By-product Extracts Research Articles

Fish scales : Waste processing as a potential source of bioactive compounds

The rise of fish processing over the years has led to an upsurge of by-products like fish scales, bones and skin which are often considered as trash and discarded. Study on two most common carp fish in Indian freshwater, Catla catla and Labeo rohita revealed some valuable by- products from nonedible fish scales such as type I collagen, gelatin, hydroxyapatite, chitin and chitosan. The remarkable antioxidant effects of fish gelatin isolated from fish scale is of great pharmaceutical importance in addition to type I collagen which is utilized for implants to culture skin cells or as drug carrier for restoration of skin. Collagen has haemostatic characteristic and facilitate blood coagulation as well as tissue repair. A natural biocompatible component of fish scale that coexists with collagen protein is hydroxyapatite. Hydroxyapatite is also used in controlled drug release by pharmaceutical industry and hip replacement surgery. Currently chitosan obtained from chitin present in fish by-product is gaining popularity as a potential drug candidate and gene carrier for anticancer chemotherapy. Taken altogether, our study highlights the importance and method of extraction of different by-products of Indian fresh water fishes in health science.

Actividades antimicrobianas y antifúngicas de los extractos alcohólicos de Passiflora edulis y Citrus x sinensis

In the present work, the inhibitory power of the alcoholic extracts of the agro-industrial by-products of orange and passion fruit was studied against four bacteria: Listeria monocytogenes, Streptococcus mutans, Salmonella spp., Escherichia coliand two fungi: Penicilliumsp, and Rhizopus spp. The alcoholic extracts of orange and passion fruit peels in concentrations of 0,05 and 0,1% were applied to strains of the six microorganisms and the zone of inhibition and the growth curve along 24 h were determined.The results showed that the highest concentration of the extracts (0,1%) of both fruits formed inhibition zones of larger diameter. The bacteria were more resistant to orange extracts compared to passion fruit extracts, with complete inhibition at 24 and 6 h, respectively. On the other hand, the complete inhibition of the fungi was after 4 hours of action of extracts of the two fruits.

Characterization of Poly(vinyl alcohol)/gelatin films made with winery solid by-product (vinasse) extract

The aim of this study is to examine the effect of grape pomace extract (GP) on the technological, functional and structural properties of Poly (vinyl alcohol) (PVA)/fish gelatin (FG) blend films. The addition of different ratios of GP (0 %, 0.5 %, 1 %, 1.5 % and 2 %) to PVA/FG edible films improved their rheological properties. The complex viscosity value increased exponentially when 2 % GP was added to the composite films compared to samples without any added GP. FTIR results showed that PVA and FG were able to interact with GP. The surface morphology indicated that addition of GP enhanced the intermolecular polymer interactions of the PVA-FG-GP combination. Atomic force microscopy (AFM) revealed that the films with GP had homogenous and smoother surfaces. X-ray diffraction (XRD) results confirmed that the FG and PVA chains interacted with GP, causing structural repositioning. Further confirmation of the effective interaction between PVA, FG and GP came from the decrease in crystallinity as the concentration of GP was increased. The melting temperature (Tm) was enhanced with the addition of GP. The combination of GP with PVA/FG films improved the plasticizer and surfactant properties thereby enhancing the flexibility of the films. The water solubility parameter was improved with the addition of GP without compromising the barrier properties. The antioxidant activity of the films increased significantly with the addition of GP. A GP-enriched PVA/FG film can be used as an edible film for food packaging purposes.

Bioactive Profile of Distilled Solid By-Products of Rosemary, Greek Sage and Spearmint as Affected by Distillation Methods.

