Hyeon-Jung Kang

Creation of Resveratrol-Enriched Rice for the Treatment of Metabolic Syndrome and Related Diseases

Resveratrol has been clinically shown to possess a number of human health benefits. As a result, many attempts have been made to engineer resveratrol production in major cereal grains but have been largely unsuccessful. In this study, we report the creation of a transgenic rice plant that accumulates 1.9 µg resveratrol/g in its grain, surpassing the previously reported anti-metabolic syndrome activity of resveratrol through a synergistic interaction between the transgenic resveratrol and the endogenous properties of the rice. Consumption of our transgenic resveratrol-enriched rice significantly improved all aspects of metabolic syndrome and related diseases in animals fed a high-fat diet. Compared with the control animals, the resveratrol-enriched rice reduced body weight, blood glucose, triglycerides, total cholesterol, and LDL-cholesterol by 24.7%, 22%, 37.4%, 27%, and 59.6%, respectively. The resveratrol-enriched rice from our study may thus provide a safe and convenient means of preventing metabolic syndrome and related diseases without major lifestyle changes or the need for daily medications. These results also suggest that future transgenic plants could be improved if the synergistic interactions of the transgene with endogenous traits of the plant are considered in the experimental design.

Growth performance and hematological traits of broiler chickens reared under assorted monochromatic light sources

A study was conducted to investigate the effect of different monochromatic lights on growth performance and hematological response of growing broiler chickens. A total of 360 one-day-old broiler chicks were randomly divided into 6 lighting treatments, which were replicated 6 times with 10 chicks in each replicate. Six light treatments include incandescent bulbs (as a control) and light-emitting diode white light, blue light, red light, green light, and yellow light (YL). The birds were provided with similar nutritional specifications and environmental management facilities, except for the lights throughout the experimental period. Growth performance was evaluated in terms of BW, BW gain, feed intake, and feed conversion ratio at weekly intervals. At the end of 5 wk, 2 birds from each replicate were randomly selected for blood collection to determine hematological response. The BW and feed intake was numerically higher in YL at 5 wk of age. But interestingly, this did not result in improved feed conversion ratio in YL; nevertheless, numerical values were lower in YL at 5 wk (P > 0.05). Red blood cells, blood platelet count, and percent hematocrit were numerically higher under YL, whereas white blood cell counts and percent hemoglobin remained unaffected due to light treatments. It was concluded that monochromatic light is a potential light source that might provide a beneficial effect on growth performance but is inconclusive for hematological measures of broilers.

Influence of monochromatic light on quality traits, nutritional, fatty acid, and amino acid profiles of broiler chicken meat

The role of monochromatic lights was investigated on meat quality in 1-d-old straight-run broiler chicks (n = 360), divided into 6 light sources with 6 replicates having 10 chicks in each replicate. Six light sources were described as incandescent bulbs (IBL, as a control) and light-emitting diode (LED) light colors as white light (WL), blue light, red light (RL), green light, and yellow light. Among LED groups, the RL increased the concentration of monounsaturated fatty acids (P < 0.001), saturated fatty acids (P < 0.001), and the saturated:polyunsaturated fatty acid ratio (P < 0.001), but reduced the concentration of polyunsaturated fatty acid, n-3 fatty acid, and n-6 fatty acid. The IBL increased the n-3 and sulfur-containing amino acids but reduced the n-6:n-3 nonessential amino acids. The WL improved the concentration of most of the essential amino acids (P < 0.01) and nonessential amino acids (P < 0.01) of breast meat. It can be extracted that the light produced by LED responded similar to the IBL light in influencing nutrient contents of meat. Moreover, LED is not decisive in improving fatty acid composition of meat. However, the role of IBL in reducing n-6:n-3 ratio and enhancing n-3 cannot be neglected. Among LED, WL is helpful in improving essential and nonessential amino acid contents of broiler meat.

