Evaluation of crude oil biodegradation using mixed fungal cultures.

The use of potent fungal mixed cultures is a promising technique for the biodegradation of crude oil. Four isolates of fungi, namely, Alternaria alternata (AA-1), Aspergillus flavus (AF-3), Aspergillus terreus (AT-7), and Trichoderma harzianum (TH-5), were isolated from date palm soil in Saudi Arabia. The mixed fungal of the four isolates have a powerful tool for biodegradation up to 73.6% of crude oil (1%, w/v) in 14 days. The fungal consortium no. 15 containing the four isolates (1:1:1:1) performed significantly better as a biodegradation agent than other consortium in a variety of environmental factors containing crude oil concentration, incubation temperature, initial pH, biodegradation time and the salinity of the medium. The fungal consortium showed better performance in the biodegradation of normal alkanes (n-alkanes) than that of the polycyclic aromatic hydrocarbons (PAHs); the biodegradation efficiency of normal alkanes of the fungal consortium (67.1%) was clearly high than that of the PAHs (56.8%).

Development and validation of UPLC-MS/MS method for the simultaneous quantification of anaplastic lymphoma kinase inhibitors, alectinib, ceritinib, and crizotinib in Wistar rat plasma with application to bromelain-induced pharmacokinetic interaction.

Bromelain, the aqueous extract of pineapple, has been used as a food supplement with reported nutritional and therapeutic benefits. Bromelain has anti-cancer, anti-inflammatory, antithrombotic, and fibrinolytic effects. Anaplastic lymphoma kinase (ALK) inhibitors, including alectinib (ALC), ceritinib (CER), and crizotinib (CRZ), have been efficiently used in the management of non-small cell lung cancer (NSCLC). The solubility of ALC, CER, and CRZ is much higher at low acidic pH (pH 1) and it decreases as the pH increases affecting their absorption with a subsequent decrease in their bioavailability. It was thought that the intake of bromelain could result in a decrease in the bioavailability of ALC, CER, and CRZ due to bromelain-induced alkalizing effect following digestion. On the contrary, bromelain could possibly increase plasma exposure of the cited drugs due to its known muco-permeation enhancing effect. The therapeutic-anticancer effect of bromelain can be possibly increased/enhanced with concomitant intake of other anticancer medications or it can add to the value of food supplements for its known nutritional benefits. Thus, this work aims at studying the possibility of any PK interaction when bromelain was taken while on ALC/CER/CRZ therapy. In this work, a new UPLC-MS/MS method was developed and validated for the simultaneous determination of ALC, CER, and CRZ in rat plasma. Further application of the proposed method was performed to test the possibility of the PK interaction between bromelain and the selected ALK inhibitors in Wistar rats. Simple protein precipitation with acetonitrile was used for sample preparation. Chromatographic analysis was performed on Waters BEH™ C18 column with a mixture of acetonitrile/water containing 0.1 % formic acid (70: 30, v/v) as the mobile phase. The method permitted the analysis of ALC, CER, and CRZ in concentration ranges of 2-200, 0.4-200, and 4.0-200 ng/mL, respectively. Bromelain administration caused a significant decrease in plasma levels of CER and CRZ with lowered Cmax, AUC0-t and AUC0-∞, along with an increase in the apparent clearance. However, no significant effect was noticed with ALC. Thus, attention should be paid to avoid the intake of bromelain with CER or CRZ.

Molecular profile of aflatoxigenic and non-aflatoxigenic isolates of Aspergillus flavus isolated from stored maize.

