• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.583-587
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• 2006

Aqueous solutions of sugar alone or in the presence of lysine were gamma irradiated at 0, 5, 10, 20 and 30 kGy at room temperature. Absorbances at 284 nm as an indicator of intermediate stage of non -enzymatic browning reaction increased with irradiation dose in both the solution of sugar or lysine alone and sugar-lysine mixed solution. Absorbances at 420 nm as indicator of browning increased in the irradiated sugar-lysine mixed solutions although no browning was observed in the irradiated solution of sugar or lysine alone. The degree of browning of the irradiated sugar-lysine mixed solution increased with irradiation dose and was dependent on the type of sugar. For sugar-lysine mixed solution irradiated at 30 kGy, the browning had the following order of intensity: sucrose>fructose>arabinose>xylose>glucose. However, the sugar loss of irradiated sugar lysine mixed solution had a following order of intensity: glucose>fructose>sucrose>xylose>arabinose. The reducing power of the non-reducing sugar, sucrose, was produced by gamma irradiation. The present results indicated that gamma irradiation leads to a non-enzymatic browning reaction (carbonyl-amine reaction) in an aqueous system.

• Journal of Animal Science and Technology
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• v.62 no.4
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• pp.521-532
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• 2020

The production performance of broiler breeder hens in response to different levels of total lysine during the early laying period was investigated. A total of 126 Ross 308 parent stock hens were offered one of seven dietary treatments formulating elevated contents of total lysine ranging from 0.55% to 0.79% (0.04 scale; 133 g of feed) from 23 to 29 weeks of age. Each treatment had six replicates with three birds per pen. Body weight was recorded triweekly and eggs were collected and weighted at 9:00 am daily. One hen from each pen was euthanized to collect blood samples and visceral organs were harvested and weighed. Egg production, egg weight and egg mass were lower (p < 0.05) in hens offered a diet containing 0.55% total lysine compared to those fed the diet containing higher total lysine. Hens offered a diet containing 0.71%, 0.75%, and 0.79% total lysine had greater (p = 0.008) egg production rate compared to those offered a diet containing lysine less than 0.71%. The number of total eggs produced tended to be greater (p = 0.083) in hens offered a diet containing 0.71 and 0.75% total lysine compared to the other treatments. The number of settable egg production was higher (p < 0.001) in hens offered a diet contacting 0.79% total lysine compared to those fed the diet containing lower levels of total lysine. The relative weights of oviduct and ovary were lower (p < 0.05) in hens offered a diet containing 0.59% total lysine compared to the other treatments. No difference found in body weight, the number of total eggs, double-yolk eggs and abnormal shell eggs among the treatments. The urea nitrogen, estradiol-17 beta and progesterone in plasma were not affected by treatments. Based on linear- and quadratic-plateau models, total lysine requirements for egg production, settable egg production and egg mass at the early laying period were to be 0.73%, 0.77%, and 0.71%, respectively. Modern broiler breeder hens likely require higher total lysine than NRC recommendation in a diet for enhancing productivity during the early-laying period.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.12
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• pp.1785-1793
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• 2008

Fifty-four PIC barrows were used to evaluate the effects of lower dietary lysine content and energy level on carcass characteristics and meat quality in slaughter pigs. Pigs were allotted to one of three treatments by body weight with six replicate pens in each treatment. The dietary treatments for body weights of 20-50 kg, 50-80 kg and 80-90 kg were as follows, respectively: control diet (digestible energy 14.22 MJ/kg, lysine/DE 0.67 g/MJ, 0.53 g/MJ and 0.42 g/MJ); a low lysine group (digestible energy 14.22 MJ/kg, lysine/DE 0.49, 0.38 and 0.30 g/MJ); and a low lysine-low energy group or low nutrient group (digestible energy 13.11 MJ/kg, lysine/DE 0.49, 0.38 and 0.30 g/MJ). The daily weight gain, daily feed intake and feed efficiency were calculated in the overall growth period (nearly 12 weeks). Meanwhile, carcass characteristics and meat quality were evaluated at 60 and 90 kg body weight respectively. During the overall growth trial, lowering dietary lysine and nutrient level both decreased weight gain (p<0.05) and feed efficiency (p<0.01). At 60 kg body weight, decreasing dietary lysine and nutrient level noticeably decreased dressing percentage (p<0.01) and back fat depth at last rib of PIC pigs (p<0.01), but enhanced marbling scores (p<0.10), intramuscular fat content (p<0.10) and water loss rate (p<0.01) of the longissimus dorsi muscle. At 90 kg body weight, lean percentage (p<0.01) was evidently reduced by both lowering lysine content and nutrient level in the diet. However, the shoulder back fat depth (p<0.05) and marbling scores of the loin eye muscle (p<0.05) were increased; Lowering dietary nutrient level could improve back fat depth of 10th rib (p<0.01) and last rib (p<0.01), intramuscular fat content (p<0.10), redness (p<0.01) and water loss rate of the loin eye muscle (p<0.05), but decrease loin area (p<0.05). Finally, when comparing the 60 kg and 90 kg slaughter weights, it was found that the shoulder back fat depth (p<0.01, p<0.10), 6th-7th rib (p<0.01, p<0.01), 10th-rib (p<0.01, p<0.01) and last rib back fat depth (p<0.01, p<0.01) of the low lysine and low nutrient group were all obviously increased comparing with the control group. Taken together, the results showed that decreasing dietary lysine content and nutrient level increased intramuscular fat content and water loss rate of longissimus dorsi muscle; On the other hand, both lowering dietary lysine and nutrient level markedly compensated to increase back fat deposition in the later finishing period (body weight from 60 to 90 kg) in contrast to the control group.