Various levels and forms of dietary α-lipoic acid in broiler chickens: Impact on blood biochemistry, stress response, liver enzymes, and antibody titers

The present experiment was conducted to evaluate the impact of various levels and forms of α-lipoic acid (ALA) on blood biochemistry, immune and stress response, and antibody titers in broiler chickens. The four levels (7.5, 15, 75, and 150 ppm) and 2 sources (powder, P-ALA and encapsulated, E-ALA) of ALA along with negative (C-) and positive control (C+; contains antibiotics) diets consisted of 10 dietary treatments, and these treatments were allocated to 1,200 1-d-old chicks and were replicated 12 times with 10 birds per replicate. Among the blood biochemistry parameters, creatinine levels were almost 3 times lower in E-ALA-supplemented diets compared to the C- diet (0.09 vs. 0.25 mg/dL; P<0.0001). Neither level nor source of ALA affected blood urea nitrogen (BUN), total protein (TP), albumin, globulin, or albumin to globulin ratio (AGR). The supplemented diets decreased serum levels of the liver enzymes aspartate-aminotransferase (AST; P<0.006) and alanine-aminotransferase (ALT; P<0.0003). The Newcastle disease virus (NDV) antibody response in supplemented groups was poor at day zero (P<0.0001) but increased by d 14 (P<0.03). Birds did not respond to infectious bronchitis virus (IBV) vaccination at any observed stage (P>0.05). The concentration of cortisol was reduced in chickens fed ALA-supplemented diets as compared to the C- diet (P<0.001). Results suggest that ALA-supplemented diets ameliorated blood biochemistry profiles and immune responses and reduced stress in broiler chickens. The encapsulated form of ALA was more effective than the powder form.

Comparative analysis of physicochemicals and antioxidative properties in new red rice (Oryza sativa L. cv. Gunganghongmi)

The main objectives of this study were to investigate physicochemicals and antioxidant activities of new red rice (Oryza sativa cv. Gunganghongmi (GH)) by comparing normal brown (Nampyeongbyeo, NB) and reported red rice (Jukjinjubyeo, JB) in Korea. The nutritional constituents, including protein, oil, sugar, fatty acid, GABA, and γ-oryzanol were not significantly different between normal brown and colored rice. However, the ethanol extract of GH showed the highest phenolic content (24.7 ± 1.3 mg g−1). The ethanol extracts of GH showed higher scavenging activities against DPPH (0.2 mg mL−1 = 62.1 ± 2.5%) and ABTS (0.2 mg mL−1 = 63.2 ± 3.5%) radicals. Moreover, GH more inhibited LPS-induced nitric oxide (NO) production (13.2 ± 1.4 μM) than JB (18.3 ± 2.3 μM) and NB (22.1 ± 1.4 μM) at the same concentration (0.2 mg mL−1) without cytotoxicity. These results suggest that new red rice (GH) would be considered to be new functional rice due to its anti-oxidative effect and high nutrition.

Effect of heating system using a geothermal heat pump on the production performance and housing environment of broiler chickens.

A geothermal heat pump (GHP) is a potential heat source for the economic heating of broiler houses with optimum production performance. An investigation was conducted to evaluate the effect of a heating system using a GHP on production performance and housing environment of broiler chickens. A comparative analysis was also performed between the GHP system and a conventional heating system that used diesel for fuel. In total, 34,000 one-day-old straight run broiler chicks were assigned to 2 broiler houses with 5 replicates in each (3,400 birds/replicate pen) for 35 d. Oxygen(,) CO(2), and NH(3) concentrations in the broiler house, energy consumption and cost of heating, and production performance of broilers were evaluated. Results showed that the final BW gain significantly (P < 0.05) increased when chicks were reared in the GHP broiler house compared with that of chicks reared in the conventional broiler house (1.73 vs. 1.62 kg/bird). The heating system did not affect the mortality of chicks during the first 4 wk of the experimental period, but the mortality markedly increased in the conventional broiler house during the last wk of the experiment. Oxygen content in the broiler house during the experimental period was not affected by the heating system, but the CO(2) and NH(3) contents significantly increased (P < 0.05) in the conventional broiler house compared with those in the GHP house. Fuel consumption was significantly reduced (P < 0.05) and electricity consumption significantly increased (P < 0.05) in the GHP house compared with the consumption in the conventional house during the experiment. The total energy cost of heating the GHP house was significantly lower (P < 0.05) compared with that of the conventional house. It is concluded that a GHP system could increase the production performance of broiler chicks due to increased inside air quality of the broiler house. The GHP system had lower CO(2) and NH(3) emissions with lower energy cost than the conventional heating system for broiler chickens.

