Abdul Salam Babji

Effects of Enzymatic Hydrolysis on the Antioxidative and Antihypertensive Activities from Red Tilapia Fish Protein

In this research, activities of antioxidative and antihypertensive peptides, derived from Red Tilapia meat protein (Oreochromis niloticus) by alcalase and thermolysin enzymes were evaluated. The hydrolysis process was performed from 0 - 4 hours at 37°C, pH 7.4. Two hours of hydrolysis with thermolysin and alcalase resulted in degree of hydrolysis of 76.29% and 63.49%, respectively. Hydrolysates obtained after 1 hour and 2 hours hydrolysis were chosen for further study on the bioactive activities. Results showed that thermolysin enzyme yielded higher antioxidant activities than alcalase enzyme based on ABTS and reducing power assays, before and after ultrafiltration for concentrated cut-off interval of hydrolysates. For antihypertensive assay, thermolysin enzyme yielded higher inhibition of ACE enzyme activities after 1 hour hydrolysis while alcalase enzyme yielded higher inhibition activities after 2 hours hydrolysis. Chosen cut-off interval of hydrolysates showed that, thermolysin hydrolysates have a strong inhibition effects towards ACE enzyme than alcalase hydrolysates. Based on SDS-PAGE test, the hydrolysates obtained by alcalase appeared as a smear and have concentrated the most with molecular weight within range ≤14 kDa. Hydrolysates obtained by thermolysin appeared as a band and have concentrated the most with molecular weight of 14 kDa and 3 kDa. Hydrolysates from Red Tilapia may contribute as a health promoting ingredient, to improve shelf-life of functional food and as an ingredient which have the antihypertensive effects towards mild hypertension patients, in functional foods.

Effect of Molecular Weight Reduction of Polypeptides on Angiotensin Converting Enzyme (ACE) Inhibitory Activity in Chicken Skin Hydrolysate (Collagen)

Inhibition of Angiotensin Converting Enzyme (ACE) reduces blood pressure and gives an anti-hypertensive effect. Chicken skin is an undesirable by-product of the poultry industry, disliked by consumer because of the high fat content. The aim of this research is to determine the effect of molecular weight reduction on ACE inhibition activity in chicken skin hydrolysate. Chicken skin is prepared by manually defatting, soaked in acetone and in 0.1M phosphate buffer. Sample hydrolysis is carried out using alcalase enzyme for a duration of 4 hours at 60EsC and pH 9.5. The best degree of hydrolysis (DH), at 4th hour, with value of 49.54 ± 0.79 %, is ultrafiltrated and used in ACE inhibition activity detection. The sample weight ≥ 10 kDa , 3 – 10 kDa and ≤ 3 kDa contains 5.63 ± 0.01 g/L, 2.84 ± 0.06 g/L and 1.07 ± 0.18 g/L peptide content respectively whereas soluble protein content is 0.51 mg/mL for sample weight ≥ 10 kDa, 0.27 mg/mL for sample weight 3 – 10 kDa and 0.23 mg/mL for sample weight ≤ 3 kDa. The ACE inhibition activity in sample weight ≤ 3 kDa is highest with value of 80.38 ± 2.69% followed by sample weight 3 – 10 kDa with a value of 49.40 ± 2.63% and sample weight ≥ 10 kDa with value of 42.73 ± 5.08%. Significant differences ( P ≤ 0.05) exist between sample weight ≤3 kDa and > 3 kDa. This research shows that molecular weight reduction increases ACE inhibition activity.

Porcine DNA Detection in Finished Meat Products Using Different Mitochondrial DNA (mt-DNA) on Polymerase Chain reaction

This study was conducted to detect the presence of porcine DNA in meat products in the market using different mitochondrial (mt) DNA on conventional polymerase chain reaction (PCR). Porcine DNA detection in meat products was tested due to some issues associated with the adulteration of food products in Malaysia. This is an important issue especially for Halal authentication which is required for some religious practices such as in Islam and Hinduism. Many techniques have been developed for determining the Halal status of food products. In this paper, Polymerase Chain Reaction method was used to detect the presence of porcine DNA in meat products. Positive and negative controls were always present for each batch of extraction. DNA of raw pork meat was used as a positive control while nucleus free water is used as negative control. DNA of meat products was amplified by using species-specific primer namely mtATP6 with band size of 83-bp and Pork1 and Pork2 with band size of 531-base pair (bp) mitochondrial (mt) DNA D-loop primer to detect pork species. The present study demonstrated that none of the samples were contaminated with porcine residuals but selected samples with pork meat were positive. The species-specific PCR amplification yielded excellent results for identification of pork derivatives in food products and it is a potentially reliable and suitable technique in routine food analysis for Halal certification

