High-pressure Liquid Chromatography Research Articles

Protective Effect of Perilla Seed Meal and Perilla Seed Extract against Dextran Sulfate Sodium-Induced Ulcerative Colitis through Suppressing Inflammatory Cytokines in Mice.

An excessive inflammatory response of the gastrointestinal tract is recognized as one of the major contributors to ulcerative colitis (UC). Despite this, effective preventive approaches for UC remain limited. Rosmarinic acid (RA), an enriched fraction from Perilla frutescens, has been shown to exert beneficial effects on disease-related inflammatory disorders. However, RA-enriched perilla seed meal (RAPSM) and perilla seed (RAPS) extracts have not been investigated in dextran sulfate sodium (DSS)-induced UC in mice. RAPSM and RAPS were extracted using the solvent-partitioning method and analyzed with high-pressure liquid chromatography (HPLC). Mice with UC induced using 2.5% DSS for 7 days were pretreated with RAPSM and RAPS (50, 250, 500 mg/kg). Then, the clinical manifestation, colonic histopathology, and serum proinflammatory cytokines were determined. Indeed, DSS-induced UC mice exhibited colonic pathological defects including an impaired colon structure, colon length shortening, and increased serum proinflammatory cytokines. However, RAPSM and RAPS had a protective effect at all doses by attenuating colonic pathology in DSS-induced UC mice, potentially through the suppression of proinflammatory cytokines. Concentrations of 50 mg/kg of RAPSM and RAPS were sufficient to achieve a beneficial effect in UC mice. This suggests that RAPSM and RAPS have a preventive effect against DSS-induced UC, potentially through alleviating inflammatory responses and relieving severe inflammation in the colon.

No Sequestration of Commonly Used Anti-Infectives in the Extracorporeal Membrane Oxygenation (ECMO) Circuit-An Ex Vivo Study.

Patients undergoing extracorporeal membrane oxygenation (ECMO) often require therapy with anti-infective drugs. The pharmacokinetics of these drugs may be altered during ECMO treatment due to pathophysiological changes in the drug metabolism of the critically ill and/or the ECMO therapy itself. This study investigates the latter aspect for commonly used anti-infective drugs in an ex vivo setting. A fully functional ECMO device circulated an albumin-electrolyte solution through the ECMO tubes and oxygenator. The antibiotic agents cefazolin, cefuroxim, cefepime, cefiderocol, linezolid and daptomycin and the antifungal agent anidulafungin were added. Blood samples were taken over a period of four hours and drug concentrations were measured via high-pressure liquid chromatography (HPLC) with UV detection. Subsequently, the study analyzed the time course of anti-infective concentrations. The results showed no significant changes in the concentration of any tested anti-infectives throughout the study period. This ex vivo study demonstrates that the ECMO device itself has no impact on the concentration of commonly used anti-infectives. These findings suggest that ECMO therapy does not contribute to alterations in the concentrations of anti-infective medications in severely ill patients.

Pharmacokinetics of a continuous intravenous infusion of hydromorphone in healthy dogs.

Dosing recommendations for hydromorphone intravenous constant rate infusion (IV CRI) are derived from simulations following IV bolus administration. While this extrapolated dose regimen has been described clinically, pharmacokinetics (PK) of hydromorphone infusions in dogs are not yet described. The study objective was to describe the PK of hydromorphone in healthy dogs receiving an IV bolus followed by an IV CRI for 48 h. A prospective, experimental study was performed involving the administration of hydromorphone (0.1 mg/kg IV bolus then IV CRI 0.01 mg/kg/h over a 48 h period) to 6 healthy Beagle dogs. Blood samples were collected at 16 time points between 0 and 58 h relative to the initial bolus. Plasma hydromorphone concentrations were analyzed by high pressure liquid chromatography with tandem mass spectrometry detection. Pharmacokinetic parameter estimates were obtained with compartmental methods using commercially available software. A two-compartment model with first order elimination was used. At the end of the infusion, median (range) plasma hydromorphone concentrations were 6.8 (5.5-19.6) ng/mL. The median total body clearance was 30.4 (19.8-36.7) mL/min/kg; volume of distribution at steady state was 4.5 (3.2-7.8) L/kg; and terminal elimination half-life was 11.2 (7.6-24.3) h. Hydromorphone (0.1 mg/kg IV bolus then IV CRI of 0.01 mg/kg/h) maintained steady-state plasma concentrations above the minimum human analgesic target in healthy Beagle dogs with minimal side effects. Further studies are needed to determine the effective plasma concentrations of hydromorphone in painful dogs.