By-products of essential oils (EOs) in the industry represent an exploitable material for natural and safe antioxidant production. One representative group of such by-products is distilled solid residues, whose composition is properly modulated by the distillation method applied for the recovery of EOs. Recently, in terms of Green Chemistry principles, conventional extraction and distillation processes are considered outdated and tend to be replaced by more environmentally friendly ones. In the present study, microwave-assisted hydro-distillation (MAHD) was employed as a novel and green method for the recovery of EOs from three aromatic plants (rosemary, Greek sage and spearmint). The method was compared to conventional ones, hydro-distillation (HD) and steam-distillation (SD), in terms of phytochemical composition of distilled solid residues, which was estimated by spectrophotometric and chromatographic methods. Total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity (ABTS, DPPH and FRAP) results highlighted the distilled solid residues as good sources of antioxidants. Moreover, higher antioxidant activity was achieved for MAHD extracts of solid residues in comparison to HD and SD extracts. A metabolomics approach was carried out on the methanolic extracts of solid residues obtained by different distillation methods using LC-MS analysis followed by multivariate data analysis. A total of 29 specialized metabolites were detected, and 26 of them were identified and quantified, presenting a similar phenolic profile among different treatments, whereas differences were observed among different species. Rosmarinic acid was the most abundant phenolic compound in all extracts, being higher in MAHD extracts. In rosemary and Greek sage extracts, carnosol and carnosic acid were quantified in significant amounts, while trimers and tetramers of caffeic acid (salvianolic acids isomers) were identified and quantified in spearmint extracts, being higher in MAHD extracts. The obtained results pointed out that MAHD extracts of distilled solid by-products could be a good source of bioactives with potential application in the food, pharmaceutical and cosmetic industries, contributing to the circular economy.

Process Optimization of Phytoantioxidant and Photoprotective Compounds from Carob Pods (Ceratonia siliqua L.) Using Ultrasonic Assisted Extraction Method.

The current study first describes the extraction of phytoantioxidant polyphenols from Carob byproducts (pods) using maceration and heating-assisted extraction as traditional methods and ultrasonic-assisted extraction (UAE) as an innovative method to determine the most efficient extraction process in terms of four targeted responses: total phenolic content (TPC), antioxidant activities (TAC and DPPH), and photoprotective properties as measured by the sun protection factor (SPF). Second, we used response surface methodology (RSM) with a central composite rotatable design (CCDR) approach to investigate the influence of process variables (extraction time, extraction temperature, and solvent concentration) on UAE, which was found to be the most effective extraction technique in our study. Carob byproduct extracts had a TPC ranging from 6.21 to 21.92 mg GAE/g dw, a TAC ranging from 22.00 to 49.30 mg AAE/g dw, DPPH scavenging activity ranging from 56.35 to 90.50%, and SPF values ranging from 8.62 to 22.37. The optimal UAE conditions for maximum TPC, TAC, DPPH, and SPF responses were determined to be 38.90% ethanol, 53.90 °C, and 50.92 min. Using Carob as a source for sustainable and bioactive products in conjunction with optimized UAE is a promising contribution to the cosmetic industry that will help to strengthen the concept of environmentally-friendly "green chemistry". Given that Carob pulp or seeds are considered food byproducts, the research presented here encourages the use of these agri-food waste materials in cosmetics.

Incorporation of phenolic extracts from different by-products in yoghurts to create fortified and sustainable foods

This work aimed to study and compare the effect of the incorporation of agro-industrial by-products (chestnut shell, grapeseed, and pomegranate peel) into yoghurts to fortify them while assessing their potential to replace synthetic preservatives. From each by-product, phenolic extracts were obtained and characterized. All extracts demonstrated antioxidant and antibacterial properties, and the capacity to inhibit α-amylase. Chestnut shell extract stood out regarding antioxidant capacity, displaying values of 1128 and 972 mgTrolox∙gextract−1, for the assays with DPPH and ABTS, respectively. Ten yoghurts were produced (negative control, positive control with 0.1% of sorbic acid, two for each extract with 0.1% and 0.2% of extract, a mixture of extracts and a mixture of extracts with sorbic acid), and stored at 4 °C. The incorporation of the extracts into the yoghurts maintained their physical-chemical properties and microbiological safety. The samples inhibited the growth of Escherichia coli and Staphylococcus aureus. Oxidative analysis proved that higher concentrations of extract had similar results to synthetic antioxidants. The results showed the viability to fortify yoghurts with the incorporation of by-product extracts, developing a value-added food. Furthermore, revealed the possibility of these extracts replacing synthetic preservatives and antioxidants.

