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PubMed2000

Proteolysis in Manchego-type cheese salted by brine vacuum impregnation.

A new salting procedure based on the brine vacuum impregnation of porous products was tested on Manchego-type cheese and compared with conventional brine immersion. Its effect on cheese proteolysis throughout a 90-d ripening period was determined. Three cheese regions were evaluated (the rind, the middle, and the internal regions). The parameters analyzed were total N, water-soluble N, soluble N in trichloroacetic acid and soluble N in phosphotungstic acid by using the Kjeldahl method, casein profile by urea-PAGE, and peptide profile of the water soluble nitrogen extract by reverse-phase HPLC. Free amino acid formation was monitored with a spectrophotometric method by using a Cd-ninhydrin reagent. Globally, proteolysis was significantly affected by ripening stage (increasing throughout all the maturation period studied) and cheese region (rind showed a proteolysis pattern different from the middle and internal regions). The salting procedure only affected cheese proteolysis in the rind, whereas conventional brine-salted cheeses showed lower proteolysis than vacuum-impregnated cheeses.

Amino Acids↗
PubMed2004

Influence of starter culture ratios and warm room treatment on free fatty acid and amino acid in Swiss cheese.

Quantification of water-soluble volatile free fatty acids (FFA) and free amino acids (FAA) was performed as a ripening index and an indirect measure of flavor development in Swiss-type cheeses. The objective of this research was to assess the effect of warm room treatment (WRT) and usage ratio of starter cultures, Streptococcus thermophilus and Lactobacillus helveticus vs. propionibacteria, on the concentration of FFA and FAA in pilot plant-scale Swiss cheese. A capillary gas chromatograph equipped with a flame ionization detector was used for the analysis of FFA in Swiss cheese. Free amino acids were analyzed by the Cd-ninhydrin method. Starter culture ratios did not affect development of FAA during the cheese ripening. However, duration of WRT had an effect on the concentration of FAA in the Swiss cheese. Free amino acids increased considerably during WRT. A continuous increase in FAA was shown during 70-d ripening time after WRT. The concentrations of C2:0 and C3:0 fatty acids were affected by starter culture ratios after 2-wk WRT, but these differences had mostly disappeared after 3-wk WRT. Similar concentrations of FFA and FAA reported in previous studies were developed in Swiss cheese with a 3-wk WRT and a 0.33:1 ratio of Streptococcus thermophilus and Lactobacillus helveticus to propionibacteria.

Amino Acids↗
PubMed2004

Sources of variation in rates of in vitro ruminal protein degradation.

Rates and extents of ruminal protein degradation for casein, solvent soybean meal (SSBM), expeller soybean meal (ESBM), and alfalfa hay were estimated from net appearance of NH3 and total amino acids in in vitro media containing 1 mM hydrazine and 30 mg/L of chloramphenicol. Protein was added at 0.13 mg of N/mL of medium, and incubations were conducted for 4 to 6 h, usually with hourly sampling. Inocula were obtained from ruminally cannulated donor cows fed diets of grass silage or alfalfa and corn silages plus concentrates. Preincubation or dialysis of inocula was used to suppress background NH3 and total amino acids; however, preincubation yielded more rapid degradation rates for casein and SSBM and was used in subsequent incubations. Preincubation with added vitamins, VFA, hemin, or N did not alter protein degradation. Protein degradation rates estimated for SSBM, ESBM, and alfalfa were not different when computed from total N release or N release in NH3 plus total amino acids, regardless of whether amino acids were quantified using ninhydrin colorimetry or o-phthalaldehyde fluorescence. Accounting for the release of peptide-N also did not affect estimated degradation. However, casein degradation rates were more rapid when using total N release or accounting for peptide-N, indicating significant accumulation of small peptides during its breakdown. Rates also were more rapid with inocula from lactating cows versus nonlactating cows with lower feed intake. Protein degradation rates were different due to time after feeding: casein rate was more rapid, but SSBM and ESBM rates were slower with inocula obtained after feeding. Several characteristics of ruminal inoculum that influenced breakdown of the rapidly degraded protein casein did not appear to have direct effects on degradation of protein in soybean meal.

Amino Acids↗
PubMed1981

Quantitative determination of the free amino acids and their derivatives in the common edible mushroom, Agaricus bisporus.

Nitrogen in the ethanol extract of the fruiting bodies of the common edible mushroom, Agaricus bisporus, accounted for about 60% of the total nitrogen of the fruiting bodies, and about 70% of the ethanol-extractable nitrogen was attributable to the free amino acids and their derivatives. Identification and quantitative determination of the free amino acids and their derivatives contained in this fraction were performed after group separation. Of the 44 ninhydrin-positive compounds detected, alanine, glutamic acid, proline and arginine were the most predominant protein amino acids occurring in the free form, and ornithine, N-(gamma-L-glutamyl)-4-hydroxyaniline and gamma-aminobutyric acid were the most plentiful non-protein amino acids. An analytical method of the aromatic compounds characteristic of the mushroom is also described.

