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Characterization of crude 5'-phosphodiesterase from germinated adzuki (Vigna angularis L.) beans

Pui LP, Mohammed AS, Ghazali HM

Acta Sci Pol Technol Aliment, 2020 9 27;19(3):319-331.
PMID: 32978914 DOI: 10.17306/J.AFS.0804

BACKGROUND: 5'-Phosphodiesterase (5'-PDE) is an enzyme that hydrolyzes RNA to form 5'-inosine monophosphate (5'-IMP) and 5'-guanosine monophosphate (5'-GMP). These 5'-nucleotides can function as flavor enhancers. Adzuki beans (Vigna angularis L.) are found to be high in 5'-PDE.
METHODS: 5'-phosphodiesterase (5'-PDE) enzyme was characterized from adzuki beans, in which the optimum pH and temperature were determined. In addition, the stability of 5'-PDE was assessed at different pH and temperature. The effects of cations and EDTA were evaluated to characterize the 5'-PDE enzymes further.
RESULTS: The alkaline 5'-phosphodiesterase has an optimum pH of 8.5. This enzyme is also thermostable, with an optimum temperature of 80°C. The stability in terms of temperature and pH was also determined, and was found to be stable in the pH range of 7.0-8.5. This enzyme was found to retain more than 80% of its activity for 4 days at 60 and 65°C. In addition, the effects of 14 different metal ions, 4 types of detergents and ethylenediaminetetraacetic acid (EDTA) on 5'-PDE were studied. Ca2+, K+, Mg2+ and Li+ activated 5'-PDE while Na+, Zn2+, Ni+, Hg+, Cu2+, Pb2+, Fe2+, Al3+, Ba2+ and Co2+ were inhibitory. EDTA, Triton X-100 and sodium dodecyl sulfate (SDS) were strong inhibitors of 5'-PDE, while Tween 80 and Tween 20 were slightly inhibitory. The effects of cations and EDTA suggest that 5'-PDE from adzuki beans is a metalloenzyme.
CONCLUSIONS: Although 5'-PDE from adzuki beans has a high temperature optimum of 80°C, the enzyme is more stable at 60°C, and different cations affected the activity of the enzyme differently.

Matched MeSH terms: Hydrolysis
Fulltext Explorative Xylitol Detection from Lignocellulosic Biomass Fermentation of Coconut Husk Using HPLC C18 Column

Mariam-Aisha Fatima, Muhammad Fahmi Mehdin, Nurain Nasrudin, Neelam Shahab

Journal of Management & Science, 2018;16(2):29-38.
MyJurnal

Lignocellulosic biomass, found in wooden plant husks is a potent renewable material source which can be utilised to form various chemicals and biomaterials including polyols such as xylitol. Xylitol has been used commercially as an alternative to sucrose in many products as bulk sweetener in non-cariogenic confectionery as well as in diabetic diets and solutions for parenteral nutrition. Therefore, this study aims to optimise separation parameters of the Shimadzu high performance liquid chromatography (HPLC) (Model No: LC-20A) and quantify the potential of coconut husk as substrate for Candida albicans in producing xylitol using HPLC. Pretreatment to depolymerise components of biomass i.e. cellulose, hemicellulose and lignin were done using dilute acid hydrolysis method which yielded fermentable reducing sugars, xylose. Xylose is a monosaccharide with an aldehyde functional group, a reducing sugar which is then utilised and fermented by the yeast Candida albicans to form xylitol. In this study, the media used for fermenting pretreated coconut husk and Candida albicans is a synthetic defined (SD) minimal broth. Growth curves against concentration of reducing sugar were plotted to determine utilisation and production trends with specific mixes of carbon sources. The presence of reducing sugars were tested using 3,5-dinitrosalicylic acid (DNS) assay in pretreated coconut husk yielded 13.22 g/L. In order to analyse the product with HPLC, an existing protocol is modified for Hypersil GOLD™ C18 column with acetonitrile as the mobile phase. Results obtained from HPLC analyses using developed protocol suggested the formation of xylitol from the fermentation of pretreated husk by Candida albicans. These can be followed by purification of fermented media in obtaining a better separation of contaminating peaks.