• Microbiology and Biotechnology Letters
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• v.11 no.3
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• pp.175-180
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• 1983

Thialysine significantly inhibited the growth of wild type strain Gondida utilis NCYC-359. In the absence of thialysine, the culture reached stationary phase after 24hr, however, in the presence of 0.5% thialysine, the culture reached stationary phase after 40hr, respectively. Effect of amino acid or vitamin was investigated on recovery of the growth of wild type strain from thialysine inhibition. Glycine, methionine, arginine and tryptophan recovered growth inhibition by thialyslne to some extent. However, vitamins were inert. Especially, lysine at one eighth concentration of thialysine recovered almost fully the growth inhibition. Thialysine resistant mutants were induced from the parent strain of Condida utilis NCYC-359 by NTG treatment. Colonies of thialysine resistant mutants were obtained on agar minimal medium supplemented with 0.1-0.5% thialysine. The frequency of thialysine resistant mutants induced by the first mutation was the highest at 0.1% The wild strain produced no appreciable lysine extracellularly. However, almost thialysine resistant mutants excreted appreciably. Lysine excretion increased after repeated mutation. Finally, of the thialysine resistant mutants induced by NTG, Condida utilis TRN-4006 was obtained. This strain excreted lysine (400$\mu\textrm{g}$/$m\ell$) into the medium with a concomitant decrease of lysine in the intracellular pool.

• Korean Journal of Food Science and Technology
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• v.8 no.3
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• pp.129-135
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• 1976

The amino acid compositions of polished barley grain were investigated for 16 varieties by using amino acid autoanalyzer and simple correlation analysis between them and between protein and amino acid per protein was done. 1) Limiting amino acid is lysine, leucine and phenylalanine are high but threonine and tyrosine are low. Total essential amino acids is high. 2) Protein is significantly correlated negatively with lysine arginine, total basic amino acids (at p=0.01) and threonine, alanine, aspartic acid (at p=0.05) and positively with phenylalanine (at p=0.01) proline and cystine (at p=0.05). 3) Lysine is positively and significantly correlated with arginine and aspartic acid indicating that aspartic acid is probable precursor of lysine and that high yielding varieties or fertilization for high yielding decrease aspartic acid pool resulting low lysine. 4) Lysine content is positively correlated with dye binding capacity (at p=0.01). 5) Tryptophan is positively (at p=0.01) and significantly correlated with histidine, total basic amino acids and arginine. 6) In essential amino acids lysine, tryptophan, threonine and valine simultaneously increase or decrease while aromatic amino acids, sulfur contained amino acids, isoleucine and leucine do so together.

• Journal of Pharmaceutical Investigation
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• v.22 no.4
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• pp.323-326
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• 1992

$Poly({\varepsilon}-carbobenzoxy\;L-lysine)/poly(ethylene oxide)/poly({\varepsilon}-carbobenzoxy\;L-lysine)$ (LEL) block copolymers containing $poly({\varepsilon}-carbobenzoxy\;L-lysine)$ (PCLL) as the A component and poly(ethylene oxide) (PEO) as the B component were investigated as drug delivery matrix. PCLL homopolymer and LEL block copolymer microspheres containing anticancer drug, cytarabine, were prepared by a solvent evaporation process and the release patterns of cytarabine from the microspheres were investigated in vitro. The size of PCLL homopolymer and LEL block copolymer microspheres was ranged from $0.2\;{\mu}m$ to $1\;{\mu}m$ in diameter and the shape of the microspheres was almost round. The release pattern of cytarabine from the block copolymer microspheres was dependent on the mole % of PEO of the block copolymers.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2004.06a
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• pp.236-241
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• 2004

