Effect of operating parameters on performance of ultrafiltration (UF) to fractionate Catfish protein hydrolysate

The effect of pH, ionic strength and feed concentration on performance of ultrafiltration (UF) to fractionate Catfish protein hydrolysate (CFPH) through 5kDa regenerated cellulose (RC) membrane was studied. The highest and lowest permeate flux belonged respectively to pH 9 and isoelectric point (IEP) with flux reduction of 5.75 L/m2.h at pH 9 and 10.98 L/m2.h at pH isoelectric through operating time. Further, by adding the salt, the highest permeate flux and transmission obtained at highest ionic strength of 0.15 M NaCl with 52.96% of transmission (in average). Then, the transmission reached to 54.18% by increasing feed concentration up to 1.5 mg/ml

Optimization of enzymatic hydrolysis of tilapia (Oreochromis niloticus) by-product using response surface methodology

Fish protein hydrolysate was recovered from tilapia by-product (TB) through enzymatic hydrolysis using alcalase enzyme. Hydrolysis reaction of TB was monitored according to the degree of hydrolysis (DH) by employing O-phtaldialdehyde (OPA) method. Optimization process for obtaining high yield of TB protein hydrolysate was performed using response surface methodology (RSM) by optimizing a combination of four independent variables namely, pH (6.5-8.5), temperature (55-70°C), substrate concentration (10-17.5% w/v), and enzyme concentration (1.5-3.5% w/w) with (DH) as a response. The optimum enzymatic hydrolysis conditions were obtained at pH 7.5, temperature of 60°C, substrate concentration of 15% (w/v) and 2.5% (w/w) of enzyme concentration and yielded about 20.20% of DH after hydrolyzing for 120 min. RSM generated model predicted that 20.42% of DH could be achieved at these conditions and this model was valid based on the DH value obtained from the experimental study (20.31%) which was quite similar with the predicted value. High yield of DH obtained from the optimization process could produce fish protein hydrolysate with good nutritional and functional properties

A Comparative Study between Tilapia (Oreochromis niloticus) By-product and Tilapia Protein Hydrolysate on Angiotensin I-converting Enzyme (ACE) Inhibition Activities and Functional Properties

Tilapia is a popular freshwater fish and among the important cultured fish grown worldwide. In this study, fish protein hydrolysate was produced from tilapia (Oreochromis niloticus) by-product (TB) and tilapia muscle (TM) through enzymatic hydrolysis using alcalase. The TB and TM protein hydrolysates were evaluated for its characteristics in terms of angiotensin I-converting enzyme (ACE) inhibition activity, peptide size distribution, and functional properties. Hydrolysis for 1 h for TB and TM successfully produced low molecular weight peptides (80% at pH2-9) and good emulsifying, water and oil holding capacities. The study indicated that tilapia protein hydrolysates have the potential to be used as functional food products

The effect of operating parameters on ultrafiltration and reverse osmosis of palm oil mill effluent for reclamation and reuse of water.

An attempt was made to reclaim and recover palm oil mill effluent (POME) for water reuse using tubular ultrafiltration (UF) and reverse osmosis (RO) membranes. The reclaimed water was compared with the final discharged water of the local mill. The raw POME was first subjected to a physical pre-treatment process to remove the content of organic matter and suspended solids. The pre-treatment process was coupled with membrane technology (UF and RO) to reclaim the clean water from POME. From the combined techniques of UF (5 bar) and RO (30 bar) the results showed that the turbidity and BOD5 were reduced by 99% and 98.9%, respectively. Compared to the final discharged POME, this suggested method gives a significant difference in BOD5 and turbidity. The final permeate of RO was found to comply with the standards for water reuse. Therefore, the combined UF and RO method is a viable alternative and has a great potential for use in the palm oil industry

Performances of sandwich membrane in reclamation of water from final discharged POME

