preferred, in order to avoid side effects and allergic reactions commonly associated with synthetic drugs.

Phenolic extracts from Acacia mangium bark and their antioxidant activities

Phenolic compounds are present at very high concentrations in the bark of Acacia mangium. These compounds are known to have strong antioxidant activity and thus different beneficial effects on human health. Phenolic compounds in bark of A. mangium were extracted and their antioxidant activities were investigated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging and ferric-reducing antioxidant power (FRAP) assays. A central composite design has been employed to optimize the experimental conditions for a high total phenolic content and antioxidant activity. The desirability function approach has been employed to simultaneously optimize the three responses: total phenols, antiradical activity and FRAP. An extraction time of 90 min, liquid-solid ratio of 5, and temperature of 50 degrees C was predicted for the optimum experimental conditions using the desirability function. A significant linear relationship between antioxidant potency, antiradical activity and the content of phenolic compounds of bark extracts was observed. The structures of condensed tannins isolated from A. mangium were characterized by MALDI-TOF MS analyses. Condensed tannin oligomers from A. mangium were shown to be heterogeneous mixtures consisting of procyanidin and prodelphinidin structural units with polymerization degrees up to 9.

Ficus carica L.: Metabolic and biological screening

Ficus carica L. is one of the earliest cultivated fruit trees. In this work, metabolite profiling was performed on the leaves, pulps and peels of two Portuguese white varieties of F. carica (Pingo de Mel and Branca Tradicional). Phenolics and organic acids profiles were determined by HPLC/DAD and HPLC/UV, respectively. All samples presented a similar phenolic profile composed by 3-O- and 5-O-caffeoylquinic acids, ferulic acid, quercetin-3-O-glucoside, quercetin-3-O-rutinoside, psoralen and bergapten. 3-O-Caffeoylquinic acid and quercetin-3-O-glucoside are described for the first time in this species. Leaves' organic acids profile presented oxalic, citric, malic, quinic, shikimic and fumaric acids, while in pulps and peels quinic acid was absent. The antioxidant potential of the different plant parts was checked. All materials exhibited activity against DPPH and nitric oxide radicals in a concentration-dependent way. However, only the leaves presented capacity to scavenge superoxide radical. Leaves were always the most effective part, which seems to be related with phenolics compounds. Additionally, acetylcholinesterase inhibitory capacity was evaluated, but no effect was observed. Antimicrobial potential was also assessed against several bacterial species, although no activity was noticed. This is the first study comparing the chemical composition and biological potential of F. carica pulps, peels and leaves.

Boerhaavia diffusa: metabolite profiling of a medicinal plant from Nyctaginaceae

Boerhaavia diffusa is a plant which is extensively used in folk medicine. However, when it comes to its phytochemical characterization, little attention has been given to secondary metabolites other than rotenoids and alkaloids. A metabolite profiling and biological study was undertaken in this species' leaves and roots and substantial differences were found between the two parts of the plant. The volatile composition was analysed for the first time using HS-SPME-GC-MS and several compounds, including terpenes, phenylpropanoids, indol compounds, norisoprenoids, among others, were identified. Organic acid analysis was also performed, allowing their characterization in this species for the first time, and oxalic, ketoglutaric, pyruvic, quinic and fumaric acids were identified. Quantitative differences between the two vegetal materials were found. Additionally, several flavonoids and one phenolic acid were also confirmed. Concerning the biological potential, the aqueous extract of each plant part was tested against DPPH radical, one reactive oxygen species (O(2)(-)) and one reactive nitrogen species (()NO). Moreover, activity against acetylcholinesterase, an enzyme with a well-known role in several physio-pathological processes, was assayed. When possible, the relation between the chemistry and activity displayed was established. Leaves revealed stronger antioxidant activity than roots, and acetylcholinesterase inhibition was not found in neither plant part.

Water extracts of Brassica oleracea var. costata potentiate paraquat toxicity to rat hepatocytes in vitro

Tronchuda cabbage extracts have been proven to have antioxidant potential against various oxidative species in cell free systems, though its antioxidant potential in cellular models remained to be demonstrated. In the present study, we used primary cultures of rat hepatocytes for the cellular assay system and paraquat PQ exposure as a pro-oxidant model agent, to test whether tronchuda cabbage hydrolysed water extracts provide protective or aggravating effects towards PQ-induced oxidative stress and cell death. For this purpose cellular parameters related to oxidative stress were measured, namely the generation of superoxide anion, glutathione oxidation, lipid peroxidation, intracellular ATP levels, activation of nuclear factor-kappaB (NF-kappaB), activity of antioxidant enzymes, and cell death. The obtained results demonstrated that the studied hydrolysed water extracts of tronchuda cabbage, especially rich in kaempferol (84%) and other polyphenols, namely hydroxycinnamic acids and traces of quercetin, can potentiate the toxicity of PQ in primary cultures of rat hepatocytes. These results highlight that prospective antioxidant effects of plant extracts, observed in vitro, using non-cellular systems, are not always confirmed in cellular models, in which the concentrations required to scavenge pro-oxidant species may be highly detrimental to the cells.

Targeted metabolite analysis and biological activity of Pieris brassicae fed with Brassica rapa var. rapa

For the first time, an insect-plant system, Pieris brassicae fed with Brassica rapa var. rapa, was tested for its biological capacity, namely, antioxidant (DPPH*, *NO, and O(2)*- radicals) and antimicrobial (bacteria and fungi) activities. Samples from the insect's life cycle (larvae, excrements, exuviae, and butterfly) were always found to be more efficient than the host plant. Also, P. brassicae materials, as well as its host plant, were screened for phenolics and organic acids. The host plant revealed higher amounts of both compounds. Two phenolic acids, ferulic and sinapic, as well as kaempferol 3-Osophoroside, were common to insect (larvae and excrements) and plant materials, with excrements being considerably richer. Detection of sulfated compounds in excrements, absent in host plant, revealed that metabolic processes in this species involved sulfation. Additionally, deacylation and deglycosilation were observed. All matrices presented the same organic acids qualitative profile, with the exception of excrements.

New phenolic compounds and antioxidant potential of Catharanthus roseus

Screening of the phenolic compounds from seeds, stems, leaves and petals of Catharanthus roseus (L.) G. Don (cv. Little Bright Eye) was achieved by HPLC-DAD-ESI-MS/MS. This is the first detailed study of noncolored phenolics in C. roseus, which allowed the characterization of three caffeoylquinic acids and fifteen flavonol glycosides (di- and trisaccharides of kaempferol, quercetin and isorhamnetin). Fifteen compounds are reported for the first time in this species. The scavenging ability of the different plant matrices was assessed against DPPH(*) radical and against reactive oxygen (superoxide radical) and a reactive nitrogen (nitric oxide) species. A concentration-dependent protective effect was observed for seeds and tissues, with petals shown to be the most active.