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Sticholysin I (StI) is a pore-forming toxin (PFT) belonging to the actinoporin protein family characterized by high permeabilizing activity in membranes. StI readily associates with sphingomyelin (SM)-containing membranes originating pores that can lead to cell death. Binding and pore-formation are critically dependent on the physicochemical properties of membrane. 1-palmitoyl-2-oleoylphosphatidylcholine hydroperoxide (POPC–OOH) is an oxidized phospholipid (OxPL) containing an –OOH moiety in the unsaturated hydrocarbon chain which orientates towards the bilayer interface. This orientation causes an increase in the lipid molecular area, lateral expansion and decrease in bilayer thickness, elastic and bending modulus, as well as modification of lipid packing. Taking advantage of membrane structural changes promoted by POPC-OOH, we investigated its influence on the permeabilizing ability of StI. Here we report the action of StI on Giant Unilamellar Vesicles (GUVs) made of 1-palmitoyl-2-oleoylphosphatidylcholine (POPC) and SM containing increasing amount of POPC-OOH to assess vesicle permeability changes when compared to OxPL-lacking membranes. Inclusion of POPC-OOH in membranes did not promote spontaneous vesicle leaking but resulted in increased membrane permeability due to StI action. StI activity did not modify the fluid-gel phase coexistence boundaries neither in POPC:SM or POPC-OOH:SM membranes. However, the StI insertion mechanism in membrane seems to differ between POPC:SM and POPC-OOH:SM mixtures as suggested by changes in the time course of monolayer surface tension measurements, even though a preferable binding of the toxin to OxPL-containing systems could not be here demonstrated. In summary, modifications in the membrane imposed by lipid hydroperoxidation favor StI permeabilizing activity.

Resumen Introduccion Obtener margenes libres en cirugia conservadora del cancer de mama (CCCM) es esencial para evitar la recurrencia local, precisando para ello la reintervencion en multiples ocasiones. La ablacion por radiofrecuencia (ARF) de los margenes tras tumorectomia parece ser una herramienta util para evitar las reintervenciones, aunque con insuficiente evidencia. En este estudio se analiza la eficacia y seguridad de la ARF tras la CCCM para obtener margenes libres. Metodos Estudio experimental, no aleatorizado, realizado en un grupo intervencion de 40 pacientes al que se aplico ARF tras tumorectomia y exeresis posterior de los margenes, y otro grupo control historico de 40 pacientes al que se realizo CCCM. En el grupo intervencion, se analizo el efecto de la ARF sobre la viabilidad de las celulas tumorales en los margenes extirpados. Se realizo ademas un analisis comparativo sobre el porcentaje de reintervenciones, las complicaciones y el resultado estetico en ambos grupos. Resultados Se estudiaron 240 margenes extirpados tras ARF, evidenciando un elevado numero de margenes libres. Comparado con el grupo control, disminuyo significativamente el numero de reintervenciones (0% vs. 12%; p = 0,02), sin hallar diferencias respecto a las complicaciones (5% vs. 10%; p = 0,67) ni al resultado estetico (excelente o bueno 92,5% vs. 95%; p = 0,3). Conclusiones La ARF tras tumorectomia es una tecnica sencilla, segura y eficaz para la obtencion de margenes libres, y permite reducir las reintervenciones sin afectar a las complicaciones ni al resultado estetico.