Utilization of diamondback puffer (Lagocephalus guentheri) biomass for the production of bioactive oligopeptides and their inflammation suppressing effects invitro

Development of new anti-inflammatory drugs has always been of prime interest due to various side effects exerted by common non-steroidal anti-inflammatory drugs (NSAIDs). Hence, due to the biochemical diversity and efficient anti-inflammatory activities of bioactive peptides from oceanic sources, their demand is increasing. In this study, the common diamondback puffer fish (Lagocephalus guentheri) muscle (PM) and visceral (PV) mass waste was used to produce enzymatic hydrolysates using trypsin, alcalase and papain digestion which were further used to obtain inflammation suppressing peptides. High pressure liquid chromatography (HPLC) analysis showed abundant essential amino acids like arginine, alanine, tyrosine, and glutamic acid in muscle as well as visceral part. The data obtained by the anti-inflammatory assays such as albumin denaturation inhibition and membrane stabilization assay of hydrolysates showed that alcalase 12th hr and 6th hr showed highest activity for PM and PV respectively. Further, out of the fractions obtained through ultrafiltration, 10-3 kDa showed higher anti-inflammatory activity which was subsequently purified with gel filtration chromatography. Moreover, the purified active peaks were analysed using LC-MS/MS to acquire a peptide sequence of MEPLGQG (731 Da) and LLHA (453 Da) for PMpep and PVpep respectively. In vitro studies revealed non-cytotoxic effects of peptide and pro-inflammatory cytokine suppression post LPS-stimulation in RAW264.7 cells. Thus, the puffer fish and other marine waste can be exploited for the isolation of potential nutraceutical and therapeutic compounds.

Quechers Extraction Followed by HPLC Estimation of Steroidal Glycoalkaloids viz, α-Chaconine and α-Solanine in Different Solanaceae Family Vegetable Varieties

Glycoalkaloids are the alkaloid derived chemical constituents naturally produced in various plants species especially Solanaceae family. These chemical constituents protect the plant against predators as well as pathogens. The consumption of high dose of glycoalkaloids was toxic to humans. This study was purposeful to evaluate steroidal glycoalkaloids viz., α-chaconine and α-solanine quantity in different Solanaceae family vegetable varieties. The QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) extraction using acetonitrile as extracting solvent was used for extracting steroidal glycoalkaloids in vegetable samples. In the optimized conditions, the standard chromatogram shows clear resolution of α-chaconine and α-solanine. The analytes were identified at 3.15 min for α-chaconine and 4.88 min for α-solanine. The optimized HPLC (High pressure liquid chromatography) method was validated. The method optimized using acetonitrile and 1.0 mM ammonium acetate buffer at pH 4.2 in 65:45 (v/v) as mobile phase at 0.6 mL/min, μBondapak C18 (10 μm, 4.6x250 mm) column as stationary phase and UV detection is selected at 218 nm. Findings suggest that this method was simple and convenient for the estimation of glycoalkaloids in vegetables. The glycoalkaloids was achieved under the acceptable levels of less than 200 mg/kg as prescribed by USFDA and German Federal Institute for Risk Assessment.

Prevalence and clinical implications of heightened plastic chemical exposure in pediatric patients undergoing cardiopulmonary bypass.