Maize is a significant staple crop and utilized in Saudi Arabia as food and feed, but maize is often infected with Aspergillus flavus in tropical and subtropical climates, especially during storage. This study intended at a polyphasic approach, consisting of microscopic morphological, biochemical, and molecular characterizations that were applied to 29 of A. flavus isolates of stored maize, with the goal of characterization and identification of aflatoxigenic and non-aflatoxigenic A. flavus isolates. The technique of real-time PCR (RTi-PCR) was used to detection of A. flavus in stored maize samples, the findings have been very accurate. Centered on macroscopic morphological (primarily colony color and morphology of conidia) and microscopic (morphology of conidia and size) characteristics. Results have shown 23 A. flavus isolates (80%) were categorized as the dark green of colonies also all isolates were rough conidia. The isolates have been two different groups, 16 isolates (62%) had sclerotium-forming and the remaining 13 isolates (38%) had no sclerotium-forming isolates. To the identification of aflatoxigenic isolates of A. flavus in stored maize, we utilized the qualitative methods (easy and inexpensive) like UV test, yellow pigmentation, and ammonia vapor and quantitative method as HPLC (accurate and expensive). the accuracy methods to the identification aflatoxigenicity isolates, vary, and classified in the following descending order: HPLC (100%) > UV method (81%) > yellow pigmentation (YP) and ammonia vapor (AV) (63%). The profile of Aflatoxigenicity of A. flavus isolates by HPLC has been involved in two types first of 11 isolates (38%) have been aflatoxigenic isolates while 18 isolates (62%) were non-aflatoxigenic isolates. The expression of six aflatoxins (AFs) genes (aflD, aflM, aflO, aflP, aflR, and aflQ) was estimated using PCR and RT-PCR. PCR of all genes did not correspond to the aflatoxigenic isolates. The transcriptional analysis of aflO and aflQ was a beneficial marker for discriminating aflatoxigenic from non-aflatoxigenic A. flavus isolates. Also, qRT-PCR indicated that non-aflatoxigenic isolates had a high incidence of defect or downregulation in late AF-genes contrast with early AF-genes. therefore, these non-aflatoxigenic isolates could be critical factors for an efficient and competent strategy for the control of aflatoxin contamination pre-harvest can be considered.

Silver nanoparticles biosynthesis using Saussurea costus root aqueous extract and catalytic degradation efficacy of safranin dye.

Nanobiotechnology is a fast growing field in which instruments are created by nano size particles of approximately 1 to 100 nm (1 to 100 nm) of the scale of nanometers. Nanoparticles today have potential implications for life sciences and human health applications. In this research, silver nanoparticles (AgNPs) were successfully synthesized using Saussurea costus root aqueous extract and AgNPs have been characterized by the use of UV-Vis, Scanning Electron Microscopes (SEM), and Electromicroscopy of transmission (TEM) and Energy Dispersive X-ray Spectroscopy (EDXs). The highest number of particles are in the 5 to 15 nm range. AgNPs have been added in saffron dye solution for degradation dye biosynthesizing, and product analysis using UV/vision spectrophotometer, FTIR and HPLC has been performed. Green-summed AgNPs effectively degraded the color, with UV/VIS spectrophotometers, around 84.6 percent at 72 h of exposure time. The decrease in tested dye and presence of multiple new highs in the samples treated with different retention times (Rt) 2.30, 6.10 and 12.24 min, is positive for the biodegradation compared to the untreated dye with single high at 10.31 min, respectively. This green chemistry is very advantageous for AgNPs biosynthesis, for example, cost-effectiveness and usability for medicinal, pharmaceutical and extensive industrial applications. Furthermore, the bio-recovery unit for plant extracts provides a greater ease of handling, compared to micro-organisms.

Flavoured water consumption alters pharmacokinetic parameters and increases exposure of erlotinib and gefitinib in a preclinical study using Wistar rats.

