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Theophylline, a nitrogen-containing heterocycle, serves as a promising focal point for medicinal researchers aiming to create derivatives with diverse pharmacological applications. In this work, we present an improved synthetic method for a range of theophylline-1,2,4-triazole-S-linked N-phenyl acetamides (4a‒g) utilizing ultrasound-assisted synthetic approach. The objective was to assess the effectiveness of synthesized theophylline-1,2,4-triazoles (4a‒g) as inhibitors of HCV serine protease and as antibacterial agents against B. subtilis QB-928 and E. coli AB-274. Theophylline-1,2,4-triazoles were obtained in good to excellent yields (69%–95%) in a shorter time than conventional approach. 4-Chlorophenyl moiety containing theophylline-1,2,4-triazole 4c displayed significantly higher inhibitory activity against HCV serine protease enzyme (IC50 = 0.015 ± 0.25 mg) in comparison to ribavirin (IC50 = 0.165 ± 0.053 mg), but showed excellent binding affinity (−7.55 kcal/mol) with the active site of serine protease, better than compound 4c (−6.90 kcal/mol) as well as indole-based control compound 5 (−7.42 kcal/mol). In terms of percentage inhibition of serine protease, 2-chlorophenyl compound 4b showed the maximum percentage inhibition (86%), more than that of the 3,4-dichlorophenyl compound 4c (76%) and ribavirin (81%). 3,4-Dimethylphenyl-based theophylline-1,2,4-triazole 4g showed the lowest minimum inhibitory concentration (MIC = 0.28 ± 0.50 μg/mL) against the B. subtilis bacterial strain as compared to the standard drug penicillin (MIC = 1 ± 1.50 μg/mL). The other 4-methylphenyl theophylline-1,2,4-triazole 4e (MIC = 0.20 ± 0.08 μg/mL) displayed the most potent antibacterial potential against E. coli in comparison to the standard drug penicillin (MIC = 2.4 ± 1.00 μg/mL). Molecular docking studies further helped in an extensive understanding of all of the interactions between compounds and the enzyme active site, and DFT studies were also employed to gain insights into the molecular structure of the synthesized compounds. The results indicated that theophylline-linked triazole derivatives 4b and 4c showed promise as leading contenders in the fight against the HCV virus. Moreover, compounds 4e and 4g demonstrated potential as effective chemotherapeutic agents against E. coli and B. subtilis, respectively. To substantiate these findings, additional in vivo studies and clinical trials are imperative, laying the groundwork for their integration into future drug design and development.

The tyrosinase enzyme has a vital role in the browning of vegetables and fruits and the biosynthesis of melanin. In this work, we synthesized a diverse library of coumarin–triazole hybrids, and these compounds were characterized by using suitable analytical techniques. Our research work extends beyond the synthetic effort to explore the therapeutic potential of these compounds. We put the synthesized compounds through meticulous in vitro screening against the tyrosinase enzyme, and these coumarin derivatives evinced good IC50 values in the range of 0.339 ± 0.25 µM to 14.06 ± 0.92 µM. In the library of synthesized compounds, six compounds were found to be more potent than standard ascorbic acid (IC50 = 11.5 ± 1.00), and among them, 17e and 17f, being the most active, exhibited remarkable anti-tyrosinase potential, with IC50 values of 0.339 ± 0.25 μM and 3.148 ± 0.23 μM, respectively. Furthermore, an in silico modeling study was carried out to determine the key interactions of these compounds with the tyrosinase protein (PDB ID: 2Y9X) and thus to authenticate our experimental findings. The quantitative SAR studies exhibited a good correlation between the synthesized derivatives of coumarin and their anti-tyrosinase activity. The docking studies verified the experimental results, and ligand 17e showed good interaction with the core residues of tyrosinase. This study not only expands the field of coumarin–triazole hybrid synthesis but also provides valuable insights for the development of novel tyrosinase inhibitors.