Background: Foods including probiotics are considered “functional foods.” As an alternative to dairy products, we investigated the behavior of Lactobacillus casei when exposed to low-pH fruit juice. Juices of fruits such as pineapple, raspberry, and orange were assessed. Free and microencapsulated forms of L. casei were compared, and the viability of the probiotic was evaluated under storage at 4°C for 28 d. Microbiological analyses were carried out to ensure a safe and healthy product for consumers who look for foods with probiotics from sources other than dairy. Results: Low pH affected L. casei survival during storage depending on the type of fruit juice. In the case of pineapple juice, some microcapsules were broken, but microcapsules recovered at the end of the storage period had 100% viability (2.3 × 107 CFU/g spheres). In the case of orange juice, more than 91% viability (5.5 × 106 CFU/g spheres) was found. In raspberry juice, viability decreased rapidly, disappearing at the end of the storage period, which was caused by the absorption of high concentrations of anthocyanin inside microcapsules more than low pH. Conclusion: Low pH affected the survival of L. casei under refrigeration; even when they were microencapsulated, acidic conditions impacted their viability. Although pH affects viability, its value is very sensitive and will depend on the type of fruit juice and its composition. Some fruit juices contain compounds used as substrates for Lactobacillus and other compounds with antimicrobial effects.How to cite: Olivares A, Soto C, Caballero E, et al. Survival of microencapsulated Lactobacillus casei (prepared by vibration technology) in fruit juice during cold storage. Electron J Biotechnol 2019;42. https://doi.org/10.1016/j.ejbt.2019.10.002. Keywords: Alginate, Fruit juice, Fruit, Lactobacillus casei, Low pH, Microencapsulation, Pasteurization, Probiotics, Vibration technology, Anthocyanins

The Escherichia coli neutral M1-aminopeptidase (ePepN) is a novel target identified for the development of antimicrobials. Here we describe a solid-phase multicomponent approach which enabled the discovery of potent ePepN inhibitors. The on-resin protocol, developed in the frame of the Distributed Drug Discovery (D3) program, comprises the implementation of parallel Ugi-azide four-component reactions with resin-bound amino acids, thus leading to the rapid preparation of a focused library of tetrazole-peptidomimetics (TPMs) suitable for biological screening. By dose-response studies, three compounds were identified as potent and selective ePepN inhibitors, as little inhibitory effect was exhibited for the porcine ortholog aminopeptidase. The study allowed for the identification of the key structural features required for a high ePepN inhibitory activity. The most potent and selective inhibitor (TPM 11) showed a non-competitive inhibition profile of ePepN. We predicted that both diastereomers of compound TPM 11 bind to a site distinct from that occupied by the substrate. Theoretical models suggested that TPM 11 has an alternative inhibition mechanism that doesn't involve Zn coordination. On the other hand, the activity landscape analysis provided a rationale for our findings. Of note, compound TMP 2 showed in vitro antibacterial activity against Escherichia coli. Furthermore, none of the three identified inhibitors is a potent haemolytic agent, and only two compounds showed moderate cytotoxic activity toward the murine myeloma P3X63Ag cells. These results point to promising compounds for the future development of rationally designed TPMs as antibacterial agents.

This study evaluated the use of flour from overripe whole bananas (OWBF), which are generally discarded, as an ingredient of muffins. Products with OWBF in 400 and 500 g/kg of total flour were highly acceptable, obtaining an average rating of 5.6 points for odour, 5.7 points for colour, 5.2 points for taste, and 5.6 points for mouth texture, in a 7 points hedonic evaluation (1: dislike so much, to 7: like so much) done by non-trained panelists. Though OWBF has a high levels of dietary fibre (181.9 g/kg) and resistant starch (35 g/kg), a low total starch content (57 g/kg) and high simple sugars content were observed (714.2 g/kg of carbohydrates were glucose plus fructose). The evaluation of the glycaemic response to the consumption of a muffin made with OWBF showed no differences with white bread (reference food), with a glycaemic index of 84 ± 38 for the muffin. The glycaemic load (GL) of 50 g portion of muffin with OWBF was 15, which classified the product as intermediate GL. Then, the use of OWBF in muffins is possible and acceptable, and the consumption of OWFB does not affect adversely the glycaemic response in overweight people.