Phthalate chemicals are used to manufacture plastic medical products, including many components of cardiopulmonary bypass (CPB) circuits. We aimed to quantify iatrogenic phthalate exposure in pediatric patients undergoing cardiac surgery and examine the link between phthalate exposure and postoperative outcomes. The study included pediatric patients undergoing (n=122) unique cardiac surgeries at Children's National Hospital. For each patient, a single plasma sample was collected preoperatively and two additional samples were collected postoperatively upon return from the operating room and the morning after surgery. Concentrations of di(2-ethylhexyl) phthalate (DEHP) and its metabolites were quantified using ultra high-pressure liquid chromatography coupled to mass spectrometry. Patients were subdivided into three groups, according to surgical procedure: (1) cardiac surgery not requiring CPB support, (2) cardiac surgery requiring CPB with a crystalloid prime, and (3) cardiac surgery requiring CPB with red blood cells (RBCs) to prime the circuit. Phthalate metabolites were detected in all patients, and postoperative phthalate levels were highest in patients undergoing CPB with an RBC-based prime. Age-matched (<1 year) CPB patients with elevated phthalate exposure were more likely to experience postoperative complications. RBC washing was an effective strategy to reduce phthalate levels in CPB prime. Pediatric cardiac surgery patients are exposed to phthalate chemicals from plastic medical products, and the degree of exposure increases in the context of CPB with an RBC-based prime. Additional studies are warranted to measure the direct effect of phthalates on patient health outcomes and investigate mitigation strategies to reduce exposure.

Unveiling the Antioxidant, Cytotoxic, and Anti-Inflammatory Activities and Chemical Compositional Information of an Invasive Plant: Lycium ferocissimum Miers.

In this study, the antioxidant (DPPH and ABTS radical-scavenging, ferric-reducing, iron (II)-chelating), anti-inflammatory (LPS-induced Raw 264.7 cell line), and cytotoxic activities (Du145 and A549 cell lines) of raw fruit, ripe fruit and leaves of the Lycium ferocissimum species were examined. By using high-pressure liquid chromatography, p-OH benzoic acid, caffeic acid, and rutin were detected in the ethanol and water extracts. For the most active raw fruit ethanol extract, the IC50 in terms of the DPPH-scavenging activity was 0.57 mg/mL, and the ABTS inhibition percentage was 88.73% at a 3 mg/mL concentration. The raw fruit ethanol extract exhibited significant inhibition of viability in the Du145 cell line in the concentration range of 62.5-1000 µg/mL. Additionally, the extract effectively reduced the LPS-induced inflammation parameters (TNF-α, IFN-γ, PGE 2, and NO) at a concentration of 31.25 µg/mL. The biological activities of L. ferocissimum, which have been elucidated for the first time, have yielded promising results.

Continuous evaluation of single-dose moxifloxacin concentrations in brain extracellular fluid, cerebrospinal fluid, and plasma: a novel porcine model.

Knowledge regarding CNS pharmacokinetics of moxifloxacin is limited, with unknown consequences for patients with meningitis caused by bacteria resistant to beta-lactams or caused by TB. (i) To develop a novel porcine model for continuous investigation of moxifloxacin concentrations within brain extracellular fluid (ECF), CSF and plasma using microdialysis, and (ii) to compare these findings to the pharmacokinetic/pharmacodynamic (PK/PD) target against TB. Six female pigs received an intravenous single dose of moxifloxacin (6 mg/kg) similar to the current oral treatment against TB. Subsequently, moxifloxacin concentrations were determined by microdialysis within five compartments: brain ECF (cortical and subcortical) and CSF (ventricular, cisternal and lumbar) for the following 8 hours. Data were compared to simultaneously obtained plasma samples. Chemical analysis was performed by high pressure liquid chromatography with mass spectrometry. The applied PK/PD target was defined as a maximum drug concentration (Cmax):MIC ratio >8. We present a novel porcine model for continuous in vivo CNS pharmacokinetics for moxifloxacin. Cmax and AUC0-8h within brain ECF were significantly lower compared to plasma and lumbar CSF, but insignificantly different compared to ventricular and cisternal CSF. Unbound Cmax:MIC ratio across all investigated compartments ranged from 1.9 to 4.3. A single dose of weight-adjusted moxifloxacin administered intravenously did not achieve adequate target site concentrations within the uninflamed porcine brain ECF and CSF to reach the applied TB CNS target.