Comparison between Mt-DNA D-Loop and Cyt B primers for porcine DNA detection in meat products

This study was conducted to detect the presence of porcine DNA in meat products in the market using conventional polymerase chain reaction (PCR) and commercial PCR-southern hybridization analysis. Porcine DNA detection in meat products was tested due to some issues associated with the adulteration of food products in Malaysia. This is an important issue especially for Halal authentication which is required for some religious practices such as in Islam and Hinduisms. Many techniques have been developed for determining the Halal status of food products. In this paper, mt-DNA D-loop primer and cytochrome (cyt) b were used to detect the presence of porcine DNA in meat products. Positive and negative controls were always present for each batch of extraction. DNA of raw pork meat was used as a positive control while nucleus free water is used as negative control. A pair of oligonucleotide primer was used namely Pork1 and Pork2 which produced amplicon of 531 base pair (bp) in size. While, PCR-southern hybridizat...

Antioxidant activities of red tilapia (Oreochromis niloticus) protein hydrolysates as influenced by thermolysin and alcalase

The hydrolysis process was performed on fish meat from Red Tilapia (Oreochromis niloticus) by enzymes thermolysin and alcalase under optimum conditions. The hydrolysis was performed from 0 – 4 hours at 37°C. Hydrolysates after 2 hours incubation with thermolysin and alcalase had degree of hydrolysis of 76.29 % and 63.49 %, respectively. The freeze dried protein hydrolysate was tested for peptide content and characterized with respect to amino acid composition. The result of increased peptide content in Red Tilapia (O. Niloticus) hydrolysates obtained was directly proportional to the increase activities of different proteolytic enzymes. The result of amino acid composition showed that the sample used contained abundant Gly, Ala, Asp, Glu, Lys and Leu in residues or peptide sequences. Both enzymatic hydrolysates were tested for anti-oxidant activity with DPPH and ABTS assay. Alcalase yielded higher anti-oxidative activity than Thermolysin hydrolysates after 1 hour incubation, but both enzymes hydrolysates showed a significant decrease of anti-oxidant activity after 2 hours of incubation. Hydrolysates from Red Tilapia may contribute as a health promoting ingredient in functional foods to reduce oxidation stress caused by accumulated free radicals.

Extraction and characterization of elastin from poultry skin

Poultry by-products have a great economic potential that need to be exploited. Poultry skin could be utilized to produce elastin, which is often incorporated in the production of functional food or medicine due to its antioxidative properties. This study was conducted to determine the physicochemical and microstructural characteristics of elastins isolated from broiler and spent hen skin. Analyses including proximate and amino acid composition along with transmission electron microscopy (TEM) were carried out. In this study, elastin was successfully extracted from broiler and spent hen skin using three successive solvents extract of NaCl, acetone and NaOH respectively. It was apparent that the fat content of extracted elastin from broiler skin was higher (P < 0.05) than spent hen’s, with both samples recording less than 1% fat. Moreover, broiler skin elastin also had a higher protein content (68.3%) than spent hen’s (67.8%). Both skin sources contained glycine as the major amino acid (19–20%), followed by glutamic acid, proline, alanine and arginine. The results of TEM indicated that the use of collagenase enzyme or further purification efforts should be incorporated along with the extraction methods used because of the presence of collagen and other debris in the resultant elastin.Poultry by-products have a great economic potential that need to be exploited. Poultry skin could be utilized to produce elastin, which is often incorporated in the production of functional food or medicine due to its antioxidative properties. This study was conducted to determine the physicochemical and microstructural characteristics of elastins isolated from broiler and spent hen skin. Analyses including proximate and amino acid composition along with transmission electron microscopy (TEM) were carried out. In this study, elastin was successfully extracted from broiler and spent hen skin using three successive solvents extract of NaCl, acetone and NaOH respectively. It was apparent that the fat content of extracted elastin from broiler skin was higher (P < 0.05) than spent hen’s, with both samples recording less than 1% fat. Moreover, broiler skin elastin also had a higher protein content (68.3%) than spent hen’s (67.8%). Both skin sources contained glycine as the major amino acid (19–20%), followed by...

