جستجوی مقالات مرتبط با کلیدواژه "هیدرولیز" در نشریات گروه "صنایع غذایی"

Leishmaniasis is one of the intracellular parasitic diseases that is known as the most common infectious disease after AIDS, tuberculosis and malaria. Leishmaniasis is among the 6 most prevalent endemic diseases and is in fact a tropical and subtropical disease caused by intracellular parasites worldwide. In recent years, treatment of leishmaniasis has been associated with risks due to drug resistance and problems related to the side effects of conventional drugs. The disease is found on all continents except Oceania and is endemic to enclosed areas in North Africa, southern Europe, the Middle East, southeastern Mexico, and Central and South America. The aim of this study was to investigate the cytotoxic effect of bioactive peptides obtained from hydrolysis of tiger squid muscle on promastigotes of Leishmania major.

The variables of enzyme type, ratio of enzyme concentration to substrate, time of hydrolysis and drying method were studied on the characteristics of hydrolysis protein. After determining the percentage of white muscle protein of squid caught from Bushehr port, alkalase and papain enzymes were used at 5% levels for 180 minutes for hydrolysis. Production percentage, protein peptide powder, total antioxidant capacity (TAC), radical scavenging activity of DPPH, nitric oxide (NO) and total thiol groups were measured. Also, the cytotoxicity of Leishmania major promastigotes was evaluated using MTT method. Glucantime was used as a positive control and the untreated group was used as a negative control.

Muscle hydrolysis with 5% Alkalase enzyme caused the highest degree of hydrolysis (63%) and in general, the concentration of 5% of enzymes had a higher degree of hydrolysis than the concentration of 2.5%. Analysis of variance showed that the effect of enzyme, drying time and drying method on all measured variables had a statistically significant difference at the level of one percent (p <0.01). The effect of concentration on peptide dry powder, peptide protein, TAC and thiol was significant. However, no statistically significant difference was observed between enzyme concentrations in DPPH and Nitric Oxide. The dual interaction of enzyme × concentration on the variables of dry powder of peptide and Thiol at the level of 1% showed a statistically significant difference (p <0.01). However, the interaction of enzyme × concentration on other variables was not significant. The results showed that the dual interaction of enzyme × time on all studied variables showed a statistically significant difference. (p <0.01). The dual interaction effect of enzyme × drying method was significant only on Nitric Oxide and Thiol variables (p <0.01). Also, statistical results using analysis of variance showed that the dual interaction effect of concentration × time on the variables of dry peptide powder, peptide powder protein and Thiol had a statistically significant difference. (p <0.01). The dual interaction effect of concentration × drying method on the variables of peptide dry powder, peptide powder protein, DPPH and Thiol was also significant (p <0.01). Statistical results showed that the dual interaction of drying time × drying method on all studied variables except TAC showed a statistically significant difference (p <0.01). The results of analysis of variance for the triple interactions of enzyme × concentration × time and enzyme × concentration × drying method showed statistically significant difference only on Thiol at the level of one percent (p <0.01). The triple interaction effect of enzyme × time × drying method on protein peptide powder, DPPH, Nitric Oxide and Thiol showed a statistically significant difference at the level of one percent (p <0.01). The results of analysis of variance showed a statistically significant difference (p <0.01) with the triple interaction of concentration × time × drying method on the protein content of peptide powder, DPPH, TAC, Nitric Oxide and Thiol at the level of one percent. Finally, the results of analysis of variance showed that quadruple interaction effect of enzyme concentration × time × drying method on all studied variables had a statistically significant difference at the level of one percent (p <0.01). The results of comparing the mean of the quadruple interaction effect of enzyme × concentration × time× drying method showed that the highest amount of peptide powder, the lowest protein content and the best antioxidant activity are obtained in TAC, DPPH, Nitric Oxide and Thiol using digestion method with the help of 5% Alkalase enzyme for 180 minutes using spray dryer method. The results showed that the degree of protein hydrolysis in muscle with alkalase enzyme was 5% higher than other enzymes studied. With the help of 5% alkalase enzyme in 180 minutes and using spray drying method, the lowest amount of protein in hydrolyzed powder, the best antioxidant activity were obtained in TAC, DPPH, Nitric Oxide, Thiol and the highest cytotoxicity. The highest amount of muscle hydrolysis powder was obtained in the presence of 5% alkalase enzyme in 180 minutes and cooling drying method.