Amino Acids↗
PubMed1984

First evidence for the occurrence of N delta-acetyl-L-ornithine and quantification of the free amino acids in the cultivated mushroom, Pleurotus ostreatus.

The free amino acid profile of the fruiting bodies of Pleurotus ostreatus was studied in detail. The first evidence for the occurrence of N delta-acetyl-L-ornithine in the mushroom was presented, and 33 ninhydrin-positive compounds were determined, besides N delta-acetyl-L-ornithine. Alanine, glutamic acid, valine, glutamine, glycine and leucine were predominant protein amino acids occurring in the free form. As regards the non-protein amino acids, ornithine, gamma-aminobutyric acid, saccharopine, alpha-aminoadipic acid, ethanolamine, cystathionine, and N-(gamma-glutamyl)ethanolamine were mainly detected. The sum of the nitrogen of the three abundant amino acids, alanine, glutamic acid and ornithine, accounted for about 40% of the total nitrogen in the amino acid fraction.

Acetates↗
PubMed1999

Effects of angiotensin I-converting enzyme inhibitor from Ashitaba (Angelica keiskei) on blood pressure of spontaneously hypertensive rats.

The inhibitory activity of angiotensin I-converting enzyme (ACE) was extracted with 80% ethanol from the leaves of Ashitaba (Angelica keiskei). The present ACE inhibitor was fractionated and separated with various chromatographies. The antihypertensive effects of the sample (G fraction) from Ashitaba on spontaneously hypertensive rats (SHR) were observed by long-term administration for 10 wk. Another sample (S fraction) from Ashitaba also had antihypertensive effects after a single intravenous administration to SHR. The sample was further purified by using several chromatographies. The ACE inhibitor fraction was characterized as follows: no significant absorbance, a zwitterion, a water-soluble substance and a positive ninhydrin reaction. According to a mass spectrum analysis, the molecular weight of the ACE inhibitor was determined to be 303 and Na-salt ions of carboxyl groups were detected. The ACE inhibitor from Ashitaba contained in the anti-hypertensive fraction was speculated to be very similar to authentic nicotianamine based on a comparative study of inhibitory activity, mass spectrum analysis and thin-layer chromatographies.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1983

Effect of palmitate or lipid emulsion on nitrogen metabolism during hyperthermic perfusion of rat liver.

Livers of fasted rats were perfused for one hour at 37 degrees or 42 degrees. Endogenous hepatic ureogenesis was increased twofold at 42 degrees and the release of endogenous ninhydrin-reactive amino nitrogen was not changed by hyperthermia. Exogenous amino acids at 10 times the normal plasma concentration stimulated hepatic ureogenesis sevenfold at 37 degrees and over twofold at 42 degrees. Exogenous amino acids stimulated hepatic amino acid uptake at 37 degrees. Uptake of the exogenous amino acids at 42 degrees was about 40% of that observed at 37 degrees. However, exogenous amino acid uptake in the presence of 1 mM palmitate was not altered at 42 degrees. Ureogenesis in the presence of supplemental amino acids and palmitate was significantly reduced at 37 degrees and moderately reduced at 42 degrees, suggesting decreased amino acid catabolism. Ten percent Intralipid, a clinically available lipid emulsion primarily consisting of triglycerides in a physical form similar to chylomicrons at a perfusate concentration of 1 ml/100 ml, did not markedly alter hepatic ureogenesis or amino acid dynamics at 37 degrees or 42 degrees in the presence or absence of amino acids. It is concluded that palmitate blocks the adverse effect of hyperthermia on hepatic amino acid uptake.

Amino Acids↗
PubMed1983

Histochemical analysis of liver cells from short term, aflatoxin-dosed and nondosed Coturnix coturnix japonica. 1. Aflatoxin-sensitive quail.

