By-product recovery of Opuntia spp. peels: Betalainic and phenolic profiles and bioactive properties

[EN] Opuntia spp. are a tropical and subtropical plant that provides both edible green steams and fruits; however, the processing of this fruits results in the accumulation of enormous amount of by-products that can be a source of bioactive and pigmented compounds. Herein, three cactus pear from the species Opuntia focus-indica var. sanguigna (OS) and gialla (OG) and Opuntia engelmannii (OE) were fully characterized regarding their phenolic and betalain composition and correlated with their antioxidant and antimicrobial activities. The hydroethanolic extracts of OE gave the highest amount of phenolic compounds isorhamentin-O-(deoxyhexosyl-hexoside) and betacianins (betanin); however, no betaxanthins were identified in this sample. This sample also revealed the lowest EC50 values in all the antioxidant activity assays. Regarding antimicrobial activity, the hydroethanolic extracts of all species revealed to be more active than ampicillin. The pivotal objective of this work was to focus on exploring by-product biocompounds and possible outputs, thus, we could suggest the use of these natural colorants with intrinsic antioxidant and antimicrobial activity, which would grant industries to produce cleaner label products with functional benefits.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2013) and L. Barros contract. This work is funded by the European Structural and Investment Funds (FEEI) through the Regional Operational Program North 2020, within the scope of Project NORTE-01-0145-FEDER-023289 (DeCodE) and ValorNatural (R). B. Melgar (No. 329930) also thanks CONACyT for his grant. The authors are grateful for a grant from the Serbian Ministry of Education, Sciences and Technological Development (no. 173032). The authors would also like to thank Dr. Carlos Aguiar for the botanical identification of these species.Melgar-Castañeda, B.; Dias, MI.; Ciric, A.; Sokovic, M.; Garcia-Castello, EM.; Rodríguez López, AD.; Barros, L.... (2017). By-product recovery of Opuntia spp. peels: Betalainic and phenolic profiles and bioactive properties. Industrial Crops and Products. 107:353-359. https://doi.org/10.1016/j.indcrop.2017.06.011S35335910

Ultrasound and Microwave Assisted Extraction of Opuntia Fruit Peels Biocompounds: Optimization and Comparison Using RSM-CCD

[EN] Ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) of bioactive compounds, peels from Opuntia engelmannii cultivar (cv.) Valencia were optimized by response surface methodology. Randomized extraction runs were performed for each of the technologies employed in order to build effective models with maximum (bioactive molecules content and yield) and minimum (antioxidant activity) responses. A 5-level, 4-factor central composite design was used to obtain target responses as a function of extraction time (t), solid to liquid ratio (S/L), methanol concentration (metOH), and temperature (T). Specific response optimization for each technology was analyzed, discussed, and general optimization from all the responses together was also gather. The optimum values for each factor were: t = 2.5 and 1.4 min, S/L = 5 and 5 g/L, metOH = 34.6 and 0% of methanol and T = 30 and 36.6 °C, achieving maximum responses of 201.6 and 132.9 mg of betalains/g, 13.9 and 8.0 mg of phenolic acids/g, 2.4 and 1.5 mg of flavonoids/g, 71.8% and 79.1% of extractable solid and IC50 values for the antioxidant activity of 2.9 and 3.6, for UAE and MAE, respectively. The present study suggested UAE as the best extraction system, in order to maximize recovery of bioactive compounds with a high antioxidant activity.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programmer PT2020 for financial support to CIMO (UID/AGR/00690/2019) and L. Barros and M.I. Dias also thank the national funding by FCT, P.I., through the institutional scientific employment program-contract. The authors are grateful to CONACyT for supporting B. Melgar with his doctoral grant (No. 329930). The authors specially thanks to Maria Luisa Ruiz and the "Laboratorio Agroalimentario de la Comunitat Valenciana" for allow the use of the microwave for the extractions. This work is also funded by the European Regional Development Fund (ERDF) through the Regional Operational Program North 2020, within the scope of Project Mobilizador Norte-01-0247-FEDER-024479: ValorNatural(R)Melgar-Castañeda, B.; Dias, MI.; Barros, L.; Ferreira, IC.; Rodríguez López, AD.; Garcia-Castello, EM. (2019). Ultrasound and Microwave Assisted Extraction of Opuntia Fruit Peels Biocompounds: Optimization and Comparison Using RSM-CCD. 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Subclinical Atherosclerosis Burden by 3D Ultrasound in Mid-Life: The PESA Study