A series of novel triazole analogs (10a-k) bearing piperidine were synthesized in an aprotic solvent on the most effective pharmacophore with acetylcholinesterase (AChE) and α-glucosidase inhibitory activity. Triazole analogs (10a-k) were obtained in excellent yields (75–90 %) and characterized by EI-MS, IR, 13C NMR and 1H NMR. The newly synthesized triazole analogs (10a-k) showed potent AChE inhibitory activity in the range of Ki = 0.0155 ± 1.25 µM to 0.557 ± 0.50 µM, IC50 = 0.031 ± 0.85 to 0.537 ± 0.76 µM than Eserine (0.04 ± 0.001 µM) having strong electron-withdrawing fluorine group on the pyridine ring was recorded as a most potent inhibitor of AChE while (%) inhibition against α-glucosidase was ranging between 52.36 ± 1.67 to 85.35 ± 1.39. The kinetic study predicted that triazole analogs (10a-k) followed the un-competitive and mixed type of inhibition against AChE. In silico molecular docking was performed at the active site of the AChE co-crystal structure (PDB ID:1NEN). The results of molecular docking corelate will with the experimental findings.

Piperazine is a privileged moiety that is a structural part of many clinical drugs. Piperazine-based scaffolds have attracted the attention of pharmaceutical and medicinal scientists to develop novel, efficient therapeutic agents owing to their significant and promising biological profile. In the current study, an ecofriendly ultrasonic-assisted synthetic approach was applied to achieve a novel series of 1-tosyl piperazine dithiocarbamate acetamide hybrids 4a–4j, which was evaluated for in vitro tyrosinase inhibition and thrombolytic and hemolytic cytotoxic activities. Among all the piperazine-based dithiocarbamate acetamide target molecules 4a–4j, the structural analogs 4d displayed excellent tyrosinase inhibition efficacy (IC50 = 6.88 ± 0.11 µM) which was better than the reference standard drugs kojic acid (30.34 ± 0.75 µM) and ascorbic acid (11.5 ± 1.00 µM), respectively, which was further confirmed by in silico induced-fit docking (IFD) simulation Good tyrosinase activities were exhibited by 4g (IC50 = 7.24 ± 0.15 µM), 4b (IC50 = 8.01 ± 0.11 µM) and 4c (IC50 = 8.1 ± 0.30 µM) dithiocarbamate acetamides, which were also better tyrosinase inhibitors than the reference drugs but were less active than the 4d structural hybrid. All the derivatives are less toxic, having values in the 0.29 ± 0.01% to 15.6 ± 0.5% range. The scaffold 4b demonstrated better hemolytic potential (0.29 ± 0.01%), while a remarkably high thrombolytic chemotherapeutic potential was displayed by analog 4e (67.3 ± 0.2%).

In this study, we have investigated ciprofloxacin-based acetanilides for their in-vitro inhibitory study against gram +ve, -ve bacteria and serine protease activity. The compounds 4e and 4g showed excellent antibacterial activity against Bacillus subtilis with a zone of inhibition (ZI) values of 40 ± 0.9 mm, 37 ± 1.4 mm and with MIC values of 4.0 ± 0.78 mg/mL, 3.0 ± 0.98 mg/ML respectively, while 4a and 4i were found most active against Escherichia coli, with ZI values 38 ± 0.1 mm, 46 ± 1.8 mm and with MIC values of 1.0 ± 0.25 mg/mL, 1.0 ± 0.23 mg/mL respectively. All derivatives (4a-j) significantly inhibited the catalytic activity of serine protease, while 4a exhibited a maximum (100%) inhibitory effect at 96 minutes having 22.50 minutes [Formula: see text], and non-competitive inhibition with 0.1±0.00μM Ki. The IFD/MM-GBSA studies highlighted the binding mode of 4a for protease inhibition and indicated improved binding affinity with -107.62 kcal/mol of ΔGbind.

