Combinatorial Chemistry & High Throughput Screening - Volume 25, Issue 7, 2022

Introduction: The nanofluid is the novelty of nanotechnology to overcome the difficulties of heat transfer in several manufacturing and engineering areas. Fractional calculus has many applications in nearly all fields of science and engineering, which include electrochemistry, dispersion and viscoelasticity. Objectives: This paper focused on the heat transfer of a hybrid nanofluid in two vertical parallel plates and presented a comparison between fractional operators. Methods: In this paper, the fractional viscous fluid model is considered along with physical initial and boundary conditions for the movement occurrences. The analytical solutions have been obtained via the Laplace transform method for the concentration, temperature and velocity fields. After that, we have presented a comparison between Atangana-Baleanu (ABC), Caputo (C) and Caputo-Fabrizio (CF) fractional operators. Results: The comparison of different base fluids (Water, kerosene, Engine Oil) is discussed graphically with respect to temperature and velocity. The results show that due to the high thermal conductivity of water, temperature and velocity are high. While engine oil has maximum viscosity than water and kerosene, thus temperature and velocity are very low. However, due to the improvement in the thermal conductivity with the enrichment of hybrid nanoparticles, the temperature increased, and since the viscosity also increased, the velocity got reduced. Conclusion: Atangana-Baleanu (ABC) fractional operator provided better memory effect of concentration, temperature and velocity fields than Caputo (C) and Caputo-Fabrizio (CF). Temperature and velocity of water with hybridized nanoparticles were high in comparison to kerosene and engine oil.

Background: The present manuscript analyzes the influence of buoyant forces of a conducting time-dependent nanofluid flow through porous moving walls. The medium is also filled with porous materials. In addition to that, uniform heat source and absorption parameters are considered that affect the nanofluid model. Introduction: The model is based on the thermophysical properties of Hamilton-Crosser's nanofluid model, in which a gold nanoparticle is submerged into the base fluid water. Before simulation is obtained by a numerical method, suitable transformation is used to convert nonlinear coupled PDEs to ODEs. Method: Runge-Kutta’s fourth-order scheme is applied successfully for the first-order ODEs in conjunction with the shooting technique. Result: Computations for the coefficients of rate constants are presented through graphs, along with the behavior of several physical parameters augmented by the flow phenomena. Conclusion: The present investigation may be compatible with the applications of biotechnology. It is seen that the inclusion of volume concentration and the fluid velocity enhances near the middle layer of the channel and retards near the permeable walls. Also, augmented values of the Reynolds number and both cooling and heating of the wall increase the rate of shear stress.

Background: Non-newtonian fluids, especially shear thinning fluids, have several applications in the polymer industry, food industry, and even everyday life. The viscosity of shear thinning fluids is decreased by two or three orders of magnitude due to the alignment of the molecules in order when the shear rate is increased, and it cannot be ignored in the case of polymer processing and lubrication problems. Objective: So, the effects of viscosities at the low and high shear rates on the heat and mass boundary layer flow of shear thinning fluid over moving belts are investigated in this study. For this purpose the generalized Carreau model of viscosity relate to shear rate is used in the momentum equation. The Carreau model contains the five parameters: low shear rate viscosity, high shear rate viscosity, viscosity curvature, consistency index, and flow behavior index. For the heat flow, the expression of the thermal conductivity model similar to the viscosity equation due to the non-Newtonian nature of the fluid is used in the energy equation. Methods: On the mathematical model of the problem, boundary layer approximations are applied and then simplified by applying the similarity transformations to get the solution. The solution of the simplified equations is obtained by numerical technique RK-shooting method. The results are compared with existing results for limited cases and found good agreement. Results: The results in the form of velocity and temperature profiles under the impact of all the viscosity’s parameters are obtained and displayed in graphical form. Moreover, the boundary layer parameters such as the thickness of the regions, momentum thickness, and displacement thickness are calculated to understand the structure of the boundary layer flow of fluid. Conclusion: The velocity and temperature of the fluid are decreased and increased respectively by all viscosity’s parameters of the model. So, the results of the boundary layer fluid flow under rheological parameters will not only help engineers to design superior chemical equipment but also help improve the economy and efficiency of the overall process.

The recent COVID-19 pandemic has sparked great interest in strengthening the immune system, especially by the consumption of widely available natural dietary supplements. Because of this popularity, it was suggested that the sales of these products would grow significantly in the year 2021, especially for those who are unable or unwilling to receive COVID-19 vaccines. Among the many botanicals, Sambucus nigra L. (Elderberry) and Echinacea purpurea (L.) Moench (Echinacea) have especially shown great popularity. Various in vivo and in vitro tests of S. nigra and E. purpurea extracts and constituents have confirmed the botanicals’ influence on proinflammatory cytokines, viral infections, and flu symptoms, proving their immunomodulatory and antiviral effects. Although there have been promising results with S. nigra and E. purpurea containing supplements, thorough monitoring of the sanitary production, demand, and related side effects after consumption is required. Further research and development of the supplements in accordance with the pandemic are also advised.