BACKGROUND: Detection of subclinical atherosclerosis improves risk prediction beyond cardiovascular risk factors (CVRFs) and risk scores, but quantification of plaque burden may improve it further. Novel 3-dimensional vascular ultrasound (3DVUS) provides accurate volumetric quantification of plaque burden. OBJECTIVES: The authors evaluated associations between 3DVUS-based plaque burden and CVRFs and explored potential added value over simple plaque detection. METHODS: The authors included 3,860 (92.2%) PESA (Progression of Early Subclinical Atherosclerosis) study participants (age 45.8 ± 4.3 years; 63% men). Bilateral carotid and femoral territories were explored by 3DVUS to determine the number of plaques and territories affected, and to quantify global plaque burden defined as the sum of all plaque volumes. Linear regression and proportional odds models were used to evaluate associations of plaque burden with CVRFs and estimated 10-year cardiovascular risk. RESULTS: Plaque burden was higher in men (63.4 mm3 [interquartile range (IQR): 23.8 to 144.8 mm3] vs. 25.7 mm3 [IQR: 11.5 to 61.6 mm3] in women; p < 0.001), in the femoral territory (64 mm3 [IQR: 27.6 to 140.5 mm3] vs. 23.1 mm3 [IQR: 9.9 to 48.7 mm3] in the carotid territory; p < 0.001), and with increasing age (p < 0.001). Age, sex, smoking, and dyslipidemia were more strongly associated with femoral than with carotid disease burden, whereas hypertension and diabetes showed no territorial differences. Plaque burden was directly associated with estimated cardiovascular risk independently of the number of plaques or territories affected (p < 0.01). CONCLUSIONS: 3DVUS quantifies higher plaque burden in men, in the femoral territory, and with increasing age during midlife. Plaque burden correlates strongly with CVRFs, especially at the femoral level, and reflects estimated cardiovascular risk more closely than plaque detection alone. (Progression of Early Subclinical Atherosclerosis [PESA] Study; NCT01410318).The PESA study is cofunded equally by the Fundacion Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain, and Banco Santander, Madrid, Spain. The study also receives funding from the Institute of Health Carlos III (PI15/02019) and the European Regional Development Fund (ERDF). The CNIC is supported by the Ministry of Economy, Industry and Competitiveness (MINECO) and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (MINECO award SEV-2015-0505). Dr. Sanchez-Gonzalez is an employee of Philips Healthcare. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose. Stephen J. Nicholls, MD, served as Guest Editor for this paperS

