Showing papers by "Lloyd T. Walker published in 2008"

Effect of processing on antioxidant contents in selected dry beans (Phaseolus spp. L.)

Abstract: Dry beans are rich sources of dietary fiber and phytochemicals such as flavonoids and phenolics. In the current study, we determined the effects of two processing methods (soaking and toasting) on total phenolics, flavonoids, proanthocyanidin and antioxidant potential by 2,2-diphenyl-1-picrylhydrazyl (DPPH) activity and ferric reducing antioxidant potential (FRAP) in selected dry beans (red kidney beans (K), black-eyed peas (B), pinto beans (P) and soy beans (S)). Total phenolics (mg/g dwb) expressed as gallic acid equivalents (GAE), total flavonoids (mg/g dwb) as catechin equivalents (CE) and proanthocyanidin expressed as leucocyanidin equivalent (mg LE/g) ranged from 3.42 to 7.21, 0.61 to 0.84 and 0.51 to 3.13 in raw beans; 3.58 to 6.94, 0.19 to 0.99 and 0.43 to 3.13 in soaked beans and 4.55 to 9.52, 0.23 to1.00 and 0.20 to 3.25 in toasted beans, respectively. FRAP (μg/g) in raw, soaked and toasted dry beans ranged from 0.00097 to 0.00424 while DPPH (T30) (%) ranged from 43.9 to 62.61. Our results indicate that processing methods (soaking and roasting) influenced total phenolic, flavonoid and antioxidant contents (DPPH, FRAP) in selected dry beans.

Chemopreventive Effects of Flax Seed Oil and Flax Seed Meal on Azoxymethane-Induced Colon Tumors in Fisher 344 Male Rats

Abstract: This study was designed to evaluate the anticarcinogenic effect of Flax Seed Meal (FSM) (10 and 20%) and Flax Seed Oil (FSO) (7 and 14%) on Azoxymethane (AOM)-induced colon tumors in Fisher 344 male rats during initiation (I), promotion (P) and Initiation + Promotion (I+P) stages of carcinogenesis. After an acclimatization period of 1 week, 14 groups of Fisher 344 male weanling rats, 3-4 week old (15 per group) were assigned to 2 control groups fed AIN 93G diet and AIN 93G + 14% soybean oil (SBO) (high fat control). The remaining 12 groups were assigned to 10 and 20% FSM (I, P and I+P) and 7 and 14% FSO (I, P and I+P). All rats received 16 mg kg-1 body weight of AOM at 7 and 8 week of age. At 20 weeks of age all animals were switched to AIN-93 M diets and at 45 week of age all rats were killed by CO2 asphyxiation. Tumor incidence (%) in colon of rats fed C (7 and 14%) was both 100. Tumor incidences for rats fed FSO (7 and 14%) at I, P and I+P were: 100, 100, 61, 60, 58 and 61, respectively and 80, 80, 66.6, 66.6, 66.6 and 31, respectively for rats fed FSM (10 and 20%) at I, P and I+P. Tumors per tumor-bearing ratios for groups fed C; 10 and 20% FSM (I, P and I + P) were 3.86, 1.28, 1.70, 1.75 and 1.0, 0.94, 0.64, respectively. In rats fed C (7 and 14%) and 7 and 14% FSO (I, P and I + P) T/TBR ratios were 3.86, 5.96; 1.4, 0.6, 0.6; 1.90, 0.8, 0.8, respectively. Glutathione-S-Transferase activity (a phase II detoxification enzyme) was significantly (p<0.05) higher in rats fed 10 and 20% FSM and 7 and 14% FSO compared to controls. The results of this study indicate that bioactive phytochemicals such as dietary fiber and lignans such as secoisolariciresinol diglycoside (SDG) found in flax seed meal and essential fatty acids such as α-linolenic acid (ALA) found in flax seed oil suppress colon tumors, particularly at the promotion stage and flax seed products may therefore be effective chemopreventive agents.

Enhancing the accuracy of area extraction in machine vision-based pig weighing through edge detection.