Application of high-performance thin layer chromatography mass spectrometry (HPTLC MS) in foodomics authenticity

BackgroundChemometric analysis is also a powerful tool that can be used in the preliminary stages of analytical methods optimization, but is also efficient in data processing. These new approaches may be the key to the analysis of proteins, carbohydrate, sphignolipids, polyphenols in different food components. Although there are challenges in identifying and annotating those compounds due to the limited availability of analytical standards and structural diversity. Scope and approachChromatograms are a useful tool for learning more about the chemical make-up of the food being tested. This information can occasionally be implicit or presented in a subtle way. Therefore, to extract it, chemometric tools and data mining techniques are needed. A chromatogram's fingerprint allows for the possibility of performing both identity and quality testing on food. This viewpoint aims to offer a current assessment of chromatographic fingerprinting technique in the area of food authentication. Additionally, this methodology's limitations, absence from official analytical methods, and future directions are discussed. Novel techniques have been employed in the past few decades, ranging from high-pressure thin liquid chromatography (HPTLC) to mass spectrometry (MS) and other spectroscopic methods. In the last decade research developments, and the application of analytical methods in qualitative and quantitative studies of food components and their adulterants is reviewed in the present work. High-pressure Thin liquid chromatography (HPTLC) is hyphenated with high resolution mass spectrometry is particularly addressed due to its applicability in the targeted/untargeted metabolomic analysis of all food components. Key findings and conclusionsIn the current study, the HPTLC-MS technique was used to examine food components and food adulteration. The HPTLC-MS hyphenated techniques were found to be an extremely helpful method for the detection of food adulterants as well as the various food components, such as protein, carbohydrates, lipids, essential oils, and flavonoids, which were found to be effective as medicinally.

Comparative Studies on Simultaneous Estimation of Metformin, Empagliflozin, Remogliflozin, Glimepride and Gliclazide by using RP-HPLC and Diol Technique

Retaining extremely polar metformin and its combination with other non-polar antidiabetic drugs can be difficult and challenging by using the most common reverse-phase high-performance liquid chromatography (RP-HPLC). The retention time of metformin is comparatively short when separated, utilizing C18-based RPC. Peak fronting and tailing effects are commonly observed with metformin (MET), its combination with highly polar antidiabetic medicines, and early elution with void volume. However, normal phase chromatography may occasionally be rendered ineffective due to the low solubility of polar analytes in organic solvents. Therefore, a different and complementary strategy is required for the separation of such a highly polar drug. A more advantageous platform is mixed-mode chromatography. The use of this newer technique of separations has been increased because of its advantages over C18-based RPC for its efficiency, selectivity, sensitivity, specificity and reproducibility towards simultaneous quantification of selected drugs. In this study, we compared two established chromatographic methods for simultaneous quantification of metformin and other moderately polar antidiabetic medications, including empagliflozin, remogliflozin, glimepride, and gliclazide, both in their pure form and in combination tablet dosage. An isocratic elution based on solvent a 15 mM ammonium acetate-Methanol: acetonitrile (10:90 v/v) was used as the mobile phase in first method, which is reversed-phase HPLC with a Zodiac C18 column and chromatographic separation on a 150 × 4.6 mm acclaimed mix mode HILIC-1 column with a particle size of 5 μm. In accordance with ICH standards, both approaches underwent exhaustive validation for linearity, accuracy, precision, selectivity, and resilience. Metformin, empagliflozin, ramogliflozin, glimepride, and gliclazide have not yet been reported to be separated using any method.

The effect of valproate on the amino acids, monoamines, and kynurenic acid concentrations in brain structures involved in epileptogenesis in the pentylenetetrazol-kindled rats.

