The structure of N-(p-chlorophenyl)-maleamic acid, (I), was brie¯y reported by Prasad & Mandal (1978), with an R value of 0.16, using photographic X-ray diffraction data. The struc- ture has now been re®ned using diffractometer X-ray data and the results are presented here. We have previously reported the structure of a related compound, N-(p-tolyl)maleamic acid (Prasad et al., 2002). The two structures are similar but not exactly isostructural. The substitution of CH 3 by a Cl atom has
The solution of maleic anhydride (0.025 mol) in toluene (25 ml) was treated dropwise with the solution of 2-chloro-4- nitroaniline (0.025 mol) also in toluene (20 ml) with constant stirring. The resulting mixture was stirred for about 30 min and set aside for an additional 30 min at room temperature for the completion of reaction. The mixture was then treated with dilute hydrochloric acid to remove the unreacted 2-chloro-4-nitroaniline. The resultant solid N-(2-chloro-4-nitro- phenyl)-maleamic acid monohydrate was filtered under suction and washed thoroughly with water to remove the unreacted maleic anhydride and maleic acid. It was recrystallized to constant melting point from ethanol. The purity of the compound was checked and characterized by its infrared spectra.
N-(2-aminophenyl)maleamic acid (Santos-Sa´nchez et al., 2007). Compound (I) differs from related structures in the conformation of its carboxylic acid group. In (I), the –COOH group adopts syn conformation (i.e. the O3 C10—O2—H2O torsion angle = 0 ) whereas an anti conformation is noted in related structures (the equivalent torsion angle is close to 180 ). This disparity is a result of O—H
The structure of N-(p-tolyl)maleamic acid, (I), was reported previously by Prasad & Sinha (1978), using photographic X-ray diffraction data, with an R value of 0.16. The structure has now been re®ned using single-crystal X-ray diffraction data and the results are presented here.
The structure of the title compound, (I), comprises an essen- tially ¯at molecule displaying a typical maleic acid intramol- ecular hydrogen bond. In this interaction, the O O distance of 2.465 (2) AÊ is short, whereas the re®ned OÐH distance of 1.11 (3) AÊ is longer than expected. The corresponding H O distance of 1.37 (3) AÊ indicates that the H atom is essentially delocalized between the two O atoms. An intermolecular NÐ H O association exists from the amide to the carboxylic acid carbonyl O atom, while several CÐH O close contacts are observed around the maleamic acid O atoms. The title compound is a precursor to the corresponding maleimide.
Electrochemical polymerization of N-Creatininyl maleamic (NCM) acid was carried out on stainless steel plate electrode in a protic medium of monomer aqueous solution using electrochemical oxidation procedure in electrochemical cell. Fourier Transform Infrared FT-IR Spectroscopy has examined the structure of synthesized polymer. The anti-corrosion action of polymer was investigated on stainless steel in 0.2M Hydrochloric acid solution at temperatures range (293-323) K. by electrochemical polarization method. In addition, reinforce the anticorrosion of coating polymer by nanomaterial (TiO 2 ) or (ZnO bulk and nano) by adding these nanomaterials to monomer
The widespread reports in recent years on useful biological activities of tritepenes, indicate their potential. Triterpenes are found to show antitumor, anticancer, antiviral, antimicrobial, anti-inflammatory activity (Mahato et al., 1997). In the present investigation hexane and chloroform extracts of Rhizophora apiculata were found to contain triterpene hydrocarbon, urs-12 ene (>30 and 10%, respectively). Ursolic acid was reported to be cytotoxic against A- 549, L-1210 and KB tumour cells (Yamagishi et al., 1988). 23-Hydroxy-3-oxo-urs-l 2-en- 28- oic acid was found to exhibit anti-ulcer properties (Fourie et al., 1989). So, the antimicrobial activity of present study may be due to terpenes and sesquiterpenes (Bryon and Eric, 2003). The fatty acids composition of the leaf is also studied by FAME analysis. It mainly contains palmitic acid as major constituent (54.65%). Two important poly unsaturated fatty acids i.e., Linoleic acid (w-6, 1.54%) and 9, 11-0ctadecadienoic acid (3.25%) are also present along with arachidic acid (2.56%).
