Tangtua J.,Kamphaeng Phet Rajabhat University |
Techapun C.,Chiang Mai University |
Pratanaphon R.,Chiang Mai University |
Kuntiya A.,Chiang Mai University |
And 5 more authors.
Chiang Mai Journal of Science | Year: 2017
The intracellular pyruvate decarboxylase enzyme (PDC, EC 188.8.131.52) extract from Candida tropicalis TISTR 5350 was compared by two different purification methods using ammonium sulphate and acetone precipitation. The total volumetric PDC activity and percentage recovery (yield) of precipitated PDC based on 50% (v/v) cold acetone were significantly higher (1.13 ± 0.02 U/ml and 98.27 ± 2.98 %, respectively) than any other concentration levels of acetone used. Furthermore, all concentration levels of cold acetone also yielded a much higher specific PDC activity than the precipitate obtained using the 40 to 60% (w/v) ammonium sulphate saturation (0.75 ± 0.08 U/mg protein). The precipitated enzyme in buffer solutions from the 50% (v/v) acetone was subsequently freeze dried. Freeze drying of the precipitated PDC by cold acetone resulted in the specific PDC activity of 1.57 ± 0.02 U/mg protein and differed statistically (p ≤ 0.05) from the crude enzyme extract (control). © 2017, Chiang Mai University. All rights reserved.
Pichaiyongvongdee S.,Suan Dusit Rajabhat University |
Rattanapun B.,Kamphaeng Phet Rajabhat University |
Haruenkit R.,King Mongkut's University of Technology Thonburi
Kasetsart Journal - Natural Science | Year: 2014
Pomelo (citrus grandis (L.) Osbeck) is one of the popular Thai fruits, which is well known for having high antioxidant properties. The total polyphenol content and antioxidant properties (1,1 diphenyl-1-picrylhydrazyl, DPPH) and ferric reducing antioxidant power (FRAP)) were determined in seven of the many pomelo cultivars growing in Thailand—namely, Kao Numpueng (KNP), Thong Dee (TD), Kao Paen (KP), Kao Yai (KY), Tha Knoi (TK), Pattavee (PV) and Kao Tanggwa (KTG). Different parts of the fruit tissue consisting of flavedo, albedo, segment membranes and seeds, were tested. The results indicated that the total polyphenol content was highest in the seeds in all cultivars (3,108.78–4,957.97 μg.g-1), while for the other parts, the ranking in decreasing order was albedo (1,176.58–3,384.81 μg.g-1), flavedo, (1,096.27–2,163.63 μg.g-1) and segment membranes (825.68–2,266.66 μg.g-1), respectively. The antioxidant properties (DPPH) were highest in the seeds, while for the other parts, the ranking in decreasing order was albedo, flavedo and segment membranes. By cultivar, Thong Dee (TD) produced the highest total polyphenol content and antioxidant properties (DPPH and FRAP) in the flavedo and seeds. Tha Knoi (TK) had the highest total polyphenol content and antioxidant properties (DPPH and FRAP) in the albedo and segment membranes. Kao Tanggwa (KTG) had the highest antioxidant properties (DPPH) in the seeds. A linear relationship between the total polyphenol content and the DPPH has a coefficient of determination (R2) of 0.702, and for FRAP the R2 was 0.659. Thus, edible tissues of pomelo could be a source of bioactive compounds which is high in antioxidant properties and suitable for industrial processing. © 2014 Kasetsart J. (Nat. Sci.) All rights received.
Kreungngern D.,Kamphaeng Phet Rajabhat University |
Chaikham P.,Phranakhon Si Ayutthaya Rajabhat University
International Food Research Journal | Year: 2016
This work purposed to evaluate the qualities of Chao Kuay (Mesona procurebens Hemsl.) jelly combined with 3% and 6% (w/v) of different gelling agents including potato flour (commercial formula or control group), agar and carrageenan. Rheological behaviors, textural profiles, color parameters and sensory attributes of the products were determined. In this study, we found that types and levels of gelling agents had a significant effect on the qualities of Chao Kuay jelly. Color parameters indicated that jelly mixed with 3% potato flour was apparently darker than the other batches. The gel had a medium density of branched-structure, indicating by the viscoelastic behaviors. From textural properties and sensory scores, the results confirmed that 3% potato flour addition could be appropriate to ensure the good gel qualities for Chao Kuay jelly production.
