• Asian-Australasian Journal of Animal Sciences
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• v.11 no.3
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• pp.209-216
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• 1998

The paper presented here is aimed at increasing knowledge on purine metabolism in ruminants and hence the quantification of microbial cells entering the small intestine from urinaη excretion of purine derivatives. Nucleic acid metabolisms of micro-organisms in the rumen, digestion and absorption of nucleic acids entering the intestines, metabolisms of absorbed and endogenous purines involving de novo synthesis of nucleic acids in the ruminants host, and the relationship between absorbed and excreted purines are reviewed. Principal concerns about an amount of purine derivatives excreted in urine in relation to a change in purine-N: total-N ratios in rumen microbes that leave the rumen are discussed. The use of urinary excretion of purine derivatives as an indicator of the amount of microbial biomass leaving the rumen has to be done with some caution since it may be impossible to get a representative sample of microbes entering the intestine and thus yield estimates are relative rather than absolute.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.3
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• pp.465-468
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• 1992

Urinary purine derivatives and creatinine excretion was measured in a total of 4 white Alpine sheep. They were given diets 718 to 1060 g/kg dry matter (DM) of roughage. The crude protein content of this diets was on average $93.87{\pm}5.57g$ in kg DM. Purine derivatives-N excretion increased linearly with incremental DM intake and was significantly correlated (n = 16) with amounts of digestible organic matter (DOM) intake: allantoin-N (mg) = 1.205 (${\pm}0.070$) $\times$ DOM (g) - 136.709 (${\pm}37.399$), r = 0.9770, RSD = 22.97; uricacid-N (mg) = 0.131 (${\pm}0.041$) $\times$ DOM (g) + 11.380 (${\pm}21.881$), r = 0.6306, RSD = 13.44; Hypoxanthine-N (mg) = 0.049 (${\pm}0.014$) $\times$ DOM (g) - 28.640 (${\pm}7.708$), r = 0.6544, RSD = 4.73; total purine derivatives-N (mg) = 1.385 (${\pm}0.083$) $\times$ DOM (g) - 90.261 (${\pm}44.552$), r = 0.9706, RSD = 27.47. Microbial protein synthesis per kg DOM was estimated of 113 g. The urinary creatinine-N excretion was on average 9.10 mg/kg live weight (LW) with a standard error of 0.12 mg creatinine-N per kg LW. The excretion of creatinine excreton was not related to feed intake. Daily creatinine excretion (mg/d) was calculated from individual LW measurements and the average creatinine excretion (mg/kg LW). It was possible to predict the daily urinary purine derivatives excretion (r = 0.9720 for allantoin, r = 0.9886 for total purine derivatives) from the ratio of purine derivatives (mg/100 ml) and creatinine (mg/100 ml) in the urine and the daily creatinine excretion.

• Archives of Pharmacal Research
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• v.12 no.1
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• pp.1-4
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• 1989

6-Arylamino-3,7-dihydro-3,7-dimethy-2-oxo-1H-purine and 2-arylimino-6-arylamino-3,7-dihydro-3,7-dimethyl-1H-purine were obtained in a one-pot reaction when 3,7-dihydro-3,7-dimethyl-1H-purine-3,6-dione, phosphorus pentaoxide, triethylamine hydrochloride and appropriate amine amino are heated at $170^{\circ}$. Some derivatives were tested for their antitumor activity.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.347-355
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• 2006