Vascular Inflammation in Subclinical Atherosclerosis Detected by Hybrid PET/MRI

BACKGROUND: Atherosclerosis is a chronic inflammatory disease, but data on arterial inflammation at early stages is limited. OBJECTIVES: The purpose of this study was to characterize vascular inflammation by hybrid 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/magnetic resonance imaging (PET/MRI). METHODS: Carotid, aortic, and ilio-femoral 18F-FDG PET/MRI was performed in 755 individuals (age 40 to 54 years; 83.7% men) with known plaques detected by 2-/3-dimensional vascular ultrasound and/or coronary calcification in the PESA (Progression of Early Subclinical Atherosclerosis) study. The authors evaluated the presence, distribution, and number of arterial inflammatory foci (increased 18F-FDG uptake) and plaques with or without inflammation (coincident 18F-FDG uptake). RESULTS: Arterial inflammation was present in 48.2% of individuals (24.4% femorals, 19.3% aorta, 15.8% carotids, and 9.3% iliacs) and plaques in 90.1% (73.9% femorals, 55.8% iliacs, and 53.1% carotids). 18F-FDG arterial uptakes and plaques significantly increased with cardiovascular risk factors (p < 0.01). Coincident 18F-FDG uptakes were present in 287 of 2,605 (11%) plaques, and most uptakes were detected in plaque-free arterial segments (459 of 746; 61.5%). Plaque burden, defined by plaque presence, number, and volume, was significantly higher in individuals with arterial inflammation than in those without (p < 0.01). The number of plaques and 18F-FDG uptakes showed a positive albeit weak correlation (r = 0.25; p < 0.001). CONCLUSIONS: Arterial inflammation is highly prevalent in middle-aged individuals with known subclinical atherosclerosis. Large-scale multiterritorial PET/MRI allows characterization of atherosclerosis-related arterial inflammation and demonstrates 18F-FDG uptake in plaque-free arterial segments and, less frequently, within plaques. These findings suggest an arterial inflammatory state at early stages of atherosclerosis. (Progression of Early Subclinical Atherosclerosis [PESA]; NCT01410318).The PESA study is cofunded equally by the Centro Nacional de Investigaciones Cardiovasculares (CNIC) and Banco Santander. The study also receives funding from the Instituto de Salud Carlos III (PI15/02019) and the European Regional Development Fund (ERDF) “A way to make Europe.” The CNIC is supported by the Ministerio de Ciencia, Innovación y Universidades, and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-0505). Dr. Sanchez-González is an employee of Philips Healthcare. Dr. Bueno has received research funding from the Instituto de Salud Carlos III, Spain (PIE16/00021 & PI17/01799), AstraZeneca, Bristol-Myers Squibb, Janssen, and Novartis; has received consulting fees from AstraZeneca, Bayer, Bristol-Myers Squibb-Pfizer, and Novartis; and has received speaking fees or support for attending scientific meetings from AstraZeneca, Bayer, Bristol-Myers Squibb-Pfizer, Novartis, and MEDSCAPE-the heart.org.S

Accurate quantification of atherosclerotic plaque volume by 3D vascular ultrasound using the volumetric linear array method.

Direct quantification of atherosclerotic plaque volume by three-dimensional vascular ultrasound (3DVUS) is more reproducible than 2DUS-based three-dimensional (2D/3D) techniques that generate pseudo-3D volumes from summed 2D plaque areas; however, its accuracy has not been reported. We aimed to determine 3DVUS accuracy for plaque volume measurement with special emphasis on small plaques (a hallmark of early atherosclerosis). The in vitro study consisted of nine phantoms of different volumes (small and medium-large) embedded at variable distances from the surface (superficial vs. >5 cm-depth) and comparison of 3DVUS data generated using a novel volumetric-linear array method with the real phantom volumes. The in vivo study was undertaken in a rabbit model of atherosclerosis in which 3DVUS and 2D/3D volume measurements were correlated against gold-standard histological measurements. In the in vitro setting, there was a strong correlation between 3DVUS measures and real phantom volume both for small (3.0-64.5 mm(3) size) and medium-large (91.1-965.5 mm(3) size) phantoms embedded superficially, with intraclass correlation coefficients (ICC) of 0.99 and 0.98, respectively; conversely, when phantoms were placed at >5 cm, the correlation was only moderate (ICC = 0.67). In the in vivo setting there was strong correlation between 3DVUS-measured plaque volumes and the histological gold-standard (ICC = 0.99 [4.02-92.5 mm(3) size]). Conversely, the correlation between 2D/3D values and the histological gold standard (sum of plaque areas) was weaker (ICC = 0.87 [49-520 mm(2) size]), with large dispersion of the differences between measurements in Bland-Altman plots (mean error, 79.2 mm(2)). 3DVUS using the volumetric-linear array method accurately measures plaque volumes, including those of small plaques. Measurements are more accurate for superficial arterial territories than for deep territories.S

Bioactive characterization of Persea americana Mill. by-products: A rich source of inherent antioxidants

