Single Degradation Product Research Articles

Towards Reducing Food Wastage: Analysis of Degradation Products Formed during Meat Spoilage under Different Conditions.

Foodstuffs, particularly perishable ones such as meat, are frequently discarded once the best-before date has been reached, despite the possibility of their continued suitability for human consumption. The implementation of intelligent packaging has the potential to contribute to a reduction in food wastage by enabling the monitoring of meat freshness during storage time independently of the best-before date. The process of meat spoilage is associated with the formation of specific degradation products, some of which can be potentially utilized as spoilage indicators in intelligent packaging. The aim of the review is to identify degradation products whose concentration correlates with meat shelf life and to evaluate their potential use as spoilage indicators in intelligent packaging. To this end, a comprehensive literature research was conducted to identify the factors influencing meat spoilage and the eight key degradation products (carboxylic acids, biogenic amines, total volatile basic nitrogen, aldehydes, alcohols, ketones, sulfur compounds, and esters) associated with this process. These degradation products were analyzed for their correlation with meat shelf life at different temperatures, atmospheres, and meat types and for their applicability in intelligent packaging. The review provides an overview of these degradation products, comparing their potential to indicate spoilage across different meat types and storage conditions. The findings suggest that while no single degradation product universally indicates spoilage across all meat types and conditions, compounds like carboxylic acids, biogenic amines, and volatile basic nitrogen warrant further investigation. The review elucidates the intricacies inherent in identifying a singular spoilage indicator but underscores the potential of combining specific degradation products to expand the scope of applications in intelligent packaging. Further research (e.g., storage tests in which the concentrations of these substances are specifically examined or research on which indicator substance responds to these degradation products) is recommended to explore these combinations with a view to broadening their applicability.

Identification and Characterization of Forced Degradation Products for Dofetilide using Rapid and Sensitive UPLC-MS/MS Method and HRMS Studies

A simple, rapid and efficient method has been developed and validated using ultra UPLC combined with Q-ToF MS system for recognition and characterization of forced degradation products obtained from dofetilide degradation studies. The dofetilide drug is an antiarrhythmic and belongs to Class III and it was treated with various stress conditions like acidic, basic, oxidative, photolytic and thermal conditions as per ICH guidelines. The main drug shows extensive degradation towards oxidative degradation conditions and single degradation product was identified through chromatogram. The chromatographic separation among main and its impurities were attained through 2.1 × 150, 1.8 μm column from gradient elution using UPLC and its detection at wavelength 230 nm. The validation was performed for the developed method using various parameters like specificity, linearity and robustness studies. Waters Synapt G2 Q TOF system was used and performed MSn studies to establish mass spectral fragmentation pathway for drug and its degradation products and determined accurate masses study. The efficiency of this method was helpful to identify and characterize the drug and degradation products using LC/MSn techniques.

Study of Intrinsic Stability of Mometasone Furoate in Presence of Salicylic Acid by HPTLC and Characterization, Cytotoxicity Testing of Major Degradation Product of Mometasone Furoate