A study was conducted to predict the rumen microbial protein production based on urinary excretion of purine derivatives in buffaloes fed a diet of wheat straw and concentrate (40:60) at four fixed levels of feed intake. (95, 80, 60 and 40% of preliminary voluntary feed intake) following experimental protocol of IAEA (Phase I). The buffaloes were allocated according to a $4{\times}4$ latin square design. The urinary allantoin, uric acid, total PD excretion (mmol/d) in treatments L-95, L-80, L-60 and L-40 was 20.13, 16.00, 12.96 and 9.17; 1.88, 2.12, 2.11 and 2.15; 22.01, 18.12, 15.07 and 11.32, respectively and were significantly (p<0.05) different among treatments except for uric acid. The rate of PD excretion (mmol/d) was positively correlated with the digestible organic matter intake. Variations were observed in PD and creatinine concentration in spot samples collected at 6-hour interval. However, daily PD:Creatinine ratio (PDC index) appears to be a reasonably good predictor of microbial-N supply. The contribution of basal purine excretion to total excretion of purine derivatives (PD) was determined in pre-fasting period followed by a fasting period of 6 d (Phase II). Daily PD and creatinine excretion (mmol/kg $W^{0.75}$) during fasting averaged 0.117 and 0.456 respectively for buffaloes. The excretion rates of PD decreased significantly (p<0.01) during fasting compare to pre-fasting period, the urinary creatinine excretion remained almost similar. Except for creatinine, plasma concentration of target parameters significantly (p<0.01) declined during fasting. Likewise, glomerular filtration rate (GFR) and renal clearance of allantoin and uric acid also decreased. Based on the PD excretion rates during fasting and at different levels of feed intake obtained in this study, a relationship between daily urinary PD excretion (Y-mmol) and microbial purine absorption (X-mmol) was developed for buffaloes as Y = 0.74X+0.117 kg $W^{0.75}$. The microbial N supply (g/kg DOMI) remained statistically similar irrespective of dietary treatment. The results showed that excretion of urinary purine derivatives is positively correlated with the levels of feed intake in Murrah buffaloes and thus, estimation of urinary purine derivatives and PDC index could be used to determine microbial nitrogen supply when there is large variation in level of feed intake.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.8
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• pp.1201-1207
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• 2007

This study compared the recovery rate of intrajugular-administered allantoin in the urine and saliva between swamp buffaloes and zebu cattle to examine whether it could explain the lower excretion rate of urinary purine derivatives (PD) in the buffaloes. Three male swamp buffalo yearlings, with an average body weight of $349{\pm}40.35$ kg, and three Thai native cattle ($154{\pm}3.26$ kg) of similar age and sex were used in the study. Animals were kept in individual pens and fed at a maintenance energy level with a diet containing 65% monk bean husk (Vigna radiata) as roughage and 35% concentrates. Allantoin solution was infused into the jugular vein in four incremental rates equivalent to 0, 5, 10 and 15 mmol/d and urine was collected daily in acidified form. Daily PD excretion was linearly correlated with intrajugular allantoin infusion in both species. The relationship between daily urinary PD excretion (Y, mmol/d) and intrajugular allantoin infused (X, mmol/d) was $Y=0.75{\pm}0.318X+22.45{\pm}2.98$ ($r^2$ = 0.36, n = 12, MSE = 38.02, CV = 21.9, p<0.01) for swamp buffaloes and $Y=0.96{\pm}0.10X+15.93{\pm}0.92$ ($r^2$ = 0.91, n = 12, MSE = 3.60, CV = 8.27, p<0.01) for zebu cattle. The salivary PD concentration was not correlated with intrajugular allantoin infusion in both species, with values for buffaloes numerically lower than those for cattle. The present study reconfirmed previous studies that buffaloes have a lower plasma PD excretion rate via the renal route and a significant proportion (22%) of the plasma PD loss is via the saliva. However, results of our present and previous studies suggest that differences in purine base (PB) metabolism between buffaloes and zebu cattle occur before the purine compounds reach the plasma pool.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.4
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• pp.364-370
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• 1997

Four local cattle were ($145{\pm}9.7kg$) used in a $4{\times}4$ Latin square design to study the effect of different levels of rumen degradable protein (RDP) in straw based ration on purine derivatives excretion and microbial N supply in cattle. The four rations were formulated at the same amount of energy but varying RDP approximately 50 (U0), 75 (U1), 100 (U2) and 150 (U3) percent levels of RDP requirement for maintenance. They were fed ranged from 101 to 304 g RDP/d. Apparent digestibility of all nutrients increased significantly (p < 0.01) in cattle fed ration U2 than other rations. Rumen $NH_3-N$ concentration increased from 43 to 130 mg/l in response of RDP intake. Purine derivatives excretion increased significantly (p < 0.01) with incremental level of 203 g RDP/d (U2) intake and positively correlated (r=0.69, p < 0.01, n=16) with amount of RDP intake. The rates of rumen microbial N supply were 16.8, 27.2, 39.1 and 32.9 g/d for rations U0, U1, U2 and U3 respectively. Efficiency of microbial N supply (EMNS) per kg of DOMR were 19.0, 25.3, 33.0, and 28.6 g and per MJ of ME. Intake were 0.62, 1.00, 1.44 and 1.21 g for U0, U1, U2 and U3 respectively and highest results were obtained in cattle fed U2 ration. Results of this study suggest that PD excretion and EMNS were increased as incremental level of RDP intake (U2) in local cattle.