Effects of Tomato Paste By-Product Extract on Growth Performance and Blood Parameters in Common Carp (Cyprinus carpio).

This research examined different growth performances and blood parameters of common carp (Cyprinus carpio) consuming diets supplemented with tomato paste by-product extract (TPE). Five diets with different concentrations of TPEs, 0% (TPE0) 0.5% (TPE0.5), 1% (TPE1), 2% (TPE2), and 5% (TPE5) were supplied to 300 common carp (8.38 ± 0.18 g) (60 fish per group) each day during the 60-day feeding trial. The relative and specific growth rates of fish-fed supplemental diets increased significantly, while the feed conversion ratio significantly decreased (p < 0.05). TPE considerably increased the erythrocyte count (RBC), hemoglobin content (Hb), and hematocrit (Hct) (p < 0.05), according to hematological analyses of blood samples collected after the feeding experiment. The blood biochemical findings indicate that using 1% or more extracts considerably reduced the serum glucose, cholesterol, and triglyceride ratios while significantly increasing the total protein, albumin, and globulin ratios in common carp (p < 0.05). Based on the findings of the study, it was concluded that the 2% extract generated from tomato paste by-products in common carp diets could be utilized as a growth-promoting product without any negative effects on blood parameters linked to feeding in carp.

Optimization of bacterial cellulose production from prickly pear peels and its ex situ impregnation with fruit byproducts for antimicrobial and strawberry packaging applications

Bacterial cellulose (BC) is currently among the most promising natural polymers. However, the production costs and biological inactivity are still challenges. The current study exploited the enzymatically hydrolyzed prickly pear peels (PPP) for BC production, which supported about 2.94 g/L as the sole production medium. The BC production was further optimized through a central composite design, where the maximum BC production was 6.01 g/L at 68 % PPPE at pH 4 after 11 days of incubation at 20 °C. The produced BC was characterized by FT-IR spectroscopy, XRD, and SEM analysis, and the results showed that PPPE is a promising carbon source for pure BC production. The BC membrane was separately loaded with several fruit byproduct extracts to enhance its biological activity for multiple applications. BC loaded with pomegranate peel extract (BC/PPE) revealed significant broad-spectrum antimicrobial activity, followed by BC loaded with pomegranate molasses (BC/PM). The BC/PPE membrane enhanced the shelf-life storage of strawberry fruits by about 5 days, with a reduction in the fruits' weight loss of 15 % compared to the uncovered group. The current study revealed the successful application of PPE for sustainable BC production with its packaging potential for enhancing strawberry shelf-life when loaded with PPE or PM.

Anti-Inflammatory and Antimicrobial Activities of Portuguese Prunus avium L. (Sweet Cherry) By-Products Extracts.

The bioactivity of natural by-products in food and pharmaceutical applications is the subject of numerous studies. Cherry production and processing generates large amounts of biowaste, most of which is not used. The recovery of these by-products is essential for promoting the circular economy and to improving sustainability in the food industry. In this work, we explored the anti-inflammatory and antimicrobial potential of two different extracts from stems, leaves, and flowers of Portuguese cherries. The anti-inflammatory potential was studied on lipopolysaccharide (LPS)-stimulated mouse macrophages (RAW 264.7) by evaluating the effect of by-products on cellular viability and nitric oxide (NO) production. Disc diffusion and minimum inhibitory concentration (MIC) were used to determine antimicrobial activity. The cherry by-products had no cytotoxic effect on RAW 264.7 cells, and were able to inhibit nitrite production in a dose-dependent manner. Moreover, all aqueous infusions showed good antioxidant activity against NO radicals. Moreover, leaf extracts showed the best activity against most of the strains studied. The results revealed, for the first time, interesting anti-inflammatory and antimicrobial properties of cherry by-products. This could potentially be of interest for their therapeutic use in the treatment of inflammation-related diseases or in controlling the growth of microorganisms.