The study aimed to assess the influence of a single valproate (VPA) administration on inhibitory and excitatory neurotransmitter concentrations in the brain structures involved in epileptogenesis in pentylenetetrazol (PTZ)-kindled rats. Adult, male Wistar rats were kindled by repeated intraperitoneal (ip) injections of PTZ at a subconvulsive dose (30mg/kg, three times a week). Due to the different times required to kindle the rats (18-22 injections of PTZ), a booster dose of PTZ was administrated 7days after the last rats were kindled. Then rats were divided into two groups: acute administration of VPA (400mg/kg) or saline given ip. The concentration of amino acids, kynurenic acid (KYNA), monoamines, and their metabolites in the prefrontal cortex, hippocampus, amygdala, and striatum was assessed by high-pressure liquid chromatography (HPLC). It was found that a single administration of VPA increased the gamma-aminobutyric acid (GABA), tryptophan (TRP), 5-hydroxyindoleacetic acid (5-HIAA), and KYNA concentrations and decreased aspartate (ASP) levels in PTZ-kindled rats in the prefrontal cortex, hippocampus, amygdala and striatum. Our results indicate that a single administration of VPA in the PTZ-kindled rats restored proper balance between excitatory (decreasing the level of ASP) and inhibitory neurotransmission (increased concentration GABA, KYNA) and affecting serotoninergic neurotransmission in the prefrontal cortex, hippocampus, amygdala, and striatum.

Liquid Chromatography with Tandem Mass Spectrometry Analysis of Carboxymethyl Lysine in Indonesian Foods.

There is little data on directly measured carboxymethyl lysine (CML) content in Indonesian foods. This study aimed to generate a database of CML values in foods commonly consumed in West Java and West Sumatra. The results were to be used to update our previous estimated CML values. CML values in food samples were measured using high-pressure liquid chromatography with tandem mass spectrometry (HPLC-MS/MS). Food protein content was analyzed by Kjeldahl's method or inferred from the nutrition facts' label. A total of 210 food samples were examined, with the food groups of meat and poultry (1.06 mg CML/100 g edible food), and starchy foods (0.21 mg/100 g edible food) having the highest and lowest mean CML levels, respectively. We found that the foods with the top three highest CML content were fried starch dough (cimol), fried fish crackers, and chicken gulai. The mean of the estimated values (0.80 mg CML/100 g edible food) was higher than the directly measured values (0.66 mg CML/100 g edible food), [p < 0.035]. Conclusion: This database provides information on CML values in Indonesian foods, and can be further used to make a guide policy for the selection of foods to reduce non-communicable diseases. Further measurements are needed on Indonesian dishes to complete the database.

Huanglian-banxia promotes gastric motility of diabetic rats by modulating brain-gut neurotransmitters through MAPK signaling pathway.

Gastric motility disorder is an increasingly common problem among people with diabetes. Neurotransmitters have been recognized as critical regulators in the process of gastric motility. Previous study has shown that herb pair huanglian-banxia (HL-BX) can improve gastric motility, but the underlying mechanism is still unclear. The aim of this study was to further investigate the role of HL-BX in modulating brain-gut neurotransmission to promote gastric motility in diabetic rats, and to explore its possible mechanism. The diabetic rats were divided into five groups. Gastric emptying rate, intestinal propulsion rate, body weight, and average food intake were determined. Substance P (SP), 5- hydroxytryptamine (5-HT), and glucagon-like peptide -1 (GLP-1) in the serum were measured by enzyme-linked immunosorbent assay. Dopamine (DA) and norepinephrine (NE) in the brain were analyzed by high-pressure liquid chromatography with a fluorescence detector. Protein expression of the tissues in the stomach and brain was determined by Western blot. HL-BX reduced average food intake significantly, increased body weight, and improved gastric emptying rate and intestinal propulsion rate. HL-BX administration caused a significant increase in SP, GLP-1, and 5-HT, but a significant decrease in DA and NE. Interestingly, HL-BX regulated simultaneously the different expressions of MAPK and its downstream p70S6K/S6 signaling pathway in the stomach and brain. Moreover, berberine exhibited a similar effect to HL-BX. These results indicated that HL-BX promoted gastric motility by regulating brain-gut neurotransmitters through the MAPK signaling pathway. HL-BX and MAPK provide a potential therapeutic option for the treatment of gastroparesis.