Sticholysin II (StII) is a pore-forming toxin of biomedical interest that belongs to the actinoporin protein family. Sticholysins are currently under examination as an active immunomodulating component of a vaccinal platform against tumoral cells and as a key element of a nucleic acids delivery system to cell cytosol. These proteins form pores in the plasma membrane leading to ion imbalance and cell lysis. However, the intracellular mechanisms triggered by actinoporins upon binding to membranes and its consequences for cell death are barely understood. Here, we have examined the cytotoxicity and intracellular responses induced by StII upon binding to human B-cell lymphoma Raji in vitro. StII cytotoxicity involves a functional actin cytoskeleton, induces cellular swelling, lysis and the concomitant release of cytosol content. In addition, StII induces calcium release mainly from the Endoplasmic Reticulum, activates Mitogen-Activated Protein Kinase ERK and impairs mitochondrial membrane potential. Furthermore, StII stimulates the expression of receptor interacting protein kinase 1 (RIP1), normally related to different forms of regulated cell death such as apoptosis and necroptosis. In correspondence, necrostatin-1, an inhibitor of this kinase, reduces StII cytotoxicity. However, the mechanism of cell death activated by StII does not involve caspases activation, typical molecular features of apoptosis and pyroptosis. Our results suggest that, beyond pore-formation and cell lysis, StII-induced cytotoxicity could involve other regulated intracellular mechanisms connected to RIP1-MEK1/2 –ERK1/2- pathways. This opens new perspectives and challenges the general point of view that these toxins induce a completely unregulated mechanism of necrotic cell death. This study contributes to a better understanding of the molecular mechanisms involved in toxin-cell interaction and the implications for cell functioning, with connotation for the exploitations of these toxins in clinical settings.

The commercial enzyme preparations Pectinex Ultra SP-L and Celluclast 1.5 L were used in the treatment of spent maqui berry pomace to improve the anaerobic methanogenic potential of the pomace. Two types of enzymatic treatment were evaluated, a pre-treatment prior to anaerobic methanisation and an enzymatic treatment during the methanisation process itself. Neither of the commercial enzyme preparations significantly improved the methanogenic potential when the enzymes were used for pre-treatment. However, methane production was observed to increase by 28% when the Pectinex Ultra SP-L enzyme preparation was used during the methanisation process compared with that of samples that were not treated with any enzymes. Both enzymatic preparations showed an increase in glucose content, yielding a 132% increase in glucose content when the Pectinex Ultra SP-L preparation was used and a 102% increase when the Celluclast 1.5 L preparation was used. Finally, the addition of Pectinex Ultra SP-L increased the solubilised material content by 24–34%, whereas the addition of Celluclast 1.5 L achieved a 34% increase in solubilisation when 2 mg of enzyme was added per gram of total solids; however, there was no significant improvement observed when the Celluclast 1.5 L was added at other ratios.

The current data presented correspond to the determination of inulin recovery from globe artichoke canned industry wastes. The discard was composed mainly by bracts with a small percentage of stems and receptacles. Artichoke discards (AD) were dehydrated by lyophilization or convective drying at different temperatures (40°C to 100°C). Inulin amount in extracts obtained using hydroalcoholic solvents (ethanol:water 75:25), which are applied for polyphenols recovery, was determined. After that, the sequential extraction of inulin with water and then with hydroalcoholic solvent was done. Finally, inulin content in lyophilized samples using different ethanol:water mixtures was determined. Inulin was determined by vanillin method and total phenolic compounds (TPC) by Folin-Ciocalteu method. From the lyophilized sample it is possible to obtain 3938.7 ± 169.1 mg inulin / 100 g AD dry basis (d.b.) and 2086.3 ± 120.7 mg TPC / 100 g AD d.b. While, from conventionally dried samples, the recovery of inulin can reach 4391.1 ± 208.2 mg inulin / 100 g AD d.b for samples dried at 60°C, but only 337.2 ± 25.9 mg TPC / 100 g AD d.b. was recovered at the same condition. Sequential extraction of lyophilized samples with water (95°C, 30 minutes) and ethanol:water 75:25 (40°C, 60 minutes) recovers in total 10907.3 mg inulin / 100 g AD and 2687.7 mg TPC / 100 g AD d.b. If the ethanol concentration decreases at 50% and the extraction is done only with the hydroalcoholic solvent, the inulin increases up to 5251.2 ± 257.4 mg inulin / 100 g AD d.b. This Data in Brief corresponds to an accompanying work to the article titled “Valorization of Globe Artichoke (Cynara scolymus) Agro-Industrial Discards, Obtaining an Extract with a Selective Effect on Viability of Cancer Cell Lines” published at Processes journal [1].