BACKGROUND: Erlotinib (ERL) and Gefitinib (GEF) are considered first line therapy for the management of non-small cell lung carcinoma (NSCLC). Like other tyrosine kinase inhibitors (TKIs), ERL and GEF are mainly metabolized by the cytochrome P450 (CYP450) CYP3A4 isoform and are substrates for transporter proteins with marked inter-/intra-individual pharmacokinetic (PK) variability. Therefore, ERL and GEF are candidates for drug-drug and food-drug interactions with a consequent effect on drug exposure and/or drug-related toxicities. In recent years, the consumption of flavoured water (FW) has gained in popularity. Among multiple ingredients, fruit extracts, which might constitute bioactive flavonoids, can possess an inhibitory effect on the CYP450 enzymes or transporter proteins. Therefore, in this study we investigated the effects of different types of FW on the PK parameters of ERL and GEF in Wistar rats. METHODS: ERL and GEF PK parameters in different groups of rats after four weeks consumption of different flavours of FW, namely berry, peach, lime, and pineapple, were determined from plasma drug concentrations using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). RESULTS: Data indicated that tested FWs altered the PK parameters of both ERL and GEF differently. Lime water had the highest impact on most of ERL and GEF PK parameters, with a significant increase in Cmax (95% for ERL, 58% for GEF), AUC0-48 (111% for ERL, 203% for GEF), and AUC0-∞ (200% for ERL, 203% for GEF), along with a significant decrease in the apparent oral clearance of both drugs (65% for ERL, 67% for GEF). The order by which FW affected the PK parameters for ERL and GEF was as follows: lime > pineapple > berry > peach. CONCLUSION: The present study indicates that drinking FW could be of significance in rats receiving ERL or GEF. Our results indicate that the alteration in PKs was mostly recorded with lime, resulting in an enhanced bioavailability, and reduced apparent oral clearance of the drugs. Peach FW had a minimum effect on the PK parameters of ERL and no significant effect on GEF PKs. Accordingly, it might be of clinical importance to evaluate the PK parameters of ERL and GEF in human subjects who consume FW while receiving therapy.

Development and validation of UPLC-MS/MS method for studying the pharmacokinetic interaction of dasabuvir and tamoxifen, 4-hydroxytamoxifen in Wistar rats.

Hepatitis C virus (HCV) is the main cause of chronic hepatitis and probably liver cirrhosis. Dasabuvir (DSV) is a direct-acting antiviral agent with efficiency in managing HCV. The anti-viral activity of the anti-estrogen drug tamoxifen (TAM) suggested the synergistic effect of DSV and TAM for blocking the replication of HCV. However, being substrates and inhibitors of efflux transporters (TAM inhibits P-gp, DSV inhibits P-gp and BCRP), there is a possibility for a pharmacokinetic (PK) drug-drug interaction. In this work, a new UPLC-MS/MS method was developed and validated for the simultaneous determination of TAM, its active metabolite 4-hydroxy tamoxifen (TOH), and DSV in rat plasma. The method was applied to investigate the PK interaction between DSV and TAM/TOH following the co-administration of DSV and TAM to Wistar rats. Chromatographic analysis was performed on Waters BEHTM C18 column using a mobile phase of acetonitrile/water containing 0.1% formic acid (80: 20, v/v). The method allowed the determination of concentration ranges 20-1000, 0.1-500, 0.5-500 ng/mL for DSV, TAM, and TOH, respectively. Unexpectedly, results revealed the absence of PK interactions between DSV and TAM/TOH, compared with their single administration, suggesting the safety of co-administering DSV/TAM as an anti-viral combination without the need of dosage adjustment.

A Pharmacokinetic Interaction Study of Sorafenib and Iced Teas in Rats Using UPLC-MS/MS: An Illustration of Beverage-Drug Interaction.

Iced teas (ITs), also known as ready-to-drink teas, have gained much popularity among many nations. The modulatory effect of tea beverages on CYP3A4 increases the possibility of their potential interactions with many coadministered medications. Being a substrate of CYP3A4, sorafenib (SOR), the first-line therapy for the treatment of hepatocellular carcinoma, shows a great probability to exhibit pharmacokinetic (PK) interaction with ITs. For this purpose, different groups of Wistar rats were given oral doses of SOR (40 mg/kg), along with different types of ITs. The concentration of SOR in rat plasma was determined using UPLC-MS/MS. Chromatographic analysis was performed on a C18 analytical column, Acquity UPLC BEH™ (100 × 1.0 mm, i.d., 1.7 µm particle size), using erlotinib (ERL) as an internal standard. Isocratic elution was performed with a mobile phase consisting of two solvents: solvent A (water with 0.1% formic acid) and solvent B (acetonitrile with 0.1% formic acid), in a ratio of 30 : 70, v/v, respectively. Quantitation was performed using MRM of the transitions from protonated precursor ions [M+H]+ to product ions at m/z 465.12 > 252.02 (SOR) and m/z 394.29 > 278.19 (ERL). The method was fully validated as per the FDA guidance for bioanalytical method validation in the concentration range of 2.5-500 ng/mL. Different PK parameters were calculated for SOR in all rat groups and groups administered with ITs and SOR, compared with groups with simply water and SOR. Experimental data revealed that ITs caused a general reduction in SOR bioavailability; an approximate reduction of 30% was recorded for all types of tested ITs. These data indicate that ITs could affect the PK profile of SOR in rats.