Techno-economic strategies for improving economic viability of β-carotene extraction using natural oil and supercritical solvent: A comparative assessment

Dunaliella salina microalgae is a third-generation feedstock that is both thermophilic and halophilic and can be used to produce nutritious food supplements such as β-carotene. Although several techno-economic studies have been carried out to produce the pigment, most of them considered traditional synthetic chemicals such as hexane, acetone, and petroleum ether as solvents for extracting β-carotene from D. salina. In this study, techno-economic assessment is carried out with the aim of producing food-grade products for human consumption via greener methods of D. salina cultivation, harvesting, and extraction. The techno-economic assessment of the extraction of β-carotene and by-products using natural and edible corn oil and supercritical CO2 reveal that the processes are economically feasible, with a payback time of 5.9 y and 2.7 y (for corn oil and SC-CO2 methods), respectively. The ROIs for both methods are also positive, that is, 16.9 % and 37.1 %, respectively and greater than the prevailing interest rates in most countries. Sensitivity analyses show that the payback time is most sensitive to the yield of β-carotene, its production output, and its selling price. This assessment shows that food-grade β-carotene can be produced in bulk quantity from D. salina (as an alternative to other sources such as carrots, tomatoes, pumpkins, etc.) in order to satisfy the growing demands of nutritional markets.

Cardioprotective Effects of Grapefruit IntegroPectin Extracted via Hydrodynamic Cavitation from By-Products of Citrus Fruits Industry: Role of Mitochondrial Potassium Channels

Citrus flavonoids are well-known for their beneficial effects at the cardiovascular and cardio-metabolic level, but often the encouraging in vitro results are not confirmed by in vivo approaches; in addition, the clinical trials are also inconsistent. Their limited bioavailability can be, at least in part, the reason for these discrepancies. Therefore, many efforts have been made towards the improvement of their bioavailability. Hydrodynamic cavitation methods were successfully applied to the extraction of byproducts of the Citrus fruits industry, showing high process yields and affording stable phytocomplexes, known as IntegroPectin, endowed with great amounts of bioactive compounds and high water solubility. The cardioprotective effects of grapefruit IntegroPectin were evaluated by an ex vivo ischemia/reperfusion protocol. Further pharmacological characterization was carried out to assess the involvement of mitochondrial potassium channels. Grapefruit IntegroPectin, where naringin represented 98% of the flavonoids, showed anti-ischemic cardioprotective activity, which was better than pure naringenin (the bioactive aglycone of naringin). On cardiac-isolated mitochondria, this extract confirmed that naringenin/naringin were involved in the activation of mitochondrial potassium channels. The hydrodynamic cavitation-based extraction confirmed a valuable opportunity for the exploitation of Citrus fruits waste, with the end product presenting high levels of Citrus flavonoids and improved bioaccessibility that enhances its nutraceutical and economic value.

Sustainable Development and Storage Stability of Orange By-Products Extract Using Natural Deep Eutectic Solvents

The citrus industry produces large amounts of waste rich in bioactive compounds that have important effects on human health. Their extraction was performed using organic solvents, and a greener alternative to those solvents are natural deep eutectic solvents (NADES). The present study aimed to obtain and optimize extracts rich in polyphenols and flavonoids from orange peels using NADES and monitor polyphenol stability in the extracts for 30 days. The software COSMOtherm (conductor-like screening model) was used to screen fourteen NADES. The most promising solvents were lactic acid:glucose (LA:Glu) with an extraction yield of 1932 ± 7.83 mgGAE/100 gdw for TPC (total polyphenol content) and 82.7 ± 3.0 mg/100 gdw for TFC (total flavonoid content) and in the case of L-proline:malic acid (LP:MA) was 2164 ± 5.17 mgGAE/100 gdw for TPC and 97.0 ± 1.65 mg/100 gdw for TFC. The extraction process using LA:Glu and LP:MA was optimized, and the results showed that the selected variables (%NADES, solid:liquid ratio, and extraction time) had a significant influence on the extraction of TPC and TFC. Results showed that NADES improve the stability of TPC. These findings revealed that NADES are efficient for the extraction of bioactive compounds from orange by-products, and these extracts can represent an alternative for the food industry to enrich food products with natural ingredients.