• YAKHAK HOEJI
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• v.41 no.2
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• pp.181-186
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• 1997

A series of 7-deazahypoxanthine and 7-deazaadenine derivatives[6,7.8.9.10,13] as purine antagonists was prepared. The pyrrolidine-5-one derivatives[4,11] were treated vith $(C_2H_5)_3OBF_4$ to give 3- aryl-5-ethoxy-2H-3,4-dihydropyrrole[5,12], which were converted to 7-aryl-7,8-dihydro-7(9H)-deazahy-poxanthine[6,7,8,9,10] and 7-phenyl-2-methyl-7,8- dihydro-7(9H)-deazaadenine[13].

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.6
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• pp.904-907
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• 1999

The experiment was aimed at studying the effect of ruminal $NH_3-N$ levels on ruminal fermentation, microbial population, urinary purine derivative excretion, digestibility and rice straw intake in swamp buffaloes. Five, 3 to 4 years old, rumen fistulated swamp buffaloes were randomly assigned according to a $5{\times}5$ Latin square design to rceive five different intraruminal infusions of $NH_4HCO_3$ (0, 150, 300, 450 and 600 g/d) on a continuous daily basis. Rice straw as a roughage was offered ad libitum while concentrate was given at 0.8% BW daily. The results were that as levels of $NH_4HCO_3$ increased, ruminal $NH_3-N$ concentrations increased from 7.1 to 34.4 mg%. The highest digestibility and voluntary straw intakes were found at 13.6 to 17.6 mg% ruminal $NH_3-N$ levels; straw intake was highest at 13.6 mg%. Total bacterial and protozoal counts linearly increased as the ruminal $NH_3-N$ increased and were highest at 17.6 mg%. Total urinary purine derivatives and allantoin excretion were highest (44.0, 37.4 mM/d) at 17.6 mg% ruminal $NH_3-N$. Highest total VFAs (115 mM) were obtained a 13.6 mg% ruminal $NH_3-N$ while blood urea nitrogen significantly increased as ruminal $NH_3-N$ increased. The results from this experiment suggest that optimum ruminal $NH_3-N$ in swamp buffaloes is higher than 13.6 mg%, for improving rumen ecology, microbial protein synthesis, digestibility and straw intake.

• Archives of Pharmacal Research
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• v.17 no.2
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• pp.60-65
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• 1994

Reaction of c-chloro-9-benzyl-8-(methylthio)purine 3 with primary amines afforoded, the comesponding 6-(substitutedamino)purines 4a-g. The latter products when methylated with methyl iodide yielded smoothly $N^3$-methyl purinium iodide salts 5a-f rather than the probable $N^1\;and\;N^7$-derivatives. 9-Benzyl-3-methyl-6-(methylmino)-8-(methylthio)purine 8 was obtained upon treating the purinium iodide 5a with alkali. Most of the synthesized compounds were screened for their antitumor activity.

• Korean Journal of Pharmacognosy
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• v.9 no.1
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• pp.1-9
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• 1978

The principle of Fourier Transform Nuclear Magnetic Resonance and its usefulness in the fields of pharmacy and biological sciences are described. 1. The $^1H\;and\;^{13}C$ NMR spectra of triostin A and its mixture with purine derivatives were taken. From the analysis of the spectra it has established that triostin A, which exists in two symmetric conformers in chloroform solution, forms complexes only with purine derivatives by the participation of one of the conformers. 2. Also, the $^{13}C$ NMR spectra of "intact" substances in the field of pharmacognosy were taken. From the spectra it was suggested that the method is very useful for natural product research in cooperation with the chemical method.