Background: Red mamey is the fruit of P. sapota, a tree found in Mesoamerica and Asia. This fruit is considered a nutraceutical due to its multiple beneficial health including antiamyloidogenic activity and potential anti-tumorigenic property. Red mamey contain a variety of carotenoids including novel ketocarotenoids such as sapotexanthin and cryptocapsin. A ketocarotenoid is a chemical compound with a carbonyl group present in the β-ring or in the double bond chain of a carotenoid. In red mamey, the 3'-deoxy-k-end group in sapotexanthin has proven to be an important pro-vitamin A source, which is essential for maintaining a healthy vision and cognitive processes. Objective: This work reviews the current knowledge about the chemistry and biological activities of carotenoids in red mamey. Method: An exhaustive extraction is the most usual methodology to isolate and thoroughly characterize the carotenoids present in this fruit. High performance liquid chromatography is used to determine the profile of total carotenoids and its purity, while atmospheric pressure chemical ionization was used to determine their molecular weight and nuclear magnetic resonance determined their structure. Result: For each 100 g of fresh weight, 0.12 mg of total carotenoid from this fruit can be obtained. Out of the more than 47 reported carotenoids in red mamey, only 34 have a detailed characterization. Conclusion: It is important to continue studying the chemical composition and biological activity of this unique tropical fruit with commercial and nutritional value.

Background: The fruit pulp decoction of Crescentia cujete, commonly known as calabash, is traditionally used for the treatment of several respiratory diseases and is available as syrup formulations. Unfortunately, there is no detailed investigation on the analytical methods for warranting the quality of these products. Aims and objectives: To develop and validate an appropriate analytical method for the simultaneous quantification of trans-cinnamic acid, 4-hydroxybenzoic acid, verbascoside and 6- epi-aucubin in the decoction and commercial cough syrups of Crescentia cujete fruit. Materials and Methods: A reversed-phase ultra-high-performance liquid chromatographic method coupled to a diode array detector (UPLC-DAD) was validated following the ICH guidelines. The chromatographic analysis was performed using a C18 column, the mobile phase system consisted of water and acetonitrile containing 0.1% formic acid, and UV chromatograms were recorded from 200 to 400 nm. Results: A new UPLC-DAD method was validated for the simultaneous quantification of transcinnamic acid, 4-hydroxybenzoic acid, verbascoside and 6-epi-aucubin in calabash-derived products. After successful validation, this method was applied for the quantification of the selected chemical markers in an in-house decoction and three commercial cough syrups. Among the selected chemical markers, 6-epi-aucubin was the main compound in the calabash decoction, while trans-cinnamic acid and 4-hydroxybenzoic acid were the major compounds in the commercial products. Verbascoside and 6-epi-aucubin were below the limit of quantification in all syrup samples. Conclusion: The proposed method was successfully applied for the analysis of three commercial syrup formulations and can be useful for standardization and quality control of raw and pharmaceutical calabash preparations.

Background: One of the main problems that fruit health has gone through in recent years is the problematic eradication of their fungal pathogens during crops or the post-harvest stage. This concerns the whole world because it represents huge production losses, fruit export restrictions, and consumer distrust. Consequently, new alternatives are sought to avoid the increasing use of fungicides that cause important damage to fruit consumers and the environment. One of the alternatives to solve this problem could be exploring plants and their active compounds applied to the treatment of fruit health. Materials and Methods: This article describes peach production worldwide and particularly in Argentina, in addition to the main fungal rot that causes the greatest economic losses. Furthermore, experimental in-vitro studies of 69 extracts obtained from 18 plants growing in the central region of Argentina were displayed against the devastating fungus Monilinia fructicola, which greatly affects stone fruits. A simple and effective method developed in agar plate was applied to evaluate a large number of samples in a short time. Results: The results showed that approximately 36% of the samples tested were strongly active against this pathogen, 12% were moderately active, and 52% demonstrated to be inactive. Conclusion: These findings support the possible use of natural products for fruit health and the importance of deepening in this field of science.