Laccase-Mediated Oxidation of Phenolic Compounds from Wine Lees Extract towards the Synthesis of Polymers with Potential Applications in Food Packaging.

Laccase from Trametes versicolor was applied to produce phenolic polymeric compounds with enhanced properties, using a wine lees extract as the phenolic source. The influence of the incubation time on the progress of the enzymatic oxidation and the yield of the formed polymers was examined. The polymerization process and the properties of the polymeric products were evaluated with a variety of techniques, such as high-pressure liquid chromatography (HPLC) and gel permeation chromatography (GPC), Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The enzymatic polymerization reaction resulted in an 82% reduction in the free phenolic compounds of the extract. The polymeric product recovery (up to 25.7%) and the molecular weight of the polymer depended on the incubation time of the reaction. The produced phenolic polymers exhibited high antioxidant activity, depending on the enzymatic oxidation reaction time, with the phenolic polymer formed after one hour of enzymatic reaction exhibiting the highest antioxidant activity (133.75 and 164.77 μg TE mg-1 polymer) towards the ABTS and DPPH free radicals, respectively. The higher thermal stability of the polymeric products compared to the wine lees phenolic extract was confirmed with TGA and DSC analyses. Finally, the formed phenolic polymeric products were incorporated into chitosan films, providing them with increased antioxidant activity without affecting the films' cohesion.

Effect of liposomal complexes of quercetin-rich flavonoids from French Marigold (Tagetes patula L.) on Jurkat cell viability

Background: Natural polyphenols are naturally used in traditional medicine to treat various diseases. Despite their healthful properties, ingesting phenolic compounds in food form does not provide a sufficient concentration for systemic therapeutic effects due to their low solubility in water, poor absorption, and fast metabolism. This problem has been solved by creating various composite pharmaceuticals from phenolic compounds using different methods to stabilize polyphenols. Objective: The purpose of this study was to assess the effects of the DPPA (1,2-palmitoyl phosphatidic acid) and DPPC (dipalmitoyl phosphatidylcholine) liposomes on the protective effects of a quercetin-rich flavonoid fraction extracted from French Marigold (Tagetes patula L.) on the viability of Jurkat cells. The study will examine both intact cells and cells that have been incubated under oxidative stress conditions. Materials and Methods: Quercetin-rich flavonoid fraction was extracted from a French Marigold (Tagetes patula L.) by thin-layer chromatography (TLC), High-pressure liquid chromatography (HPLC), and Liquid Chromatography-Mass Spectrometry (LC-MS) methods. Extract alone and in complex with dipalmitoyl phosphatidylcholine (DPPC) and 1,2- dipalmitoyl phosphatidic acid (DPPA) liposomes were added to the Jurkat cells culture at a rate of 2 mg/mL−1.The 3-(4,5-dimethylthiazol-2)-2,5-diphenyltetrazolium bromide (MTT) test assayed Cell viability by evaluating cellular dehydrogenase activity. Results: Flavonoids were separated and identified in the marigold extracts by TLC, HPLC, and LC-MS methods. The spectrophotometric absorption spectrum of the quercetin-rich flavonoid fraction extracted from French Marigold (Tagetes patula L.) shows two peaks corresponding to benzoyl (254nm) and cinnamyl (375nm) aromatic rings. In the complex of quercetin-rich flavonoid fraction with DPPC and DPPA liposomes, the spectrophotometric absorption peak at 254nm was not detected, while the absorption intensity of the peak at 375nm was sharply reduced. The quercetin-rich flavonoid fraction alone and in combination with DPPC liposome increased intact and incubated under low- and high-intensity oxidative stress conditions Jurkat cells’ viability but did not reveal effect in combination with DPPA liposome. Conclusions: The quercetin-rich flavonoid fraction extracted from French Marigold (Tagetes patula L.) forms stable complexes with DPPC and DPPA liposomes that allow the storage of high content of phenolic compounds in lipid nanocapsules. The use of the liposomal system in the pharmaceutical and food industry allows for carried and controlled bioactive-compound release, which is considered one of the main strategies to improve and enhance the quality of food, providing preventative healthcare for the population and decreasing the risk of disease. Keywords: bioactive-compound, polyphenols, Quercetin, Liposomes, Jurkat cells, therapeutic effects, pharmaceuticals