We studied the effect of both heat-drying and freeze-drying on the recovery of total phenolic compounds (TPCs) and antioxidant capacity from leaves of Peumus boldus Molina (Boldo), an endemic tree of Chile, using DPPH (2,2-diphenyl-1-picrylhydrazyl radical scavenging), FRAP (ferric reducing antioxidant power) and ORAC (oxygen radical absorbance capacity) methods. The results indicated that infusions prepared using commercial boldo tea bags had similar or higher TPCs, DPPH, FRAP and ORAC values in comparison with those of the infusions prepared using heat- or freeze-dried leaves. The extraction experiments showed that hydro-alcoholic mixtures are the best solvents to extract antioxidants from boldo leaves, favoring the use of freeze-dried leaves. Considering the alkaloid profile of the extracts of freeze-dried leaves and herbal tea bags, the latter exhibited higher amounts of the alkaloids tested, including boldine, which is well correlated with the results obtained using the ORAC method. These results indicate a great potential to develop commercial boldo extracts and could encourage improved applications of this endemic Chilean plant. (C) 2013 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

The data presented in this article are focused on thermal stability data of both juglone standard (in ethanol and methanol) and a natural extract containing juglone from lyophilized walnut green husk (in ethanol and methanol). On the other hand, we also show the data of the impact of three concentration technologies over the concentration yield of juglone from the natural extract in ethanol and methanol. All data presented are related with the information included in “Polyphenolic extracts of walnut (Juglans regia) green husk containing juglone inhibit the growth of HL-60 cells and induce apoptosis” Soto-Maldonado et al., 2019, where the discussion and interpretation of results can be found. Keywords: Thermal stability, Juglone, Concentration technologies, Hydroalcoholic extracts

Sticholysin II (St II) is a toxin from the sea anemona Stichodactyla helianthus that produces erythrocytes lysis at low concentration and its activity depends on the presence of calcium. Calcium may act modifying toxin interaction with erythrocyte membranes or activating cellular processes which may result in a modified St II lytic action. In this study we are reporting that, in the presence of external K + , extracellular calcium decreased St II activity on erythrocytes. On the other hand an increase of intracellular calcium promotes Sty II lytic activity. The effect of intracellular calcium was specifically studied in relation to membrane lipid translocation elicited by scramblases and how this action influence St II lytic activity on erythrocytes. We used 0.5 mmol/L calcium and 10 mmol/L A23187, as calcium ionophore, for scramblases activation and found increased St II activity associated to increase of intracellular calcium. N -ethyl maleimide (activator) and 4,4′-diisothiocyanatostilbene-2,2′-disulfonate (inhibitor) were used as scramblases modulators in the assays which produced an increase and a decrease of the calcium effect, respectively. Results reported suggest an improved St II membrane pore-forming capacity promoted by intracellular calcium associated to membrane phospholipids translocation.

Polyphenols content (as catechin equivalents) and tocopherol content were determined in borage defatted meal and borage oil, respectively. In addition, antioxidant activity of extracts obtained from borage defatted meal was evaluated. A cold pressing process was used for the extraction of Borago officinalis oil, resulting in a defatted meal (by-product). Polyphenols from this defatted borage meal were extracted using several solvents. An extract containing highly soluble solids and phenolic compounds with antioxidant activity (as free radical-scavenging, DPPH) was obtained when methanol was used. The tocopherol content was higher in oil extracted by cold pressing than in oil extracted with petroleum ether as organic solvent. An enzymatic treatment was applied (45 °C, 20% moisture, 0.25% E/S ratio, 1:1 Olivex:Celluclast enzymatic mixture) previously to borage oil extraction, which improved the antioxidant content in the borage defatted meal by three-folds, as compared to the values obtained by a nonenzyme-aided process.