The enhanced applications of Schiff bases metal complexes of amino acid derivatives have captured the attention of researchers for the synthesis of leucine derivatives of Schiff bases metal complexes. Amino acids are considered to be essential part of food supplements as well as derivatives of Schiff bases in coordination chemistry due to their donor ability. The leucine derivatives Schiff bases ligand have been synthesized by condensation reaction between amine of leucine with aldehyde or ketone bearing molecules attached with them. These complexes were characterized by different spectroscopic tools in order to confirm their structural geometries. The structural geometries are considered to be very important in order to improve the antimicrobial potential of leucine derivative metal complexes. By taking into account the antimicrobial potential of titled compounds, a comprehensive review of leucine derivatives of Schiff bases metal complexes has been compiled.

Oxalis corniculata (Oxalidaceae) is a small decumbent and delicate appearing medicinal herb flourishing in warm temperate and tropical domains such as Pakistan and India. Main bioactive chemical constituents of Oxalis plant include several alkaloids, flavonoids, terpenoids, cardiac glycosides, saponins, and phlobatannins, along with steroids. Due to its polyphenolic, glycosides and flavonoid profile, it is proved to be protective in numerous ailments and exhibit various biological activities such as anti-fungal, anti-cancer, anti-oxidant, antibacterial, anti-diabetic, and cardioprotective. Moreover, bioactive phytochemicals from this plant possess significant wound healing potential. Our current effort intends to emphasize on the immense significance of this plant species, which have not been the subject matter of clinical trials and effective pharmacological studies, even though its favored usage has been stated. This review proposes that Oxalis corniculata possess a potential for the cure of various diseases. However, further researches on isolation and characterization of bioactive compounds along with pre-clinical trials are compulsory to figure out its pharmacological applications.

Background: Fagonia arabica, belonging to family Zygophyllaceae, is a medicinal plant widely distributed in the desert areas of the world, including Saudi Arabia, Pakistan, India and South Africa. The present review aims to explore the published information on the traditional uses, ethnobotanical knowledge, phytochemistry and various biological activities like antioxidant, antimicrobial, thrombolytic activities and anticoagulant effects of Fagonia arabica with critical analysis on the gaps and future perspectives. Method: A literature survey was performed by searching the digital libraries and the scientific databases including Scopus, Google Scholar, SciFinder, ACS, Web of Science and published books. Results: Fagonia arabica plant has been reported to have a wide range of traditional uses in sore mouth, smallpox, hematological, neurological, endocrinological, inflammatory, cooling agent in stomatitis, vertigo and endothermic reaction in the body. Several bioactive constituents, including glycosides, flavonoids, terpenoids, saponins, alkaloids and trace elements, were recorded from Fagonia arabica plant. The isolation and identification of two flavonoid glycosides (kaempferol-7- O-rhamnoside and acacetin-7-O-rhamnoside) were also reported. Fagonia arabica has been studied for its wide range of biological activities, which include antioxidant, antimicrobial, cardioprotective and anticoagulant. Conclusion: It is apparent from the literature that Fagonia arabica plant possesses a wide range of medicinal and pharmacological uses and has been studied for its various pharmacological activities and medicinal applications. Critical analysis reveals that the plant has huge potential for pharmaceutical and pharmacological applications.

Introduction: Bacterial resistance to multiple drugs is increasing at an alarming rate in the current era and nanotechnology is one of the effective and novel approaches to overcome drug resistance. Methods: Zinc Oxide Nanoparticles (ZnO NPs) have stronger antibacterial activity and are regarded as bio-safe nanomaterial. The aim of the present study is to synthesize the ZnO NPs using Aloe vera leaves extract and to investigate the synergistic effects and antioxidant actions of biosynthesized ZnO NPs against gram-negative bacteria E.coli and K. pneumoniae. The synergistic effect of β-lactam antibiotics (meropenem and ciprofloxacin) was tested along with ZnO NPs using Kirby’s disc diffusion assay. The antioxidant activity was investigated by α, α-diphenyl-β- picrylhydrazyl (DPPH) method. Results: Results of the study revealed that the antibacterial activity of the selected antibiotics was much enhanced by ZnO NPs than the antibiotics alone. The resistant antibiotic (ciprofloxacin) became sensitive when combined with ZnO NPs. The antioxidant activity reveals that biosynthesized ZnO NPs possess significantly higher (p<0.05) antioxidant activity (77%). Conclusion: The findings reveal that biosynthesized ZnO NPs have a much more eco-friendly approach. It can act as a strong potentiator of β-lactam antibiotics and put forward the possibility to use them effectively in targeted drug delivery, pharmaceuticals and biomedical fields.