The Cr ion doping effect on various properties of Cr doped BaCrxFe12-xO19 nanoparticles was investigated, which were synthesized via a facile microemulsion approach and properties were studied using XRD, SEM, FTIR, Raman, photoluminescence and UV–visible techniques along with dielectric, optical and ferroelectric properties. The BaCrxFe12-xO19 structure was hexagonal involving P63/mmc space group with average crystalline size of 9–18 nm. The NPs exhibited agglomerated platelet heterogeneous morphology. The presence of the Ba-O-Fe functional group was also confirmed by FTIR analysis. The PL analysis revealed that the doping reduced the recombination rate and charge (e−-h+) separation is facilitated. The coercivity (Hc) and saturation polarization (Ps) increased with doping content and dielectric loss reduces with frequency and dopant concentration. The dopant contents also increased the AC conductivity and the optical bandgap found in 1.75–2.83 (eV) range. The BaCrxFe12-xO19 exhibited a significantly higher photocatalytic efficiency versus BaFe12O19, and 91 % CV dye was degraded in 90 min under visible light irradiation. Additionally, a recycling experiment was conducted to confirm the stability of the prepared photocatalyst and Cr doped BaCrxFe12-xO19 exhibited excellent stability and reusability. The Cr doping affected the dielectric, optical and ferroelectric properties and based on photocatalytic properties of BaCrxFe12-xO19, it has potential applications for the destruction of dyes in wastewater under visible light exposure, which will make the process highly feasible for photocatalytic applications.

A series of Ni doped SrNixFe12-xO19 (x = 0.0, 0.05, 0.10, 0.15, 0.20, 0.25) hexaferrites were fabricated through facile micro-emulsion approach and doping content effect was investigated based on structural, dielectric, optical and photocatalytic properties. The prepared materials were characterized via X-ray diffraction (XRD), Raman, Fourier transformed infrared (FTIR), photoluminescence (PL) and UV–vis techniques. The Ni doped SrFe12O19 structure was hexagonal having space group P63/mmc with mean crystallite size in 34–50 nm range. Ferroelectric polarization, coercivity and Remnant polarizations were increased with Ni doping. Dielectric analysis showed the higher values of dielectric parameters with dispersion in low frequency region, which were independent of at high frequency. Optical bandgap was reduced on substitution, which was in 2.31–1.66 eV range, which was in good association with decline in PL analysis. The PCA (photocatalytic activity) of pure SrFe12O19 (SFO) and doped SFNO5 (x = 0.25) material was assessed for removal of crystal violet (CV) dye under visible light illumination. The SFNO5 showed much better PCA and 91 % dye was removed in 90 min with a rate constant of 2.337 × 10-2 min−1 versus pristine SFO (only 55 % with rate constant 8.02 × 10-3 min−1). Results revealed that tuned bandgap and enhanced AC conductivity of doped materials make it crucial candidates for optoelectronic and SOFCs (Solid oxide fuel cell) applications. Owing to the excellent PCA and magnetically separable nature, SrNixFe12-xO19 has potential for the dyes removal from the effluents under solar light irradiation, which could be more economically versus UV based photocatalytic process.

In this study, a series of novel benzofuran-based 1,2,4-triazole derivatives (10a–e) were synthesized and evaluated for their inhibitory potential against acetylcholinesterase (AChE) and bacterial strains (E. coli and B. subtilis). Preliminary results revealed that almost all assayed compounds displayed promising efficacy against AChE, while compound 10d was found to be a highly potent inhibitor of AChE. Similarly, these 5-bromobenzofuran-triazoles 10a–e were screened against B. subtilis QB-928 and E. coli AB-274 to evaluate their antibacterial potential in comparison to the standard antibacterial drug penicillin. Compound 10b was found to be the most active among all screened scaffolds, with an MIC value of 1.25 ± 0.60 µg/mL against B. subtilis, having comparable therapeutic efficacy to the standard drug penicillin (1 ± 1.50 µg/mL). Compound 10a displayed excellent antibacterial therapeutic efficacy against the E. coli strain with comparable MIC of 1.80 ± 0.25 µg/mL to that of the commercial drug penicillin (2.4 ± 1.00 µg/mL). Both the benzofuran-triazole molecules 10a and 10b showed a larger zone of inhibition. Moreover, IFD simulation highlighted compound 10d as a novel lead anticholinesterase scaffold conforming to block entrance, limiting the swinging gate, and disrupting the catalytic triad of AChE, and further supported its significant AChE inhibition with an IC50 value of 0.55 ± 1.00 µM. Therefore, compound 10d might be a promising candidate for further development in Alzheimer’s disease treatment, and compounds 10a and 10b may be lead antibacterial agents.