An investigation was made to examine the performance of sandwich configurations of paired ultrafiltration membranes in reclamation of water from final discharged POME. Two membranes were sandwiched together in different configurations without spacer. Two types of membrane were used in this study which were PES and RC with MWCO 5kDa. The sandwich configurations were known as SS-Sandwich, SB-sandwich, where S indicates that the skin layer faces the feed and B indicates that support layer faces towards the feed. The result of single membrane was compared with both sandwich arrangement. SS-sandwich configuration showed the best permeate quality for PES MWCO 5kDa. The pollutant reduced range up to 80%-90% compared to single membrane which were 60%-70% range. The quality of permeate obtained for total dissolved solid (TDS), suspended solid (mg/L), turbidity, BOD5, COD, were 535 mg/L, <25 mg/L, 0.88 NTU, BOD5 23.3 mg/L, and 48 mg/L. The quality of permeate from SS-sandwich membrane of 5 kDa was beyond reuse standard and approaching drinking water standard for TSS, TDS and turbidity. Therefore it can be concluded that, water reclaimed from treating final discharged from palm oil mill effluent using ultrafiltration technique with right sandwich configuration at optimum operating conditions was successfully complied with WHO reuse water standard

Effect of high-pressure steam treatment on enzymatic saccharification of oil palm empty fruit bunches.

The effectiveness of high-pressure steam treatment (HPST) with various treatment temperatures (170, 190, 210, and 230 °C) on the enzymatic hydrolysis yield of oil palm empty fruit bunches (OPEFB) was successfully investigated. Analysis of the compositions of raw and treated OPEFB showed that significant changes occurred after the HPST was performed. Scanning electron microscopy (SEM) analysis showed that the treated OPEFB gave better results in removing the silica bodies as compared to the untreated OPEFB. This analysis was in agreement with FTIR results, which revealed a significant decrease in the content of hemicelluloses after HPST. During saccharification, the amount of sugar produced was higher for treated OPEFB than untreated OPEFB. Thus, the results suggest that HPST can be applied as an alternative treatment method for the alteration of OPEFB structure and to enhance of the digestibility of the biomass, therefore improving enzymatic hydrolysis

Fractionation of tilapia by-product protein hydrolysate using multilayer configuration of ultrafiltration membrane

Production of small-sized peptides is significant because of their health benefits. Ultrafiltration (UF) membrane provides an effective fractionation of small-sized peptides on a large scale. Thus, the present study was aimed to evaluate the performance of multilayer UF membrane in fractionating tilapia fish by-product (TB) protein hydrolysate by observing the permeate flux, peptide transmission, and peptide distribution under different stirring speed, pH of feed solution, and salt concentration (NaCl). The fractionation process was carried out using a dead-end UF membrane system that consists of a stack of two membrane sheets with different (10/5 kDa) and similar (5/5 kDa) pore sizes in one device. The highest permeate flux (10/5 kDa–39.5 to 47.3 L/m2.h; 5/5 kDa– 15.8 to 20.3 L/m2.h) and peptide transmission (10/5 kDa–51.8 to 61.0%; 5/5 kDa–18.3 to 23.3%) for both multilayer membrane configurations were obtained at 3.0 bar, 600 rpm, pH 8, and without the addition of salt. It was also found that the permeates were enriched with small-size peptides (<500 Da) with a concentration of 0.58 g/L (10/5 kDa) and 0.65 g/L (5/5 kDa) as compared to large-sized peptides (500–1500 Da) with concentration of 0.56 g/L (10/5 kDa) and 0.36 g/L (5/5 kDa). This might indicate the enrichment of small-size peptides through the multilayer membrane which could potentially enhance the biological activity of the protein hydrolysate fraction

Evaluation on performance of dead-end ultrafiltration membrane in fractionating tilapia by-product protein hydrolysate