esters (FAME) mixture obtained was analyzed using a Shimadzu Gas Chromatograph (Model: GC-2010, Shimadzu, Japan) with a Flame ionization detector (FID) on a split injector. A SP-2560 capillary column (100 m long x 0.25 mm i.d) was used for FAME analysis. Oxygen free nitrogen was used as a carrier gas at a flow rate of 33.9 ml/minute. The initial oven temperature was 140 °C for 5 minutes which was slowly raised to 240 °C at a rate of 4 °C / min. and finally held at 240 °C for 20 minutes. The injector and detector temperature were finally set at 260 °C. Volume injected 1 µl; split ratio, 1:30. Peaks obtained were identified by comparison of their retention times with that of standard fatty acid methyl esters. The percentage compositions of the samples under investigation were computed from the G.C peak areas. The results obtained were placed in Table 1.
Our data showed that all six phenolic acids tested possess a dose-dependent and time-dependent inhibitory antiproliferative effect on T47D cells. Nevertheless, a dif- ferential effect for each phenolic acid was found, with IC 50 values varying from the nanomolar to the picomolar range. The time course of phenolic acids varies equally. Indeed, caffeic acid exerts its action later than other phenolic acids, suggesting a different mode of action. Ferulic acid, structurally related to caffeic acid, shows a bimodal effect, with a short time component and a long time component. Finally, all other phenolic acids show a half-maximal effect, achieved after 2 days. Comparing the structures of the dif- ferent phenolic acids, presented in Fig. 1, our data suggest that the two hydroxyl groups on the phenolic ring and the three carbon side chains are both essential for the antiproliferative activity. The shortening of the side chain produces a loss of the antiproliferative activity, which is more apparent in both the methylation of one or both –OH group(s) and the p-OH substitution found in syringic acid and sinapic acid. In addition, shortening of the side chain confers an increased IC 50 value, indicating a possible increase of the transmembrane transit of the compounds or, alternatively, an increased interaction with an unknown membrane constituent.
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In human nutrition, dietary fibers are un-degradable by mammalian en- zymes, and are therefore potentially available for fermentation by mi- cro-organisms living in the gastrointestinal tract. It is thought that these fer- mentable carbohydrates affect fermentation by stimulating the growth or metabolism of specific bacterial species, which are potentially beneficial for health. Hence in this study three gut associated microbes— Escherichia coli , Bacillus subtilis , and Lactobacillus acidophilus were made to ferment the non-digestible fraction of Otili — Sphenostylis stenocarpa , a well-established underutilized wild bean with high economic importance. After 18 hours’ fer- mentation period short chain fatty acids (SCFAs) and medium chain fatty acids (MCFAs) were detected and evaluated by GC-MS analysis. Metabolic products were relatively dependent on the fermenter. This present study af- firmed butyric acid as the main SCFAs after 18 hours’ fermentation. The clinical significance of thirteen other MCFAs detected and quantified was also explored thus conferring a valuable prebiotic on Otili .
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Formaldehyde is the simplest fragment of sug- ars. Its formation was confirmed in many studies concerning sugar degradation. Its scission from 1-endiols yields lower aldose as the second prod- uct. Formaldehyde was also suggested as a product of cleavage of C 1 –C 2 bond of the acyclic adduct of hydroperoxide anion to ketoses (Isbell et al. 1973). Acetaldehyde could hypothetically arise by retro-aldol cleavage of intermediates having structure motives of 1-deoxy-2,3-dihydroxy-4-oxo or 2-deoxy-3-hydroxy-1-oxo (Figure 4). In fact, no report introducing any certain six or five carbon precursor with this structure motive is available. However, both aldehydes are known to be scission products of some lower carbonyls (Figure 3). For example, cleavage of triosoreductone provides for- maldehyde and glyoxal, while scission of 1-en-1,2- diol of acetol gives formaldehyde and acetaldehyde (Velíšek 2002). Rössner (2004) predicted the formation of both aldehydes during the cleavage of glyoxal and subsequent disproportionation of the fragments formed. Analogously, acetaldehyde and formaldehyde could also form from methyl- glyoxal with simultaneous formation of the cor- responding acid. Furthermore, pyruvic acid may be formed by oxidation of methylglyoxal and can consecutively decarboxylate yielding acetaldehyde. The identification of pyruvic acid in our model systems supports this reaction pathway.