UPLC-MS/MS study of the effect of dandelion root extract on the plasma levels of the selected irreversible tyrosine kinase inhibitors dasatinib, imatinib and nilotinib in rats: Potential risk of pharmacokinetic interactions.

Tyrosine kinase inhibitor treatments for chronic myeloid leukaemia based on nilotinib (NIL), dasatinib (DAS) and imatinib (IMA) have improved patient quality of life and have turned chronic myeloid leukemia from a fatal disease into a chronic disease. Dandelion is a rich source of phenolic compounds with strong biological properties, and the effects of using this plant in the treatment of different illnesses can be linked to the presence of various polyphenols found in the different parts of the plant. Thus, dandelion can potentially be used as a nutraceutical (dietary antioxidant) to prevent different disorders associated with oxidative stress, i.e. cardiovascular disorders, cancer and inflammatory processes. Mutual interference between a drug and a food constituent may result in altered pharmacokinetics of the drug and undesired or even dangerous clinical situations. In the present study, a bioanalytical ultra performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS) method was developed and validated for the quantification of DAS, IMA and NIL in rat plasma. Sample preparation was carried out using solid-phase extraction with C18 cartridges with a good extraction recovery of ≥94.37% for the three drugs. The method was fully validated as per the US Food and Drug Administration guidelines.

Ultra-performance LC-MS/MS study of the pharmacokinetic interaction of imatinib with selected vitamin preparations in rats.

AIM: The growing interest of cancerous patients in using vitamins, while on imatinib (IMA) therapy, increased the risk of their pharmacokinetic interactions. METHODOLOGY: Ultra-performance LC-MS/MS method was developed and validated for the determination of IMA following oral administration of selected vitamin preparations (vitamin A, E, D3 and C) in rat plasma using a hybrid sample preparation technique of protein precipitation followed by SPE. RESULTS: The method showed good linear response for IMA over the concentration range 1-500 ng/ml. Co-administered vitamin preparations could affect IMA pharmacokinetic profiling through either an increase (vitamin A and E) or a decrease (vitamin C) in IMA bioavailability. Vitamin D3 produced no significant effect on IMA bioavailability. CONCLUSION: Particular concern should be paid when vitamin preparations are administered with IMA.

Validated UPLC-MS/MS method for the quantification of dasatinib in plasma: Application to pharmacokinetic interaction studies with nutraceuticals in Wistar rats.

Dasatinib (DAS) is a tyrosine kinase inhibitor (TKI) used in the treatment of chronic myeloid leukemia and in the management of ulcerative colitis (UC). Since some nutraceuticals (e.g. curcumin, olive oil, and cocoa extract) could alter the function of ABC transporters and /or CYP450 enzymes, DAS bioavailability could potentially be affected following their co-administration. This work aims at studying the possibility of PK interaction between DAS and the selected nutraceuticals in UC rats using UPLC- MS/MS. Chromatographic analysis was carried out using BEH C 18 column (Waters) with a mobile phase consisting of acetonitrile and 50% aqueous methanol, 65:35, v/v, each with 0.1% formic acid and using erlotinib (ERL) as an internal standard (IS). DAS quantitation was carried out using multiple reaction monitoring (MRM) with positive ionization of the transitions at m/z 488.03 > 400.92 (DAS), and m/z 394.29 > 278.19 (ERL). Method validation was assessed as per the FDA guidelines for bioanalytical methods for DAS determination within the concentration range 1-500 ng/mL. No significant effect on the oral bioavailability of DAS was reported with any of the studied nutraceuticals. Thus, the concomitant administration of these nutraceuticals with DAS could be considered safe with a necessity to perform more detailed clinical investigations.

UPLC-ESI-MS/MS study of the effect of green tea extract on the oral bioavailability of erlotinib and lapatinib in rats: Potential risk of pharmacokinetic interaction.

