Fish Protein Hydrolysate from Sulfated Polysaccharides Extraction Residue of Tuna Processing By-Products with Bioactive and Functional Properties

The ethanol-induced precipitation after enzymatic hydrolysis commonly used for sulfated polysaccharide extraction from marine resources wastes a large amount of proteins. Here, possible extraction of fish protein hydrolysates (FPH) from the ethanol residue of sulfated polysaccharide precipitation from head, bone, and skin of skipjack tuna is investigated. Antioxidant, antibacterial, angiotensin I-converting enzyme (ACE) inhibitory activities and functional properties of the recovered FPHs are also evaluated. A degree of hydrolysis of 40.93, 38.13, and 37.23 is achieved for FPH from head, bone, and skin, respectively. FPH from the head presents the highest antioxidant and ACE inhibitory activity as well as foam/emulsion capacity among all the FPHs. The FPHs are all able to inhibit three Gram-positive bacteria and three Gram-negative bacteria to varying degrees and have a water solubility >65%. Altogether, the results\ua0demonstrate great potential for recovery of bioactive/functional peptides from the residue of sulfated polysaccharide extraction process enabling efficient biorefining of aquatic resources

Optimization of the fermentation media, mathematical modeling, and enhancement of paclitaxel production by Alternaria alternata after elicitation with pectin

Alternaria alternata fungus is a potent paclitaxel producer isolated from Corylus avellana. Themajor challenge is the lack of optimized media for endophytic fungi productivity. In the effort tomaximize the production of taxoids by A. alternata, several fermentation conditions, including pH(pH 4.0–7.0), different types and concentrations of carbon (fructose, glucose, sucrose, mannitol,sorbitol, and malt extract), and nitrogen (urea, ammonium nitrate, potassium nitrate, ammoniumphosphate, and ammonium sulfate) were applied step by step. Based on the results, A. alternata in amedium containing sucrose 5% (w/v) and ammonium phosphate 2.5 mM at pH 6.0 showed a rapid andsustainable growth rate, the highest paclitaxel yield (94.8 μg gFW−1 vs 2.8 μg gFW− 1 in controls), andthe maximum content of amino acids. Additionally, the effect of pectin was evaluated on fungus, andmycelia harvested. Pectin significantly enhanced the growth and taxoid yield on day 21 (respectively171% and 116% of their corresponding on day 7). The results were checked out by mathematicalmodeling as well. Accordingly, these findings suggest a low-cost, eco-friendly, and easy-to-produceapproach with excellent biotechnological potential for the industrial manufacture of taxoids.</p

Extraction of sulfated polysaccharide from Skipjack tuna (Katsuwonus pelamis) viscera using alcalase enzyme and rainbow trout (Oncorhynchus mykiss) visceral semi-purified alkaline proteases

Fisheries produce a considerable amount of by-products per ton of processed fish, which ranges from 350 to 600 kg. Currently, most of these by-products are used as fish and shrimp meal or as fertilizer, even though they contain significant amounts of quality proteins (enzymes), polysaccharides, and polyunsaturated fats. The present study deals with the extraction of crude alkaline proteases (AP) from rainbow trout (Oncorhynchus mykiss) viscera. The enzyme precipitated at 30–60% saturation displayed the highest yield, purity, and activity compared to other saturation ranges. The maximum activity of AP was obtained at 60 \ub0C and pH 7. AP, ultrasound-AP, Alcalase, and ultrasound-Alcalase were used to isolate sulfated polysaccharides (SPs) from Skipjack tuna (Katsuwonus pelamis) viscera. The extraction yields showed no significant difference between all extracted SPs (p &gt; 0.05). APU-Viscera-SP, AlU-Viscera-SP, and Al-Viscera-SP contained the most sugar (62.22%), sulfate (15.93%), uronic acid (8.84%), and protein (12.69%), respectively. Also, all SPs showed a mixed composition of monosaccharides, including xylose, mannose, rhamnose, GalA (galacturonic acid) and glucuronic acid (GlcA). AP-Viscera-SP, AlU-Viscera-SP, and AlU-Viscera-SP exhibited the highest antioxidant activity in DPPH, ABTS, and metal chelating tests. The highest inhibitor zone against L. monocytogenes, S. aureus, B. cereus, S. enterica, E. coli, and S. typhimurium were in APU-Viscera-SP, and AlU-Viscera-SP, respectively. Overall, the obtained results demonstrated that fish viscera could be a good source of alkaline protease. Besides, this obtained alkaline protease can also be used to extract sulfated polysaccharides with bioactive and functional properties from fish viscera byproducts

Parallel Extraction of Sulfated polysaccharides and Protein Hydrolysate from Skipjack Tuna Head and Their Bioactive and Functional Properties