Matched MeSH terms: Hydrolysis
Morphological, chemical and thermal analysis of cellulose nanocrystals extracted from bamboo fibre

Rasheed M, Jawaid M, Parveez B, Zuriyati A, Khan A

Int J Biol Macromol, 2020 Oct 01;160:183-191.
PMID: 32454108 DOI: 10.1016/j.ijbiomac.2020.05.170

This work investigates the extraction of cellulose nanocrystals (CNC) from bamboo fibre as an alternative approach to utilize the waste bamboo fibre. In this study, bamboo fibre was subjected to acid hydrolysis for efficient isolation of CNC from bamboo fibre. The extracted CNC's were morphologically, characterized via Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM). The energy Dispersive X-rays (EDX) provided the elemental composition of the prepared CNC's and X-ray diffractometer (XRD) exhibited their crystallinity. The physiochemical analysis was done via Fourier Transform Infrared (FTIR); and their thermal analysis was revealed by Thermogravimetric Analysis (TGA) and Differential scanning calorimetry (DSC). As from their morphological investigations, rod like structures of CNC's were observed under SEM analysis with higher carbon content as demonstrated by EDX, while needle shaped CNC's were observed from TEM and AFM studies. Acid hydrolysis for 45 min resulted into higher degree of crystallinity and higher yield of CNC's about 86.96% and 22% respectively. Owing to higher quality of CNC's obtained as a result of efficient and modified techniques, these can find potential usage in nanocomposites for biomedical and food packaging application.

Matched MeSH terms: Hydrolysis
Preparation and characterizations of oil palm fronds cellulose nanocrystal (OPF-CNC) as reinforcing filler in epoxy-Zn rich coating for mild steel corrosion protection

Azani NFSM, Haafiz MKM, Zahari A, Poinsignon S, Brosse N, Hussin MH

Int J Biol Macromol, 2020 Jun 15;153:385-398.
PMID: 32145234 DOI: 10.1016/j.ijbiomac.2020.03.020

Oil palm frond (OPF) is one of largest contributions to the biomass waste from oil palm plantation. In this work, OPF has been successfully utilized to prepare cellulose nanocrystal (OPF-CNC) by acid hydrolysis. OPF was initially treated with autohydrolysis treatment. The obtained OPF-CNC was characterized via complementary analyses. The produced OPF-CNC showed a high crystallinity index value (60%) and high BET surface area (26.10 m2 g-1) as compared to α-cellulose (crystallinity index: 54% and BET surface area:7.14 m2g-1). The surface analyses via scanning electron microscope (SEM) and transmission electron microscopy (TEM) demonstrated that the OPF-CNC has a smooth surface with a needle-like shape, where the average length and diameter are 95.09 nm and 6.81 nm, respectively. The corrosion analyses via electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PD) illustrate that the coated mild steel with the inclusion of 0.5 wt% OPF-CNC has managed to sharply reduce the corrosion (99%). The coated mild steel with the inclusion of 0.5 wt% OPF-CNC showed the highest hydrophobicity (100.5 ± 0.7°) and has lowest amount of O via water contact angle and energy dispersive X-ray spectroscopy (EDX) analyses respectively, indicating lowest corrosion rate.

Matched MeSH terms: Hydrolysis
Antibacterial efficacy of chitosan- and poly(hexamethylene biguanide)-immobilized nanofiber membrane

Ng IS, Ooi CW, Liu BL, Peng CT, Chiu CY, Chang YK

Int J Biol Macromol, 2020 Jul 01;154:844-854.
PMID: 32194127 DOI: 10.1016/j.ijbiomac.2020.03.127