A series of Sr1-xZnxFe1-yNiyO19 with composition of x = 0.0, 0.15, 0.30, 0.45, 0.60 and y = 0.0, 0.2, 0.3, 0.4, 0.5 were prepared using micro-emulsion approach and characteristics were studied by XRD, FTIR and UV–vis techniques. The effect of doping was investigated based on the optical, dielectric, structural and photocatalytic properties of Sr1-xZnxFe1-yNiyO19. XRD analyses confirmed the hexagonal crystal structure of pure and doped SrFe12O19 NPs. The lattice parameters, X-ray density, porosity, bulk density and crystallite size of Sr1-xZnxFe1-yNiyO19 and SrFe12O19 were compared. The FTIR analysis confirmed that there was shifting of peaks from region of lower to higher frequency in Sr1-xZnxFe1-yNiyO19, due to the reduction of the size of grains after doping. The current–voltage I-V data shows that there is gradual increase in the conductivity of as prepared doped-material, but the reverse was the case for resistivity, which exhibit good conducting behavior of the fabricated material. Evaluation of the dielectric properties of the samples shows that the AC conductivity and dielectric constant enhanced, while tangent, dielectric loss and resistivity decreased with concentration of the dopants (Zn and Ni). These excellent properties of doped material can be used for the fabrication of various electronic, electrical, microwave and high frequency devices applications. The photocatalytic activity of Sr1-xZnxFe1-yNiyO19 and SrFe12O19 was tested against methyl green (MG) dye. Results revealed that Sr1-xZnxFe1-yNiyO19 degraded 72.23 % of MG dye in 60 min under the exposure of solar light. The recyclability and usability tests revealed that there was a minute loss after successive four runs. Sr1-xZnxFe1-yNiyO19 might have potential applications as a photo-catalyst under solar light irradiation.

Background: The Butyrylcholinesterase (BChE) is widely known chemical biomarkers to identify pesticide exposure. The presence of cholinesterase in the serum of female cotton pickers indicate the exposure to organophosphate and carbamate pesticides. Assessment of the cholinesterase levels in agricultural workers provides the most important indicator for the initiation of medical treatment. Objectives: The present study was designed to compare the activity of serum BChE among female cotton pickers (exposed group) and non-cotton pickers (non-exposed group). Methodology: The level of serum BChE of 100 female cotton pickers was compared with that of 100 non-cotton picker females. A self-designed questionnaire was used for the collection of primary data after a review of related studies. The R computer program (a language and environment for statistical computing and graphics) was used for the analysis of primary data. Results: The level of BChE was recorded, and the means for the two groups were compared. The exposed mean was 5975.90 ± 541.85U/L, and the non-exposed mean was 6981.76 ± 782.92U/L and the difference was found to be statistically significant (p < 0.001). The result of the current study confirmed the negative association between decreased serum BChE and pesticide exposure. It was also found that 76% of female cotton pickers did not wash their hands before eating during the cotton picking. Similarly, 81% of pickers did not use gloves for their safety. Conclusion: The inappropriate use of Personal Protective Equipment (PPEs) and the lack of awareness regarding pesticides' adverse the impact on female cotton pickers' health are significant factors of pesticide exposure.