A new process for parallel extraction of sulfated polysaccharides (SPs) and fish protein hydrolysate (FPH) from tuna head was developed. The effect of type of enzymes (Alcalase, Protamex, and Pancreatin) on the structural, functional, and bioactivity of both SPs and FPHs was also investigated. Initially, SPs were extracted, then the remaining ethanol from polysaccharide precipitation was used to obtain hydrolyzed proteins. Protamex produced SPs with the highest carbohydrate content (50.17%) while Alcalase prompted the highest content of uronic acid/sulfate. The degree of hydrolysis of the FPHs varied by the used enzyme but their amino acid composition fulfilled human requirements. Both SPs and FPHs had antioxidant activity but their efficiency was governed by the type of enzyme and oxidation mechanism. SPs had good metal chelation while FPHs showed good radical scavenging. Recovered FPHs had substantially higher antibacterial activity than the SPs and showed the highest inhibition against\ua0E. coli in concentration of 1\ua0mg/mL. Altogether, parallel extraction of SPs and FPHs could be a promising biorefinery approach for more efficient utilization of tuna head

Ultrasonic-assisted enzymatic extraction of sulfated polysaccharide from Skipjack tuna by-products

The effect of ultrasound pretreatment on extraction efficiency of sulfate polysaccharides (SPs) using alcalase from different by-products of Skipjack tuna including head, bone and skin was evaluated. Structural, functional, antioxidant and antibacterial properties of the recovered SPs using the ultrasound-enzyme and enzymatic method were also investigated. Ultrasound pretreatment significantly increased the extraction yield of SPs from all the three by-products compared with the conventional enzymatic method. All extracted SPs showed high antioxidant potential in terms of ABTS, DPPH and ferrous chelating activities where the ultrasound treatment enhanced antioxidant activities of the SPs. The SPs exerted strong inhibiting activity against various Gram-positive and Gram-negative bacteria. The ultrasound treatment remarkably increased antibacterial activity of the SPs against L. monocytogenes but its effect on other bacteria was dependent on the source of the SPs. Altogether, the results suggest that ultrasound pretreatment during enzymatic extraction of SPs from tuna by-products can be a promising approach to improve extraction yield but also bioactivity of the extracted polysaccharides

Fish Protein Hydrolysate from Sulfated Polysaccharides Extraction Residue of Tuna Processing By‐Products with Bioactive and Functional Properties

Abstract The ethanol‐induced precipitation after enzymatic hydrolysis commonly used for sulfated polysaccharide extraction from marine resources wastes a large amount of proteins. Here, possible extraction of fish protein hydrolysates (FPH) from the ethanol residue of sulfated polysaccharide precipitation from head, bone, and skin of skipjack tuna is investigated. Antioxidant, antibacterial, angiotensin I‐converting enzyme (ACE) inhibitory activities and functional properties of the recovered FPHs are also evaluated. A degree of hydrolysis of 40.93, 38.13, and 37.23 is achieved for FPH from head, bone, and skin, respectively. FPH from the head presents the highest antioxidant and ACE inhibitory activity as well as foam/emulsion capacity among all the FPHs. The FPHs are all able to inhibit three Gram‐positive bacteria and three Gram‐negative bacteria to varying degrees and have a water solubility >65%. Altogether, the results demonstrate great potential for recovery of bioactive/functional peptides from the residue of sulfated polysaccharide extraction process enabling efficient biorefining of aquatic resources

Extraction, partial purification and characterization of alkaline protease from rainbow trout (Onchorhynchus Mykiss) viscera

In this study, crude alkaline proteases were recovered from rainbow trout (Oncorhynchus mykiss) viscera and partially purified by use of different saturation of ammonium sulfate. The enzyme exhibited highest yield, purity and activity when precipitated at a saturation of 40–60% compared to other ranges of saturation. Molecular weight for extracted protease was between 8-24 kDa. The protease had caseinolytic activity over a wide range of temperatures (30-55 °C) and pH (4-12). Soybean trypsin inhibitor and trypsin-chymotrypsin inhibitor strongly inhibited the enzyme activity but it was stable in the presence of surfactant, oxidizing reagents and organic solvents. The proteases had serine protease activity but no collagenase activity was detected. The current study showed that partially purified protease from the digestive tract of rainbow trout could be applicable in food and detergent industry because of its good activity over a wide temperature and pH range and its good thermal stability

Water-soluble polysaccharides from Ulva intestinalis: Molecular properties, structural elucidation and immunomodulatory activities

Water-soluble sulfated polysaccharides extracted from Ulva intestinalis and fractionated using DEAE Sepharose fast flow column to identify their molecular properties and macrophage cells stimulating activities. Crude and fractions (F1 and F2) were formed of neutral sugars (58.7–74.7%), sulfates (6.2–24.5%), uronic acids (4.9–5.9%) and proteins (3.2–10.4%). Different levels of sugar constituents including rhamnose (30.1–39.1%), glucose (39.0–48.4%), galactose (0.0–15.8%), xylose (8.5–11.3) and arabinose (0.0–5.1%). The molecular weight (Mw) of crude and fractionated polysaccharides ranged from 87.1 × 103 to 194.1 × 103 (g/mol). Crude polysaccharides were not toxic to RAW264.7 cells and fractions induced cell proliferation. Fraction F1 stimulated RAW264.7 cells to release considerable amounts of nitric oxide, IL-1β, TNF-α, IL-6, IL-10 and IL-12 cytokines. The main backbone of the most immunostimulating polysaccharide (F1) was consisted of mixed linkages of (1 → 2)-linked rhamnose and (1 → 2)-linked glucose residues. Keywords: Ulva intestinalis, Sulfated polysaccharides, Ulvan, Molecular weight, Immunostimulating activit