Effect Of L-proline Research Articles

Effect of L-proline on sperm quality during cryopreservation of boar semen

L-proline has been reported to be useful in semen cryopreservation. However, its use has rarely been reported in the freezing of boar semen. The objective of this study was to evaluate the effects of different concentrations of L-proline (0, 10, 30, 50, and 90 mM) on the quality of boar semen after freezing and thawing. Semen samples from boars (n = 6) were frozen using freezing extenders with added concentrations of L-proline. Total sperm motility, progressive motility, survival time at 37 °C, acrosome integrity, mitochondrial activity, DNA integrity, the content of the lipid peroxidation product malondialdehyde (MDA), total antioxidant capacity (T-AOC) and, expression levels of apoptosis protein (cleaved caspase 3 and Bax) were evaluated after thawing. The results showed that total sperm viability (73.96% vs. 63.58%) and progressive motility (56.88% vs. 47.26%) after thawing were significantly higher in the 10 mM L-proline treatment group than in the control group. The survival time at 37 °C and the total motility of sperm in the 10 mM group within one hour after thawing were significantly higher than in the control group. Acrosome integrity and mitochondrial activity of sperm in the 10 mM group were significantly higher than those in the control, 50 mM, and 90 mM groups. The DNA integrity rate in the 10 mM group was significantly higher than in the control group. The L-proline treatment did not affect sperm MDA content or T-AOC. The expression levels of apoptosis protein (cleaved caspase 3 and Bax) in the 10 mM L-proline supplemented group were lower than those in the control group. In conclusion, the freezing extender containing 10 mM L-proline improved semen quality after freezing and thawing and thus would be a useful reagent for boar semen cryopreservation.

Effect of L-proline and L-glutamic acid on productivity of winter rapeseed

Effect of L-proline and L-glutamic acid on productivity of winter rapeseed

Effect of organic ligands (l-Proline and l-Methionine) on growth, structural, vibrational, crystalline perfection, SHG efficiency, microscopic and optical properties of KDP single crystals

The effect of l-Proline (LP) and l-Methionine (LM) doping on the various properties of KDP single crystals grown by slow evaporation solution technique has been investigated. The external morphology of the grown crystals was found to vary due to different dopants and doping concentrations. The change in powder X-ray diffraction intensity patterns due to doping shows the lattice distortion within resolution limit and confirms that there is no extra phase. Further, the same was confirmed by FT-Raman analysis. Infra red microscopic study also exhibits the effectiveness of doping in terms of varying surface morphology. Crystalline perfection of KDP crystals with LP and LM doping was examined by high-resolution X-ray diffraction. This shows very interesting features on the ability of accommodating the dopants in the crystalline matrix. Second harmonic generation efficiency was also found to be in similar fashion as of crystalline perfection. The optical transparency of doped crystals was tested.

L-Prolin zur Behandlung von degenerativen Gelenkerkrankungen

L-Proline is important in the biosynthesis of collagenic tissues. By the enzymatic transformation of L-Proline, Hydroxyproline is formed. L-Proline and Hydroxyproline stabilize the fibrils of the mature collagen. Collagen is one of the main components of the extracellular matrix of hyaline cartilaginous tissue. In a clincial study with athletes it was possible to show, that a dose of 3 g L-Proline/day is an effective pain therapy. Experience from a practice of a general practitioner proves the therapeutic effect of L-Proline in the case of degenerative joint diseases.

L-Proline as an efficient and reusable promoter for the synthesis of coumarins in ionic liquid

The effect of L-proline as a promoter on the condensation reaction of salicylaldehyde or its derivatives with ethyl acetoacetate in neutral ionic liquid [emim]BF4 was studied. All reactions were carried out under mild reaction conditions and achieved high yields. Moreover, the ionic liquid containing L-proline could be recycled and reused for several times without noticeably decreasing in productivity. The results show that the L-proline-[emim]BF4 system has a potential in contribution to the development of environmentally friendly and inexpensive processes in organic syntheses.