MTT results showed that with increasing the concentration of peptide powder obtained from enzymatic hydrolysis of white tiger squid muscle, the mortality rate of Leishmania major promastigotes increased in all study groups. The best level of IC50 among the studied groups was observed at a concentration of 10 mg / ml of hydrolyzate from 5% alkalase enzyme by spray dryer compared to the control group. The results of this study showed that the hydrolysis protein of Sepia pharaonis white muscle produced with 5% Alkalase enzyme has cytotoxic effect on Leishmania major promastigotes and this effect has shown a stronger activity in hydrolysis prepared using spray drying method than other methods.

The use of enzymes for hydrolysis of protein sources is one of the common methods in the food processing. A hydrolysed protein is a complex mixture of peptides and amino acids that are obtained from hydrolysis by various enzymes, acids or alkali. These peptides play important biological role in the body. The orange seed is largely available from the orange juice industries wastes, and its defatted flour contains about 26% protein and can be used as a rich and cost-effective source for production of proteins and peptides of plant sources. In the present study, a protein isolate with high purity was extracted from defatted orange seed flour and then the protein was hydrolysed by using Alcalase enzyme in concentrations of 1, 1.5 and 3% and the hydrolysis time of 2-5 hours at temperature of 45-55 ° C at suitable pH for enzyme activity. Then the optimal conditions for the production of hydrolysed proteins with the highest antioxidant properties (DPPH radical scavenging activity, radical OH scavenging activity, ferric reducing activity and total antioxidant) were determined. Optimum treatment at determined conditions (temperature 54.8 °C, time 3.35 hr and ration of the enzyme to the substrate 1.7 % v/w) with antioxidant properties (DPPH radical scavenging activity (45.85%), radical OH scavenging activity (91.82%), ferric reducing activity (89.35%) and total antioxidant (39.68%) was obtained and antioxidant tests were performed on the optimal treatment for confirmation of the proposed values by software. The results showed that the hydrolysed protein derived from orange seed could be used in the foods formulation as a natural additive and also it can be used as a nutraceutical with high antioxidant ability.

In this study, sodium caseinate was hydrolyzed with Withania coagulans extract and the response surface methodology (RSM) was applied to optimize the effects of hydrolysis conditions including hydrolysis temperature, enzyme concentration and hydrolysis time on the degree of hydrolysis, solubility, and foaming properties. The analysis of variance in RSM showed that the linear effects of enzyme level and hydrolysis time and quadratic effects of hydrolysis temperature were important factors affecting the hydrolysis process remarkably (P<0.0001). Results were indicative of the fact that the increase in responses was obtained by an increase in hydrolysis time and enzyme level. The generated quadratic model showed that the optimum conditions for maximizing the responses were when enzyme concentration of 1.75 (%w/w), temperature of 55.43°C and hydrolysis time of 490 min.

Bee pollen, results from the agglutination of flower pollens with nectar and salivary substances of the honeybees. Honey bees save the pollen in the pollen bag at the third clause of their legs. At the entrance to the hive, pollen is trapped in pollen trap and beekeeper collects it. One of the functional properties of bee pollen is antioxidant activity due to its proteins and phenolic compounds. In this study, effect of enzymatic hydrolysis of bee pollen’s proteins on its anti-oxidative activity and optimization of hydrolysis conditions was evaluated. In this regard, phenolic compounds, DPPH free radical scavenging activity, ferric ion reducing power and ferrous ion chelating properties of pollen were measured (respectively 4.1 µg/ 100 g, 31.86%, 1.89, 4.9). Bee pollens hydrolyzed by Alcalase at 2 to 5 hours and concentration of 1to 2%. Treatments determined by RSM. Anti-oxidative factors of hydrolyzed pollen were evaluated. Results showed that maximum amount of reducing power of hydrolyzed pollen received at 2 hours by enzyme concentration of 2%. Maximum amount chelating activity was 31.71% received at 1.38 hours of hydrolysis; effect of enzyme concentration on chelating activity was insignificant. Maximum amount of DPPH free radical scavenging activity received at 2-3.5 hours and enzyme concentration of 1-1.5%. Chelating and DPPH free radical scavenging activities of bee pollen increased to respectively 26% and 23.65% after hydrolyzing.