Although aflatoxicosis in Coturnix coturnix japonica has been described, the histochemical localization of liver chemicals and the occurrence of ingested aflatoxins within blood, feces, and liver have not been described. Six to 8-week-old quail, which were intubated with a carrier with or without .3 mg mixed aflatoxins (AFB1, AFB2, AFG1, AFG2)/kg body weight were sacrificed within .25 to 5 days of intubation. Deparaffinized sections of livers were stained for lipids, nucleic acids, polysaccharides, and proteins. Other livers and excrement were homogenized and filtered homogenates as well as blood partitioned against chloroform. The aqueous phase was treated with pepsin and then partitioned, but the organic phase was analyzed directly. Organic phases of .25 to 5 day blood, feces, and liver lacked aflatoxins. Pepsin digesta of blood from males and females dosed 6 hr appeared to contain aflatoxicol (disappeared by 24 hr) and an unknown fluorescent compound, respectively. Whereas an unidentified fluorescent compound was observed within excrement of males dosed 6 hr, female excrement contained a fluorescent compound with an AFB1 Rf (disappeared by 24 hr). Although the liver of males dosed 6 hr had three fluorescent compounds (Rfs for AFB1 and AFB2a), only one was seen within dosed females. Ultra violet absorption spectra of presumed AFB2a and aflatoxicol failed to yield their reported absorption maxima. Livers from dosed quail exhibited bile duct proliferation, cellular necrosis, vacuolization, congestion, fatty changes and mild hepatitis. Sinusoidal membranes were thickened and contained abundant periodic acid-Schiff's (PAS)-positive substances. Although livers of nondosed quail abounded with regularly shaped and uniformly distributed, Sudan IV-positive droplets, livers of dosed quail accommodated few, irregularly-shaped and positioned droplets. Hepatocyte nuclei and nucleoli of dosed quail displayed marked affinities for the Feulgen reagent and toluidine blue O, respectively. Lobules of dosed quail possessed concentrations of cells in which their entire cytoplasm was PAS positive. Treatment of sections with alpha-amylase reduced staining suggesting the presence of glycogen. Ninhydrin-positive substances were distributed throughout the liver in both DQ and non DQ with no apparent difference in intensities between the two livers. Generally the DQ showed mild hepatitis due to aflatoxicosis and the toxin altered liver histochemistry for the major classes of cellular chemicals.

Aflatoxins↗
PubMed2002

Apoptosis of hepatoma cells SMMC-7721 induced by Ginkgo biloba seed polysaccharide.

AIM: To study the apoptosis of hepatoma cells SMMC-7721 induced by polysaccharide isolated from Ginkgo biloba seed. METHODS: Ginkgo biloba seed polysaccharide (GBSP) was isolated by ethanol fractionation of Ginkgo biloba seed and purified by Sephadex G-200 chromatography. The purity of GBSP was verified by reaction with iodine-potassium iodide and ninhydrin and confirmed by UV spectrophotometer, cellulose acetate membrane electrophoresis and Sepharose 4B gel filtration chromatography. The Scanning Electron Microscope (SEM) and Flow Cytometry (FCM) were used to examine the SMMC-7721 cells with and without GBSP treatment at 500 mg/ml for 36 h. RESULTS: GBSP product obtained was of high purity with the average molecular weight of 1.86 X 10(5). Quantitative analysis of SMMC-7721 cells in vitro with FCM showed that the percentages of G(2)-M cells without and with GBSP treatment were 17.01+/-1.28 % and 11.77+/-1.50% (P<0.05), the debris ratio of the cells were 0.46+/-0.12 % and 0.06+/-0.06 % (P<0.01), and the apoptosis ratio of cells was 3.84+/-0.55 % and 9.13+/-1.48 % (P<0.01) respectively. Following GBSP treatment, microvilli of SMMC-7721 cells appeared thinner and the number of spherical cells increased markedly. Most significantly, the apoptosis bodies were formed on and around the spherical cells treated with GBSP. CONCLUSION: GBSP could potentially induce the apoptosis of SMMC-7721 cells.

Apoptosis↗
PubMed1977

A peptide containing aspartic acid, glutamic acid and serine in calf brain synaptic vesicles.

Free amino acids and other amino compounds in calf brain synaptic vesicles were identified and determined by thin-layer chromatography and ion-exchange chromatography. The vesicles contained ten identified amino acids with glutamic acid, aspartic acid, taurine and gamma-aminobutyric acid in the highest concentrations, and also cysteic acid (or cysteinesulfinic acid), glutamine, alanine, serine, glycine and lysine. The vesicles also contained certain unknown acid-labile, ninhydrin-positive compounds, one of which was a peptide yielding, after acid hydrolysis, about 40% aspartic acid, 30% serine, 15% glutamic acid, 10% glycine and possibly some alanine and lysine. The concentration of the peptide in the vesicles was as high as that of all the other amino compounds together.

Amino Acids↗
PubMed1975

Isolation of galantins I and II, water-soluble basic peptides. Studies on antibiotics from the genus Bacillus. III.

Two water-soluble basic antibiotics named galantins I and II were isolated from a strain resembling Bacillus pulvifaciens. Both antibiotics are peptides containing glycine, alanine, ornithine, lysine and some unknown ninhydrin-positive components. An approximate empirical formula C50 plus and minus H98plus and minus 2O17N16 is indicated for galantin I. These are active against some gram-positive, acid-fast and gram-negative bacteria.