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CE Berryman et al have found that almonds have a consistent LDL- cholesterol lowering effect in healthy individuals and in individuals with high cholesterol and diabetes, in the controlled and free – living settings. Almonds are low in saturated fatty acids and rich in unsaturated fatty acids and contain fiber, phytosterols, plant protein, α-tocopherol, arginine, magnesium, copper, manganese, calcium and potassium. The mechanism which is responsible for the LDL-cholesterol reduction which is observed with almond consumption is likely to be associated with the nutrients which are provided by the almonds, i.e., decreased absorption of cholesterol and bile acid, increased bile acid and cholesterol excretion and an increased LDL-cholesterol receptor activity. The nutrients which are present in almonds regulate the enzymes which are involved in cholesterol synthesis and bile acid production .
The fact that the ^^(V/K) values are the same for the protio and deuterio substrates supports the notion that elimination occurs via a concerted mechanism. However the lack of a substantial observed ^^(V/K) effect , in the presence of a very large deuterium isotope effect, does not support this hypothesis. C-N bond cleavage seems not to be kinetically significant, whilst C-H bond cleavage is. It is therefore unlikely that both bond cleavages occur in the same step. This result can be rationalized by considering the differences between this substrate and the natural one. With the natural substrate C-H and C-N bond cleavage occur concertedly and fast. The chemical reaction occurs faster than the binding / debinding steps, as evidenced by the relatively small deuterium isotope effects obtained for both V and V/K, compared to those obtained with the L-erythro- substrate. With the latter substrate C-H bond cleavage is completely rate limiting. This would be expected as the C-H bond in the L-erythro- substrate is not positioned favourably for removal of the proton. However the amino acid portion remains the same in both substrates and so presumably both substrates experience the same binding interactions at this end of the molecule. In the reaction with the L-erythro- substrate, the hydrogen must be removed with difficulty from C-3, in a slow step, thus giving a large deuterium isotope effect. However once C-H bond cleavage has occurred, C-N bond cleavage could occur quickly. The enzyme is optimized to catalysis the latter cleavage, but is struggling with the first. Thus any isotope effect on C-N bond cleavage would be masked by the large isotope effect on C-H bond cleavage.
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Red shift in emission spectra of four studied hydroxy- cinnamic acids (o-coumaric, sinapic, chlorogenic, and rosmarinic acid), which indicated that binding of these compounds to BSA was associated with changes in the dielectric environment of at least one of its two indole rings, was observed. Only slight blue shift and no shift were noticed during interaction of cinnamic acid with BSA and HSA, respectively [1,2]. It can be expected that changes found in emission spectra of HCA-BSA systems were connected with alterations in microenvironment of Trp-134 because Trp-212 in BSA molecule is in the similar position as Trp-214, where cinnamic acid caused no spectral shift of its emission band. Increasing number of hydroxyl groups in the molecule of HCA was accom- panied by decline of hydrophobicity around Trp. The significant changes in BSA emission spectrum were ob- served after its interaction with chlorogenic or rosma- rinic acid. Other authors described red shifts by 3 to 18 nm in HSA spectrum upon reaction with p-coumaric, ferulic, sinapic, and chlorogenic acid [2,3,25] but the concentrations applied in these experiments were higher (up to 150 µM) than those used in presented work.
Physical and chemical characterization of M. ferrea L. seed oil The yield (%) was calculated from the weight of powder taken for extraction and the weight of the oil obtained (Nkafamiya et al., 2010). Sudan IV test and translucence Lipid Test was performed to confirm that the extracted material was a lipid. The specific gravity of the extracted oil was determined at room temperature with a Pycnometer. The density of the extracted oil was also calculated using the pycnometer data. The moisture content (%)of the oil was determined by drying the oil at 80 °C in a hot air oven until it achieved a constant weight. The acid value, saponification value, un-saponification matter in the oil, peroxide value, iodine value was determined by the standard methods (Hilditch 1946; de Peña et al., 1992; Nzikou et al., 2010; Mahale and Goswami-Giri 2011). The amount of vitamin E and cholesterol was also determined by standard methods (Rutkowski and Grzegorczyk 2007; Daksha et al., 2010). The chemical stability of the oil was checked after 6 months of storage at room temperature.