In the present research the possibility of bioactive peptide production with the maximum 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity through the enzymatic hydrolysis of pumpkin (Cucurbita pepo) oil cake protein by alcalase was investigated. The optimization of hydrolysis conditions was carried using the Response Surface Methodology with the Central Composite Design plot. For this purpose enzyme concentration of 1-2%, temperature 45-55 °C and the hydrolysis time of 2-5 hours were used. The results showed that the optimum conditions to achieve the maximum DPPH radical scavenging activity were: hydrolysis temperature 50.1 °C, hydrolysis time 3.53 hour and the enzyme concentration 2% that showed anti-oxidant activity of 89.47% which was to a large extent similar to the suggested amount by the software (88.08%). R2 and adjusted R2 of the suggested model were 0.9585 and 0.9211 respectively. Moreover the lack of fit was calculated 0.2434 that indicated the reliability and fitness of suggested the model based on the considered response. Based on the results, the anti-oxidative peptides can be applied to the development of functional foods.

Proteins are vital substances for health since they provide nitrogen, amino acids and the energy required for normal body performance. However, the applications of proteins are limited due to their certain properties, such as their low solubility. The enzymatic hydrolysis of proteins is an extensively used approach to produce bioactive peptides and promote the chemical, functional and nutritional properties of proteins. These compounds have interesting biological properties such as anti-oxidative, anti-hypertensive, anti-bacterial, anti-cancer and anti-thrombotic activities. Lipid peroxidation is one of the main reasons behind the deterioration of foodstuffs during processing and storage. In this case, the addition of anti-oxidative compounds is considered as an effective way to improve the shelf-life of lipid containing foods. Due to carcinogenic effect of synthetic anti-oxidative compounds, extensive efforts have been done to find natural anti-oxidative compounds with plant origin during recent years. Pumpkin (Cucurbitapepo) seeds are rich of proteins, unsaturated fatty acids, phytosterols and essential minerals like Zn, K, Ca, Mg, Fe, Cu and P. Oil content of pumpkin seeds is about 40-60%, and mostly consisted of oleic, palmitic and stearic acids. On the other hand, its protein content is about 45-46%, and this amount will reach to 55-56% after defatting. To date, pumpkin seeds have been mainly used for pumpkin oil production. After the oil extraction, a protein-rich by-product (pumpkin oil cake) remains, which is often used for animal feeding. In this study, the enzymatic hydrolysis of pumpkin oil cake protein isolate by a food-grade protease named trypsin was attempted and the optimum treatment was selected based on the DPPH radical scavenging and ferrous ion chelating activities
In this study, the optimization of the hydrolysis of pumpkin (Cucurbitapepo) oil cake protein was investigated using response surface methodology (RSM) and central composite design (CCD) in order to achieve the maximum DPPH radicals scavenging and metal ion chelating activities. For this purpose, trypsin concentrations of 1-2% and hydrolysis temperatures and times of 35-45 ċ and 2-5 hours were examinedas independent variables.
Preparations of pumpkin oil cake protein isolate (POCPI)
Defatted pumpkin oil cake was dispersed in distilled water (1:10 w/v). The pH was adjusted to 10 with 1N NaOH, mixed for 1 hour at room temperature and centrifuged at 5000g for 20 minutes (Combi514R, South Korea). The supernatant was collected, pH was adjusted to 5 with 1N HCl and centrifugation was performed at the same condition. Supernatant was discarded and precipitate was collected as pumpkin oil cake protein isolate.