Angiotensinogen (AGT) is one of the most significant enzymes of the renin-angiotensin-aldosterone system (RAAS) which is involved in the regulation and maintenance of blood pressure. AGT is involved in the production of angiotensin I which is then converted into angiotensin II that leads to renal homeostasis. However, various genetic polymorphisms in AGT have been discovered in recent times which have shown an association with various diseases. Genetic polymorphism increases the level of circulating AGT in blood which exaggerates the effects produced by AGT. The associated diseases occur due to various effects produced by increased AGT levels. Several cardiovascular diseases including myocardial infarction, coronary heart disease, heart failure, hypertrophy, etc. are associated with AGT polymorphism. Other diseases such as depression, obesity, diabetic nephropathy, pre-eclampsia, and liver injury are also associated with some variants of AGT gene. The most common variants of AGT polymorphism are M235T and T174M. The two variants are associated with many diseases. Some other variants such as G-217A, A-6G, A-20C and G-152A, are also present but they are not as significant as that of M235T and T174M variants. These variants increase the level of circulating AGT and are associated with prevalence of different diseases. These diseases occur through various pathological pathways, but the initial reason remains the same, i.e., increased level of AGT in the blood. In this article, we have majorly focused on how genetic polymorphism of different variants of AGT gene is associated with the prevalence of different diseases.

Iron oxide nanoparticles (Fe2O3 NPs) were fabricated through green route using pomegranate (Punica granatum) seeds extract. The Fe2O3 NPs were characterized by UV–vis, XRD, EDX, SEM and AFM techniques. The adopted green rout furnished semi spherical Fe2O3 NPs, uniformly distributed and particle size in the range of 25–55 nm. The LCMS/MS was performed for the identification of biomolecule present in the extract of pomegranate seeds and p-hydroxy benzoic acid, gallic acid, methyl gallate, catechin, kaempferol-3-O-sophoroside, 3-deoxyflavonoids, magnolol, ferulic acid, vanillic acid and pinocembrin along with other minor constituents were detected in the extracts using for Fe2O3 NPs. The synthesized Fe2O3 NPs showed excellent photocatalytic activity against reactive blue under UV light irradiation and maximum degradation of 95.08% was achieved with 56 min of reaction time. In view of promising activity, the Fe2O3 NPs could be used photocatalyst for the degradation of dyes in wastewater and pomegranate seeds extract can be applied as eco-benign and cost effective approach for Fe2O3 NPs synthesis. Keywords: Punica granatum, Green synthesis, Iron oxide nanoparticles, Photocatalysis, Dye degradation

La1-xBixCo1-yFeyO3 perovskite was prepared by micro-emulsion method and effect of the Fe and Bi doping on the properties of perovskite was investigated. As-prepared perovskite was characterized by X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), Energy-dispersive X-ray (EDX) and atomic force microscopy (AFM) techniques. La1-xBixCo1-yFeyO3 perovskite showed distorted rhombohedral structure and particle size was in the range of 33.05–57.41 nm. Doping of perovskite with Bi and Fe enhanced the direct current (DC) resistivity. Dielectric parameters were studied in the range of 20 to 20 MHz and vibrating magnetometery revealed that the Mr and Ms values were higher for La0.75Bi0.25Co0.75Fe0.25O3, whereas LaCoO3 showed higher value of Hc. Photocatalytic activity (PCA) was evaluated by degrading congo red dye and Bi and Fe doped perovskite showed significantly higher activity versus LaCoO3. Results revealed that the doping of LaCoO3 with Bi and Fe enhanced the magnetic, dielectric and catalytic properties of LaCoO3. Keywords: LaCoO3 perovskite, Bi and Fe doping, Characterization, Properties, Photocatalysis