Background: A successful attempt has been done to develop and validate a simple stability indicating HPTLC method for the estimation of Mometasone furoate (MF) and its degradation product in the presence of Salicylic acid (SA). The degradation product was isolated, characterized and tested for cytotoxicity. Introduction: Mometasone furoate (MF) is chemically 9,21-Dichloro-17α-[(2-furanylcarbonyl) oxy]- 11β-hydroxy-16-α-methylpregna-1,4-diene-3,20-dione, a high potency glucocorticoid. Salicylic acid (SA) has antiseptic, antifungal and keratolytic properties. Combination of MF and SA is available in the market as an ointment and is used for the treatment of skin inflammation, skin diseases, acne, skin redness and other conditions. Till now, there is no scientific documentation on HPTLC method for simultaneous estimation of MF and SA in the topical formulation; stress testing of drugs and determination of degradation products. Methods: Combination of Toluene: Ethyl Acetate: Methanol: Ammonia (6.4:1.5:2.0:0.1) was selected as the mobile phase. Detection was done by UV absorbance mode at wavelength 250 nm. Topical formulation containing MF and SA was analyzed by the developed method. The developed method was validated as per ICH guidelines. The standard drugs were subjected to stress testing like hydrolysis, oxidative, thermal and photolytic degradation. Results: Good separation with Rf values 0.61 ± 0.02 (MF) and 0.21 ± 0.02 (SA) was achieved by optimized chromatographic conditions. The % drug content was found to be 97.41±1.15 and 99.43 ± 0.73 for MF and SA, respectively in a topical formulation. From the results of validation parameters, the developed method was found to be specific, accurate, precise, sensitive and robust. After stress testing, SA was found to be stable under different stress conditions. Whereas, MF was found to be base sensitive and single degradation product was observed and isolated by preparative TLC. It was characterized by LC-MS and LC-MS/MS studies. Isolated degradation product was subjected to cytotoxicity testing on A549 and SiHa cell lines. Conclusion: A simple stability indicating HPTLC method was developed and validated for the estimation of MF and its degradation product in presence of SA. Probable structure of degradation product of MF and probable pathway of degradation was interpreted. Results of cytotoxicity testing showed that the degradation product was more cytotoxic as compared to MF against both the cell lines.

Early developmental responses of three sea urchin species to tralopyril and its two degradation products

Tralopyril (TLP) is a newly emerged antifouling biocide which rapidly degrades in water. The scientific data on its possible adverse effects to biota is very limited, and even more limited is the ecotoxicity data of its degradation products (DPs). In the present study we investigated the toxicity of TLP and its two main DPs on fertilization and embryogenesis of three sea urchin species: Clypeaster japonicus, Pseudocentrotus depressus and Hemicentrotus pulcherrimus. The species sensitivity to chemicals was investigated and compared. Additionally, the stability of TLP in test medium was examined.TLP in test medium degraded into one single degradation product. The degradation was slower at 17 °C (average incubation temperature for winter species H. pulcherrimus) than at 20 °C (incubation temperature for the other two species). Both DPs at 100 μg/L did not appear toxic, however, TLP highly affected larval development of all tested species. Sensitivity was similar for C. japonicus and P. depressus, but higher toxicity was noticed for H. pulcherrimus. The increased TLP toxicity on exposed H. pulcherrimus embryos could be attributed to the higher TLP stability at lower incubation temperature. Results suggest higher vulnerability to TLP for species spawning in colder seasons. Fertilization test appeared to be less sensitive than the embryotoxicity test.

STABILITY EVALUATION OF TARTRAZINE BY LIQUID CHROMATOGRAPHY-DIODE ARRAY DETECTOR AND HIGH-RESOLUTION ELECTRON SPRAY IONIZATION QUADRUPOLE TIME-OFFLIGHT MASS SPECTROMETRY/MASS SPECTROMETRY ANALYSIS

Objective: This study investigates the degradation behavior of tartrazine, a synthetic azo dye used in pharmaceutical products.Methods: For this purpose, standard solutions containing E102 were subjected to pH, oxidation, photolytic conditions and were analyzed by the developed high-performance liquid chromatography (HPLC) method.Results: The results show degradation in standard solution with the formation of single degradation product in oxidative visible light condition. The formed unknown degradation product was isolated by semipreparative HPLC and characterized using ultra-HPLC coupled with high resolution tandem mass spectrometer (MS).Conclusion: The isolated component was vacuum dried and subjected to high-resolution MS analysis for the plausible structural elucidation. Based on the fragmentation pattern of one degradation product (ODP) from their MSn studies, the ODP may be identified as 2,5-dihydroxy-1-phenyl-3- (phenyldiazenyl)-2,3-dihydro-1H-pyrazole-4-carboxylic acid.