Ummartyotin S.,Thammasat University |
Pechyen C.,Thammasat University |
Toommee S.,Kamphaeng Phet Rajabhat University
Russian Journal of Applied Chemistry | Year: 2016
ZnO was successfully prepared by the conventional synthetic route. Polyvinylpyrrolidone was used as soft-template to synthesize ZnO with controllable size and shape. It was found that ZnO was synthesized with average crystal size of 49 nm, as reported by an X-ray diffraction experiment. Scanning electron microscopy and transmission electron microscopy confirmed the hexagonal shape of the as-synthesized ZnO. The thus prepared ZnO colloidal particles exhibited numerous opportunities for numerous applications. © 2016, Pleiades Publishing, Ltd.
Moonchai S.,Chiang Mai University |
Rakpuang W.,Kamphaeng Phet Rajabhat University
Modelling and Simulation in Engineering | Year: 2015
This paper presents a modified grey model GMC(1,n) for use in systems that involve one dependent system behavior and n-1 relative factors. The proposed model was developed from the conventional GMC(1,n) model in order to improve its prediction accuracy by modifying the formula for calculating the background value, the system of parameter estimation, and the model prediction equation. The modified GMC(1,n) model was verified by two cases: the study of forecasting CO2 emission in Thailand and forecasting electricity consumption in Thailand. The results demonstrated that the modified GMC(1,n) model was able to achieve higher fitting and prediction accuracy compared with the conventional GMC(1,n) and D-GMC(1,n) models. © 2015 Sompop Moonchai and Wanwisa Rakpuang.
Tangtua J.,Kamphaeng Phet Rajabhat University
International Food Research Journal | Year: 2014
An enzymatic biotransformation process based on extracted pyruvate decarboxylase (PDC) overcomes the problem of by-product benzyl alcohol production. Seven methods of cells disruption which included application of glass beads, freezing/thawing sequence, silver nanoparticles, ultrasonication, freezing/thawing sequence with glass beads, freezing/thawing sequence with silver nanoparticles, and freezing/thawing sequence with ultrasonication were investigated to choose the best method for partial isolation of PDC from Candida tropicalis TISTR 5350. Ultrasonication was an effective method for cells disruption with the corresponding specific PDC activity of 0.36 ± 0.01 U/mg of protein. Ultrasonication method should thus be selected as the method of choice to preserve enzyme activity. The PDC from C. tropicalis TISTR 5350 released from ultrasonic cells disruption method was prepared for partial purification in comparison with 40-60% (w/v) ammonium sulphate and 50% (v/v) acetone precipitation techniques. Specific PDC activity, purification and percentage recovery (yield) of precipitated PDC enzyme based on 50% (v/v) acetone at 4°C were higher (0.53 ± 0.02 U/mg protein, 1.24 ± 0.10, and 94.41 ± 2.12 %, respectively) than the precipitation obtained using the 40 to 60% (w/v) ammonium sulphate saturation (0.49 ± 0.01 U/mg protein, 1.13 ± 0.07, and 92.87 ± 2.50%, respectively). The result indicated that the precipitation of PDC using the 50% (v/v) acetone was the most effective strategy for partially purifying PDC and suitable for application in a commercial process which had a relatively low cost and simple process. © All Rights Reserved.
