Abstract: The necessity for cellular regulation of DNA led to the development of metallonucleases to catalyze and repair DNA strand breaks. Due to cationic character, three-dimensional structural profiles, and propensity for performing hydrolysis, redox, or photoreactions of metal ions and complexes, have a natural ability for interacting with DNA. Since binding and cleavage of DNA is at the heart of cellular transcription and translation, it is an obvious target for therapeutic intervention and the development of diagnostic structural probes. Inorganic constructs such as cisplatin and its analogs exercise antitumor activity by inner-sphere coordination to DNA. During the last decades, the continuous evolution of artificial metallonucleases and metal-based chemotherapeutics such as cisplatin, photo-active octahedral metal complexes have been successfully used as DNA luminescent probes and light-driven reactive agents during the last decades. A recent emerging trend to improve their potential as molecular tools for studies of the genetic material is the design of bifunctional assemblies where the photo-active metal centre is tethered through a flexible linker to a nucleic acid recognition or reactive moiety. In this view, new metal complexes have been designed that utilize or create open coordination positions for DNA binding and hydrolysis, generate reactive oxygen containing species or other radicals for DNA oxidation, or perform direct redox reactions with DNA. This review briefly covers the aspects of drug molecule interaction factors, modes of DNA binding via groove binders, intercalators and alkylators along with the cleavage patterns such as hydrolytic, oxidative and photoinduced DNA cleavage, taking an example of Cisplatin and its mechanism.

Abstract: Ethno-gynecology means the medical practices for the treatment of Santals for their healthcare needs. The present paper documented 35 medicinal plants of Joypurhat district, Bangladesh belonging to 33 genera and 27 families were used by the local health healers for the treatment of gynecological diseases. Of these, Magnoliopsida (Dicots) is represented by 30 species under 28 genera and 22 families while Liliopsida (Monocots) is represented by 5 species under 5 genera and 5 families. Habit analysis shows that herbs, shrubs, climbers and trees are represented by 13, 4, 4 and 14 species, respectively. The medicinal plants used by the traditional users of Joypurhat district are arranged alphabetically followed by botanical name, local name, family, parts used and medicinal uses.

Abstract: Relying on modern methods of separation, strict quality control, advanced technology and optimal manufacturing process, supercritical carbon dioxide (SC-CO₂) is considered to offer an opportunity to efficiently and economically improve recovery and reproducibility of natural product in its pure form. Three-level Box–Behnken factorial design (BBD) from response surface methodology (RSM) was applied to optimize the main extraction conditions including pressure, temperature and extraction time. The three different levels of Pressure, temperature and time are between 100-250 bar, 40-60°C and 5-15 hrs respectively. The optimum conditions were found to be 350 bar, 60°C and 15 hrs. Under the optimum conditions, total phenolic content obtained was 152 mg GAE/total extract, which well agreed with the predicted yield. HPLC analysis was carried out for the optimum conditions for the identification and quantification of the phenolic compounds.

Abstract: This study focused on the production of antibacterial compound against human-pathogenic bacteria. Alkaloid and Phenols extract prepared with selected concentrations from Piper nigrum (fruits) to screening for antibacterial activity against four Gram-positive of Staphylococcus aureus and Streptococcus spp. strains with four Gram-negative of Escherichia coli strains bacteria. The antibacterial activities of the extracts (0.002, 0.004, 0.02, 0.04, 0.2, and 0.4%) were evaluated using agar diffusion methods. The completely randomized design (CRD) was used with three replications. The analysis of the alkaloid and phenol were made by fast liquid chromatography (FLC). The result showed antimicrobial activity against all tested bacteria with zone of inhibition ranged from (1-60mm). Alkaloids showed Maximum zone of inhibition against Gram negative bacteria Escherichia coli(PBR 322 standard strain) (26.4 mm) and minimum against Gram positive bacteria Staphylococcus aureus isolated from Urinary tract infection (10.5 mm). While Phenols showed maximum antibacterial activity towards Gram positive bacteria Staphylococcus aureus (isolated form Dermal infection) (22.4 mm) and least effect against Gram negative bacteria Escherichia coli (PBR 322 standard strain) (13.4 mm). Also the results showed maximum concentration activity was 0.4% which recorded for Alkaloids and Phenols (43.7 and 48.1 mm) respectively, while the minimum concentration activity was 0.002% recorded ( 0.6 and 1 mm) respectively. Beside FLC analysis results showed two alkaloid with ten phenolic compounds in P. nigrum crude extracts. The crude extract of P. nigrum demonstrated a significant antibacterial activity against the microorganisms investigated and could be used as antibacterial agents.

Abstract: This paper presents lead bioextraction using mixed cultures of Acidithiobacillus Ferrooxidans (ATF) and Acidithiobacillus Thiooxidans (ATT) on galena. The effect of leaching time at constant leaching temperature and ore mass-input were investigated. X-ray diffractometry (XRD) analysis of the galena used was carried out to evaluate the phases in the ore. Scanning electron microscopy (SEM) was carried out on reaction residues generated at different leaching times. The XRD analysis of the ore shows that it was composed of phases such as PbS, ZnS, ZnO and Cu64O with PbS dominating. The results of the experiment indicate that the concentrations of extracted lead increases with increase in the leaching time which ranged from 70 - 420 hrs. SEM of reaction residues show in some cases slight slimy substances suspected to be secretion from the microbes. A multivariate empirical model was derived, validated and used for the factorial analysis of extracted lead. The validity of the derived model expressed as; ξ - 0.258 = 0.0162 ɤ + 0.0002ϑ - 0.001₰ was rooted on the core model expression ξ - 0.258 = 0.0162 ɤ + 0.0002ϑ - 0.001₰ where both sides of the expression are correspondingly approximately equal. Regression model was used to generate results, and its trend of distribution was compared with that from experiment and derived model as means of verifying its validity. The results associating this verification translated into very close alignment of curves and significantly similar trend of data point’s distribution for experimental (ExD), derived model (MoD) and regression model-predicted (ReG) results. Evaluations from generated results indicated that extracted lead concentration per unit leaching time and final solution pH as obtained from experiment, derived model & regression model were 0.0171, 0.0162 & 0.0190 g/dm³ hr^-1 and 6.386, 6.0467 & 7.1083 respectively. The standard errors in predicting the extracted lead concentrations for each values of the leaching times and final solution pHs as obtained from experiments, derived model & regression model-predicted results were 0.3666, 0.0003 & 6.901 x 10^-5 and 1.7626, 1.3135 & 1.5437 respectively. The model operates with a confidence and reliability level range: 91-99.86 % at recorded deviation range: 0.14 - 8.51 (of the model-predicted extracted lead concentration from experimental results).