A novel and effective natural product-based immunodetection tool for TNT-like compounds.

This study aimed to develop a fast and reliable protocol for Trinitrophenol-Tris(hydroxymethyl)aminomethane (TNP-Tris) detection applying a ß-lactamase-fusion protein of choice, the natural product-based immunoreagent tool of competitive sensitivity developed herein for the first time. Since the fusion protein 11B3-scFv-ß-lactamase is constructed from a scFv-antibody (11B3) linked to an enzyme (ß-lactamase), the step related to the use of secondary antibody in the enzyme-linked immunosorbent assay (ELISA) is completely omitted. Indeed, this fusion protein itself serves both as binding mean of the antigen model and detecting agent, due to the presence of the naturally occurring enzyme. In such a way, it actually affords the one-step TNP-Tris detection reaching a promising LOD value of 45 ± 2 fmol or 157 ± 6 pg/mL. Taken all together, the current protocol does represent much cheaper and significantly less-time consuming alternative compared both to the recombinant antibodies and recombinant phages, previously designed means in our labs for the same purpose.

3.5-scFv-ß-lactamase, a new protein detector of picric acid, the highly nitrated organic explosive.

A new protein detector of 2,4,6-trinitrophenol (TNP, picric acid) is concisely reported herein for the first time. In brief, the gene of a specific scFv fragment, namely 3.5, was fused separately with the gene of ß-lactamase and, subsequently, expressed in the periplasmic space of Escherichia coli, affording in such a way the recombinant fusion protein 3.5-scFv-ß-lactamase. This bifunctional immunoreagent tool was further convincingly demonstrated for being capable to directly detect trinitrophenol-tris(hydroxymethyl)aminomethane (TNP-Tris), a less toxic TNP derivative of choice compared to TNP itself, with competitive sensitivity (50 ± 2 fmol or 175 ± 6 pg/mL).[Formula: see text].

A neglected natural source for targeting glioblastoma.

The cytotoxicity of the methanol extract of the freshwater sponge Ochridaspongia rotunda (Arndt, 1937) (Malawispongiidae) was evaluated by MTT assay at in vitro conditions against three brain tumour cell lines (Neuro-2A, U-251 MG and U-87 MG). The extract was actually found to be most effective against the malignant glioma U-251 MG cells reaching a promising IC50 value of 1.87 ± 0.09 µg/mL at 96 h. However, it exhibited only a bit of cytotoxicity (IC50 321.14 ± 11.29 µg/mL, 96 h) towards the normal cells. Also, this sponge extract was 5-fold more selective for U-251 MG versus U-87 MG cells. Finally, monitoring genotoxicity at chromosomal level using the micronucleus test practically revealed lack of any significant toxicity of O. rotunda extract, compared to doxorubicin.

Raspberry seeds extract selectively inhibits the growth of human lung cancer cells in vitro.

This study was focused on in vitro cytotoxicity screening of the raspberry seeds methanol extract towards a number of cancer cell lines of human origin. The tested extract at the preferred concentrations (IC50 <30 µg/mL) inhibited only the growth of the lung cancer A-549 cells (IC50 = 14.07 ± 0.96 µg/mL). At the same time, it was practically inactive (IC50 >300 µg/mL) and non-mutagenic towards normal MRC-5 lung cells. Finally, the extract potently scavenged both OH· (IC50 = 20.11 ± 1.77 µg/mL) and O2-· (IC50 = 47.23 ± 3.82 µg/mL), the free radicals of proved relevance for cancer pathophysiology. Though seeds were enriched with phenolic compounds (TPC = 5.21 ± 0.07 mg GAE/g), anthocyanins were present in traces only (TAC = 0.07 ± 0.003 mg cyn-3-glu/g), while flavonoids were not detected at all. This is the first report on anti-lung cancer potential of the seeds of any soft fruit.

Polarography as a technique of choice for the evaluation of total antioxidant activity: The case study of selected Coprinus Comatus extracts and quinic acid, their antidiabetic ingredient.

This study was focused on in vitro screening of the total antioxidant activity of the selected extracts of the mushroom Coprinus comatus and quinic acid, one of their antidiabetic ingredients, by an uncommon electrochemical assay. Indeed, direct current (DC) polarographic HydroxoPerhydroxo Mercury(II) Complex (HPMC) assay based on decrease of anodic limiting current originating from HPMC formation in alkaline solutions of hydrogen peroxide at potential of mercury dissolution, observed upon gradual addition of antioxidants, was applied herein for the estimation of the natural products' antioxidativity. Quinic acid was found to exhibit most promising antioxidant potential (4.0 ± 0.2%µL-1) being ≈ 2-fold more active than the screened C. comatus extract samples. Actually, such a finding puts some light on the antioxidativity of cyclic polyols, well understimated class of organic compounds, compared to aromatic (poly)phenolics. As a low cost, easy-to handle and accurate this polarographic assay may be thoroughly recommended for much broader use. [Formula: see text].