Pichaiyongvongdee S.,Suan Dusit Rajabhat University |
Rattanapun B.,Kamphaeng Phet Rajabhat University
Kasetsart Journal - Natural Science | Year: 2015
The pomelo albedo was selected from three cultivars—Kao Nampung (KNP), Thongdee (TD) and Kao Yai (KY). KNP was a suitable cultivar for preparing dietary fiber powder because it had high crude fiber content and the limonin and naringin contents were lower than for TD and KY. Limonin and naringin are the main bitter components of pomelo albedo which need to be reduced. Three chemicals were used to reduce the bitterness of the pomelo albedo—NaCl (1%, 3%, 5%), CaCO3 (1%, 3%, 5%) as well as various pH levels using 0.1 N NaOH solution (pH 7, 8 and 9). The results showed that all chemicals treatment could reduce the limonin and naringin contents (P ≤ 0.05) but adjusting the organoleptic quality to pH 7 had the highest odor score and the lowest score for bitterness. Two drying methods were studied: freeze drying was conducted at -40 °C for 14 hr and the three conditions for tray drying were 50 °C for 5.5 hr, 60 °C for 4.5 hr and 70 °C for 2 hr. The freeze dried pomelo albedo powder had better physical, chemical and functional properties than the samples that were tray dried (P ≤ 0.05). The water holding capacity and swelling capacity of the dietary fiber pomelo albedo powder were compared with commercial cellulose (carboxymethyl cellulose). It was found that the pomelo albedo dietary fiber powder had better functional properties than the commercial cellulose based on scanning electron microscopy. Thus, dietary fiber pomelo albedo powder can be used as a functional ingredient or in industrial applications using food products. © 2015, Kasetsart University. All rights reserved.
Klinhom P.,Kamphaeng Phet Rajabhat University |
Klinhom J.,Chiang Mai University |
Senapa J.,Chiang Mai University |
Methawiwat S.,Kamphaeng Phet Rajabhat University
International Food Research Journal | Year: 2015
The objective of this research was to evaluate the effects of immersion marination with citric acid, calcium chloride and combined mixture of citric acid and calcium chloride solutions on Semimembranosus meat quality traits. Meat cuts obtained from culled cows were marinated with 0.05 M citric acid, 0.2 M calcium chloride or the combined mixture of these two compounds for 24 hr. Non- marinated meat served as control. Application of calcium chloride to the marination (either solely or in combination) improved water holding capacity (WHC) thus reduced cooking loss and shear force values. Meat marinated in citric acid solution showed high exudative during cooking and was not significantly different in shear force value compared to the unmarinated samples. Lightness was higher (paler) in all marinated meat samples. The a* values showed that marinated meat with citric acid solution had less red intensity. Lower of yellow intensity (b* value) appeared in the meat samples marinated with calcium chloride and the combined mixture. The sensory attribute evaluation showed that the highest scores for juiciness and tenderness were for calcium chloride and the combined mixture. The lowest flavor score was found in the meat marinated with citric acid solution and reported as sour. Sample treated with calcium chloride revealed no detrimental effect on meat flavor and odour. The evidence in the present study indicates that calcium chloride marinate solution increases juiciness and tenderness of meat from culled cow.
Chaikham P.,Phranakhon Si Ayutthaya Rajabhat University |
Kreungngern D.,Kamphaeng Phet Rajabhat University |
Apichartsrangkoon A.,Chiang Mai University
International Food Research Journal | Year: 2013
The effect of microwave radiation densities (100 and 300 W) and hot air velocities (5 and 10 m/s) on the physical and biochemical properties as well as consumer acceptability of dried longan fleshes was investigated. It was found that the moisture in the longan dried by microwave-air convective oven was displaced faster than the traditional drying. The firmnesses of longan dried at 300 W were higher than those in longan dried at 100 W. The loss of lightness (L parameter) or the increase of redness (a* parameter) in longan dried at 300 W could be associated with the increase of Maillard browning and caramelization reactions. Lowest microwave power density could be preserved total phenolic compounds, gallic acid and ellagic acid in the products greater than conventional- and high microwave power-drying techniques. Panelists were most satisfied with sensory qualities of the dried longan using microwave power 100 W with air velocity 5 and 10 m/s. It was concluded that drying at 100 W and air velocity 5 m/s was acceptable for the production of dried longan fleshes.
PubMed | Thammasat University and Kamphaeng Phet Rajabhat University
Type: | Journal: Data in brief | Year: 2016
The objective of this research is to produce the low-cost activated carbon from