A Stability-Indicating HPLC-DAD Method for Determination of Stiripentol: Development, Validation, Kinetics, Structure Elucidation and Application to Commercial Dosage Form.

A rapid, simple, sensitive, and accurate isocratic reversed-phase stability-indicating high performance liquid chromatography method has been developed and validated for the determination of stiripentol and its degradation product in its bulk form and pharmaceutical dosage form. Chromatographic separation was achieved on a Symmetry C18 column and quantification was achieved using photodiode array detector (DAD). The method was validated in accordance with the ICH requirements showing specificity, linearity (r 2 = 0.9996, range of 1–25 μg/mL), precision (relative standard deviation lower than 2%), accuracy (mean recovery 100.08 ± 1.73), limits of detection and quantitation (LOD = 0.024 and LOQ = 0.081 μg/mL), and robustness. Stiripentol was subjected to various stress conditions and it has shown marked stability under alkaline hydrolytic stress conditions, thermal, oxidative, and photolytic conditions. Stiripentol degraded only under acidic conditions, forming a single degradation product which was well resolved from the pure drug with significantly different retention time values. This degradation product was characterized by 1H-NMR and 13C-NMR spectroscopy as well as ion trap mass spectrometry. The results demonstrated that the method would have a great value when applied in quality control and stability studies for stiripentol.

Chemical Synthesis of Functional Poly(4-hydroxybutyrate) with Controlled Degradation via Intramolecular Cyclization

We report the synthesis, characterization, and degradation of a new type of functional poly(4-hydroxybutyrate) (P4HB). The polyesters were obtained via the Passerini multicomponent polymerization (MCP) of (E)-4-oxobut-2-enoic acid with two different isocyanides at room temperature and the subsequent hydrogenation. The trans-double bond in the monomer was designed to inhibit the formation of five-membered lactone and promote the polymerization. Two different side groups were incorporated into the side chains of the polyesters by varying the isocyanide component. All the polymers were thoroughly characterized by a variety of methods. Degradation of the polyester under acidic and neutral conditions was investigated by 1H NMR and GPC. In both cases head-to-tail degradation via intramolecular cyclization by the attack of the hydroxyl end group to the ester carbonyl moiety occurred and yielded a nonacidic γ-butyrolactone derivative as the single degradation product. On the basis of control experiments with small model compounds and other types of polyester, we proposed the degradation mechanism. In acidic condition, random scission of the ester group occurred simultaneously at a much slower rate than that of the head-to-tail degradation, while in neutral condition, random scission did not occur and the polymers degraded in a controllable unzipping depolymerization manner.

Chemical and photochemical degradation of chlorantraniliprole and characterization of its transformation products

This study aimed at assessing the photodegradation of the insecticide chlorantraniliprole (CAP) in deionized water and in tap water amended with humic acids and nitrate. Photolysis was carried out under simulated solar or UV-A light. CAP (39μM) photodegradation was slightly faster in tap water than in deionized water with half lives of 4.1 and 5.1days, respectively. Photodegradation rate of CAP was hardly affected by humic acids (up to 100mgL−1) and nitrate. Photodegradation pattern was different in slightly acidic (pH=6.1) deionized water compared to basic (pH=8.0) tap water. Four main degradation products have been isolated and characterized spectroscopically, and crystal structure was recorded for the first two photodegradation products. CAP also degraded in the dark controls, but only at basic pH (23% loss at pH8.0 in tap water after 6days), resulting in the formation of one single degradation product. Our study shows that the degradation of chlorantraniliprole in water is a combination of chemical and photochemical reactions, which are highly dependent on the pH of the solution.