Anti-pigmentation effect of serotonin alkaloid isolated from Korean barnyard millet ( Echinochola utilis )

Investigation of the melanogenesis inhibitory effect of barnyard millet grain extracts (BME) led to isolation of compounds against mushroom tyrosinase and B16 melanoma cells. Chromatography yielded five phenolic compounds, among which n-p-coumaroyl serotonin (1, CS) exhibited potent non-competitive inhibition (IC50 =8.8 μM) compared with that of kojic acid (IC50=14.6 μM) against mushroom tyrosinase. More importantly, CS decreased melanin content to eight times lower (IC50 =11.6 μM) in B16 melanocytes than that of feruloyl serotonin (2, FS, IC50 =86.5 μM) without cytotoxicity. CS significantly inhibited the protein expression of tyrosinase, tyrosinase-related protein-1 (TRP-1), TRP-2, and microphthalmia-associated transcription factor using immunoblotting. Furthermore, molecular docking simulations were also carried out to investigate the structure related to the inhibitory activities. Therefore, BME can be used as a natural source of depigmentation to prevent melanogenesis.

Effects of stock density on the laying performance, blood parameter, corticosterone, litter quality, gas emission and bone mineral density of laying hens in floor pens

The effects of stocking density on the performance, egg quality, leukocyte concentration, blood biochemistry, corticosterone levels, bone mineral density, and noxious gas emission of laying hens were investigated. Eight hundred 34-week-old Hy-Line Brown laying hens (Gallus gallus domesticus) were randomly assigned to one of 4 treatments, each of which was replicated 4 times. Four stocking densities, including 5, 6, 7, and 10 birds/m2, were compared. A commercial-type basal diet was formulated to meet or exceed nutrient recommendations for laying hens from the National Research Council. The diet was fed to the hens ad libitum for 8 wk. Results indicated that hen-day egg production, egg mass, and feed intake were less for (P < 0.01) 10 birds/m2 stock density than other stock densities. Production rate of floor and broken eggs and eggshell strength were greater (P < 0.01) for 10 birds/m2 stock density than other stock densities. There were no significant differences in the level of leukocytes among densities. However, heterophils and the H/L ratio were greater (P < 0.01) for 10 birds/m2 than in stock density of 6 or 7 birds/m2. Serum corticosterone was greater (P < 0.01) 10 birds/m2 than stock density than other stock densities. Litter moisture and gas emission (CO2 and NH3) were greater (P < 0.01) for 10 birds/m2 than stock density than 6 and 7 birds/m2 stock density. Bone mineral content was not influenced by increasing stock density. However, bone mineral density was less (P < 0.05) for 10 m2 stock density than other stock densities. These results indicate that increasing the density beyond 5 birds/m2 elicits some negative effects on laying performance of Hy-Line brown laying hens.

Effect of Flammulina velutipes on spent-hen breast meat tenderization

An experiment was carried out to investigate the effects of powdered vegetable dip sauces to improve the tenderness of spent-hen breast meat. Our overall purpose was to find lower-priced materials for the tenderization of spent-hen breast meat. The spent-hen breast meat was dipped into vegetable powder for 24 h at 4°C, and then the samples were analyzed. In the results for vegetable-powder treated samples, those treated with papain and pineapple had higher (P ≤ 0.05) myofibrillar fragmentation indices compared with those of the other samples. The kiwi-, pineapple-, and Flammulina velutipes-powder (winter mushroom) treated samples had new peptides of about 32 kDa and degradation to 30 kDa. Also, the Flammulina velutipes-powder treated samples showed new peptides of 15 kDa. These data imply that Flammulina velutipes is superior for common use than papain or pineapple for the tenderization of spent-hen meat.

Improvement of Selection Efficiency for Bacterial Blight Resistance Using SNP Marker in Rice

Discovery of single nucleotide polymorphisms (SNPs), including small insertions and deletions, is one of the hot topics in genetic research. The most common type of sequence variant consists of single base differences or small insertions and deletions at specific nucleotide positions. Significance of SNPs in rice is increasing for genetic research, positional cloning and molecular breeding. 170 lines and 194 lines derived from Sangjuchalbyeo/HR13721-53-3-1-3-3-2-2 Were used for Searching SNP markers related to bacterial blight resistance. Sangjuchalbyeo is susceptible to bacterial blight, but HR13721-53-3-1-3-3-2-2 has Xa1 gene resistant to bacterial blight. Individual lines were inoculated with race of bacterial blight and resistant or susceptible was evaluated after 3 weeks from inoculation. The genotypes of population were analysed by PCR-RFLP for SNP marker developing. The segregation of population showed almost 3:1, 1:1 ratio, respectively. Analysis of genotype using SNP marker is capable of confirming resistance for race and genotype through amplifying the gene using 16PFXal primer and digested the PCR product with Eco RV. There were close relation between resistance test for race and SNP marker genotype. Especially, DNA analysis using SNP marker is capable of judging homozygote/heterozygote in population compared with resistant test for Kl race. So, it seems to improve the selection efficiency in disease resistant breeding.