Cellular antioxidant and viability efficacy of Harpephyllum caffrum peel and Syzygium guineense seed extracts

Crude phenolic extracts of indigenous sub-Saharan fruit byproducts have potent antioxidant activity. Purification of these extracts and evaluation of their antioxidant activity and viability using appropriate biological models, has, however, not yet been completed. The current study quantitatively evaluated the phenolic composition and in vitro antioxidant activity of crude and purified extracts (PE) of Harpephyllum caffrum peel (HCP) and Syzygium guineense seed (SGS), and cellular antioxidant and viability efficacy of the PE. Phenols were extracted by 60% ethanol (v/v) solvent system and purified using XAD7HP macroporous adsorption resin. The UPLC/Q-TOF-MS was used for the characterization and identification of phenols. Cellular antioxidant activity (CAA) assay was applied to assess the antioxidant efficacy and cytotoxicity of the PE. Analysis of variance of data was done using a generalized linear mixed model with fruit type, extract purity and their interaction as fixed effects. Purification increased (P ≤ 0.05) HCP total phenolic concentration (TPC) by over 200%, while SGS TPC decreased (P ≤ 0.05) by 20%. Regardless of fruit type, PE had higher (P ≤ 0.05) quantities of proanthocyanidins and anthocyanins than crude extracts. The HCP-PE had greater (P ≤ 0.05) in vitro antioxidant activity than the other extracts (P ≤ 0.05). Cellular antioxidant activity of HCP-PE was comparable to that of sodium metabisulphite (P > 0.05). Also, HCP-PE had lower (P ≤ 0.05) cytotoxic effects than SGS and sodium metabisulphite with increasing antioxidant concentration. It was concluded that HCP-PE is a potential source of safe natural antioxidants for nutraceutical applications.

Antioxidant Capacity, Vitamin C and Polyphenol Profile Evaluation of a Capsicum chinense By-Product Extract Obtained by Ultrasound Using Eutectic Solvent.

Habanero pepper leaves and stems (by-products) have been traditionally considered waste; however, bioactive compounds such as polyphenols, vitamin C and carotenoids have been identified that can be used for formulation of nutraceuticals or functional foods. Furthermore, the extraction of these bioactive compounds by using environmentally friendly methods and solvents is desirable. Thus, the aim of this study was to assess the antioxidant capacity, total polyphenol content (TPC), the phenolic profile and vitamin C content in extracts obtained from by-products (stems and leaves) of two varieties (Mayapan and Jaguar) of habanero pepper by ultrasound-assisted extraction (UAE) using natural deep eutectic solvents (NADES). The results showed that NADES leads to extracts with significantly higher TPC, higher concentrations of individual polyphenols (gallic acid, protocatechuic acid, chlorogenic acid, cinnamic acid, coumaric acid), vitamin C and, finally, higher antioxidant capacity (9.55 ± 0.02 eq mg Trolox/g DM) than UAE extraction performed with methanol as the solvent. The association of individual polyphenols with NADES was confirmed by principal component analysis (PCA). Overall, NADES is an innovative and promising “green” extraction technique that can be applied successfully for the extraction of phenolic compounds from habanero pepper by-products.

Food Industry Byproducts as Starting Material for Innovative, Green Feed Formulation: A Sustainable Alternative for Poultry Feeding.

Rising global populations and enhanced standards of living in so-called developing countries have led to an increased demand of food, in particular meat, worldwide. While increasing the production of broiler meat could be a potential solution to this problem, broiler meat is plagued by health concerns, such as the development of antimicrobial resistance and lower meat quality. For this reason, the supplementation of poultry feed with vitamins and antioxidant compounds, such as polyphenols, has become an attractive prospect for research in this sector. Such supplements could be obtained by extraction of agricultural byproducts (in particular, grape pomaces and artichoke leaves and bracts), thus contributing to reductions in the total amount of waste biomass produced by the agricultural industry. In this review, the effects of poultry feed supplementation with bioactive extracts from grape pomace (skins and/or seeds), as well as extracts from artichoke leaves and bracts, were explored. Moreover, the various methods that have been employed to obtain extracts from these and other agricultural byproducts were listed and described, with a particular focus on novel, eco-friendly extraction methods (using, for example, innovative and biocompatible solvents like Deep Eutectic Solvents (DESs)) that could reduce the costs and energy consumption of these procedures, with similar or higher yields compared to standard methods.