This manuscript reports successful C-H nickellation of the aryl phosphinites (i-Pr2P(O-aryl) derived from un-substituted/substituted phenols: C6H5OH, 4-R-C6H4OH (R = F, MeO). Nickellation was observed with the phosphinites at an ortho-C-H position to generate Br-bridged dimers [{κP,κC-(i-Pr)2PO-aryl}cNi(μ-Br)]2 (C1-C3). While conversion of monomeric complexes from dimeric cyclonickellated complexes, functionalization behaviour was studied under inert atmosphere by reacting synthesized complexes with R2PX in various solvents. In order to understand the feasibility of the reaction and to evaluate the properties of product of insertion, phosphinite-phosphine nickel complexes were also approached from a second side. Appearance of specific signals in NMR spectra of products, provided strong evidences of formation of the target products exhibiting fluxional behaviour.

Chromium-doped cobalt perovskite (Co1−xCrxFeO3) were fabricated via micro-emulsion approach. Phase, morphology and elemental composition of fabricated materials were confirmed by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning electron microscopy (SEM) and energy dispersive X-rays spectroscopy (EDX). The X-ray density, bulk density, porosity, cell volume and lattice parameters were calculated, the average crystallite size was found to be 28 nm. EDX analysis confirmed the occurrence of Fe, Cr, Co and O in the fabricated perovskite. The Wagner and Koop’s theory was used to evaluate the dielectric loss factors and dielectric constant. By increasing the dopant concentration, dielectric constant was decreased and appearance of polarization electric loops implies the ferroelectric nature of Co1−xCrxFeO3 NPs, which enables them to be used in multi-layered capacitors and storage devices. Furthermore, the band gap energy was assessed by empoying Tauc plot, which was found to be 1.88 eV. Finally, the photocatalytic activity (PCA) was appraised using MB (methylene blue) dye as model, which was degraded up to 55.38% in 80 min under solar light irradiation. Results depicted that the Co1−xCrxFeO3 NPs dielectric, ferroelectric and catalytic characteristics were dependent to dopant content.

The therapeutic potential of whitish glaucous sub-shrub Haloxylon griffithii (H. griffithii), abundantly present in southern regions of South Asia, has been neglected. The current study aimed to assess the phytochemicals and pharmacological potential of native and gemm forms of H. griffithii. Results of antimicrobial activity revealed that all tested bacteria were susceptible at concentrations ≤50 µg/mL, while tested fungal species were susceptible at ≤25 µg/mL. The values of minimum bactericidal concentrations (MBCs) ranged between 10.75 ± 0.20 to 44.25 ± 0.42 µg/mL, 8.25 ± 0.02 to 28.20 ± 0.80 µg/mL. The value of minimum inhibitory concentration (MIC) of all microbial species was ≤100 µg/mL and the antibiotic mechanism showed that both extracts were highly bactericidal and fungicidal. Results of average log reduction of viable cell count in time kill assay indicated that Pseudomonas aeruginosa (P. aeruginosa) NCTC 1662, Candida albicans (C. albicans) IBL-01, Candidakrusei (C. krusei) ATCC 6258, and Aspergillus flavus (A. flavus) QC 6158 were the most susceptible microbial species. High performance liquid chromatography (HPLC)-based quantification confirmed the presence of gallic acid p.coumeric acid catechin, vanillin, ellagic acid, and salicylic acid, while in native extract only gallic acid. Native and gemm extracts exhibited excellent radical scavenging potential measured by 1,1-diphenyl-2-picryl-hydrazyl radical scavenging assay. Significant thrombolytic activity was found in both extracts with negligible haemolytic activity. Highest percent (%) clot lysis was observed with gemm extracts (87.9 ± 0.85% clot lysis). In summary, we infer that valuable evidence congregated can be exploited for better understanding of gemm H. griffithii’s health benefits, further, to increase its utility with enriching dietary sources of health-promoting compounds.

