[en] In the present work, the fresh juice of black mulberry (Morus nigra) was tested for antimicrobial activity against various pathogenic microorganisms. Total antioxidant contents, total phenolic contents, total anthocyanins, trace minerals, total acid contents, total solids and ascorbic acid content were also evaluated. The results showed good antimicrobial activity both for Gram- positive and Gram-negative bacteria, with highest zones of inhibition for Bacillus spizizenii (19.68 mm, Gram-positive) and Pseudomonas aeruginosa (19.87 mm, Gram-negative). The black mulberry juice was rich in ascorbic acid (23.45 mg/100 g), had low overall acid content (1.60 %) and had 19% total soluble solids. The average total anthocyanins and total phenolic contents of black mulberry juice were 769 mu g/g of cyanidin 3-glucoside equivalent (Cy 3-gly) per gram and 2050 mu g of gallic acid equivalent (GAE) per gram of fresh juice. The average antioxidant activity (Trolox equivalent, TE) of fresh juice was 14.00 mu mol/g according to a FRAP assay and 20.10 mu mol/g according to a DPPH assay. The fresh juice was also rich in a variety of trace minerals. (author)

[en] Seven compounds have been isolated for the first time from the chloroform soluble fraction of Buddleja asiatica namely, buddlejone (1), dihydrobuddledin-A (2), buddledone-B (3), ursolic acid (4), 2-phenylethyl-beta-D-glucoside (5), 7-deoxy-8-epiloganic acid (6) and scutellarin-7-O-beta-D-glucopyranoside (7). Their structures have been elucidated through spectroscopic studies. All the isolated compounds were tested for their antimicrobial activity. (author)

[en] Medicinal plants have been used for centuries to prevent and treat different health disorders. Bergenia ciliata is native to Himalayas and is used traditionally as an antipyretic, an astringent, diuretic and for dissolving kidney and bladder stones. Due to the medicinal value of B. ciliata, it has been over-exploited leading to be classified an an endangered species. The current study was designed to see B. ciliata response to tissue culturing specifically to callus formation and antibacterial activity of callus extracts. Callus inducing media was supplemented with 2, 4-D and Kinetin. Visible signs of callus formation on cut edges of explants were observed after 13 and 14 days of culturing and leaf showed 95% while petiole depicted 88% callus induction, respectively. Highest dry weight of callus was obtained from petioles (0.61 mg), which was 12% higher than that of dry weight of callus produced by leaf explants on same medium. The ethanolic extract of both petiole and petiole-derived callus demonstrated promising antibacterial activity against six pathogenic bacterial strains. The results suggested that callus from valuable medicinal plants can provide a way to produce essential metabolites and help in the conservation of the natural population of endangered plants. In future, evaluating biochemical composition of callus and plants extracts will enable us to find new dimensions to get maximum benefits from in-vitro technique. (author)

[en] In the present study, an attempt has been made to collect and identify the Pteridophytes of Utror valley, Swat. During the survey 16 Pteridophytes belonging to 10 genera and 9 families are taxonomically and ethnobotanically described. Dryopteridaceae was found as a dominant family having the largest number of species, i.e. 4 species belonging to the genus Dryopteris. Aspleniaceae was the second largest family in terms of number of species, i.e. 3 species belonging to the genus Asplenium. The families like Adiantaceae, Cystopteridaceae, Dennstaedtiaceae, Polypodiaceae, and Thelypteridaceae were represented by one species each, i.e. Adiantum venustum, Cystoperis fragilis, Pteridium aquilinum, Polypodium vulgare, and Cyclosorus dentatus, respectively. The study revealed that these ferns are used by the local community for the treatment of different health ailments. (author)

[en] The aim of present paper was to evaluate clinical effectiveness of combined antimicrobial treatment by means of in vitro synergism tests and to determine effectiveness of used procedure to direct applications of these treatment strategies in patient presenting with sepsis from varied resistance bacteria. Treatment applied was assessed in 163 newborn patients presenting with sepsis from positive hemoculture in 'America Arias' University Gynecology-Obstetrics Hospital from January 1993 to December 2000, by checkerboard method in microtritate plates. In vitro synergic drug combinations showed a high probability of clinical effectiveness, independently of susceptibility pattern of microorganism event versus resistant strains to both antimicrobials used in treatment. All in vitro antagonistic results correspond both with a therapeutic clinical failure. Procedure used may be a valuable tool to direct therapeutics in patients presenting with sepsis from resistant microorganisms. (Author)