Protein concentrates, produced by aqueous extraction and membrane filtration from Guevina avellana pressing cakes, were characterized with regard to nutritional and functional properties. The effect of a previous enzymatic treatment, carried out with the aim of enhancing oil extractability during pressing, was also evaluated. Thermal conditioning of the seeds, before pressing, influenced oil and protein extractability, as well as the nutritional quality and functional properties. The protein concentrates contained up to 65% protein with an in vitro apparent digestibility coefficient in the range 75–80%. They presented a reduced ability to bind water, but they retained almost up to ten times their weight of oil.

Background: Lactobacillus sp. are probiotic microorganisms, and some of them are able to produce conjugated linoleic acid (CLA) via the bio-hydrogenation of linoleic acid (LA). Both CLA and LA are polyunsaturated fatty acids commonly used in the prevention and control of cardiovascular disease, high cholesterol, and cancer, among other ailments. The carbon source is one variable that can affect the growth and characteristics of these bacteria. Molecules called prebiotics are known to benefit human health by stimulating the growth and activity of probiotic bacteria present in the intestinal microflora. The aim of this study was to evaluate how different oligosaccharides affect the growth and fatty acid profile of Lactobacillus plantarum (NRRL - B4496). L. plantarum cultivation was performed in Man-Rogosa-Sharpe (MRS) medium, and the original carbon source (glucose) in this medium was partially or totally replaced by an oligosaccharide (isomaltooligosaccharide (IMO) or gentiooligosaccharide (GTO)). Then, the biomass concentration and fatty acid profile were determined using spectrophotometry and gas chromatography, respectively. Results: When 50% of the glucose in the MRS medium was replaced with IMO, the maximum growth was 2.6 g/L at 37oC. Under the same culture conditions, the incorporation of GTO only produced 2 g/L of biomass. At 45oC, the growth of the bacterial culture was lower than that observed at 37oC, reaching only 0.4 g/L. When cultivated at 37oC in a mixture of glucose and GTO (1:1), CLA (34%, c9t11) was obtained from cells of L. plantarum . However, when the cultivation was performed at 45oC, CLA was not obtained. When IMO was used, differences in CLA content were not observed between L. plantarum cultivated with glucose or with IMO present; however, vaccenic acid was produced. Conclusions: Lactobacillus plantarum grow well when a mixture of IMO and glucose is used as the carbon source. However, this mixture does not improve the CLA content, most likely due to high enzymatic activity that promotes the conversion of CLA to vaccenic acid. Additionally, GTO is likely less readily metabolized by this strain. Thus, the enzymatic activity is likely lower and less CLA is converted to vaccenic acid, resulting in an accumulation of CLA.

The lipopolysaccharide (LPS) of Vibrio cholerae is considered one of the most important antigens from the point of view of immunogenicity in these bacteria. We have undertaken detoxification of this LPS by basic hydrolysis and the resultant amine groups were used for their conjugation to tetanus toxoid as carrier protein using carbodiimide-mediated coupling. The resulting conjugates were inoculated in Balb/c mice for immunogenicity studies. The anti-LPS IgG and vibriocidal antibodies were measured in serum. The antigenicity of this conjugated was evaluated by ELISA, with serums of humans vaccinated with a strain genetically modified. The conjugated elicited: high titers of IgG anti-LPS, high titers of vibriocidal antibodies and there was recognition of LPS by antibodies from cholerae immunised human serum. These results show that the conjugated LPS obtained by us, could be evaluated like a potential vaccine for human use.