Identification and characterization of a photolytic degradation product of telmisartan using LC–MS/TOF, LC–MS n, LC–NMR and on-line H/D exchange mass studies

Telmisartan, an anti-hypertensive drug, was subjected to stress studies under ICH prescribed conditions of hydrolysis (acidic, neutral and basic), photolysis, oxidation and thermal stress. The drug showed labiality under only photo-acidic condition by forming a single degradation product. HPLC separation of the drug and the degradation product was achieved on C-8 column using gradient method. To characterize the product, a complete mass fragmentation pathway of the drug was initially established. Subsequently, the degradation product peak was subjected to LC–MS/TOF and on-line H/D exchange mass studies. Based on these studies, a tentative structure was assigned to the product as 3-((1,7′-dimethyl-2′-propyl-1H,3′H-2,5′-bibenzo[d]imidazol-3′-yl)methyl)-6H-benzo[c]chromen-6-one, which was verified through 1H LC–NMR experiments.

Time Course of Degradation of Cardiac Troponin I in Patients With Acute ST-Elevation Myocardial Infarction

Although measurement of troponin is widely used for diagnosing acute myocardial infarction (AMI), its diagnostic potential may be increased by a more complete characterization of its molecular appearance and degradation in the blood. The aim of this study was to define the time course of cardiac troponin I (cTnI) degradation in patients with acute ST-elevation myocardial infarction (STEMI). In the ASSENT-2 substudy, 26 males hospitalized with STEMI were randomized to 2 different thrombolytic drugs within 6 hours after onset of symptoms. Blood samples were obtained just before initiation of thrombolysis and at 30 minutes intervals (7 samples per patient). Western blot analysis was performed using anti-cTnI antibodies and compared with serum concentrations of cTnI. All patients exceeded the cTnI cutoff for AMI during the sampling period; at initiation of therapy, 23 had elevated cTnI values. All patients demonstrated 2 bands on immunoblot: intact cTnI and a single degradation product as early as 90 minutes after onset of symptoms. On subsequent samples, 15 of 26 patients showed multiple degradation products with up to 7 degradation bands. The appearance of fragments was correlated with higher levels of cTnI (P<0.001) and time to initiation of treatment (P=0.058). This study defines for the first time the initial time course of cTnI degradation in STEMI. Intact cTnI and a single degradation product were detectable on immunoblot as early as 90 minutes after onset of symptoms with further degradation after 165 minutes. Infarct size and time to initiation of treatment was the major determinant for degradation.

Aerobic biodegradation of virginiamycin in soil

AbstractAerobic biodegradation of virginiamycin was examined in six different soil types over a 64‐d incubation period. The following test conditions were examined in parallel for each soil type: (1) [14C]virginiamycin at 0.5 mg carbon/50 g soil amended with 9.5 mg carbon as unlabeled glucose/50 g soil; and (2) [14C]glucose at 10 mg carbon/50 g soil was used as the reference chemical. The amounts of 14CO2 and [14C]volatile products released upon biodegradation of [14C]virginiamycin and [14C]glucose were collected over the duration of the study. Three of the six soils were extracted at the end of the study, and the extracts were analyzed by HPLC to examine the fate of the parent drug. A mass balance of the applied activity was also determined for each soil type. Virginiamycin was found to biodegrade in each soil type tested, and the calculated mineralization half‐lives ranged from 87 to 173 days for three of the six soils tested with first‐order rate constants of 0.004 to 0.008 day−1. Despite slow mineralization, extensive breakdown of virginiamycin into a series of minor components aerobically with no single degradation product present at &gt;10% of the initial virginiamycin concentration was observed in the remaining three soils. The mass balance of the applied activity of [14C]virginiamycin was in the range 86 to 101% and that of applied [14C]glucose was 91 to 100%. Based on the results, virginiamycin upon entry into the environment is expected to undergo extensive biotransformation in the presence of soil microorganisms.

