A comparative study of interaction of tetracycline with several proteins using time resolved anisotropy, phosphorescence, docking and FRET

A comparative study of the interaction of an antibiotic Tetracycline hydrochloride (TC) with two albumins, Human serum albumin (HSA) and Bovine serum albumin (BSA) along with Escherichia Coli Alkaline Phosphatase (AP) has been presented exploiting the enhanced emission and anisotropy of the bound drug. The association constant at 298 K is found to be two orders of magnitude lower in BSA/HSA compared to that in AP with number of binding site being one in each case. Fluorescence resonance energy transfer (FRET) and molecular docking studies have been employed for the systems containing HSA and BSA to find out the particular tryptophan (Trp) residue and the other residues in the proteins involved in the binding process. Rotational correlation time (θc) of the bound TC obtained from time resolved anisotropy of TC in all the protein-TC complexes has been compared to understand the binding mechanism. Low temperature (77 K) phosphorescence (LTP) spectra of Trp residues in the free proteins (HSA/BSA) and in the complexes of HSA/BSA have been used to specify the role of Trp residues in FRET and in the binding process. The results have been compared with those obtained for the complex of AP with TC. The photophysical behaviour (viz., emission maximum, quantum yield, lifetime and θc) of TC in various protic and aprotic polar solvents has been determined to address the nature of the microenvironment of TC in the protein-drug complexes

Application of natural preservatives and sweeteners in fruit products to reduce health risks - a review

The costs of food deterioration in terms of both money and health are rising. Fungi, bacteria, yeast, insects, and rodent contamination of food supplies continue to be a major public health concern. Chemical preservatives are effective but can be potentially fatal to human health in certain cases. As potent food preservatives, essential oils made from plants are a great alternative to synthetic preservatives. They also possess a variety of anti-inflammatory, antibacterial, and antioxidant effects. The use of artificial sweeteners in food products, which raises safety questions and health issues while also having reduced nutritional value, is another problem in the food industry. Because natural sweeteners are linked to a healthy lifestyle and have superior nutritional qualities, consumers today prefer them. This article goes through the issues with artificial sweeteners and preservatives and goes into great length about the many different essential oils and natural sweeteners that are much safer and healthier alternatives

Collection and evaluation of indigenous buck semen at the coastal region of Bangladesh

Evaluation of semen characteristics is an important and prior for semen preservation. The aim of this study was to collection and evaluation of indigenous buck semen in the coastal region of Bangladesh. The semen was collected from bucks through artificial vagina method. The colour, odour, volume, viscosity, mass activity, consistency, concentration and individual sperm motility were analysed and recorded after collection from pre-selected four bucks. The colour and odour of all buck (B) semen were creamy white to milky white and fishy smell, respectively. In this study, we found that the average volume of B-1, B-2, B-3 and B-4 were 0.74, 0.98, 0.42 and 0.60 ml, respectively. The average grading of viscosity of B-1, B-2, B-3 and B-4 were 3.2, 3.8, 2.6 and 3.0, respectively. The average grading of mass activity of B-1, B-2, B-3 and B-4 were 3.6, 3.2, 2.4 and 3.4, respectively. The consistency of B-1, B-2, B-3 and B-4 were 4.2, 4.8, 2.8 and 4.0, respectively. The concentration of B-1, B-2, B-3 and B-4 were 1.58, 1.94, 0.62 and 1.54 ×109 per ml of semen volume. The average percentage of individual sperm motility of B-1, B-2, B-3 and B-4 were 81, 71, 66 and 80%, respectively. Viscosity, mass activity, consistency, concentration and individual sperm motility were significantly (p < 0.05) correlate with each other. It may be concluded that the data about semen of the bucks are in acceptable level for preservation. Further study will be designed for the evaluation of viability and motility of sperm before and after freezing as liquid semen

Recent Progress on Emerging Applications of Hydrochar

Hydrothermal carbonization (HTC) is a prominent thermochemical technology that can convert high-moisture waste into a valuable product (called hydrochar) at a relatively mild treatment condition (180–260 °C and 2–10 MPa). With rapidly growing research on HTC and hydrochar in recent years, review articles addressing the current and future direction of this research are scarce. Hence, this article aims to review various emerging applications of hydrochars, e.g., from solid fuel to soil amendment, from electron storage to hydrogen storage, from dye adsorption, toxin adsorption, heavy metal adsorption to nutrient recovery, and from carbon capture to carbon sequestration, etc. This article further provides an insight in the hydrochar’s working mechanism for various applications and how the applications can be improved through chemical modification of the hydrochar. Finally, new perspectives with appropriate recommendations have been made to further unveil potential applications and its improvement through hydrochar and its modified version