Antioxidative and Antihypertensive Activities of Selected Malaysian ulam (salad), Vegetables and Herbs

This study was conducted to investigate antioxidative and antihypertensive activities of selected Malaysian ulam (salad) , vegetables and herbs. The aqueous extract of selected ulam (salad) , vegetables and herbs were analysed for total phenolic content (TPC), antioxidant activities (2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radical cation scavenging assay and ferric reducing antioxidant power assay (FRAP) and antihypertension activity (angiotensin converting enzyme (ACE) inhibitory activity assay). TPC analysis showed that Polygonum minus contains significantly (p<0.05) highest phenolic compound at 48.23 ± 0.17 mg GAE/g as compared to other plants. DPPH analysis showed that P. minus had significantly (p<0.05) highest percentage of radical scavenging activity at 79.09 ± 0.10% as compared to other plants. ABTS analysis showed that Sauropus androgynus had significantly (p<0.05) highest percentage of radical cation scavenging activity at 95.10 ± 0.26% as compared to other plants. FRAP analysis showed that P. minus had significantly (p<0.05) highest ferric reducing power at 63.61 ± 0.73 mmol Fe 2+ /g as compared to other samples. Murraya koenigii had the highest percentage of ACE inhibitory activity (91.20 ± 4.15%). Correlation analysis showed positive and significant (p<0.01) correlation between TPC and FRAP (r = 0.956), TPC and ABTS (r = 0.635), TPC and DPPH (r = 0.630) and TPC and ACE inhibitors (r = 0.645). This shows that Malaysian tropical plants especially P. minus are potential source of natural antioxidant and antihypertensive agents.

Antihypertensive potential of bioactive hydrolysate from edible bird's nest

The aim of this study is to determine and compare the proximate composition, the degree of hydrolysis (DH) and the antihypertensive activity of edible bird’s nest (EBN) hydrolysates of two different drying methods. Four types of enzymes (alcalase, bromelain, pancreatin and papain) were used in this study and with different hydrolysis time (30, 60, 90, 120, 180 and 240 min). The highest DH for alcalase (79.48 – 84.09%), pancreatine (77.10 – 80.45%) and papain (82.33%) for EBN hydrolysates was produced with alcalase treatment at 60 – 90 min, pancreatine treatment at 30 – 90 min and papain treatment at 90 min. Bromelain generated hydrolysates showed low DH. EBN hydrolysed using alcalase, pancreatin and papain have significantly higher protein content compared to raw EBN and the moisture content of all hydrolysates treatments was significantly lower compared to raw EBN. For antihypertensive assay, freeze dried EBN hydrolysates have higher antihypertensive activity compared to spray dried hydrolysates. The highest antihypertensive activity for freeze dried samples was produced by alcalase, bromelain and pancreatin and in the range of 80.22 – 86.97%. Meanwhile, papain proved to be less effective in producing hydrolysate with antihypertensive ability. In conclusion, EBN hydrolysate prepared by alcalase, bromelain and pancreatin could be classified as a functional food as it showed significant antihypertensive activity.

Effects of spray drying and size reduction of edible bird’s nest on in-vitro digestibility

The purpose of this study is to determine the effects of spray drying and size reduction of edible bird’s nest (EBN) on in-vitro digestibility respectively. Sample prepared were EBN microparticulates; 710 µm (EBN710), 300 µm (EBN300) and 38 µm (EBN38), EBN spray died (EBNSD) and raw EBN (EBNraw) as control. Protein content and solubility were determined before the samples being subjected to in-vitro digestibility. Protein content of EBN710 (55.37±0.269%), EBN300 (56.57±0.163%) EBN38 (56.77±0.021%) and EBNraw (55.46±0.269%) was not significantly different (p>0.05) but EBNSD (60.33b+0.346%) was the highest (p<0.05). Solubility results showed that EBNSD had the highest solubility (94.38±1.24%) in water significantly (p<0.05) compared to EBNraw (16.01±0.231%), EBN710 (21.89+0.41%), EBN300 (22.52+0.072%) and EBN38 (27.51±0.321%). Digestibility of EBN300 (88.43±0.95%) was higher (p<0.05) compared to EBNSD (85.23±0.27%). However, treatment of microparticulates and spray drying were not significantly different wi...

Production of enzymatic protein hydrolysates from freshwater catfish (Clarias batrachus)

Fish protein hydrolysate (FPH) was prepared from freshwater catfish (Clarias batrachus) by using Alcalase® 2.4L and Papain. The effect of hydrolysis time (30, 60, 120, 180 min) with enzyme concentration of 1% (v/w substrate); pH = 8.0, 7.0 was studied to determine the degree of hydrolysis (DH), peptide content, proximate composition and amino acid profile. Results showed that the highest DH of Alcalase and Papain FPH were 58.79% and 53.48% after 180 min at 55°C incubation respectively. The peptide content of both FPH increased as hydrolysis time increases. FPH showed higher crude protein content and lower fat, moisture and ash content compared to raw catfish. The major amino acids of both hydrolysates were Glu, Lys and Asp. Content of essential amino acids of Alcalase and Papain hydrolysates were 44.05% and 43.31% respectively.