In this study, polyacrylonitrile (PAN) nanofiber membrane was prepared by an electrospinning technique. After alkaline hydrolysis, the ion-exchange nanofiber membrane (P-COOH) was grafted with chitosan molecules to form a chitosan-modified nanofiber membrane (P-COOH-CS). Poly(hexamethylene biguanide) (PHMB) was then covalently immobilized on P-COOH and P-COOH-CS to form P-COOH-PHMB and P-COOH-CS-PHMB, respectively. The nanofiber membranes were subjected to various surface analyses as well as to the evaluations of antibacterial activity against Escherichia coli. The optimal modification conditions for P-COOH-CS-PHMB were attained by water-soluble chitosan at 50 kDa of molecular weight, coupling pH at 7, and 0.05% (w/w) of PHMB. Within 10 min of treatment, the antibacterial rate was close to 100%. Under the similar conditions of antibacterial treatment, the P-COOH-CS-PHMB exhibited a better antibacterial efficacy than the P-COOH-PHMB. When the number of bacterial cells was increased by 2000 folds, both types of nanofiber membranes still maintained the antibacterial rate close to 100%. After five cycles of repeated antibacterial treatment, the antibacterial efficacy of P-COOH-PHMB was 96%, which was higher than that of P-COOH-CS-PHMB (83%). The experimental results revealed that the PHMB-modified nanofiber membranes can be suitably applied in water treatment such as water disinfection and biofouling control.

Matched MeSH terms: Hydrolysis
Fulltext Morphological, Physiochemical and Thermal Properties of Microcrystalline Cellulose (MCC) Extracted from Bamboo Fiber

Rasheed M, Jawaid M, Karim Z, Abdullah LC

Molecules, 2020 Jun 18;25(12).
PMID: 32570929 DOI: 10.3390/molecules25122824

Bamboo fibers are utilized for the production of various structures, building materials, etc. and is of great significance all over the world especially in southeast Asia. In this study, the extraction of microcrystalline cellulose (MCC) was performed using bamboo fibers through acid hydrolysis and subsequently different characterizations were carried out using various advanced techniques. Fourier transform infrared (FTIR) spectroscopy analysis has indicated the removal of lignin from MCC extracted from bamboo pulp. Scanning Electron Microscopy (SEM) revealed rough surface and minor agglomeration of the MCC. Pure MCC, albeit with small quantities of impurities and residues, was obtained, as revealed by Energy Dispersive X-ray (EDX) analysis. X-ray diffraction (XRD) indicates the increase in crystallinity from 62.5% to 82.6%. Furthermore, the isolated MCC has slightly higher crystallinity compared to commercial available MCC (74%). The results of thermal gravimetric analysis (TGA) demonstrate better thermal stability of isolated MCC compared to its starting material (Bamboo fibers). Thus, the isolated MCC might be used as a reinforcing element for the production of green composites and it can also be utilized as a starting material for the production of crystalline nanocellulose in future.

Matched MeSH terms: Hydrolysis
Fulltext Growth kinetics of citrus suhuiensis cell suspension

Noor Illi Mohamad Puad, Muhammad Alif Sarji, Nur Alia M. Fathil, Muhammad Yusuf Abduh

Biological and Natural Resources Engineering Journal, 2018;1(1):1-13.
MyJurnal

Citrus is one of the major commodities in many countries including Malaysia.
However, production of citrus including Citrus suhuiensis (C. suhuiensis) is declining due to
diseases and inability to withstand low temperatures. Plant cultures such as cell suspension have the
potential in propagating disease-free and healthy Citrus fruits with value-added characteristics.
However, studies related to C. suhuiensis is still scarce. Therefore, the growth kinetics of C.
suhuiensis cell suspension culture was studied. Friable callus of C. suhuiensis which was induced
from seeds was inoculated into MS medium with 30 g/L sucrose, 0.5 g/L malt extract and 2.0 mg/L
2, 4-D for the cell suspension initiation. Several batch experiments using a few types of sugars
(sucrose, glucose and fructose) were carried out. The cell dry weight (CDW) of C. suhuiensis was
recorded for 30 days of culture period and residual sugars in the medium were analyzed using
HPLC. Cells grown in 30 g/L sucrose achieved the highest CDW (9.559 g/L) with µmax equals to
0.00512/h, compared to glucose and fructose. In addition, sucrose is the preferred carbon source
with the highest uptake rate (0.213 g/L·h). Cells completely hydrolyzed sucrose into glucose and
fructose after 5 days of inoculation. All sugars were completely utilized by C. suhuiensis cells after
25 days. The kinetic growth parameters determined from batch experiments were then used for
model simulation and verification in MATHCAD 15. After adjustments and refinement to the
selected kinetic parameters, the model has fairly described and predicted the growth and sugars
profile of C. suhuiensis cells. The proposed model can be used to predict sucrose hydrolysis, glucose
and fructose formation from sucrose and their consumption by plant cells and also for larger scale
of growth.