Green tea (GT) is one of the most consumed beverages worldwide. Tyrosine kinase inhibitors (TKIs) belong to the oral targeted therapy that gained much interest in oncology practice, among which are erlotinib (ERL) and lapatinib (LAP). Since green tea polyphenols (GTP) are known to be inhibitors of receptor tyrosine kinases, GTE could likely potentiate the anticancer effect of TKIs, but with a possibility of pharmacokinetic (PK) interaction with co-administered TKIs. In this study, the effect of GTE on the PK of ERL/LAP in rats was studied. UPLC-ESI-MS/MS method has been developed and validated for the quantification of ERL and LAP in rat plasma, using gefitinib (GEF) as the internal standard. Plasma samples were treated extensively by protein precipitation (PPT) followed by solid phase extraction (SPE) using octadecyl C 18/14% cartridges. Chromatographic analysis was carried out on Acquity UPLC BEH™ C18 column with a mobile phase consisting of water: acetonitrile (20: 80, v/v), each with 0.15% formic acid. Quantification was performed in the positive electrospray ionization (ESI+) mode with multiple reaction monitoring (MRM) of the transitions m/z 394.29→278.19 (ERL), m/z 581.07→365.13 (LAP), and m/z 447.08→128.21 (GEF). The method was fully validated as per the FDA guidelines showing linearity over the range of 0.4-1000 (ERL) and 0.6-1000 (LAP) ng/mL with very low lower limit of quantification (LLOQ) of 0.4 and 0.6ng/mL for ERL and LAP, respectively. The applicability of the method was extended to perform a comparative study of the PK of ERL/LAP following short-term and long-term administration of GTE, compared with their single oral administration. The results revealed that a significant reduction in the oral bioavailability was recorded with both ERL and LAP following the ingestion of GTE particularly for short-term administration. A reduction in Cmax (AUC) by 67.60% (69.50%) and 70.20% (73.96%), was recorded with short-term administration of GTE, compared with only 16.03% (21.09%) and 13.53% (22.12%) reduction for ERL and LAP, respectively, with long-term administration. Thus patients taking TKIs should preferably avoid drinking GT or ingesting GTE capsules during the period of treatment with TKIs.

Comparative pharmacokinetic profiles of selected irreversible tyrosine kinase inhibitors, neratinib and pelitinib, with apigenin in rat plasma by UPLC-MS/MS.

Neratinib (NER) and pelitinib (PEL) are irreversible tyrosine kinase inhibitors (TKIs) that have been recently employed in cancer treatment. Apigenin (API), among other flavonoids, is known to have antioxidant, anti-proliferative, and carcinogenic effect. API can potentiate the antitumor effect of chemotherapeutic agents and/or alleviate the side effects of many anticancer agents. Since TKIs are mostly metabolized by CYP3A4 enzymes and that API could alter the enzymatic activity, potential drug interactions could be expected following their co-aministration. In the present study, a bioanalytical UPLC-MS/MS method has been developed and validated for the quantification of NER and PEL in rat plasma, using domperidone (DOM) as an internal standard. Sample preparation was carried out using solid phase extraction (SPE) with C18 cartridges with good extraction recovery of not less than 92.42% (NER) and 89.73% (PEL). Chromatographic analysis was performed on a Waters BEH C18 column with a mobile phase composed of acetonitrile and water, (70:30, v/v), each with 0.1% formic acid. Quantitation was performed using multiple reaction monitoring (MRM) of the transitions from protonated precursor ions [M+H]+, at m/z 557.30 (NER), m/z 468.21 (PEL), and at m/z 426.27 (DOM), to selected product ions at m/z 112.05 (NER), m/z 395.22 (PEL), and at m/z 175.18 (DOM). The method was fully validated as per the FDA guidelines over the concentration range of 0.5-200ng/mL with very low lower limit of quantification (LLOQ) of 0.5ng/mL for both NER and PEL. The intra- and inter-day assay precision and accuracy were evaluated for both drugs and the calculated values of percentage relative standards deviations (%RSD) and relative errors (%Er) were within the acceptable limits (<15%) for concentrations other than LLOQ and 20% for LLOQ. The applicability of the method was extended to study the possibility of drug interactions following the oral co-administration of NER/PEL with API. Thus, this study could be readily applied in therapeutic drug monitoring (TDM) of cancerous patients receiving such drug combinations.