[en] The review is devoted to the latest achievements in the design of dual action antibiotics — heterodimeric (chimeric) structures based on antibacterial agents of different classes (fluoroquinolones, anthracyclines, oxazolidines, macrolides and so on). Covalent binding can make the pharmacokinetic characteristics of these molecules more predictable and improve the penetration of each component into the cell. Consequently, not only does the drug efficacy increase owing to inhibition of two targets but also the resistance to one or both antibiotics can be overcome. The theoretical grounds of elaboration, design principles and methods for the synthesis of dual action antibiotics are considered. The structures are classified according to the type of covalent spacer (cleavable or not) connecting the moieties of two agents. Dual action antibiotics with a spacer that can be cleaved in a living cell are considered as dual action prodrugs. Data on the biological action of heterodimeric compounds are presented and structure–activity relationships are analyzed. The bibliography includes 225 references

[en] Jabal Al-Akhdar (Oman) is one of diverse floral region of Arabian Peninsula. Ochradenus arabicus, is an important medicinal plant to local people of the area. However, little is known about its potential role in biological activities against various emerging ailments. The collected plant samples were extracted with methanol and fractionated into n-hexane (JOAH), ethyl acetate (JOAE), chloroform (JOAC), n-butanol (JOAB) and water (JOAAQ). Various concentrations of these fractions were tested for their antimicrobial, anticancer, antioxidant, antidiabetic, phenolics, flavonoids, allopathic and nutrition quality properties. The results showed that fruits and leaves of O. arabicus have higher levels of carbohydrate, crude fats, fibres, proteins, moisture, ash and energy values. In phytotoxic activities, JOAAQ inhibited the lettuce seed germination and growth. The anticancer activities of fractions showed that JOAE, JOAB and JOAAQ are potent to reduce the cancer cell viability of HT29, HCT116, HepG2 and MCF-7 lines with a concentration of 1000 micro g/ml. JOAB showed a meagre activity of 12% in Glucosidase inhibition assay. The total phenolic and flavonoid contents were significantly higher in JOAE, which also resulted in higher DPPH radical scavenging activity as compared to other fractions and control. JOAE also exhibited higher antibacterial and antifungal activities. The results of current findings suggest that O. arabicus is a potential medicinal plants, which could be subjected to advance column chromatography for lead compounds using a bioassay guided approach. (author)

[en] Herein, we present a new variation for an eco-friendly methodology for the synthesis of chalcogenoester in good-to-excellent yields in a short time, with an easy work-up/purification step, and in a greenest methodology, affording the minimum generation of solid and liquid waste, in comparison to that described in the literature. Additionally, some selected compounds were evaluated as antimicrobial agents, showing moderate activity against a variety of microorganisms including the K. pneumoniae, P. aeruginosa and also some selected fish pathogenic bacteria. Graphic abstract:

No abstract available

[en] Bacterial persistence (phenotypic tolerance to antibiotics) provides a prime example of bet-hedging, where normally growing cells generate slow-growing but antibiotic-tolerant persister cells to survive through periods of exposure to antibiotics. The population dynamics of persistence is explained by a phenotype switching mechanism that allows individual cells to switch between these different cellular states with different environmental sensitivities. Here, we perform a theoretical study based on an exact solution for the case of a periodic variation of the environment to address how phenotype switching emerges and under what conditions switching is or is not beneficial for long-time growth. Specifically we report a bifurcation through which a fitness maximum and minimum emerge above a threshold in the duration of exposure to the antibiotic. Only above this threshold, the optimal phenotype switching rates are adjusted to the time scales of the environment, as emphasized by previous theoretical studies, while below the threshold a non-switching population is fitter than a switching one. The bifurcation can be of different type, depending on how the phenotype switching rates are allowed to vary. If the switching rates for both directions of the switch are coupled, the transition is discontinuous and results in evolutionary hysteresis, which we confirm with a stochastic simulation. If the switching rates vary individually, a continuous transition is obtained and no hysteresis is found. We discuss how both scenarios can be linked to changes in the underlying molecular networks. (paper)