Development of propolis, hyaluronic acid, and vitamin K nano-emulsion for the treatment of second-degree burns in albino rats

Burns are the fourth most common type of injury worldwide. Many patients also suffer numerous infections and complications that impair the burn healing process, which makes the treatment of burns a challenge. This study aimed to prepare and characterize nano-emulsion (NE) of propolis, hyaluronic acid, and vitamin K for treatment of second-degree burns. High-Pressure Liquid Chromatography (HPLC) was used for the qualitative assessment of the phenolic and flavonoid contents in crude propolis. The structural, optical, and morphological characterization, besides the antimicrobial, antioxidant, cytotoxicity, in-vitro, and in-vivo wound healing activities were evaluated. For in-vivo study, 30 adult male albino rats were divided randomly into control and treated groups, which were treated with normal saline (0.9%), and NE, respectively. The wounds were examined clinicopathologically on the 3rd, 7th, and 14th days. The NE revealed the formation of a mesh-like structure with a size range of 80–180 nm and a 21.6 ± 6.22 mV zeta potential. The IC50 of NE was 22.29 μg/ml. Also, the NE showed antioxidant and antimicrobial activity against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. The in-vitro investigation of the NE on normal human skin fibroblasts using scratch assay proved an acceleration for wound healing. The treated rats showed improved wound healing clinically and pathologically and wound contraction percent (WC %) was 98.13% at 14th day, also increased epithelization, fibrous tissue formation, collagen deposition, and angiogenesis compared to the control. It could be concluded that the prepared NE possesses antimicrobial, antioxidant, and healing effect in the treatment of second-degree burns.

Dissipation of pendimethalin in a water‐seeded rice field and implications for water management

AbstractWater‐seeded rice (Oryza sativa L.) in California is produced near growing urban centers and a variety of neighboring high‐value crops, which make water quality a paramount concern because of potential herbicide residue contamination in downstream surface waters. Pendimethalin is a potential herbicide for use in California water‐seeded rice. A study was conducted to characterize pendimethalin's dissipation in water of a water‐seeded rice field. A capsule suspension (CS), emulsifiable concentrate (EC), and granule (GR) pendimethalin were applied onto flooded rice plots at 1.1, 2.3, and 3.4 kg ai ha−1 rates. Water samples were collected periodically and analyzed with an high pressure liquid chromatography tandem mass spectrometry system for residues. Pendimethalin dissipation differed across formulations. The initial sampled concentrations recorded values from 3.0 to 125.6 parts per billion (ppb). First‐order dissipation resulted in half‐lives for the CS from 2.3 to 3.5 days, the EC from 0.6 to 0.7 days, and the GR from 3.5 to 6.9 days. Pendimethalin use in water‐seeded rice is at low risk of contaminating downstream surface waters; however, early sampled residue concentrations could be concerning. The results can assist in generating management tactics like water‐holding periods to avoid potential downstream off‐target effects and ensure herbicidal activity in the applied area after a pendimethalin application in a water‐seeded rice field.

