Showing 9 results for Ahmadi Gavlighi
B. Fatan, H. Ahmadi Gavlighi, M.a. Sahari,
Volume 8, Issue 2 (Spring 2019)
Abstract
Aims: The purpose of the present study was to hydrolyze Sardinella sindensis protein isolate by pancreatin enzyme and then fractionation hydrolysate based on molecular weight and finally evaluating and comparing the anti-oxidative and anti-diabetic properties of the fractions with hydrolysate.
Materials & Methods: Protein isolate from Sardinella sindensis muscle was extracted and then hydrolyzed using pancreatin enzyme in two enzyme/substrate ratio of 2.5 and 5% (W/W) for 2h. The hydrolysates were fractionated into three fractions included FPH-I (<2kDa), FPH-II (2-10kDa) and FPH-III (>10kDa) using an ultrafiltration (UF) membranes. The antioxidant and anti-diabetic activiteis of the fractions and hydrolysate were investigated.
Findings: The degree of hydrolysis increased with increasing hydrolysis time and it was significant between 30 and 60 minutes (p<0.05). FPH-III showed the highest DPPH radical scavenging activity. In terms of chelating activity on Fe2+, there was no significant difference between the fractions and hydrolysate (p>0.05). Also, FPH-III showed a better ABTS radical-scavenging activity. FPH-III had the highest inhibitory potential against α-amylase at 2.5%. In addition, the inhibitory effect of samples at 20mg/ml against α-glucosidase was less than 50%.
Conclusion: FPH-III from Sardinella sindensis protein isolate by pancreatin enzyme had the highest DPPH radical scavenging, ABTS+ activity and alpha-amylase inhibitory.
Saeed Khajavi, Mehdi Tabarsa, Hassan Ahmadi Gavlighi, Masoud Rezaie,
Volume 10, Issue 1 (1-2021)
Abstract
Polysaccharides possess diverse biological properties due to complexity of chemical structure and heterogeneity of molecular weight which could be improved through engineering approaches and chemical modifications. The objective of the present study was to determine the antioxidant and anti-diabetic effects of marine and land originated polysaccharides and explore the correlation between molecular weight and biological activities. Hence, four polysaccharides with varying size distribution and average molecular weight including fucoidan and alginate from brown seaweed Padina pavonica and polysaccharides from Flixweed (Descurainia sophia) and Fennel (Foeniculum vulgare) were subjected to hydrolysis in three levels using 0.05N hydrochloric acid at 100 C for 5, 10 and 20 minutes. The average molecular weight ranged between 2059.5-3781.8 in fucoidan, 1774.4-2324.9 in alginate, 720.4-1373.8 in Flixweed and 5752.6-14077.5 × 103 g/mol in Fennel. The relation between molecular weight reduction and α-amylase activity inhibition was decreasing in fucoidan (52.1-32.8%) and alginate (67.6-32.2%) and increasing in Fennel (61.2-45.0%). Reduction of molecular weight enhanced the DPPH radical scavenging and ferric reducing power of fucoidan (47.9-27.8%; 0.47-0.37 Abs) and Fennel (39.0-12.7%; 0.34-0.16 Abs). The effect of molecular weight reduction was limited on antioxidant activities of alginate and Flixweed. Overall, the findings of the current study revealed that molecular weight is a determinant factor affecting bioactivities of the tested polysaccharides and thus their applications as ingredients having anti-diabetic and antioxidant functions could be possible in their native and/or hydrolyzed forms.
Volume 12, Issue 2 (Spring 2024)
Abstract
Aims: The purpose of the present study was to investigate the antioxidant and anti-inflammatory properties of glucosamine hydrochloride (G-HCl), glucosamine sulfate sodium chloride (GS-Na) and glucosamine sulfate potassium chloride (GS-K) isolated from the shells of Litopenaeus vannamei obtained from a shrimp processing plant.
Materials &Methods: G-HCl was synthesized via hydrolysis of chitin with concentrated HCl followed by several sequential decolorization, crystallization and washing steps. Using G-HCl as the precursor, addition of sodium and potassium sulfates at 40 ºC for 1 h resulted in production of GS-Na and GS-K.