Conversion of tilapia by-products through enzymatic hydrolysis is a promising alternative to produce a fish protein hydrolysate (FPH). Tilapia by-product (TB) protein hydrolysate consists of peptide mixtures in various sizes. Recovery of small-sized peptides is increasingly becoming a priority due to their special characteristics, which can provide an excellent physiological functions. Ultrafiltration (UF) membrane is an effective and suitable tool for fractionating small size peptides in a large scale. The objective of this study was to evaluate the membrane performance based on the permeate flux and peptide transmission. The fractionation of TB protein hydrolysate was performed through a dead-end UF membrane (10 and 5 kDa) with the effect of stirring speed (0–600 rpm), pH (3, 5, 7, 8 and 9) and salt concentration (NaCl; 0 M, 0.2 M, 0.4 M, and 0.6 M) at varies pressure (1.0, 1.5, 2.0, 2.5 and 3.0 bar). It was found that the transmembrane pressure of 2.5 bar, stirring speed of 600 rpm, pH 8 and without addition of NaCl turned out to be the best parameters which gave permeate flux of 53 L/m2h (10 kDa) and 27 L/m2h (5 kDa), while for the peptide transmission, the value of 87.33% (10 kDa) and 36.11% (5kDa) was obtained. This study indicates that by adding salt, it has lowered the permeate flux and peptide transmission. Finally, through a well-controlled of operating and physicochemical parameters, it was possible to produce peptides with sizes lower than 1000 Da

Assessment on multilayer ultrafiltration membrane for fractionation of tilapia by-product protein hydrolysate with angiotensin I-converting enzyme (ACE) inhibitory activity

Ultrafiltration membrane is a convenient system to fractionate fish protein hydrolysate and recovery of peptide fraction with high ACE inhibitory activity. However, the limitation of applying membrane system in protein fractionation is its poor selectivity. This study aiming to assess the application of multilayer ultrafiltration in order to improve the selectivity of the tilapia by-product protein hydrolysate (TBH) separation by achieving higher amount of small peptides. Flat sheet regenerated cellulose (RC) membrane with molecular weight cut-off (MWCO) of 10 and 5 kDa were used for the separation of peptide mixtures. The membrane were arranged in the orientation of 10/5 kDa and 5/5 kDa, in which these two membrane were stacked together in one device. The performance of multilayer membrane were evaluated based on the permeate flux and peptide transmission, and compare with the single membrane system (5 and 10 kDa). The performance ultrafiltration membrane for fractionating TBH was studied under two different conditions (rotation speed and pH). The highest permeate flux and peptide transmission were obtained at membrane with pore size of 10 kDa (single), followed by 10/5 (multilayer), 5 (single) and 5/5 kDa (multilayer). Based on selectivity analysis, most permeate produced were composed of peptides lower than 1500 Da. When the smaller membrane’s pore size is used (5 kDa membrane and 5/5 multilayer membranes), the amount of small-sized peptide (<500 Da) increased, indicating that selectivity (specifically on small-sized peptide) can be improved. The permeate from multilayer 5/5 and 10/5 kDa membranes have higher value of ACE inhibitory activity (84.04% and 75.59%, respectively) compared with the single membrane (5 kDa – 71.83% and 10 kDa – 64.32%). This might be due to the permeate enriched with small-sized peptide. Thus, application of multilayer membrane shows the potential to recover high ACE inhibitory activity from TBH

Assessment on flux reduction and protein rejection behavior in fractionating tilapia by-product protein hydrolysate by ultrafiltration membrane

Modification of tilapia by-products (TB) into fish protein hydrolysate (FPH) using enzymatic treatment is a favorable approach for enhancing their values and applications in the food industry. The TB protein hydrolysate has a wide range of sizes, which is possible to be fractionated using ultrafiltration (UF) membrane for obtaining small sized peptides. Thus, the present study aims to assess the flux reduction behavior of ultrafiltration membrane by varying transmembrane pressure, stirring speed and solution pH. Regenerated cellulose membrane of 10 kDa molecular weight cut-off (MWCO) was used throughout of the study. It was found that the trends for flux behavior of all parameters were reaching steady state within 60 - 70 minutes. At completion of filtration (at 70 minutes), the highest permeate flux for each operating and physicochemical parameters were at 3 bar (13.6 L/m2h), 600 rpm (42.8 L/m2h) and pH 8 (53.4 L/m2h). In term of protein rejections, significant effects were attained for stirring speeds with reduction of 57% from 0 to 600 rpm and lowest protein rejection (9.6%) was obtained at pH 8. Thus, controlling the operating parameters of the UF process could reduce membrane fouling