Characterization, production optimization and ecotoxicity of a lipopeptide biosurfactant by Pseudomonas citronellolis using oily wastewater

Considering both fundamental principles and application perspectives, it is imperative to characterize biosurfactants (BSFs) for replacing their synthetic counterparts. In this study, a BSF produced by the Pseudomonas citronellolis 620 C bacterium, using oily wastewater, was identified as a lipopeptide based on ultraviolet spectroscopy, thin layer chromatography, high-pressure liquid chromatography and nuclear magnetic resonance spectroscopy. The latter detected the lactone ring at the 5.1–4.9 ppm region, suggesting it as a cyclic lipopeptide (CLP). Gas chromatography/mass spectrometry detected high percentage of C16:0, C18:0 fatty acids, and aliphatic amino acids. A novel CLP is here proposed. To reduce its bioprocess costs, different nitrogen (N)-sources were tested using oily wastewater as the main nutrient source. Ammonium sulfate was the best N-source for the bacterium, reaching BSF production of 556 mg/L, at 10/2 C/N ratio. The BSF ecotoxicity for Aliivibrio fischeri, expressed as effective concentration (EC), was 0.45 and 3.04 g/L as EC20 and EC50, respectively. For Daphnia magna, the EC50 at 24 h and 48 h were 0.980 and 0.936 g/L, respectively. The lipopetide had no estrogenic activity up to 8 g/L. These data make the novel lipopeptide suitable for agriculture, environmental restoration, as dispersant in waste(water) biodisposal and life sciences applications.

Scaling the Process Chemistry of a COVID-19 Antiviral Pharmaceutical Down for a Multistep Synthesis Experiment in the Undergraduate Teaching Laboratory.

Molnupiravir is an orally bioavailable direct acting antiviral agent that received emergency use authorization in late 2021 from the FDA for the treatment of patients with mild, moderate, or severe COVID-19. This prodrug is metabolized into a ribonucleoside that is incorporated into the viral RNA during replication. Its tautomerization between cytidine- and uridine-like forms ultimately causes multiple irreversible errors in the genetic code of the virus, which prevents successful viral replication. There are multiple process chemistry routes for molnupiravir synthesis published in the literature that attempt to maximize synthetic yield while minimizing cost and waste, which are goals similar to those of an implementable educational laboratory experiment for the teaching laboratory. We have developed a multiweek laboratory module for undergraduate students in which students conduct a multistep synthesis of molnupiravir. Specifically, our Organic Chemistry II Laboratory students performed the final two steps of molnupiravir synthesis using procedures derived directly from the published process chemistry literature. We utilized this opportunity to introduce students to reading and interpreting these primary experimental sources. Students obtained authentic characterization data via high pressure liquid chromatography (HPLC) and nuclear magnetic resonance (NMR) spectroscopy to assess the conversion and purity of their products at each synthetic step. We report our in-lab activities and student generated data as well as suggestions for how this laboratory experiment could be tailored to meet similar learning objectives in other courses, such as medicinal chemistry or capstone laboratory courses, and as a function of available instrumentation.

Biosurfactants—An Overview

AbstractThe large structural and functional variety of bio‐surfactants (BS), which are produced by microorganisms, leads to the use of several methods to study these amphiphilic molecules. This review seeks to consolidate information on various surface‐active product extraction techniques, microbiological screening methodologies, and analytical terminologies utilized in this sector. The potential benefits and drawbacks of various approaches for studying cell biomass or microbial culture broth for the generation of surface‐reactive chemicals are also discussed. Additionally, the most popular techniques for detection, structural characterization, and purification of a variety of BS are introduced. A number of straightforward techniques are described in detail, including dialysis, ion exchange, solvent extraction, ultrafiltration, lyophilization, and thin layer chromatography (TLC). In addition to more sophisticated techniques like nuclear magnetic resonance (NMR), fast atom bombardment mass spectroscopy (FAB‐MS), gas chromatography‐mass spectroscopy (GC‐MS), high‐pressure liquid chromatography (HPLC), and infrared (IR), proteolysis and sequencing of amino acid are also explained. In this field of study, it is quite necessary to combine several analytical techniques, and it often takes multiple iterations to purify, isolate, and characterize different surface‐active substances. The numerous approaches that are essential for researching bio‐surfactants are covered in this review.