Enzymatic hydrolysis
Pumpkin oil cake protein isolate was dispersed in tris-HCl at pH= 8 for trypsin enzymatic treatment (5% w/v). After that, trypsin was added at 1%, 1.5% and 2% and hydrolysis was carried out for 2, 3.5 and 5h at 200 rpm in shaker incubator (8480-VS, South Korea). Hydrolysis temperatures were 35, 40 and 45˚C. At the end of hydrolysis, the enzyme was inactivated for 15 minutes at 85˚C; dispersion was centrifuged at 4000g for 30 minutes, the supernatant was collected and freeze dried.
DPPH radical scavenging activity
An aliquot of 1000 microliterpumpkin oil cake proteinhydrolysate was mixed with 1000 microliter of 0.1mM DPPH solution prepared in 96% ethanol. The mixture was allowed to stand for 60 minutes in the dark and the absorbance was read at 517 nm. The blank was prepared with the same manner except that 1000 microliter water was used instead of 1000 microliter pumpkin oil cake proteinhydrolysate.
Ferrous ion chelating activity
Pumpkin oil cake protein hydrolysate(4.7 ml) was mixed with 0.1 ml 2mM FeCl2 and 0.2 ml 5 mM ferrozine and was kept at room temperature for 20 min. The absorbance was read at 562 nm and the blank sample was prepared with the same manner except that 4.7 ml distilled water was used instead of sample.
The results of this study, showed that the optimum conditions to reach the maximum DPPH radicals scavenging and metal ion chelating activities were 35 ċ, 5h, 1.1% enzyme concentration and 45 ċ, 2.05h and 2% enzyme concentration that showed DPPH radicals scavenging and metal ion chelating activities of 76.28% and 49.61% respectively. These results were to large extent similar to those suggested by Design Expert software (75.89% and 50.84%). The R2 was 0.9184% and 0.9761% for DPPH radicals scavenging and metal ion chelating activities respectively. Moreover the adjusted R2 was estimated to be 0.1333 and 0.1827 for DPPH radicals scavenging and metal ion chelating activities respectively, which suggested the suitability and fitness of proposed model for the considered responses.
Based on the results, pumpkin oil cake protein hydrolysate demonstrated appropriate anti-oxidative and metal ion chelating abilities. The results of this study indicated that pumpkin oil cake protein hydrolysate had the ability to be used as an effective and natural anti-oxidative compound in lipid containing foods.

The Influence of the main pretreatment variables on fermentable sugar produced from walnut green skin is studied using design of experiments (DOE) based on concentrated acid hydrolysis. Levels of pretreatment temperature (65, 80, 90oC), process time(120, 180, 240 minute), solid content (5, 10, 15%) and concentration of sulfuric acid (20, 0, 60%) were selected according to previous results. Glucose and pentose composition, as well as furfural and acetic acid were analyzed by HPLC and modeled by a quadratic equation. The mathematical model was validated by an independent experiment. Optimization based on mathematical model showed that maximum glucose concentration was 12.724% in 90oC, 36% acid concentration, 15% solid content and 175 min process time.

The effect of enzymatic hydrolysis by Alcalase on degree of hydrolysis (DH), peptide chain length (PCL) and nitrogen recovery (NR) of White cheek shark meat (Carcharhinus dussumieri) has been studied. Hydrolysis carried out in four stages each at 10, 20 and 30 minutes. DH, and NR decreased, but PCL increased in each stage in compare with the previous one. The mean of DH in the whole process of 10, 20 and 30 minute were 1.91, 2.25, 2.53 for DH, 49.43, 56.58, 60.77 for NR, and 52.15, 44.35, 39.44% for PCL, in that order. However, at longer hydrolysis time, DH, and NR increased, but PCL decreased significantly (P<0.05).