Abstract: The accuracy of extracting projected pig area is critical to the accuracy of the weight measurement of pigs by machine vision. The capability of both the conventional and the edge detection methods for extracting pig area was examined using the images of 47 pigs of different weights. Relationship between the threshold value and the extracted area was numerically analyzed for both methods. It was found that the accuracy of the conventional method depended heavily on the threshold value, while choice of threshold value in the edge detection approach had no influence on the extracted area over a wide range. In normal lighting conditions, both methods yielded comparable values of predicted weight; however, under variable light intensities, the edge detection method was superior to the conventional method, because the former was proven to be independent of light intensities. This makes edge detection an ideal method for area extraction during the walk-through weighing process where pigs are allowed to move around. Keywords: Area extraction, edge detection, threshold value, pig weighing, machine vision, image processing DOI: 10.3965/j.issn.1934-6344.2008.01.037-042 Citation: Wang Y, Yang W, Walker L, Rababah T M. Enhancing the accuracy of area extraction in machine vision-based pig weighing through edge detection. Int J Agric & Biol Eng. 2008; 1(1): 37

Improvement of oxidative stability of roasted peanuts by edible coatings and ultrasonication

Abstract: In this study, an innovative method was developed to improve the shelf life of roasted peanuts. Sonication was combined with edible coating for enhancing the oxidative stability of roasted peanuts. Georgia green runner peanuts were roasted, subjected to sonication and then coated with whey protein isolate (WPI), ZEIN and carboxymethyl cellulose (CMC). Relative to the control, the oxidative stability of roasted-coated samples was improved by 80, 38 and 5% for CMC, WPI and ZEIN coating, respectively, while roasted-sonicated-coated samples were improved by 91, 52 and 27% for CMC, WPI and ZEIN coating, respectively. Sonication prior to coating resulted in 11, 14 and 22% improvement beyond the CMC, WPI and ZEIN coatings, respectively. Texture analysis showed there were no significant differences (P < 0.05) in peanut texture between the treated and the control. Color results showed the HunterLab color parameters L, a, and b for most of the treatments did not have significant differences (P < 0.05) compared with the control. PRACTICAL APPLICATIONS Edible coatings used in this study (carboxymethyl cellulose, whey protein isolate and ZEIN) were capable of acting as oxygen barriers to reduce peanut lipid rancidity. This research demonstrated the potential of power ultrasound to remove lipids from the peanut surfaces and improve coating adhesion. The texture and the color of coated peanuts did not change over the storage period. This study indicated that edible coatings in combination with sonication provided an alternative way for improving the oxidative stability and eventually the shelf life and quality of roasted peanuts.

Antitumor and cytotoxic properties of dry beans (Phaseolus sp. L.): an in vitro and in vivo model

Abstract: The aim of this study was to examine antitumor effects of Kidney Beans (KB) on Azoxymethane (AOM) induced colon cancer and the cytotoxic effects of KB extracts on colon cancer cell lines (CaCO2) For ACF study, 12 Fisher 344 male rats were fed AIN-93G control diet (C) (n = 6) and 20% KB (n = 6), for 13 week In the EPTM two groups of rats (n = 14) were fed AIN-93G control diet (C) and 20% KB All rats received two s/c injections of AOM at 7 and 8 week of age at the rate of 16 mg kg-1 body weight in saline At 17 week (ACF) and 45 week of age (End-point) all rats were killed by CO2 asphyxiation For lactate dehydrogenase (LDH) assay, cells were incubated (24 and 48 h) with selected concentrations (05-25 mg/100 mL) of KB extract Total number of ACF was 158 and 72 for groups fed C and 20% KB Tumor size (mm) and TBR for C and 20% KB were 650; 116 and 38; 144, respectively LDH release (%) in CaCO2 cells after 24 and 48 h incubation with KB extracts ranged from 138 to 628 and 235 to 841, respectively Feeding KB significantly (p<005) reduced the incidence of AOM induced colon tumorigenesis and KB extracts demonstrated cytotoxic effects on colon cancer cell lines (CaCO2)