A series of La _1−x Ce _x Ni _1−y Fe _y O _3 (x, y = 0.00–0.25) NPs was fabricated via micro-emulsion route and effect of doping was investigated on the basis of optical, photocatalytic and structural properties. The as-synthesized NPs were characterized via XRD, Raman analysis, SEM and UV–visible techniques. The XRD results confirmed the rhombohedral perovskite phase particles with particles of 60–80 nm range. UV–vis absorption edge showed significant red shift thereby tuning the band gap from 2.77 to 2.64 eV. The photocatalytic effectiveness of LaNiO _3 and La _0.80 Ce _0.20 Ni _0.80 Fe _0.20 O _3 catalysts was performed by degrading Congo red (CR) dye under visible light exposure. Substituted catalyst exhibited superior photodegradation by showing 97% degradation in comparison to pristine LaNiO _3 (63% only) in 120 min. Degradation of CR followed the pseudo fist order kinetics. In addition, the catalyst dose effect, dye concentration and pH variation was studied for Cr dye degradation. Enhanced photocatalytic activity and narrow bandgap of Ce and Fe doped LaNiO _3 introduce such materials as efficient visible active photocatalysts to be utilized in dye removal application from waste water and in photovoltaic applications, respectively.

Eucalyptus is well reputed for its use as medicinal plant around the globe. The present study was planned to evaluate chemical composition, antimicrobial and antioxidant activity of the essential oils (EOs) extracted from seven Eucalyptus species frequently found in South East Asia (Pakistan). EOs from Eucalyptus citriodora, Eucalyptus melanophloia, Eucalyptus crebra, Eucalyptus tereticornis, Eucalyptus globulus, Eucalyptus camaldulensis and Eucalyptus microtheca were extracted from leaves through hydrodistillation. The chemical composition of the EOs was determined through GC-MS-FID analysis. The study revealed presence of 31 compounds in E. citriodora and E. melanophloia, 27 compounds in E. crebra, 24 compounds in E. tereticornis, 10 compounds in E. globulus, 13 compounds in E. camaldulensis and 12 compounds in E. microtheca. 1,8-Cineole (56.5%), α-pinene (31.4%), citrinyl acetate (13.3%), eugenol (11.8%) and terpenene-4-ol (10.2%) were the highest principal components in these EOs. E. citriodora exhibited the highest antimicrobial activity against the five microbial species tested (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Aspergillus niger and Rhizopus solani). Gram positive bacteria were found more sensitive than Gram negative bacteria to all EOs. The diphenyl-1-picrylhydazyl (DPPH) radical scavenging activity and percentage inhibition of linoleic acid oxidation were highest in E. citriodora (82.1% and 83.8%, respectively) followed by E. camaldulensis (81.9% and 83.3%, respectively). The great variation in chemical composition of EOs from Eucalyptus, highlight its potential for medicinal and nutraceutical applications.

Alcalase was immobilized on glyoxyl 4% CL agarose beads. This permitted to have Alcalase preparations with 50% activity retention versus Boc-l-alanine 4-nitrophenyl ester. However, the recovered activity versus casein was under 20% at 50 °C, as it may be expected from the most likely area of the protein involved in the immobilization. The situation was different at 60 °C, where the activities of immobilized and free enzyme became similar. The chemical amination of the immobilized enzyme or the treatment of the enzyme with glutaraldehyde did not produce any significant stabilization (a factor of 2) with high costs in terms of activity. However, the modification with glutaraldehyde of the previously aminated enzyme permitted to give a jump in Alcalase stability (e.g., with most than 80% of enzyme activity retention for the modified enzyme and less than 30% for the just immobilized enzyme in stress inactivation at pH 7 or 9). This preparation could be used in the hydrolysis of casein at pH 9 even at 67 °C, retaining around 50% of the activity after 5 hydrolytic cycles when the just immobilized preparation was almost inactive after 3 cycles. The modified enzyme can be reused in hydrolysis of casein at 45 °C and pH 9 for 6 cycles (6 h) without any decrease in enzyme activity.