Matched MeSH terms: Hydrolysis
Fulltext Effects of pH on Phosphorus Recovery from Different Composition of Food Waste Using Anaerobic Batch Digestion

Selaman, R., Newati Wid

Borneo Journal of Medical Sciences, 2018;12(101):63-64.
MyJurnal

Anaerobic digestion is a process by which microorganisms break down biodegradable material in the absence of oxygen. The process involves hydrolysis, acidogenesis and methanogenesis stages. Anaerobic digestion of food waste has been widely investigated for biogas recovery but limited study was performed on phosphorus recovery, which is reported depleting. Food waste is produced every day and dumped on landfill for final disposal which may lead to environmental issues such as odour problems and greenhouse gases release, due to decomposing of food waste, hence impacts global climate change. In anaerobic digestion pH is a very crucial parameter in an attempt to recover phosphorus as it highly influences the production of organic acids during acidogenesis.

Matched MeSH terms: Hydrolysis
Characterization of Microcrystalline Cellulose Isolated from Conocarpus Fiber

Fouad H, Kian LK, Jawaid M, Alotaibi MD, Alothman OY, Hashem M

Polymers (Basel), 2020 Dec 07;12(12).
PMID: 33297332 DOI: 10.3390/polym12122926

Conocarpus fiber is an abundantly available and sustainable cellulosic biomass. With its richness in cellulose content, it is potentially used for manufacturing microcrystalline cellulose (MCC), a cellulose derivative product with versatile industrial applications. In this work, different samples of bleached fiber (CPBLH), alkali-treated fiber (CPAKL), and acid-treated fiber (CPMCC) were produced from Conocarpus through integrated chemical process of bleaching, alkaline cooking, and acid hydrolysis, respectively. Characterizations of samples were carried out with Scanning Electron Microscope (SEM), Energy Dispersive X-ray (EDX), Fourier Transform Infrared-Ray (FTIR), X-ray Diffraction (XRD), Thermogravimetric (TGA), and Differential Scanning Calorimetry (DSC). From morphology study, the bundle fiber feature of CPBLH disintegrated into micro-size fibrils of CPMCC, showing the amorphous compounds were substantially removed through chemical depolymerization. Meanwhile, the elemental analysis also proved that the traces of impurities such as cations and anions were successfully eliminated from CPMCC. The CPMCC also gave a considerably high yield of 27%, which endowed it with great sustainability in acting as alternative biomass for MCC production. Physicochemical analysis revealed the existence of crystalline cellulose domain in CPMCC had contributed it 75.7% crystallinity. In thermal analysis, CPMCC had stable decomposition behavior comparing to CPBLH and CPAKL fibers. Therefore, Conocarpus fiber could be a promising candidate for extracting MCC with excellent properties in the future.

Matched MeSH terms: Hydrolysis
Fulltext Fabrication of Bio-Based Gelatin Sponge for Potential Use as A Functional Acellular Skin Substitute