Chemical Composition and Valorization of Broccoli Leaf By-Products (Brassica oleracea L. Variety: Italica) to Ameliorate Reno-Hepatic Toxicity Induced by Gentamicin in Rats

Broccoli (Brassica oleracea) is reported to possess antioxidant activity that could potentially prevent oxidative damage to tissues caused by many diseases. In the present study, we investigated the preventive effect of broccoli leaf by-product extract (BL) on gentamicin-induced renal and hepatic injury by measuring tissue antioxidant activities and morphological apoptotic changes. Broccoli leaf was thoroughly extracted with 70% methanol to yield the total methanol extract (TME). The total phenolic content (TPC) was determined. Thirty male rats were divided into five groups (six animals/group). Group I received phosphate-buffered saline orally, while group II was treated with gentamicin (100 mg/kg i.p. intraperitoneal) for ten days. Group III and group IV animals were given BL (200 mg/kg and 400 mg/kg, respectively) plus gentamicin treatment. Group V received L-cysteine (1 mmole/kg) plus gentamicin. Antioxidant and biochemical parameters, such as transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase (ALP), creatinine, and urea, and mRNA expression levels of tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), and nuclear factor kappa B (NFkB) were determined in various groups, along with the quantification of inflammatory and apoptotic cells in hepatic and renal tissues. Malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) levels were determined in liver and renal samples. Histopathological studies of the liver and kidneys were also carried out. The TME was subjected to various and repeated techniques of chromatography to yield caffeic acid, gallic acid, and methyl gallate. The TPC was 6.47 mg Gallic Acid Equivalent/g of dry extract. Gentamicin increased the levels of serum AST, ALT, ALP, creatinine, and urea. The MDA and GSH contents and theactivity levels of the antioxidant enzyme SOD decreased in liver and kidney samples with gentamicin administration. BL administration dose-dependently prevented the alteration in biochemical parameters and was supported by low levels of tubular and glomerular injuries induced by gentamicin. This study valorizes the potential of BL as a preventive candidate in cases of gentamicin-induced liver and kidney toxicity and recommends further clinical studies using BL to validate its utilization for human consumption and as a source of phenolics for nutraceutical and pharmaceutical purposes.

A grapevine by-product extract enriched in oligomerised stilbenes to control downy mildews: focus on its modes of action towards &lt;i&gt;Plasmopara viticola&lt;/i&gt;

Natural extracts, and particularly plant by-product extracts, can represent an eco-friendly alternative to synthetic pesticides to control crop diseases. We produced an extract from a mix of grapevine trunk and roots that contain a high amount of complex stilbenes (grapevine phytoalexins), especially ε- and r-viniferins. This extract conferred protection to grapevines against Plasmopara viticola (the causal agent of downy mildew) by displaying antimicrobial activities towards zoospore mobility and sporulation and by stimulating plant defences. From the perspective of its application in the field, a formulated preparation of the extract was proposed using polysorbate and sophorolipids. The formulated extract reduced the development of various oomycetes impacting grapevine, potato, tomato and melon in semi-controlled conditions. Thus, such grapevine extract constitutes a promising strategy to protect major cultivated plants against downy mildews.

In Vitro Assessment of Antiproliferative Activity and Cytotoxicity Modulation of Capsicum chinense By-Product Extracts

Capsicum chinense J., also known locally as habanero pepper, is a medicinal herb known for its pharmacological properties. Its properties are attributed to the capsaicinoids and polyphenols found in its fruit and polyphenols in its by-products. The anticancer potential of C. chinense by-products remains unexplored. This study aimed to evaluate the antiproliferative activity and modulation of the cytotoxicity of extracts obtained from C. chinense by-products of plants grown on black and red soils of Yucatan, Mexico. Dry by-product extracts were obtained using maceration, a Soxhlet, and supercritical fluid extraction. In vitro antiproliferative activity and cytotoxicity modulation were evaluated by the sulforhodamine B method. The extract of leaves of plants grown on black soil obtained by maceration displayed selective high cytotoxicity against colorectal cancer cells, IC50 HCT–15 = 16.23 ± 2.89 µg mL−1. The leaf and stem extracts of plants grown on red soil obtained by maceration potentiated the vinblastine’s effect against parental breast cancer cells, MCF–7/Sens, with a reversion factor of 362.50-fold. Additionally, the extract of stems from plants grown on black soil obtained by supercritical fluid extraction and all the by-product extracts from plants grown on black soil obtained through maceration increased the effect of vinblastine against MCF–7/Vin+ with a reversion factor from 5.06- to 7.78-fold. These results highlight the anticancer potential of C. chinense by-products.

