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Resistance to antibiotics is one of the most critical health problems in the world. Therefore, finding new treatment methods to be used as alternatives to antibiotics has become a priority for researchers. Similar to phages, certain products containing antimicrobial components, such as molasses, are widely used to eliminate resistant bacteria. Molasses has a strong antimicrobial effect on bacterial cells, and this effect is thought to be due to the breakdown of the cytoplasmic cell membrane and cell proteins of the polyphenols in molasses. In the present study, phage–molasses interactions were investigated to examine the effects of concomitant use. It was found that molasses samples increased the size of phage plaques by up to 3-fold, and MIC and 1/2 x MIC concentrations of molasses increased the burst size of phages. Although no synergistic effect was found between the phage and molasses, the antimicrobial activities of the components and the effect of molasses on phage activity were demonstrated. © 2022, Canadian Science Publishing. All rights reserved. Emine Ku€bra Tayyarcan is supported by the 100/ 2000 doctoral scholarship provided by the Council of Higher Education, Turkey.

Decentralized wastewater treatment systems enable wastewater to be treated at the source for cleaner discharge into the environment, protecting public health while allowing for reuse for agricultural and other purposes. This study, conducted in Thailand, investigated a decentralized wastewater treatment system incorporating a physical and photochemical process. Domestic wastewater from a university campus and conventional septic tank effluent from a small community were filtered through a woven-fiber microfiltration (WFMF) membrane as pretreatment for ultraviolet (UV) disinfection. In domestic wastewater, WFMF reduced TSS (by 79.8%), turbidity (76.5%), COD (38.5%), and NO3 (41.4%), meeting Thailand irrigation standards for every parameter except BOD. In septic tank effluent, it did not meet Thailand irrigation standards, but reduced TSS (by 77.9%), COD (37.6%), and TKN (13.5%). Bacteria (total coliform and Escherichia coli) and viruses (MS2 bacteriophage) passing through the membrane were disinfected by flow-through UV reactors containing either a low-pressure mercury lamp or light-emitting diodes (LEDs) emitting an average peak wavelength of 276 nm. Despite challenging and variable water quality conditions (2% &lt, UVT &lt, 88%), disinfection was predictable across water types and flow rates for both UV sources using combined variable modeling, which enabled us to estimate log inactivation of other microorganisms. Following UV disinfection, wastewater quality met the WHO standards for unrestricted irrigation.

Feeding of infant formula using contaminated bottles may be an important transmission pathway of enteric pathogens during early life. Determinants of suboptimal bottle hygiene and the feasibility and acceptability of intervention strategies have not been well assessed. We evaluated the extent of bottle contamination, its contributing factors, and options for promoting improved bottle hygiene in a Peruvian shantytown. During Phase 1, we sampled from bottles and caregiver hands (n = 48) and processed for enumeration of total coliform and Escherichia coli colony-forming units. A semi-structured questionnaire captured bottle use and hygiene practices. Phase 2 involved the identification of candidate practices to recommend to caregivers. Phase 3 consisted of a behavioral trial in which 14 caregivers were educated about improved practices for bottle disinfection and later reported on their experiences implementing them. Fecal bacteria were detected in 43.8% of bottles sampled during Phase 1 and in 21.7% of hands. Caregivers overall did not use effective methods for disinfecting bottles, displayed misunderstandings surrounding hygienic practices, and few had ever discussed bottle hygiene with a health provider. Findings from the behavioral trial indicated that the improved practice of brushing the bottle with dish detergent for 30 seconds after every use is preferable to boiling the bottle for several minutes daily as caregivers reported that the brush was simple to use, efficient, and practical. The promotion of a bottle brush and detergent is a feasible and acceptable intervention strategy in peri-urban settings, and future research should evaluate its long-term effectiveness for reducing bottle contamination.

The efficiency of ultraviolet (UV) disinfection and the regrowth potential of total coliforms were investigated in humic waters. Experiments were conducted according to an experimental design in which a UV radiation dose range of 68-681 mW s/cm(2) was applied to waters containing various concentrations (0-10 mg/L) of fulvic acid. Experimental results strongly suggested that the harmful effect of UV radiation on bacteria was diminished in humic waters due to absorption of UV light. Increasing concentrations of fulvic acid appeared to enhance its influence with elevated doses of UV radiation. Measured inactivation responses were on the order of 1-6 log(10) units for the UV dose range used. Comparison of k (inactivation coefficient) values for nonhumic water to highly humic water indicated that k decreased proportionally as the fulvic acid concentration of water was increased. The results of dark-incubation tests indicated significant regrowth of bacteria in fulvic acid-containing waters.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:20:57Z No. of bitstreams: 0 Made available in DSpace on 2014-05-27T11:20:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-12-01 Objective. To assess the potential for contamination of wastewaters from pig farming. Methods. Wastewaters from pig farming were stored in a tank. After 0, 30, 60, 90, and 120 days of hydraulic retention, they were added to lysimeters filled with argillaceous, sandy, or medium soil. Finally, these lysimeters were submitted to simulations of either a rainy season or a dry season. The number of colony-forming units (CFUs) of total coliforms, fecal coliforms, and fecal streptococci was measured in the effluents of the storage tank (for the various periods of hydraulic retention), in the percolate from the lysimeters, and in the three types of soil. The microbiological analyses were carried out using the membrane filter technique. The pH analyses were done potentiometrically. Results. For the three microorganisms, the largest decrease in bacterial counts in the storage tanks occurred with 90 or 120 days of retention. There was a marked decrease in the bacterial count in the percolates of the three soils. For the three soil types the greatest reduction in bacterial counts was found in medium soil, due to its acidity (pH < 7.0). Hydraulic retention was not sufficient to ensure the sanitary adequacy of the wastewaters and their use for irrigation, given that fecal coliform values were above 1 000 CFU per 100 mL. Therefore, adding the residues to the soil was considered a second stage of treatment. Conclusions. The retention of wastewaters followed by adding them to soil was effective in minimizing the contaminating effect of pig farming residues. The storage time for wastewaters from pig farming could be decreased from 120 to 90 days. UNESP Fac. de Cie. Agrarias e Veterinarias Depto. Med. Vet. Prev./Repro. Anim., Jaboticabal, SP Depto. Med. Vet. Prev./Repro. Anim. Fac. de Cie. Agrarias e Veterinarias UNESP, V. Acesso. P. P. D. Castellane, km 5, CEP 14884-9000, Jaboticabal, SP UNESP Fac. de Cie. Agrarias e Veterinarias Departamento de Engenharia Rural, Jaboticabal, SP UNESP Fac. de Cie. Agrarias e Veterinarias Depto. Med. Vet. Prev./Repro. Anim., Jaboticabal, SP Depto. Med. Vet. Prev./Repro. Anim. Fac. de Cie. Agrarias e Veterinarias UNESP, V. Acesso. P. P. D. Castellane, km 5, CEP 14884-9000, Jaboticabal, SP UNESP Fac. de Cie. Agrarias e Veterinarias Departamento de Engenharia Rural, Jaboticabal, SP