Arif MMA, Fauzi MB, Nordin A, Hiraoka Y, Tabata Y, Yunus MHM

Polymers (Basel), 2020 Nov 13;12(11).
PMID: 33202700 DOI: 10.3390/polym12112678

Gelatin possesses biological properties that resemble native skin and can potentially be fabricated as a skin substitute for full-thickness wound treatment. The native property of gelatin, whereby it is easily melted and degraded at body temperature, could prevent its biofunctionality for various applications. This study aimed to fabricate and characterise buffalo gelatin (Infanca halal certified) crosslinked with chemical type crosslinker (genipin and genipin fortified with EDC) and physicaly crosslink using the dihydrothermal (DHT) method. A porous gelatin sponge (GS) was fabricated by a freeze-drying process followed by a complete crosslinking via chemical-natural and synthetic-or physical intervention using genipin (GNP), 1-ethyl-3-(3-dimethylaminopropyl) (EDC) and dihydrothermal (DHT) methods, respectively. The physicochemical, biomechanical, cellular biocompatibility and cell-biomaterial interaction of GS towards human epidermal keratinocytes (HEK) and dermal fibroblasts (HDF) were evaluated. Results showed that GS had a uniform porous structure with pore size ranging between 60 and 200 µm with high porosity (>78.6 ± 4.1%), high wettability (<72.2 ± 7.0°), high tensile strain (>13.65 ± 1.10%) and 14 h of degradation rate. An increase in the concentration and double-crosslinking approach demonstrated an increment in the crosslinking degree, enzymatic hydrolysis resistance, thermal stability, porosity, wettability and mechanical strength. The GS can be tuned differently from the control by approaching the GS via a different crosslinking strategy. However, a decreasing trend was observed in the pore size, water retention and water absorption ability. Crosslinking with DHT resulted in large pore sizes (85-300 µm) and low water retention (236.9 ± 18.7 g/m2·day) and a comparable swelling ratio with the control (89.6 ± 7.1%). Moreover no changes in the chemical content and amorphous phase identification were observed. The HEK and HDF revealed slight toxicity with double crosslinking. HEK and HDF attachment and proliferation remain similar to each crosslinking approach. Immunogenicity was observed to be higher in the double-crosslinking compared to the single-crosslinking intervention. The fabricated GS demonstrated a dynamic potential to be tailored according to wound types by manipulating the crosslinking intervention.

Matched MeSH terms: Hydrolysis
3-Chloropropane-1,2-diol (3-MCPD) in Soy Sauce: A Review on the Formation, Reduction, and Detection of This Potential Carcinogen

Lee BQ, Khor SM

Compr Rev Food Sci Food Saf, 2015 Jan;14(1):48-66.
PMID: 33401813 DOI: 10.1111/1541-4337.12120

Soy sauce, a dark-colored seasoning, is added to enhance the sensory properties of foods. Soy sauce can be consumed as a condiment or added during the preparation of food. There are 3 types of soy sauce: fermented, acid-hydrolyzed vegetable protein (acid- HVP), and mixtures of these. 3-Chloropropane-1,2-diol (3-MCPD) is a heat-produced contaminants formed during the preparation of soy sauce and was found to be a by-product of acid-HVP-produced soy sauce in 1978. 3-MCPD has been reported to be carcinogenic, nephrotoxic, and reproductively toxic in laboratory animal testing and has been registered as a chemosterilant for rodent control. 3-MCPD is classified as a possible carcinogenic compound, and the maximum tolerated limit in food has been established at both national and international levels. The purpose of this review is to provide an overview on the detection of 3-MCPD in soy sauce, its toxic effects, and the potential methods to reduce its concentration, especially during the production of acid-HVP soy sauce. The methods of quantification are also critically reviewed with a focus on efficiency, suitability, and challenges encountered in analysis.

Matched MeSH terms: Hydrolysis
Chitosan/(polyvinyl alcohol)/zeolite electrospun composite nanofibrous membrane for adsorption of Cr6+, Fe3+ and Ni2

Habiba U, Afifi AM, Salleh A, Ang BC

J Hazard Mater, 2017 Jan 15;322(Pt A):182-194.
PMID: 27436300 DOI: 10.1016/j.jhazmat.2016.06.028