Findings: The yield of chitin was found 19.9% and those of glucosamine products ranged between 75.5%-82.5%. The HPAEC-PAD indicated the presence of glucosamine monomers, as compared with commercial standard, with different elution time to that of glucose. The appearance of characteristic signals of O-H, N-H and C-O-C in the FT-IR spectra provided further support of glucosamine successful isolation. SEM images and EDX spectra of glucosamines confirmed the elemental compositions of samples and their polyhedral crystalline structures. DSC and TGA thermograms indicated endothermic and exothermic peaks specific to glucosamine products. Relatively low DPPH and ABTS radical scavenging activities and ferric reducing power was obtained for all glucosamine products. all the glucosamine derivatives indicated an anti-inflammatory effect on LPS-simulated RAW264.7 cells.
Conclusion: Glucosamine products showed no cytotoxicity and down-regulated the release of NO in RAW264.7 murine macrophage cells induced by LPS. Overall, the present results indicated the successful production of glucosamine from the waste of L. vannamei processing plant with antioxidant and anti-inflammatory properties.
Volume 16, Issue 87 (5-2019)
Abstract
In this study, the effect of different treatments including method 1- homogenized by-product (BP-FPI), method 2- washing of homogenized by-product by distilled water (WBP-FPI), method 3- washing of homogenized by-product by CaCl2-citric acid (CaCi-BPFPI), method 4- CaCl2-citric acid treated –washing by distilled water (CaCi-W- BPFPI), method 5- washing by distilled water- CaCl2-citric acid treatment (W-CaCi-BPFPI) on composition of protein isolate from rainbow trout (Oncorhynchus mykiss) by-product were investigated. Washing by distilled water (method 2) and distilled water + combination of CaCl2 + citric acid (method 5) had significant effect on heme iron and phospholipid (P < 0.05). Washing methods influenced protein yield and the lowest yield (9.4%) was obtained using method 5 (P < 0.05). Washing-derived proteins were lighter in color compared with that obtained from by-product. Method 1 resulted in higher redness (9.36) while that obtained with method 5 showed the lowest redness (1.19) (P < 0.05). Protein hydrolysate produced from method 5 protein isolate had high antioxidant activity in a dose-dependent manner. Additionally, the presence of small peptides in hydrolysate contributed to its anti-diabetic activities. Results indicated that washing by distilled water (method 2) or combined with CaCl2 + citric acid (method 5) is necessary for production of protein isolate from rainbow trout processing by-product.
Volume 17, Issue 100 (june 2020)
Abstract
To meet the consumer's interests for natural remedies, food and pharmaceutical industries calls for a safe and green methods for food aims extraction. Besides, carrot juice industry, possess high potential for processing the less expensive by-products to extract high-value ingredients named carotenoids. The purpose of the present study was therefore to extract beta-carotene from carrot pomace using green solvent (distilled water containing 2% ethanol and 4% surfactant). Results showed that among the used solvents for one-cycle extraction, 1-propanol and ethanol without significant differences (P> 0.05) were the most efficient with respectively 0.56 and 0.51 mg/g of CP beta-carotene content. Whiles, for four-cycle extraction the ethanol was the most capable (0.92 mg/g of CP). In addition, the poor ability of 2% ethanol containing distilled water (0.04 mg/g of CP) was significantly increased in the expense of enzyme hydrolysis via Endozym ® Pectofruit (61 U as pectinase activity). Moreover, the 4% of all of the surfactants (soy lecithin, span 20, tween 20 and 80) were significantly increased the extraction capability of the green solvent, wherein, the highest beta-carotene content was extracted with tween 80 (0.29 mg/g of CP). As well, all surfactants showed synergistic effect with enzyme pretreatment resulting up to 62% efficiency for tween 80 compared to four-cycle extraction with ethanol. All in all, the composed of distilled water: ethanol: tween 80: span 20 (94:2:2:2) led to a green extraction of beta-carotene from carrot pomace with 0.84 mg/ g of CP beta-carotene content and 90% extraction yield.