Pomegranate (Punica granatum) By-Product Extract Influences the Oxylipids Profile in Primary Bovine Aortic Endothelial Cells in a Model of Oxidative Stress

Aerobic metabolism produces reactive oxygen species (ROS) as a natural by-product that can play a significant role in cell signaling and homeostasis. Excessive and uncontrolled production of ROS, however, can lead to oxidative stress that causes damage to immune cells and is related to several diseases in dairy cattle. Endothelial cells are essential for optimal immune and inflammatory responses but are especially sensitive to the damaging effects of ROS. Accordingly, investigating antioxidant strategies that can mitigate the detrimental impact of ROS on endothelial functions could impact compromised host defenses that lead to increased disease susceptibility. The objective of this study was to test the antioxidant effect of different concentrations (20, 40, 60, 80 μg/ml) of pomegranate by-product extract (PBE) on bovine aortic endothelial cells (BAECs). A model of oxidative stress was developed using in vitro exposure of BAEC to 2,2′-azobis (2-amidinopropane) dihydrochloride (AAPH) to induce the formation of ROS. The BAEC were then analyzed for cell viability, ROS production, fatty acids profile, and oxylipids formation. The BAECs viability did not change after different concentrations of PBE and remained up to 80% over control; whereas, intracellular ROS showed a reduction passing from 20 to 50% with increasing PBE concentration from 20 to 80 μg/ml, respectively. The PBE extract clearly demonstrated efficacy in reducing the concentrations of pro-inflammatory oxylipids with a concomitant enhancement of anti-inflammatory oxylipids. In particular, the pro-inflammatory 13-hydroxyoctadecadienoic acid and its derived anti-inflammatory 13-hydroperoxoctadecaienoic acid were found lower and higher, respectively, in PBE+AAPH treated cells than AAPH treatment. Data from the present study support in vivo future experimental use of pomegranate by-product extract to study its potential beneficial effect against oxidative stress conditions in dairy cattle.

Antibacterial and antimycobacterial activity of white shrimp (Litopenaeus vannamei) exoskeleton and cephalothorax by-products extracts: fatty acids profile of the active hexanic shrimp cephalothorax extract

The objective of this study was to evaluate the antibacterial and antimycobacterial potential of the by-products of white shrimp (Litopenaeus vannamei). Sonora, México is the second shrimp producer state. The following extracts were obtained: exoskeleton hexanic, methanolic and acqueous extracts (ExHex, ExMe, ExAc); and cephalothorax hexanic, acetonic and methanolic extracts (CeHex, CeAce, CeMe). Antibacterial effect was determined by the broth microdilution method against Gram-positive bacteria: Enterococcus faecalis American Type Culture Collection (ATCC) 51299, Staphylococcus aureus ATCC 25293, and Staphylococcus epidermidis; Gram-negative bacteria: Escherichia coli ATCC 25922, Klebsiella pneumoniae, Pseudomonas aeruginosa ATCC 10145, and Salmonella typhimurium; and Mycobacterium bovis bacillus Calmette-Guérin (M. bovis BCG) Danish strain. CeHex resulted active against all Gram-positive and Gram-negative bacteria (MIC50= 400 ug mL-1) and against M. bovis BCG (MIC100= 250 ug mL-1). Gas chromatography (GC) of CeHex identified oleic, linoleic, palmitic, stearic, behenic, palmitoleic and linolenic fatty acids. The strong antibacterial activity of CeHex and the identification of its main chemical constituents justify further studies on the clinical applications of this marine by-product.