Background: The presence of biofilm formation exoU gene is a significant challenge to infection control management in hospitals and exposure by Pseudomonas aeruginosa may lead to further spread and development of antimicrobial resistance. Methods: Out of 227 samples, 40 clinical isolates of P. aeruginosa were collected from patients attending public hospitals (Rizgary, Teaching hospital, Laboratory center, Raparin, Nanakaly hospitals) in Erbil city, Iraq over a period during June 2018 to March 2019 and were fully characterized by standard bacteriological procedures and antimicrobial susceptibility test and ESBL has been carried out by Vitek 2 compact system and by Vitek 2 compact system. The identification has been verified by all isolates as P. aeruginosa by using 16S rDNA with product size (956pb). Results: A high rate of resistance was seen against Penicillin, Lincomycin, Piperacillin and Chloramphenicol and Rifampicin (100 %), whereas Imipenem (5%) was found to be the most effective antimicrobial drug. Of all P. aeruginosa isolates, 30 (75% %) were identified as MDR, approximately 9 (22.5%) isolates were resistant to 9 drugs in burn samples. Quantitative biofilm determination using the Congo red method revealed that 28 isolates (70%) produced biofilm, biofilm production was significantly higher among MDR P. aeruginosa isolates while coproduction of Extended Spectrum β-lactamase (ESBL) together with Metallo β-lactamase (MBL) ESBLs MBLs was recorded in 52.5% of the isolates. Altogether 40 isolates were processed for the analysis by PCR assays and showed that 26 (70%) of P. aeruginosa isolates harboured the exoU encoding gene with product size (204) pb was more commonly seen in isolates obtained from burn isolates. In addition, exo U gene was significantly associated with the higher MDR (80%), 8 isolates (76.9%) had exoU gene with ESBL and (65%) had MBL and the same for MDR (80.8%) in samples for burning. Conclusion: Our results showed surveillance of P. aeruginosa resistance against antimicrobial and ESBL and MBL is fundamental to monitor trends in susceptibility patterns and appropriately guide clinicians in choosing empirical or directed therapy.

Background: Bacteria Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) are the main causes of Urinary Tract Infections (UTIs). This research aims to investigate the isolation of etiologic agents from patients with UTIs. In addition, it tries to investigate the incidence of ESBL genes in an etiologic agent. Methods: This study included 1,000 positive growth isolates. Accordingly, the predominant pathogens associated with urinary tract infections, i.e., Gram-negative, were the main isolates from UTI patients, including E. coli, K. pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Staphylococcus aureus, and Enterococcus faecalis. Results: Among suspicious cases of urinary tract infections, the results showed that 15.2% of the patients had UTIs, with female patients in the childbearing age group being more affected. E. coli (644; 64.4%) and K. pneumoniae (322; 32.2%) were shown to be more isolated. Among 936 (93.6%) ESBL producing bacteria, 614 (61.4 %) were E. coli, and 32.2% were K. In addition, high resistance was recorded for antibiotics Cefotaxime (85.7 %), Cefepime (85.7%), Ciprofloxacin (83.1%), and Kanamycin (77.9%). Most ESBL-producing K. pneumoniae were multidrug-resistant (MDR). Besides, nitrofurantoin, gentamycin, and imipenem were the most effective antibiotics against ESBL-producing E. coli isolates. Conclusion: Research shows that high rates of MDR Escherichia coli infections in our hospital were the frequent causes of UTIs. Nitrofurantoin and aminoglycosides were the most beneficial first-line drugs to be prescribed in UTI cases. It is recommended that regular investigations should be carried out on drug resistance in all isolates to formulate helpful antibiotic treatment policies in Iraq. Thus, it is important to determine ESBL prevalence in urine E. coli and K. pneumoniae isolates as it has a great impact on the selection of suitable antibacterial agents. In short, more than half of ESBL producers have Multiple Drug Resistance (MDR).

Aims: The aim of the study is to develop advanced antibacterial agents as nanoparticles instead of antibiotics due to the emergence of antimicrobial resistance. Background: Pseudomonas aeruginosa is capable of causing many diseases, including serious bacterial pneumonia. There is a need for an efficient antibacterial agent to kill these pathogens. Objective: The objective of the study is the synthesis of advanced antibacterial agents as nanoparticles for biomedical applications that can play a vital role to kill Gram-negative bacteria (Pseudomonas aeruginosa). Methods: A novel fabrication growth of hydrophilic spiky gold nanoparticles (SGNPs) via reduction method is reported. Results: Surface plasmon resonance peak of the synthesized SGNPs was tuned under near infrared range. The SGNPs have anisotropic and spiky morphology with 68 nm size and -58 mV surface charge and are pure, having adsorption of the organic material. Pseudomonas aeruginosa treated with synthesized SGNPs showed 60% bacterial death at the concentration of 100 μM. Conclusion: This work consists of novel synthesis of SGNPs via safe and simple reduction method. The synthesized SGNPs exhibit strong antibacterial activity against the Gram negative bacteria Pseudomonas aeruginosa measured using microplate assay test. The result showed that these SGNPs are ideal for biomedical applications.