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Acmella radicans (Asteraceae) is a plant native to America. Despite it having medicinal attributes, studies on its phytochemical properties are scarce, and biotechnological studies do not exist for this species. In this study, we established an adventitious root culture from A. radicans internodal segments in shake flasks with indole-3-butyric acid (IBA), and then elicited it with jasmonic acid (JA) and salicylic acid (SA). The total phenolic content and antioxidant activity were evaluated, and a comparison was made using in vitro plantlets and wild plants. Internodal segments with 0.1 mg/L IBA showed 100% root induction and exhibited better growth after transfer to shake flasks with MS liquid culture medium. JA had a significant effect on biomass increase compared to unelicited roots, mainly with 50 µM JA (28%), while SA did not show significant results. Root elicited with 100 µM (SA and JA) showed a 0.34- and 3.9-fold increase, respectively, in total phenolic content (TPC) compared to the control. The antioxidant activity was also significant, and a lower half-maximal inhibitory concentration (IC 50 ) was observed as the AJ concentration increased. Roots elicited with AJ (100 µM) exhibited high antioxidant activity with DPPH (IC 50 = 9.4 µg/mL) and ABTS (IC 50 = 3.3 µg/mL) assays; these values were close to those for vitamin C (IC 50 = 2.0 µg/mL). The TPC and antioxidant activity of in vitro plants and root cultured in shake flasks showed the lowest values in most cases; even the root cultures without elicitation were better than those of a wild plant. In this study, we demonstrated that A. radicans root culture is capable of producing secondary metabolites, while its production and antioxidant activity can be enhanced using jasmonic acid.

Various ferulic acid (FA) dimers occurring in plant cell walls, such as 8-5-, 8-O-4-, 5-5-, and 8-8- coupled dimers, are effective antioxidants and potential antimicrobials. It is necessary to access these diferulates as reference compounds to validate those isolated from plants. 3,6-bis(4-hydroxy-3-methoxyphenyl)-tetrahydrofuro-[3,4-c]furan-1,4-dione, a 8-8-coupled FA dilactone generated from ferulic acid via radical coupling, has been used to synthesize 8-8-coupled FA dimers although few reports investigated the distribution of products and mechanisms involved in the transformation of FA dilactone. In this work, the FA dilactone, obtained from FA by a peroxidase-catalyzed radical coupling, was reacted under various base/acid conditions. Effects of reaction conditions and workup procedures on the distribution of products were investigated by GC-MS. The isolated products from such treatments of FA dilactone were characterized by NMR. New derivatives of FA dimer including 2-(4-hydroxy-3-methoxybenzylidene)-3-(hydroxyl-(4-hydroxy-3-methoxyphenyl)methyl)succinic acid and 2-(bis(4-hydroxy-3-methoxyphenyl)-methyl)-succinic acid were produced from NaOH treatment. Another novel 8-8-coupled cyclic FA dimer, diethyl 6-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-7-methoxy-1,2-dihydronaphthalene-2,3-dicarboxylate was identified in products from FA dilactone treated by dry HCl in absolute ethanol. Mechanisms involved in such transformations were proposed., Competing Interests: The authors declare no conflict of interest.