NaCl stress in rice seedlings: effects of L-proline, glycinebetaine, L-and D-asparagine on seedling growth

The effect of L-proline, glycinebetaine, L-and D-asparagine on rice seedling growth under NaCl stress was investigated. Glycinebetaine and L-asparagine were not effective in reducing NaCl inhibition in shoot growth of rice seedlings. L-Proline and D-asparagine were found to be able to reduce shoot growth inhibition under NaCl stress. However, L-proline, glycinebetaine, D- and L-asparagine further enhanced NaCl inhibition of root growth.

Influence of carbon sources on the stimulatory effect of l-proline on 5′-inosinic acid production

Abstract The relationship between the stimulatory effect of l -proline on IMP production and glucose/fructose ratio was examined with mutant KY10895 of Corynebacterium ammoniagenes. The stimulatory effect of l -proline on IMP production decreased with an increase in fructose. The reason was ascribed to the assimilation ratio of l -proline. The optimum glucose/fructose ratio for the stimulatory effect of l -proline on IMP production was 100 0 .

Effect of l-proline on mushroom tyrosinase

The kinetic parameters for the catecholase and cresolase activities of mushroom tyrosinase have been determined both in the presence and in the absence of l-proline. l-Proline does not modify the kinetic parameters ( V maxand K m ) of the catecholase activity, but modifies the V max of the cresolase activity and affects the lag period and the steady-state rate of this activity. These results can be explained taking into account the complex mechanism proposed for tyrosinase.

Primary afferent depolarization and changes in extracellular potassium concentration induced by L-glutamate and L-proline in the isolated spinal cord of the frog

To test the hypothesis that l-proline acts as an antagonist on glutamate receptors [17, 18], the interation between l-glutamate and l-proline was studied in the isolated spinal cord of the frog. Glutamate at concentrations of 10 −6 −5 × 10 −3 mol/l depolarized the primary afferent fibres and increased extracellular potassium concentration, [K +] e by 0.3–4 mmol/l. Repeated applications lead to inactivation of the response. l-Proline at 5 × 10 −3 mol/l, also depolarized the primary afferents and increased [K +] e by 0.5–2 mmol/l, but there was only a slight decrease of the effects after repeated application. The effects were additive when the amino acids were applied simultaneously. The effect of l-proline was still present when it was applied during inactivation of the glutamate receptors. This suggests that l-glutamate and l-proline act on different receptors.

The fermentative production of L-proline. V. Purification and properties of glutamate kinases required for L-proline and L-glutamine biosynthesis in Brevibacterium flavum.

Glutamate kinase activity was separated into two different protein fractions, i.e. glutamate kinase I and II, through the purification of twice carried out ammonium sulfate fractionation and DEAE-cellulose column chromatography, and both specific activities were raised nearly ten times higher. Each kinase was found to catalyze kinase reaction stoichiometrically. The optimum pH range of both kinases was between 7.5 and 8.0. The Km value of kinase I and II for l-glutamatic acid were 1.7 × 10−2 m and 3.1 × 10−2 m respectively. Both kinases were specific for only l-glutamic acid, and formed l-glutamine from l-glutamic acid by the addition of ammonium ion instead of NH2OH. No effect of l-proline on either kinase was detected. l-Glutamine markedly inhibited kinase II competitively with l-glutamic acid. Kinase I catalyzes the so-called forward transfer reaction more effectively than kinase II, whereas kinase II catalyzes the reverse transfer reaction four times effectively. Kinase II seems to be more closely rel...

Iontophoretic and autoradiographic studies on the role of proline in nervous transmission.

Iontophoretic experiments with the aid of multibarreled micropipettes demonstrate a reversible depressant effect ofl-proline on the spontaneous discharge of Purkinje cells in the cat cerebellar cortex. The failure of a specific interaction with strychnine and bicuculline leads to the conclusion that proline acts neither on receptors for “glycine-like” nor on receptors for “GABA-like” amino acids. Autoradiographic investigations reveal a differential distribution of radioactivity after injection of3H-leucine and3H-proline into the cerebellar cortex. After leucine injection, high grain density can be observed over Stellate, Basket, Golgi and especially Purkinje cells. In contrast after application of3H-proline, the silver grains are concentrated primarily in the tissue adjacent to the Purkinje cells, mainly in the supraganglionic region and between these faintly labelled cerebellar cells. These results suggest the possibility that proline is involved in inhibitory neurotransmission.