In this study, chitosan/polyvinyl alcohol (PVA)/zeolite nanofibrous composite membrane was fabricated via electrospinning. First, crude chitosan was hydrolyzed with NaOH for 24h. Afterward, hydrolyzed chitosan solution was blended with aqueous PVA solution in different weight ratios. Morphological analysis of chitosan/PVA electrospun nanofiber showed a defect-free nanofiber material with 50:50 weight ratio of chitosan/PVA. Subsequently, 1wt.% of zeolite was added to this blended solution of 50:50 chitosan/PVA. The resulting nanofiber was characterized with field emission scanning electron microscopy, X-Ray diffraction, Fourier transform infrared spectroscopy, swelling test, and adsorption test. Fine, bead-free nanofiber with homogeneous nanofiber was electrospun. The resulting membrane was stable in distilled water, acidic, and basic media in 20 days. Moreover, the adsorption ability of nanofibrous membrane was studied over Cr (VI), Fe (III), and Ni (II) ions using Langmuir isotherm. Kinetic parameters were estimated using the Lagergren first-order, pseudo-second-order, and intraparticle diffusion kinetic models. Kinetic study showed that adsorption rate was high. However, the resulting nanofiber membrane showed less adsorption capacity at high concentration. The adsorption capacity of nanofiber was unaltered after five recycling runs, which indicated the reusability of chitosan/PVA/zeolite nanofibrous membrane. Therefore, chitosan/PVA/zeolite nanofiber can be a useful material for water treatment at moderate concentration of heavy metals.

Matched MeSH terms: Hydrolysis
Fulltext Characteristics of threadfin bream (nemipterus japonicas) hydrolysate produced using bilimbi (averrhoa bilimbi l.) protease and alcalase

Normah, I., Nur Anati, J.

International Food Research Journal, 2015;22(6):2259-2266.
MyJurnal

Threadfin bream (Nemipterus japonicas) muscle was hydrolysed using protease extracted from
bilimbi (Averrhoa bilimbi L.) fruit. This study was performed in order to compare the efficiency of bilimbi protease in producing threadfin bream protein hydrolysate with the commercial protease; alcalase 2.4 L. Initially, protease was extracted and then purified using 40% ammonium sulfate precipitation method. The proteolytic activity of the crude extract and purified protease was determined. Precipitation using 40% ammonium sulfate resulted in bilimbi protease specific activity of 2.36 U/mg and 23.13% recovery. Threadfin bream hydrolysate was prepared based on the pH-stat method by hydrolysis for 2 hrs. Hydrolysis using bilimbi protease produced 34.76% degree of hydrolysis (DH) and 3.75% yield while hydrolysis using alcalase resulted in 86.6% DH with 22.78% yield. Alcalase hydrolysate showed higher solubility than bilimbi protease hydrolysate at pH 7 with 70.87 and 32.16% solubility, respectively. Results also showed that protein content of threadfin bream hydrolysate produced using alcalase was higher (86.86%) than those produced using bilimbi protease (22.12%). However, both hydrolysates showed low moisture content between 3.93 to 7.00%. The molecular weight distribution analysis using SDS–PAGE indicated the distribution of smaller peptides especially in alcalase hydrolysate. Overall, the results showed that alcalase is more efficient enzyme choice than bilimbi protease for preparing threadfin bream hydrolysates. However, both hydrolysates could play an important role thus contribute to the food industry.

Matched MeSH terms: Hydrolysis
Fulltext Physicochemical properties of silver catfish (Pangasius sp.) frame hydrolysate

Amiza, M.A., Ow, Y.W., Faazaz, A.L.

International Food Research Journal, 2013;20(3):1255-1262.
MyJurnal

The physicochemical properties of silver catfish frame hydrolysate powder at three different degree of hydrolysis, DH43%, DH 55% and DH 68% were studied. The hydrolysates powder were obtained by hydrolysis using Alcalase®, centrifugation and spray drying of the supernatant. The study found that preparation of these hydrolysates affected the protein, ash and fat content as well as amino acid composition. As for essential amino acids, their values were generally considered as adequate as compared to the suggested essential amino acids profile of FAO/WHO. The results showed that SFHs were rich in lysine and glutamate. Hydrolysate at DH 68% exhibited better peptide solubility and water holding capacity. As degree of hydrolysis increased, emulsifying capacity and foaming capacity of the hydrolysate decreased. It was also found that the lightness in hydrolysate powder decreased with increase in degree of hydrolysis. This study shows that silver catfish frame hydrolysate has good solubility, good foaming properties and light colour profile, thus having high potential as food ingredient.