The current study focuses on the analysis of in vitro biological activity of extract from bark of Norway spruce (Picea Abies), which can find potential application in food and cosmetic industry and pharmacology. Milled bark was subjected to Soxhlet extraction and supercritical fluid extraction to obtain two ethanol extracts. These extracts were further used to obtain their pre-extracts to n-hexane. It was investigated whether beta-sitosterol exhibits bacteriostatic activity necessary to observe antimicrobial and antifungal activity of methyl dehydroabiatate. This synergic effect and bacteriostatic activity of beta-sitosterol have not been previously reported. The greatest inhibition zone of n-hexane pre-extracts was confirmed in bacterium Pseudomonas aeruginosa (0,9 - 1,5 cm) and yeast Alternaria alternata (0,7 - 1,6 cm). It is novel, the antioxidant, antimicrobial and antifungal activity of spruce bark extracts assessed in terms of food and cosmetic fortification., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: Flavonoid glycosides have many beneficial effects on health, but these bioactivities tend to decrease after oral administration owing to their poor lipophilicity. In this study, a facile whole-cell-based method was developed for selective preparation of monoester or diester of troxerutin, a flavonoid derivative. In addition, the bioavailabilities and antioxidant properties of troxerutin and its acylated derivatives were also investigated in cells., Results: Pseudomonas aeruginosa and Pseudomonas stutzeri cells showed high catalytic efficiency (substrate conversion > 90%) and different preferences for troxerutin, resulting in the production of its monoester (TME) and diester (TDE), respectively. The logP values of troxerutin, TME, and TDE were - 2.04 ± 0.10, - 0.75 ± 0.08, and 1.51 ± 0.05 and their P app values were 0.34 × 10 -6  ± 0.05, 0.99 × 10 -6  ± 0.12, and 1.54 × 10 -6  ± 0.17 cm/s, respectively. The results of hydroxyl radical, ABTS, and ORAC assays indicated that the antiradical activities of acylated derivatives did not exceed that of troxerutin, but showed higher inhibition effects upon 2,2'-azobis(2-amidinopropane) dihydrochloride-induced erythrocyte hemolysis than that of troxerutin (P < 0.05)., Conclusion: A facile and efficient whole-cell biocatalysis method was developed to synthesize troxerutin-acylated derivatives, markedly enhancing the bioavailability and antioxidant activities of troxerutin in cells. Additionally, the mechanism underlying the observed difference in the antioxidant activities of troxerutin and its esters was ascribed to both their free radical scavenging abilities and distribution on the cell membrane surface.

An effective method to functionalize chitosan with 4-hexyloxyphenol (HP) under homogeneous reaction conditions was developed using laccase as the catalyst. The resulting copolymer was characterized for chemical structure, grafted-HP content, surface morphology, thermal stability, antioxidant capacity, hydrophobic properties and tensile strength. Solid-state 13 C NMR spectrum confirmed the incorporation of HP onto chitosan. X-ray diffraction (XRD) showed a decrease in the degree of crystallinity for laccase/HP treated chitosan compared to pure chitosan. The grafted-HP content in laccase/HP-treated chitosan first increased and then declined with increase of the initial HP/chitosan ratio. A heterogeneous surface with spherical particles on the laccase/HP treated chitosan was observed by environmental scanning electron microscopy (ESEM) and scanning probe microscopy (SPM). The laccase/HP treatment of chitosan improved the thermal stability of copolymer. More significantly, the HP functionalized chitosan showed greatly improved ABTS + and DPPH radicals scavenging capacity, compared with pure chitosan. The hydrophobicity property of the HP functionalized chitosan also significantly increased although its tensile strength decreased. This new type of composite with double functionalities (i.e., antioxidant and hydrophobic) could potentially be used as food packaging materials or coating agents., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Softwood bark is an important source for producing chemicals and materials as well as bioenergy. Extraction is regarded as a key technology for obtaining chemicals in general, and valorizing bark as a source of such chemicals in particular. In this paper, properties of 237 compounds identified in various studies dealing with extraction of softwood bark were described. Finally, some challenges and perspectives on the production of chemicals from bark are discussed., (Copyright © 2017 Elsevier Inc. All rights reserved.)