Recent Progress on Emerging Applications of Hydrochar

Hydrothermal carbonization (HTC) is a prominent thermochemical technology that can convert high-moisture waste into a valuable product (called hydrochar) at a relatively mild treatment condition (180–260 °C and 2–10 MPa). With rapidly growing research on HTC and hydrochar in recent years, review articles addressing the current and future direction of this research are scarce. Hence, this article aims to review various emerging applications of hydrochars, e.g., from solid fuel to soil amendment, from electron storage to hydrogen storage, from dye adsorption, toxin adsorption, heavy metal adsorption to nutrient recovery, and from carbon capture to carbon sequestration, etc. This article further provides an insight in the hydrochar’s working mechanism for various applications and how the applications can be improved through chemical modification of the hydrochar. Finally, new perspectives with appropriate recommendations have been made to further unveil potential applications and its improvement through hydrochar and its modified version

Regional anesthesia in transurethral resection of prostate (TURP) surgery: A comparative study between saddle block and subarachnoid block

Background: Spinal anesthesia is the technique of choice in transurethral resection of prostate (TURP). The major complication of spinal technique is risk of hypotension. Saddle block paralyzed pelvic muscles and sacral nerve roots and hemodynamic derangement is less. Aims and objectives: To compare the hemodynamic changes and adequate surgical condition between saddle block and subarachnoid block for TURP. Material and methods: Ninety patients of aged between 50 to 70 years of ASA-PS I, II scheduled for TURP were randomly allocated into 2 groups of 45 in each group. Group A patients were received spinal (2 ml of hyperbaric bupivacaine) and Group B were received saddle block (2 ml of hyperbaric bupivacaine). Baseline systolic, diastolic and mean arterial pressure, heart rate, oxygen saturation were recorded and measured subsequently. The height of block was noted in both groups. Hypotension was corrected by administration of phenylephrine 50 mcg bolus and total requirement of vasopressor was noted. Complications (volume overload, TURP syndrome etc.) were noted. Results: Incidence of hypotension and vasopressor requirement was less (P < 0.01) in Gr B patients.Adequate surgical condition was achieved in both groups. There was no incidence of volume overload, TURP syndrome, and bladder perforation. Conclusion: TURP can be safely performed under saddle block without hypotension and less vasopressor requirement

Interaction of multitryptophan protein with drug: An insight into the binding mechanism and the binding domain by time resolved emission, anisotropy, phosphorescence and docking

The interaction of antibiotic Tetracycline hydrochloride (TC) with Alkaline Phosphatase (AP) from Escherichia coli, an important target enzyme in medicinal chemistry, having tryptophan (Trp) residues at 109, 220 and 268 has been studied using the steady state and time resolved emission of the protein and the enhanced emission of the bound drug. The association constant at 298 K (≈10⁶ [M]⁻¹) and the number of binding site (= 1) were estimated using the quenched Trp emission of AP, the enhanced emission and the anisotropy of the bound drug. The values of ΔH⁰ and ΔS⁰ are indicative of electrostatic and H-bonding interaction. The low temperature phosphorescence of free AP and the protein- drug complex and molecular docking comprehensively prove the specific involvement of partially exposed Trp 220 in the binding process without affecting Trp 109 and Trp 268. The Förster energy transfer (ET) efficiency and the rate constant from the Trp residue to TC = 0.51 and ≈10⁸ s⁻¹ respectively. Arg 199, Glu 219, Trp 220, Lys 223, Ala 231, Arg 232 and Tyr 234 residues are involved in the binding process. The motional restriction of TC imposed by nearby residues is reflected in the observed life time and the rotational correlation time of bound TC

Plot of φ (A) and <τ> (B) against (I) dielectric constant (ε), (II) solvent polarizability parameter (π*), (III) Hydrogen bond donating ability (α) of different solvents, (1) DMSO, (2) DMF, (3) EG, (4) EtOH, (5) i-PrOH.

<p>Plot of φ (A) and <τ> (B) against (I) dielectric constant (ε), (II) solvent polarizability parameter (π*), (III) Hydrogen bond donating ability (α) of different solvents, (1) DMSO, (2) DMF, (3) EG, (4) EtOH, (5) i-PrOH.</p