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Anionic antimicrobial peptides (AAMPs) with net charges ranging from -1 to -8 have been identified in frogs, toads, newts and salamanders across Africa, South America and China. Most of these peptides show antibacterial activity and a number of them are multifunctional, variously showing antifungal activity, anticancer action, neuropeptide function and the ability to potentiate conventional antibiotics. Antimicrobial mechanisms proposed for these AAMPs, include toroidal pore formation and the Shai-Huang-Matsazuki model of membrane interaction along with pH dependent amyloidogenesis and membranolysis via tilted peptide formation. The potential for therapeutic and biotechnical application of these AAMPs has been demonstrated, including the development of amyloid-based nanomaterials and antiviral agents. It is concluded that amphibian AAMPs represent an untapped potential source of biologically active agents and merit far greater research interest., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Strict regulations are forcing dyeing factory to upgrade existing waste treatment system. In this study, advanced treatment of dyeing secondary effluent by magnetic anion exchange resin (NDMP) was investigated and compared with ultrafiltration (UF); NDMP as a pre-treatment of reverse osmosis (RO) was also studied. NDMP resin (20 mL/L) gave higher removal of dissolved organic carbon (DOC) (83.9%) and colority (94.9%) than UF with a cut-off of 10 kDa (only 48.6% and 44.1%, respectively), showing that NDMP treatment was effective to meet the stringent discharge limit of DOC and colority. Besides, NDMP resin (20 mL/L) as a pretreatment of RO increased the permeate flux by 12.5% and reduced irreversible membrane fouling by 6.6%, but UF pretreatment did not mitigate RO membrane fouling. The results of excitation-emission matrix fluorescence spectra and resin fractions showed that NDMP had more efficient removal than UF for transphilic acid and hydrophilic fraction, such as protein-like organic matters and soluble microbial products, which contributed to a significant proportion of RO membrane fouling. In sum, NDMP resin treatment not only gave effective removal of DOC and colority of dyeing secondary effluent, but exhibited some improvement for RO membrane flux and irreversible fouling., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Marine sediments from Lianshan Bay in Huludao, China, were studied in laboratory. A series of simulated experiments were carried out to investigate the influences of three kinds of anions Cl-, SO42- and HCO3 on the release of Cd, Pb, Cu and Zn from the sediments. The results showed that the sequences about the impact of the three anions were Cl- >HCO3 > SO42. The release potential of heavy metals in the presence of each anions was in the following order: Cd>>Cu>Zn approximately equal to Pb. The correlations were positive between Cl content and the quantity of Cd released from the marine sediment, whereas there was no significant relationship between Cl-content and amount of Cu and Zn released. For SO42- and HCO3-, the release of the heavy metals from marine sediments was not obvious.