For the first time, a pale amorphous coumarin derivative, 5-methoxyl aesculetin (MOA), was isolated from the dried bark of Fraxinus rhynchophylla Hance (Oleaceae). MOA modulates cytokine expression in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages, but the precise mechanisms are still not fully understood. We determined the effects of MOA on the production of inflammatory mediators and pro-inflammatory cytokines in the LPS-induced inflammatory responses of RAW 264.7 macrophages. MOA significantly inhibited the LPS-induced production of nitric oxide (NO), prostaglandin E₂ (PGE₂), tumor necrosis factor-α (TNF-α), interleukin-6, and interleukin-1β. It also effectively attenuated inducible nitric oxide (NO) synthase, cyclooxygenase-2, and TNF-α mRNA expression and significantly decreased the levels of intracellular reactive oxygen species. It inhibited phosphorylation of the extracellular signal-regulated kinase (ERK1/2), thus blocking nuclear translocation of activation protein (AP)-1. In a molecular docking study, MOA was shown to target the binding site of ERK via the formation of three hydrogen bonds with two residues of the kinase, which is sufficient for the inhibition of ERK. These results suggest that the anti-inflammatory effects of MOA in RAW 264.7 macrophages derive from its ability to block both the activation of mitogen-activated protein kinases (MAPKs) and one of their downstream transcription factors, activator protein-1 (AP-1). Our observations support the need for further research into MOA as a promising therapeutic agent in inflammatory diseases.

Unlabelled: Enteral immunomodulatory nutrition is considered as a promising therapy for the treatment of acute lung injury and acute respiratory distress syndrome (ALI/ARDS). However, there are still some divergences, and it is unclear whether this treatment should be recommended for patients with ALI/ARDS. Therefore, we conducted this systematic review and meta-analysis to assess the efficacy and safety of an enteral immunomodulatory diet on the clinical outcomes of ALI/ARDS patients., Methods: We retrieved potentially relevant clinical trials though electronic databases. All trials of enteral immunomodulatory diet for ALI/ARDS were included. Analyses of the overall all-cause mortality, 28-day ventilator-free days and 28-day intensive care unit (ICU) free days were conducted., Results: In total six controlled trials were evaluated. The pooled results did not show a significant reduction in the risk of all-cause mortality (M-H RR (the overall Mantel-Haenszel relative risk), 0.81 (95% CI, 0.50-1.31); p = 0.38; 6 trials, n = 717) in ALI/ARDS patients treated with the immunomodulatory diet. This treatment also did not extend the ventilator-free days and ICU-free days. However, patients with high mortality might benefit from this treatment., Conclusions: The enteral immunomodulatory diet could not reduce the severity of the patients with ALI/ARDS. Whereas, for ALI/ARDS patients with high mortality, this treatment might reduce the all-cause mortality, but its use should be treated with discretion.