Induction and Transfer of Enhanced Biodegradation of the Herbicide Napropamide in Soils

In laboratory incubations, the times to 50% loss (DT50) of a first application of napropamide were approximately 25, 45 and 75 days in soil incubated at 25, 15 and 5°C respectively. When treated for a second time, the DT50 values were 4, 7 and 15 days at the same temperatures, irrespective of the temperature of the first incubation. This indicates that enhanced degradation of napropamide in soil can be both induced and expressed at low temperature. A mixed microbial culture able to degrade the herbicide to a single degradation product, identified by HPLC retention time as naphthoxypropionic acid, was obtained from a soil capable of rapid degradation. Addition of a sub-sample of this mixed culture to a previously untreated soil introduced rapid degrading ability. When small amounts of soil capable of rapid degradation were added to previously untreated soil, in both the laboratory and the field, the degradation rate of napropamide increased compared with that in unamended soils.

Wide distribution of an enzyme that catalyzes the hydrolysis of cyclic ADP-ribose

Cyclic ADP-ribose (cADPR) is a metabolite of NAD + that is as effective as inositol trisphosphate in mobilizing intracellular Ca 2+ stores. Its synthesizing enzyme, ADP-ribosyl cyclase, has been shown to be present in mammalian and invertebrate tissues. In this study we identify another widely-distributed enzyme that can hydrolyze cADPR to ADP-ribose. Incubation of cADPR with brain extracts resulted in progressive decrease in its Ca 2+ mobilizing activity. The degradation of cADPR was catalyzed by a heat-labile protein factor in the brain extracts. Analysis by HPLC indicated a single degradation product was produced in equal molar quantity and that it has identical elution time as ADP-ribose. Proton NMR confirmed that the product was ADP-ribose. The degradation enzyme had a Michaelis constant of 0.16 mM and a broad pH maximum around neutrality. Centrifugation studies of the total brain extracts showed that the degradation activity was membrane-bound. Survey of tissues from various animals established that both the degradation and the synthesizing enzyme of cADPR were widely distributed from mammals to invertebrates. Since the degradation enzyme hydrolyzes an unique linkage between the adenine group and the terminal ribosyl moiety of cADPR, we propose to call it cyclic ADP-ribose hydrolase.

Biodegradation of Rose Bengal by Phanerochaete chrysosporium

Rose Bengal (tetrachloro-tetraiodo-fluorescein) was not able to limit the spreading growth of the ligninolytic fungus, Phanerochaete chrysosporium in the presence of Tween 80, and when added to the 5 d old liquid cultures of this organism it was almost completely degraded in 5 h. Thin layer chromatography analysis showed the formation of a single degradation product.

Behavior of 14C oryzalin in soil and plants

Radiochemical studies of field soil treated with 14C oryzalin (3,5-dinitro- N 4, N 4-dipropylsulfanilamide) indicated that the compound was readily degradable. One year after soil treatment with oryzalin, 45% of the original radioactivity had dissipated, 25% was extractable, and 30% was “soil bound”. The extractable fraction contained oryzalin and several degradation products, some of which were isolated and identified. No single degradation product accounted for more than 3% of the applied oryzalin. The “soil-bound” radioactivity was extractable with hot alkali. No significant radioactive residues were detectable in either seed or forage of soybean and wheat plants. No specific metabolites of oryzalin were identified in soybean plants. Trace amounts of radioactivity found in plant tissue appeared to be associated with the various plant constituents.

Mild Thermal Degradation of Pesticides

AbstractPartial degradation of 12 selected analytical grade pesticides was produced by heating the chemicals at temperatures between 100 and 400C. Each pesticide was modified physically and chemically at a temperature at least 300–450C below its complete combustion temperature. At these relatively low temperatures eight of the original nine solids (zineb, picloram, dieldrin, atrazine, bromacil, carbaryl, DNBP, and 2,4‐D) remained solid, while dicamba was converted to a liquid. The three liquids (DBCP, vernolate, and malathion) were all converted to solids. Eight of the original 12 compounds also yielded gray to brown to black residues upon heating. Infrared spectroscopic analyses indicated that the extent of degradation of the heated pesticides ranged from formation of a single degradation product to production of a mixture of compounds. Most pesticides, however, were degraded through loss of one or two substituents of the molecule by processes such as dehalogenation and decarboxylation.