Matched MeSH terms: Hydrolysis
Fatty acid preference of mycelium-bound lipase from a locally isolated strain of Geotrichum candidum

Loo JL, Lai OM, Long K, Ghazali HM

World J Microbiol Biotechnol, 2007 Dec;23(12):1771-8.
PMID: 27517833 DOI: 10.1007/s11274-007-9427-2

Mycelium-bound lipase (MBL) was prepared using a strain of Geotrichum candidum isolated from local soil. At the time of maximum lipase activity (54 h), the mycelia to which the lipase was bound were harvested by filtration and centrifugation. Dry MBL was prepared by lyophilizing the mycelia obtained. The yield of MBL was 3.66 g/l with a protein content of 44.11 mg/g. The lipase activity and specific lipase activity were 22.59 and 510 U/g protein, respectively. The moisture content of the MBL was 3.85%. The activity of free (extracellular) lipase in the culture supernatant (after removal of mycelia) was less than 0.2 U/ml. The MBL showed selectivity for oleic acid over palmitic acid during hydrolysis of palm olein, indicating that the lipase from G. candidum displayed high substrate selectivity for unsaturated fatty acid containing a cis-9 double bond, even in crude form. This unique specificity of MBL could be a direct, simple and inexpensive way in the fats and oil industry for the selective hydrolysis or transesterification of cis-9 fatty acid residues in natural triacylglycerols.

Matched MeSH terms: Hydrolysis
Antioxidant and functional properties of protein hydrolysates obtained from squid pen chitosan extraction effluent

Shavandi A, Hu Z, Teh S, Zhao J, Carne A, Bekhit A, et al.

Food Chem, 2017 Jul 15;227:194-201.
PMID: 28274422 DOI: 10.1016/j.foodchem.2017.01.099

Squid pens were subjected to alkali hydrolysis to extract chitin and chitosan. Proteins present in the alkaline extraction wastewater were recovered at pH 3, 4, 5 and 6, and were subjected to hydrolysis by trypsin, pepsin and a bacterial protease called HT for 1, 2, 4 and 24h. Hydrolysis of the extracted proteins with either trypsin or HT generated more antioxidant activity than hydrolysis with pepsin. Higher ACE-inhibitory activity was generated in the trypsin and pepsin hydrolysates than in the HT hydrolysate. Squid pen protein recovered from chitosan processing waste alkaline solution can be a potential source of bioactive peptides for addition to foods. The antioxidant and ACE-inhibitory activities of the extracted proteins were initially low and increased upon incubation with the proteases. Pepsin generated significantly lower (P<0.05) antioxidant activities compared to trypsin and HT, while trypsin and pepsin hydrolysates exhibited higher ACE-inhibitory activity than HT (P<0.05).

Matched MeSH terms: Hydrolysis
Fulltext Kinetic modelling of ethanol fermentation process using cassava (Manihot esculenta) starch as carbon source

Low, C.Y., Hii, S.L., Leong, L.K., Yim, Y.Y., Tan, H.W.

ASM Science Journal, 2012;6(1):61-66.
MyJurnal

Cassava starch was used as feedstock for production of bioethanol by Saccharomyces cerevisiae. The cassava starch was hydrolyzed using commercial α-amylase and glucoamylase enzymes followed by a batch ethanol fermentation process using saccharified starch slurry. By using 110 g/L of reducing sugar from saccharified starch slurry, the ethanol yield was promising with maximum ethanol concentration of 20.6 g/L recorded after 55 hours of cultivation process. Three different models - the Logistic model, Luedeking-Piret-like equation and Gompertz equation - were used to characterize and explain the cell growth, reducing sugar consumption and production formation, respectively. The kinetic parameters were estimated by fitting the experimental data to the proposed models using non-linear regression analysis. The correlation coefficient r2 values for the Logistic model, Luedeking-Piret-like equation and the Gompertz equation were 0.994, 0.996 and 0.990, respectively. The high correlation coefficient values indicate that the proposed models were able to describe the ethanol fermentation process.