In Escherichia coli, L-lysine biosynthetic pathway is composed of nine enzymatic reactions. It has been well established that most of the lysine biosynthetic genes are regulated by the lysine availability, even though they are all scattered around the chromosome without forming any multigenic operon structure. However, no transcriptional regulatory mechanism has been identified except for the activation of lysA gene by the LysR. In this study, changes in transcriptome profiles of wild type cells and lysR deletion mutant cells grown in the absence or presence of lysine were investigated by using DNA microarray technique. Microarray data analysis revealed three groups of genes whose expression varies depending on the availability of lysine or LysR or both. To further examine the regulatory patterns of lysine biosynthetic genes, lacZ operon fusions were constructed and their expression was measured under various conditions. Obtained results strongly suggest that there is an additional regulatory mechanism which senses the lysine availability and coordinates gene expression.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.6
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• pp.939-943
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• 2007

Two experiments were conducted to determine the lysine requirement of straight-run broiler chickens ($Hubbard{\times}Hubbard$) during the period 4-21 (Exp. 1) and 21-40 (Exp. 2) days of age. Experiments were conducted during the summer months (June-August) in open-sided houses, thus exposing chicks to chronic heat stress. Daily min-max temperature averaged $28-40^{\circ}C$ (Exp. 1) and $28-36^{\circ}C$ (Exp. 2). Lysine deficient basal diets were formulated to contain low-nutrient-density, i.e., 2,700 kcal per kg ME, 18.6% CP (Exp. 1), and 2,750 kcal per kg ME, 17.1% CP (Exp. 2), to mimic typical commercial broiler diets used in Pakistan. Diets were supplemented with L-lysine HCl to provide total lysine level ranging from 0.85 to 1.10% (six increments) and 0.72 to 1.02% (six increments), respectively in Exp. 1 and 2. Live performance data were subjected to quadratic analysis and requirement was defined as the level achieving 95% of maximum or minimum values. Lysine requirements were found to be 0.98 and 0.97% total lysine, respectively, for gain and feed efficiency during 4-21 days, and 0.87% total lysine for both gain and feed efficiency during 21-40 days of age. Calculated on a digestible lysine basis, the estimates were 0.85 and 0.84%, respectively, for gain and feed efficiency during 4-21 days of age; and 0.75% for gain and feed efficiency during 21-40 days of age.

• Microbiology and Biotechnology Letters
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• v.16 no.3
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• pp.175-181
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• 1988

To produce L-lysine from cellulosic substrate, the intergeneric protoplast fusion between Cellulomonas flavigena and Corynebacterium glutamicum, Cellulomonas flavigena and Brevibacterium flavum was performed. The fusion frequencies were 1.9$\times$10$^{-6}$ to 2.1$\times$10$^{-6}$ for the regenerated protoplasts when two parental strains were treated with 30% of polyethyleneglycol (M.W.6000) containing 5 mM EDTA at 3$0^{\circ}C$ for 30 min. Two fusants, FCB3 and FCC 19 were finally selected by comparision of their genetic stability and L-lysine productivity. The properties of fusants-DNA con-tent, G＋C content and L-lysine productivity-were investigated. The DNA content of fusants was greater than those of the parental strain and their G＋C contents are equal to half of total G＋C con-tent of two parental strains. The fusants showed high productivity of L-lysine from carboxy methyl cellulose as substrate.

• Journal of Microbiology and Biotechnology
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• v.25 no.7
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• pp.1108-1113
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• 2015

Cadaverine (1,5-diaminopentane) is an important industrial chemical with a wide range of applications. Although there have been many efforts to produce cadaverine through fermentation, there are not many reports of the direct cadaverine production from lysine using biotransformation. Whole-cell reactions were examined using a recombinant Escherichia coli strain overexpressing the E. coli MG1655 cadA gene, and various parameters were investigated for the whole-cell bioconversion of lysine to cadaverine. A high concentration of lysine resulted in the synthesis of pyridoxal-5'-phosphate (PLP) and it was found to be a critical control factor for the biotransformation of lysine to cadaverine. When 0.025 mM PLP and 1.75 M lysine in 500 mM sodium acetate buffer (pH6) were used, consumption of 91% lysine and conversion of about 80% lysine to cadaverine were successfully achieved.