Simultaneous determination of erlotinib and tamoxifen in rat plasma using UPLC-MS/MS: Application to pharmacokinetic interaction studies.

Tamoxifen (TAM) is a non-steroidal estrogen receptor antagonist that enhances erlotinib (ERL)-induced cytotoxicity in the treatment of NSCLC. ERL and TAM are metabolized by CYP3A4 enzymes. In addition, both drugs have the potential of altering the enzymatic activity through either inhibition (ERL) or induction (TAM). Thus it was expected that pharmacokinetics (PK) drug-drug interactions (DDIs) could be encountered following their co-administration. In this respect, a bioanalytical UPLC-MS/MS method has been developed and validated for the simultaneous determination of ERL and TAM in rat plasma samples, using ondansetron (OND) as an internal standard (IS). Plasma samples were prepared using mixed mode cationic solid phase extraction (SPE) STRATA™ -X-C 33µm cartridges with good extraction recovery of both drugs from rat plasma (Er% from -13.92 to -3.32). The drugs were separated on a Waters BEH™ C18 column with an isocratic elution using a mobile phase composed of a mixture of acetonitrile and water, each with 0.15% formic acid, in the ratio of 80: 20, v/v. Quantitation was carried out using the positive ionization mode with multiple reaction monitoring (MRM) at m/z 394.20>278.04 (ERL), m/z 372.25>72.01 (TAM), and m/z 294.18>170.16 (OND). The method was fully validated as per the FDA guidelines over the concentration range of 0.2-50ng/mL with very low lower limit of quantification (LLOQ) of 0.2ng/mL for both ERL and TAM. The intra- and inter-day assay precision (in terms of relative standard deviation, RSD) and accuracy (in terms of percentage relative error, % Er) were evaluated for both drugs and the calculated values evaluated at four different concentration levels were within the acceptable limits (<15%) for concentrations other than LLOQ and 20% for LLOQ. The method was successfully applied to the study of possible PK-DDI following the oral administration of ERL and TAM in a combination, compared to their single administration.

Simultaneous determination of selected tyrosine kinase inhibitors with corticosteroids and antiemetics in rat plasma by solid phase extraction and ultra-performance liquid chromatography-tandem mass spectrometry: Application to pharmacokinetic interaction studies.

A sensitive and selective ultra-performance liquid chromatography-tandem mass spectrometry method has been developed and validated for the simultaneous analysis of selected tyrosine kinase inhibitors (TKIs)(gefitinib GEF, erlotinib ERL), corticosteroids (dexamethasone DEX, prednisolone PRED), and the antiemetic ondansetron (OND) in rat plasma samples. After the addition of domperidone (DOM) as internal standard (IS), spiked plasma samples were prepared using the solid phase extraction (SPE) C 18 cartridges. Chromatographic separation was performed on a Waters BEH C18 column with an isocratic elution using a mobile phase composed of acetonitrile and water, each with 0.1% formic acid, (80: 20, v/v), at a flow rate of 0.2 mL/min. Quantitation of the analytes was performed using the multiple reaction monitoring (MRM) mode with the positive ionization mode at m/z 447.25>128.08 (GEF), m/z 394.20>278.04 (ERL), m/z 393.30>147.04 (DEX), m/z 361.29>147.02 (PRED), m/z 294.18>170.16 (OND), and m/z 426.26>175.07 (DOM). The method was validated over the concentration range of 0.025-100 (GEF, ERL, OND) and 0.05-100 ng/mL plasma (PRED, DEX) with very low lower limit of quantification of 0.025 (GEF, ERL, OND) and 0.05 ng/mL (DEX, PRED). The intra- and inter-day precision (RSD%) evaluated at four different concentration levels were within the acceptable limits (<15%). The method provided good extraction recovery of all analytes from rat plasma (Er% from -14.05 to -1.08). The validated method was successfully applied to the pharmacokinetic studies following the oral administration of selected combinations of the studied drugs. This study can be readily applied in therapeutic drug monitoring (TDM) in patients receiving these drug combinations as well as investigation of possible drug interactions between TKIs and DEX/PRED/OND.