Matched MeSH terms: Hydrolysis
Fulltext Physicochemical characterisation and substrate specificity of purified β-1,6-glucanase from Trichoderma Longibrachiatum

Muskhazli Mustafa, Nor Azwady Abd. Aziz, Anida Kaimi, Nurul Shafiza Noor, Salifah Hasanah Ahmad Bedawi, Nalisha Ithnin

Pertanika Journal of Science & Technology, 2009;17(1):-.
MyJurnal

The β-1,6-glucanases are ubiquitous enzymes which appear to be implicated in the morphogenesis and have the ability to become virulence factor in plant-fungal symbiotic interaction. To our knowledge, no report on ß-1,6-glucanases purification from Trichoderma longibrachiatum has been made, although it has been proven to have a significant effect as a biocontrol agent for several diseases. Therefore, the aim of this study was to purify β-1,6- glucanase from T. longibrachiatum T28, with an assessment on the physicochemical properties and substrate specificity. β-1,3-glucanase enzyme, from the culture filtrate of T. longibrachiatum T28, was successively purified through precipitation with 80% acetone, followed by anionexchange chromatography on Neobar AQ and chromatofocusing on a Mono P HR 5/20 column. (One β-1,6-glucanase) band at 42kDa in size was purified, as shown by the SDS-PAGE. The physicochemical evaluation showed an optimum pH of 5 and optimum temperature of 50°C for enzyme activity with an ability to maintain 100% enzyme stability. Enzyme activity was slightly reduced by 10-20% in the presence of 20 mM of Zn2+, Ca2+, Co2+, Mg2+, Cu2+, Mn2+ and Fe2+. The highest β-1,6-glucanase hydrolysis activity was obtained on pustulan due to the similarity of β-glucosidic bonds followed by laminarin, glucan and cellulose. Therefore, it can be concluded that the characterization of ß-1,6-glucanase secreted by T. longibrachiatum in term of molecular weight, responsed to selected physicochemical factors and the substrate specificity are approximately identical to other Trichoderma sp.

Matched MeSH terms: Hydrolysis
Fulltext Biochemical properties of red tilapia (Oreochromis niloticus) protein hydrolysates

Shamloo, M., Bakar, J., Mat Hashim, D., Khatib, A.

International Food Research Journal, 2012;19(1):183-188.
MyJurnal

The amino-acid composition, 2, 2-Diphenyl-1-picryhydrazyl (DPPH) radical-scavenging activity, and peptide patterns of tilapia protein hydrolysates produced by the enzymatic hydrolysis of Alcalase (AH), Flavourzyme (FH) and Protamex (PH) for 5h using pH-stat method were studied. The ratio of essential amino acids to non-essential amino acids increased after hydrolysis in all samples; however, no significant differences among them were observed. AH had a highest (P < 0.05) DPPH radical-scavenging activity, but no significant difference in the DPPH between FH and PH was observed. SDS-PAGE patterns for all the hydrolysates showed significant (P < 0.05) reduction in the number and the intensity of the bands with increasing time of hydrolysis. Flavourzyme showed the lowest rate of hydrolytic activity towards the tilapia mince.

Matched MeSH terms: Hydrolysis
Fulltext Review article : phytase: application in food industry

Afinah, S., Yazid, A.M, Anis Shobirin, M.H, Shuhaimi, M.

International Food Research Journal, 2010;17(1):13-21.
MyJurnal

Phytates have been considered as a threat in human diet due to its antinutrients behaviour which
known as strong chelators of divalent minerals such as Ca2+, Mg2+, Zn2+ and Fe2+. Phytic acid has a potential for binding positively charged proteins, amino acids, and/or multivalent cations or minerals in foods. The resulting complexes are insoluble, difficult for humans to hydrolyze during digestion, and thus, typically are nutritionally less available for absorption. The reduction of this phytates can be achieved through both enzymatic and nonenzymatic removal. Enzymatic degradation includes addition of either isolated form of wild-type or recombinant exogenous phytate-degrading enzymes microorganisms in the food matrix. Non-enzymatic hydrolysis of phytate occurred in the final food during food processing or physical separation of phytate-rich parts of the plants seed. The application of phytase with respect to breadmaking process, probiotics, animal feed supplement and transgenic crops are emphasised in this paper.

Matched MeSH terms: Hydrolysis

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