Oxidative stress-mediated cellular injury has been considered as a major cause of neurodegenerative diseases including Alzheimer and Parkinson diseases. The scavenging of reactive oxygen species (ROS) mediated by antioxidants may be a potential strategy for retarding the disease's progression. Macranthoin G (MCG), isolated from Eucommia ulmoides, is a derivative from chlorogenic acid methyl ester and caffeic acid. This study is aimed to investigate the protective role of MCG against the cytotoxicity induced by hydrogen peroxide (H2O2) and to elucidate potential protective mechanisms in rat pheochromocytoma (PC12) cells. The results showed that the treatment of PC12 cells with MCG prior to H2O2 exposure effectively increased the cell viability, and stabilized the mitochondria membrane potential (MMP); furthermore, it enhanced the antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) and the levels of intracellular glutathione (GSH); it also decreased the malondialdehyde (MDA) content, intracellular ROS, caspase-3 activation, as well as cell apoptosis. In addition, the MCG treatment minimized the cell injury by H2O2 via down-regulation of the NF-κB pathway as well as activation of phosphorylation of IκBα, p38, and the extracellular signal-regulated kinase (ERK). These results showed that that MCG is promising as a potential therapeutic agent for neurodegenerative diseases induced by oxidative damage and should be encouraged for further research., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Oxidative stress has been considered as a major cause of cell damage in various neurodegenerative disorders. One of the reasonable strategies for delaying the disease's progression is to prevent reactive oxygen species (ROS) mediated cellular injury by dietary or pharmaceutical augmentation of free radical scavengers. Isocampneoside II (ICD) is an active phenylethanoid glycoside isolated from the medicinal hardwood genus Paulownia. This study was designed to explore free radical scavenging potential of ICD in different in vitro systems and its protective role in hydrogen peroxide (H₂O₂)-induced oxidative stress and apoptotic death in cultured rat pheochromocytoma (PC12) cells. The results showed ICD eliminated approximately 80.75% superoxide radical at the concentration of 0.1mg/ml and inhibited metal chelating by 22.07% at 8 mg/ml. Additionally, ICD showed a strong ability on reducing power and provided protection against oxidative protein damage induced by hydroxyl radicals. Pretreatment of PC12 cells with ICD prior to H₂O₂ exposure elevated cell viability, enhanced activity of superoxide dismutase and catalase, and decreased levels of malondialdehyde and intracellular ROS. Furthermore, ICD inhibited cell apoptosis and Bax/Bcl-2 ratio induced by H₂O₂. These findings suggested ICD may be considered as a potential antioxidant agent and should encourage for further research in neurodegenerative diseases., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The antioxidant activity of the phenolic compounds present in industrial black liquors obtained from the two cooking processes (kraft and sulphite) used in Portugal to produce Eucalyptus globulus pulp was evaluated. The black liquors treated at several pH values were extracted with ethyl acetate. Phenolic fractions were further separated by liquid chromatography of the crude extracts of kraft liquor at pH = 6 and sulphite liquor at the original pH. Total phenolic content was determined in terms of gallic acid equivalents (Folin-Ciocalteu colorimetric method), and the antioxidant activity in the crude extracts at several pH values and in the separated fractions was measured using the DPPH test for radical scavenging capacity. The total phenolic content of crude extracts and separated fractions ranged from 92.7 to 181.6 and from 91.6 to 1,099.6 mg GAE/g, respectively, while the antioxidant activity index (AAI) ranged from 2.20 to 3.41 and from 2.21 to 11.47 respectively, showing very strong antioxidant activity in all studied cases. The fractions separated by column chromatography were submitted to mass spectrometry analysis and the results were compared to others in the literature of natural products, mainly from Eucalyptus, and the characteristic bands of functional groups were identified by ¹H-NMR and FTIR. These methods allowed the identification of 17 phenolic compounds.

Recently we demonstrated that in inflammatory bowel disease (IBD) macrophage-oxidative burst activity is increased and NADPH oxidase mRNA is induced. The herbal phenylethanoid acteoside isolated from Plantago lanceolata L. was shown to exhibit anti-oxidative potential. Using the dextran sulphate sodium (DSS)-induced colitis model, in this study we have assessed whether systemic application of acteoside affects colitis. Colitis was induced by DSS in Balb/c mice. Treatment with acteoside (120, 600 microg/mouse/day) was performed intraperitoneally. The colon lengths were determined. Colonic tissue was scored histologically (max. score 8) by a blinded investigator. T cells isolated from mesenteric lymph nodes (MLN) were stimulated with anti-CD3 antibody in the presence of interleukin (IL)-2 (final concentration 10 U/ml). After incubation for 24 h, IL-1beta, IL-6, IL-12 tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma levels in supernatants were analysed by the beadlyte cytokine detection system. Histological scoring of colonic tissue revealed that application of acteoside was followed by a significantly improved histological score. In acute colitis the histological score was 3.2 with acteoside versus 5.2 with phosphate-buffered saline (PBS) (P < 0.02). In chronic colitis both 120 microg (3.3 versus 5.2) or 600 microg acteoside (3.0 versus 5.2) significantly ameliorated colitis (both P < 0.02). Stimulated MLN from mice with chronic DSS-induced colitis treated with acteoside showed a significant down-regulation of IFN-gamma secretion (195 pg/ml with 600 microg acteoside versus 612 pg/ml with PBS, P < 0.02). Inhibition of oxidative burst activity with acteoside reduced mucosal tissue damage in DSS colitis and could be a therapeutic alternative for IBD treatment. Further studies of this agent are warranted.