[EN] Avocado (Persea americana Mill.) is a worldwide consumed fruit, with great interest for cosmetic and pharmaceutical industries; however, 30% of avocado fruits are bio-wastes (peels and kernels), converting them into a potential source of bioactive compounds, such as phenolic compounds. Therefore, the hydroethanolic extracts of peels and kernels of Persea america Mill. var. Hass were analysed regarding their individual phenolic profile by HPLC-DAD/ESI-MS and correlated with their antioxidant, antimicrobial and cytotoxic activities. Avocado by-products presented a very distinct phenolic profile, presenting higher concentration in peels (227.9 mg/g of extract for total phenolic content), mainly in (epi)catechin derivatives (175 mg/g of extract), followed by chlorogenic derivatives (42.9 mg/g of extract). In this study hydrophilic and lipophilic antioxidant assays were performed together for the first time in P. americana by-products, and although kernels showed a great antioxidant potential (EC50 values ranging from 18.1 to 276 mu g/mL), peels presented the highest potential (EC50 ranging from 11.7 to 152 mu g/mL), mainly due to the presence of phenolic compounds, and an overall better performance in the antibacterial assays. Further studies needs to be conducted to better understand the correlation between the presence of phenolic compounds and bioactivities, however, the main objective is to implement these biocompounds in different products and industries, due to results obtained, P. americana peels could be a great alternative in the substitution of synthetic antioxidants.The authors are grateful to the Foundation for Science and Technology(FCT, Portugal) and FEDER under Program PT2020 for financial support to CIMO (UID/AGR/00690/2013) and L. Barros contract. The authors would like to thank the Interreg Espana-Portugal for financial support through the project 0377_Iberphenol_6_E. B. Melgar thanks CONACyT for his grant (No. 329930). The authors are also grateful to the Serbian Ministry of Education, Science and Technological Development, grant number 173032 for financial support.Melgar-Castañeda, B.; Dias, MI.; Ciric, A.; Sokovic, M.; Garcia-Castello, EM.; Rodríguez López, AD.; Barros, L.... (2018). Bioactive characterization of Persea americana Mill. by-products: A rich source of inherent antioxidants. Industrial Crops and Products. 111:212-218. https://doi.org/10.1016/j.indcrop.2017.10.024S21221811

Probiotic-Derived Polyphosphate Enhances the Epithelial Barrier Function and Maintains Intestinal Homeostasis through Integrin–p38 MAPK Pathway

Probiotics exhibit beneficial effects on human health, particularly in the maintenance of intestinal homeostasis in a complex manner notwithstanding the diversity of an intestinal flora between individuals. Thus, it is highly probable that some common molecules secreted by probiotic and/or commensal bacteria contribute to the maintenance of intestinal homeostasis and protect the intestinal epithelium from injurious stimuli. To address this question, we aimed to isolate the cytoprotective compound from a lactobacillus strain, Lactobacillus brevis SBC8803 which possess the ability to induce cytoprotective heat shock proteins in mouse small intestine. L. brevis was incubated in MRS broth and the supernatant was passed through with a 0.2-µm filter. Caco2/bbe cells were treated with the culture supernatant, and HSP27 expression was evaluated by Western blotting. HSP27-inducible components were separated by ammonium sulfate precipitation, DEAE anion exchange chromatography, gel filtration, and HPLC. Finally, we identified that the HSP27-inducible fraction was polyphosphate (poly P), a simple repeated structure of phosphates, which is a common product of lactobacilli and other bacteria associated with intestinal microflora without any definitive physiological functions. Then, poly P was synthesized by poly P-synthesizing enzyme polyphosphate kinase. The synthesized poly P significantly induced HSP27 from Caco2/BBE cells. In addition, Poly P suppressed the oxidant-induced intestinal permeability in the mouse small intestine and pharmacological inhibitors of p38 MAPK and integrins counteract its protective effect. Daily intrarectal administration of poly P (10 µg) improved the inflammation grade and survival rate in 4% sodium dextran sulfate-administered mice. This study, for the first time, demonstrated that poly P is the molecule responsible for maintaining intestinal barrier actions which are mediated through the intestinal integrin β1-p38 MAPK