Volume 18, Issue 116 (October 2021)
Abstract
Sulfated polysaccharides presenting in the cell wall of seaweeds and aquatic plants exhibit a diverse range of biological functions mainly due to their particular structural and molecular properties. The aim of the current study was to evaluate the inhibition of oxidation reactions and activities of digestive enzymes including α-amylase and α-glucosidase by sulfated polysaccharides from aquatic plant Myriophyllum spicatum. After the removal of pigments and low molecular weight compounds, polysaccharides were extracted by distilled water at 60°C for 2 hours. Polysaccharide purification using DEAE Sepharose FF led to production of two fractions including F1 and F2. Obtained polysaccharides were considerably capable of scavenging DPPH free radicals (20.62-64.81%) and reducing Fe3+ ions (0.24-0.50 Abs) with F1 fraction exhibiting the greatest activity. Polysaccharides inhibitions against α-amylase activity were greatly different (22.50-63.20%) with the lowest IC50 being 1.31 mg/mL for F2 fraction. α-glucosidase activity was reduced to various levels (1.30-89.5%) and the lowest IC50 of 10.0 mg/mL was observed for crude polysaccharide. Overall, these findings indicated that sulfated polysaccharides from M. spicatum L. possess promising antioxidant, α-amylase and α-glucosidase inhibition potentials depending on their chemical and molecular structure and thus could be considered as antioxidant and anti-diabetic agents.
Volume 18, Issue 117 (November 2021)
Abstract
Pomegranate peel is the main by-product during pomegranate processing that valuable source of bioactive compounds with health-beneficial effects. This study has comparatively assessed the effects of two extraction methods (enzymatic and acidic) on pomegranate peel by measuring their bioactivity in terms of total phenolic content (TPC), antioxidant activity, and antidiabetic properties using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) radical cation decolourization assays, and the α-amylase and α-glucosidase inhibition assays. The TPC mg gallic acid equivalents per g dry weight (GAE mg/g dw) of extracted pectin was ~ 243 and ~ 116 for enzymatic and acidic methods, respectively. The DPPH IC50 of enzymatic pectin was significantly lower than that of acidic pectin (p < 0.05). The ABTS IC50 of enzymatic pectin and acidic pectin was ~ 361 and ~ 945, respectively. The enzymatic pectin showed a significantly stronger α-amylase and α-glucosidase inhibition effect as compared to the acidic pectin. The α-amylase inhibition was stronger than α-glucosidase inhibition for all samples.
The results indicated that enzymatic extracted pectin showed antioxidant and antidiabetic potential, which could be considered as a promising candidate for functional foods in food formulation.
Volume 22, Issue 1 (1-2020)
Abstract
This study investigated partial replacement of nitrite by Pomegranate Peel (PPE) and Pistachio Green Hull Extracts (PGHE) in cooked sausages and their effects on oxidative, microbial, and physicochemical properties of the samples. To this end, 250, 500, 750, 1,000, and 1,250 ppm of the two extracts and 100, 80, 60, 40, and 0 ppm of nitrite were added to the sausages and the peroxide and TBARS values, microbial tests, sensory evaluation, and color factors were measured during 30 days storage at 4ºC. Antioxidant and antimicrobial properties of both treatments were as well as the control, or sometimes better than it. PGHE treatments had better color factors compared to PPE treatments. Sensory scores of PPE3 and PGHE3 (containing 60 ppm nitrite and 750 ppm of extracts) were not significantly different compared to the control. Thus, reduction of nitrite up to 50% and replacement of it by PPE or PGHE do not cause great changes in quality parameters of sausage and improve its functional properties.
Volume 23, Issue 1 (1-2021)
Abstract
Application of antioxidants is a common way for retarding oxidation. Due to adverse effects of synthetic antioxidants on health, the use of natural and safe antioxidants is considered essential. Pistachio green hull is a waste product and low-cost source of phenolic compounds. The use of phenolic compounds in food formulations has some limitations. In this study, the encapsulation of Pistachio Green Hull (PGH) phenolic compounds was carried out by spray-dryer using Maltodextrin (MD) as a wall material. For this purpose, the effective factors including the inlet temperature, dilution factor, wall:core ratio, and rate of feeding were optimized. MD, PGH extract powder, and encapsulated phenolic compounds produced under optimum conditions (ME) were characterized by Scanning Electron Microscopy (SEM), FTIR, X-ray Diffractometry (XRD), and Differential Scanning Calorimetry (DSC).Under optimum conditions, the amount of phenolic compounds and the encapsulation efficiency were 32.1 mg GAE g-1 dp and 81%, respectively. DSC results showed that the microencapsulation had improved thermal stability of phenolic compounds. The DPPH test results indicated that the antioxidant activity of the free PGH extract was 10% higher than encapsulated one (ME). Storage stability results indicated that the amount of phenolic compounds of PGH extracts and ME after 60 days storage decreased by more than 29 and 4%, respectively. The microcapsules obtained can be used in the production of functional foods and pharmaceutical products, due to their antioxidant content and presence of phenolic compounds.