New cytotoxic natural products from the mangrove biome: covering the period 2007-2015.

Nowadays, the mangrove biome is considered to be a profound resource of natural products usually possessing cytotoxicity of a broader range. Covering the period 2007-2015, a total of 21 new naturally occurring compounds has stood out. For example, xylogranin B and swietephragmin C were found to exhibit very potent cytotoxic activity against the colon HCT-116 cells reaching IC50 values of 0.05 and 0.06 µM, respectively. Bearing in mind the efficacy of the majority compounds in the preliminary in vitro screens, these studies should be expanded to both ex vivo and in vivo screens including the evaluation of the relevant toxicological profiles.

Saliva could act as an emulsifier during oral processing of oil/fat.

Human saliva is a fluid naturally secreted in the oral cavity that interacts with food and food components for bolus formation, structure degradation, as well as lubrication. Because of the presence of salivary proteins, we speculate that saliva could also function as an effective emulsifier during oral processing of oil/fat. In this preliminary work, experiments were then designed to test this hypothesis. Whole human saliva from three healthy subjects were collected and analyzed for protein content, surface tension, and molecular weight distribution. Saliva emulsions were obtained both in vitro one and in situ for all three participating subjects. Droplet size distribution, zeta potential, and microstructure of such emulsions were examined immediately after the emulsification. Results show that stable saliva emulsions can be produced during oral processing of either pure oil (rapeseed oil) or fat food (pork belly in this work). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that protein fractions of 27 and 55 kDa molecular weights were favored for emulsion formation. This work suggests that human saliva could function as an effective emulsifier and oral emulsification could be an important mechanism for the oral processing of oil/fat. Despite being preliminary, findings from this work provide a new scientific insight to our understanding of the oral behavior of oil/fat and their sensory perception. PRACTICAL APPLICATIONS: Food industry is currently under a growing pressure to use novel techniques and ingredients to minimize the use of oil/fat in food products but without compromising its sensory quality. However, food industry has limited progresses because of the lack of understanding of the mechanisms of oral sensation and perception of oil/fat. Whereas there have been extensive debates about the sensory mechanisms of oil/fat, this work takes a step back by examining the oral behavior of oil/fat. Findings show that saliva can actually function as emulsifier to oil/fat, which means that ingested oil/fat will be dispersed and converted into an emulsion at the oral stage. The findings from this work offer food industry new insight on the sensory mechanisms of oil/fat.

A brief review of potent anti-CNS tumourics from marine sponges: covering the period from 1994 to 2014.

This review covers the 1994-2014 literature data published for anti-CNS tumour natural products isolated from marine sponges. The focus was on highly potent antitumourics. It describes only eight promising bioactives (screened on even less number of the respective cell lines) suggesting that brain tumours actually represent quite a hot topic for the natural product research community worldwide.

The redox couple avarol/avarone in the fight with malignant gliomas: the case study of U-251 MG cells.

This study aimed to screen in vitro antitumour activity of the redox couple avarol/avarone against the human malignant glioma cell line U-251 MG for the first time. Compared both with avarol and positive controls used (temozolomide and doxorubicin), avarone was found to be the most active compound with IC50 value below 1 µM (IC50 0.68 ± 0.04 µM, 96 h). Considerable less DNA damage in the cells treated with avarol and avarone vs. doxorubicin (105 & 123% vs. 299%, respectively; untreated U-251 MG cells were used as a control, 100%), coupled with no sign of cytotoxicity against the normal human foetal lung fibroblast MRC-5 cells (IC50 > 100 µM), has actually pointed out the importance of this marine sesquiterpenoid quinone structure as a promising lead compound in development of novel brain chemotherapeutics.

Lignicolous fungi hydrodistilled extracts may represent a promising source of natural phenolics.

In vitro evaluation of total phenolic contents and antiradical activities of the lignicolous fungi Fomes fomentarius and Schizophyllum commune hydrodistilled extracts was the subject of this study. This preliminary screening included four free radical species evaluated by UV-vis (DPPH•, ABTS• and •NO) and EPR (Asc•), respectively. According to the experimental data obtained, both F. fomentarius and S. commune hydrodistilled extracts may be considered as promising sources of phenolic natural products (157 and 138 mg GAE/g d.e., respectively) and other bioactives showing good anti-DPPH (1.31 µg/mL) and anti-Asc (70.40%) radical activities, respectively, at in vitro conditions.