Table 1 shows the amounts of oleic acid which were added to 1.25 g of palmitic acid, freezing temperatures (the temperatures which two-phase is appeared and the mixture be milky) and the mole fractions of palmitic acid. Figs. 2 and 4 indicate the temperature versus mole fraction of palmitic acid for oleic acid- palmitic acid and palmitic acid- pentadecanoic acid, respectively. Figs. 3 shows the natural log of the mole fraction of palmitic acid versus reverse absolute temperature for oleic acid- palmitic acid system.
Abstract: The effect of temperature on natural antioxidant changes in fresh and dried celery was studied. Celery herbs were dried at 50 and 90ᵒC using a laboratory scale hot air dryer. Fifteen phenolic components (gallic acid, protocatechuic acid, catechol , chlorogenic acid, syringic acid, caffeine , p-coumaric acid, ferulic acid, salycilic acid, cinnamic acid, chrysin, pyrogallol, ellagic acid , catechin and caffeic acid), five flavonoids components were identified in celery herbs (apignen, hesperitin, luteolin, quercetrin and rosmarinic) and three isoflavones components were identified in celery herbs (daidzein, genistein and isorhamnetin) were identified in celery herbs at 50 and 90 ᵒ C. The chemical constituents of apium graveolens volatile oil were determined, the results observed that eleven components were isolated from apium graveolens essential oil and classified into five chemical categories namely, monocyclic terpenes (78.24%), bicyclic terpenes (14.88%), aliphatic hydrocarbons (1.79%), ketones (0.19) and sesquiterpene (2.89%). These identified compounds accounted for 97.99 % of the composition of apium graveolens essential oil. Organoleptic evaluation of Apium graveolens represented the mean scores and their statistical analysis indication for color, aroma, taste, texture and overall acceptability for biscuit treatments mixed with different concentrations of dried Apium graveolens at 50°C and 90°C.
In this study, for the first time, phenolic contents, antioxidant and antimicrobial activity of ethanol extract obtained from Macrocybe crassa (EfraMac) have been examined. Profiling of phenolic compounds exposed the abundance of pyrogallol. Other phenolics were present in the order of vanillic acid> cinnamic acid> p-coumaric acid. There were six unidentified compounds of which two might be benzoic acid derivatives and one could be caffeic acid as revealed by UV-absorption maxima. Besides these, EfraMac also contained flavonoid, ascorbic acid, β-carotene and lycopene. The extract was a good scavenger of free radicals, strong chelator of ferrous ion with high ascorbic acid equivalent antioxidant capacity. Furthermore, EfraMac exhibited antimicrobial effect 0
Phenolic compounds of Nepeta nuda subsp. Lydiae leaves were identified by UHPLC-ESI-MS/MS. To the best of our knowledge, phenolic compounds in N. nuda subsp. Lydiae are reported for the first time. Chlorogenic acid, rosmarinic acid and quinic acid, were found to be the most abundant compound in the methanol extract of N. nuda subsp. Lydiae, among the twenty-seven compounds studied by LC–MS/MS. Also, smaller amounts of kaempferol, p-coumaric acid, tr-caffeic acid, apigenin, luteolin and rhamnetin were identified, quantitatively. In conclusion, leaves of N. nuda subsp. Lydiae have high potential of phenolic contents that mainly attributed with biological activities.
non-specific modes of action and safety make them attractive as antibacterial agents for various applications in medicine, agriculture and food preservation. This is particularly attractive where the use of conventional antibiotics is undesirable or prohibited. Moreover, the evolution of inducible free fatty-acid resistant phenotypes is less problematic than with conventional antibiotics. Free fatty acids have a longstanding safety record. When combined with antibiotics, these acids might prove useful in the prevention and treatment of several bacterial infections.