Alanine↗
PubMed1976

Isolation of a new antibiotic, laterosporamine. Studies on antibiotics from the genus Bacillus. XIII.

A new antibiotic, named laterosporamine, was isolated from the culture broth of Bacillus laterosporus 340-19. The antibiotic is active against Gram-positive and Gram-negative bacteria in vitro and in vivo. It is a water-soluble basic substance, positive to ninhydrin, SAKAGUCHI'S and DRAGENDORFF'S reagents. A non-peptidic structure with an approximate empirical formula C17H35N7O4 was suggested.

Animals↗
PubMed1977

Studies on aculeacin. I. Isolation and characterization of aculeacin A.

Aculeacin A, a new antifungal antibiotic was isolated from the mycelial cake of Aspergillus aculeatus M-4214. The antibiotic is a white amorphous powder soluble in lower alcohols and hardly soluble in other organic solvents or water. Aculeacin A gave palmitic acid and five ninhydrin-positive products including theonine, hydroxyproline upon acid hydrolysis. The antibiotic showed a potent activity against molds and yeasts, but exhibited no antibacterial activity. Aculeacin A has relatively low toxicity in mice.

Amino Acids↗
PubMed1980

Malioxamycin, a new antibiotic with spheroplast-forming activity. I. Producing organism, fermentation, isolation and characterization.

Strain No. 15748, identifies as Streptomyces lydicus, produces a new antibiotic malioxamycin. Malioxamycin is a water-soluble, amphoteric antibiotic with low molecular weight, having a valine and a malic acid moieties in its structure. It gave a positive ninhydrin and ferric chloride reactions. Malioxamycin inhibited the growth of some Gram-negative bacteria by acting on peptidoglycan synthesis in the cell wall and produced spheroplasts from those sensitive bacteria.

Anti-Bacterial Agents↗
PubMed1980

Tatumine, a peptide from Bacillus brevis Vm4-572-403.

The mutant 572-403 of Bacillus brevis Vm4 was isolated from N-methyl-N'-nitro-N-nitroso guanidine (nitrosoguanidine)-treated cultures of the parental strain. The mutant produces tatumine and edeine B when grown in a defined medium at 40 degrees C. Tatumine is composed of spermidine, glycine, isoserine, and an unidentified ninhydrin-positive compound; it has a molecular weight of less than 730 d (edeine A). It is soluble in water and isopropanol. Tatumine has no antimicrobial activity but has selective cytotoxicity against cultured cells of sarcoma origin. This activity is not destroyed by heating for 1 hour at 60 degrees C.

Animals↗
PubMed1986

Bagougeramines A and B, new nucleoside antibiotics produced by a strain of Bacillus circulans. II. Physico-chemical properties and structure determination.

Bagougeramines A and B obtained as sulfates were soluble in water and positive to Sakaguchi, chlorine-tolidine and ninhydrin color reactions. Their structures were determined by acid hydrolysis and spectroscopic analysis. Structurally they were closely related to gougerotin and they contained the guanidino-D-alanine instead of the serine residue in gougerotin. Bagougeramine B had the spermidine instead of the 6'-NH2 in structure of bagougeramine A.

Anti-Bacterial Agents↗
PubMed1988

Thrazarine, a new antitumor antibiotic. II. Physico-chemical properties and structure determination.

A new antitumor antibiotic thrazarine was soluble in water and positive to anisaldehyde-sulfuric acid and ninhydrin color reactions. The absolute structure of thrazarine was determined to be O-[3R)-2-diazo-3-hydroxybutyryl)-L-serine by acid hydrolysis, spectroscopic analysis and X-ray crystallographic analysis. Structurally, thrazarine was a new member of azaserine group antibiotics.

Antibiotics, Antineoplastic↗
PubMed1989

Isolation and characterization of hypeptin from Pseudomonas sp.

An antibiotic, named hypeptin, was isolated from the culture broth of a strain of Pseudomonas sp. The antibiotic was extracted with butanol and purified by chromatography on a Sephadex LH-20 column. The antibiotic is basic in nature. The dihydrochloride is soluble in aqueous alcohols and positive to ninhydrin and Sakaguchi's reaction. A molecular formula, C44H71N13O15.2HCl was indicated by microanalysis and secondary ion MS. The IR spectrum and acid hydrolysis indicated it to be a peptide antibiotic. The stereochemistries of the amino acids produced by hydrolysis were clarified by HPLC using a chiral column. The antibiotic is active in vitro against a wide variety of anaerobic bacteria and aerobic Gram-positive bacteria.

Anti-Bacterial Agents↗