Quality Of Bacteria Research Articles

Gut Microbiota and its impact on the inflammation-dysplasia-cancer sequence

Abstract The understanding and explanation of inflammation-dysplasia-cancer sequence is challenging. The gut microbiota is an important factor for the intestine wall. The changes in bacteria quality and/or quantity (dysbiosis) may begin the colon inflammation. This paper reviewed the gut microbiome risk factors which may lead to colon cancer.

Effect of Supplementing Hydrolysable Tannins to a Grower-Finisher Diet Containing Divergent PUFA Levels on Growth Performance, Boar Taint Levels in Back Fat and Intestinal Microbiota of Entire Males.

Simple SummaryThe European pig production industry needs to adapt to societal concerns regarding animal welfare. One of these concerns is the current castration practice of male piglets, which is primarily performed to avoid boar taint. Boar taint is an unpleasant and unwanted odor and flavor that can be found in the pork of entire male pigs. The compounds skatole, indole, and androstenone are the primary causes of boar taint, which can occur during cooking when the compounds evaporate. Recently, it has been hypothesized that with increasing levels of polyunsaturated fatty acids in the adipose tissue, the concentration of boar taint compounds decreases. Furthermore, we have shown that hydrolysable tannins included in pig diets tend to reduce the level of boar taint compounds in the adipose tissue. Thus, the objective of this study was to determine whether cumulative effects on the level of boar taint can be expected when both polyunsaturated fatty acids and hydrolysable tannins rich compounds are included in the diet. In addition, special emphasis was put on their effects on the gut microbiota composition. Investigating the gut bacterial population, we observed that polyunsaturated fatty acids had no effects on gut microbiota, while hydrolysable tannins affected both the quantity and quality of bacteria in a way that could explain the observed boar taint levels.A retrospective data analysis suggested that the levels of boar taint compounds depend on the polyunsaturated fatty acid (PUFA) level of the adipose tissue (AT) being significantly greater in the unsaturated AT. In addition, we recently reported that hydrolysable tannins (HTs) offered to entire males (EMs) reduce skatole and, to a greater extent, indole levels in the AT. Thus, the objective of the study was to determine the impact of HTs and a high dietary level of PUFA on growth performance and board taint compounds in EMs. In addition, the interaction between PUFA and HTs on gut microbiota and its link to intestinal skatole and indole production was investigated. At 25 kg BW, 44 EM originating from 11 litters were randomly assigned within litter to four dietary treatments. Two basal grower (25–60 kg BW) and finisher (60–105 kg BW) diets containing either 2% soy oil (H = high PUFA level) or 2% tallow (L = low PUFA level) were formulated. The H and L diets were either supplemented (H+/L+) or not (H−/L−) with 3% chestnut extract containing 50% HTs. The pigs had ad libitum access to the diets and were slaughtered at 170 days of age. The microbiota composition was investigated through the 16S rRNA gene sequences obtained by next-generation sequencing (Illumia MiSeq platform, San Diego, CA, USA) and analyzed with a specific packages in R, version 3.5.0. Regardless of the PUFA content, the EMs fed the H+ diets were 2% (p < 0.01) less feed efficient overall. This was due to the slower (p = 0.01) growth in the finisher period despite similar feed intake. Carcass characteristics were not affected by the diets. Regardless of HT feeding, the PUFA level in the AT of the H pigs was 10% greater (p = 0.05) than in the L pigs. The indole level tended (p = 0.08) to be 50% lower in the H+ group. Surprisingly, the pigs that were fed diet H− had greater skatole levels than those fed diet L−, with intermediate skatole levels in the H+ and L+. Independent of the PUFA level, the HTs decreased bacteria abundance and qualitatively affected the microbiota composition. In conclusion, these data do not confirm that boar taint compound levels were related to PUFA levels in the AT. However, HTs can be considered to be a promising alternative to conventional antibacterial additives, with no detrimental effects on pig gut health and with appealing properties for reducing the synthesis of the main components of boar taint.

Investigation of feeding behaviour in C. elegans reveals distinct pharmacological and antibacterial effects of nicotine

Caenorhabditis elegans is an informative model to study the neural basis of feeding. A useful paradigm is one in which adult nematodes feed on a bacterial lawn which has been pre-loaded with pharmacological agents and the effect on pharyngeal pumping rate scored. A crucial aspect of this assay is the availability of good quality bacteria to stimulate pumping to maximal levels. A potential confound is the possibility that the pharmacological agent impacts bacterial viability and indirectly influences feeding rate. Here, the actions of nicotine on pharyngeal pumping of C. elegans and on the Escherichia coli bacterial food source were investigated. Nicotine caused an immediate and concentration-dependent inhibition of C. elegans pharyngeal pumping, IC50 4 mM (95% CI = 3.4 mM to 4.8 mM). At concentrations between 5 and 25 mM, nicotine also affected the growth and viability of E. coli lawns. To test whether this food depletion by nicotine caused the reduced pumping, we modified the experimental paradigm. We investigated pharyngeal pumping stimulated by 10 mM 5-HT, a food ‘mimic’, before testing if nicotine still inhibited this behaviour. The IC50 for nicotine in these assays was 2.9 mM (95% CI = 3.1 mM to 5.1 mM) indicating the depletion of food lawn does not underpin the potency of nicotine at inhibiting feeding. These studies show that the inhibitory effect of nicotine on C. elegans pharyngeal pumping is mediated by a direct effect rather than by its poorly reported bactericidal actions.

Spatial and temporal variability of saprophytic and water quality bacteria along the coast of the Aqaba and Suez Gulfs and Red Sea, Egypt

Spatial and temporal variability of saprophytic (SB) and salt-tolerant saprophytic (STSB) bacterial counts as well total coliforms (TC), Escherichia coli (EC) and faecal streptococci (FS) were investigated in the Egyptian surface coastal waters of the Aqaba and Suez Gulfs as well as the Red Sea. A total of 200 samples was collected from 40 sites during January, March, May, July and September 2002. Hydrographical parameters including water temperature (C), salinity (S ‰ ), dissolved oxygen (DO) and pH were also measured. According to the European and Egyptian current standards, of 200 samples analysed during 2002, 183 samples (91.5%) were acceptable for marine recreational purposes. The results indicated that the water quality of the investigated coastal areas was generally affected by sewage disposal and/or other anthropogenic influences. However, in bathing and recreational areas, the water quality was mainly affected by the excessive human presence, i.e. tourists/visitors and their recreational activities. In general, the counts of all investigated bacterial groups were found to be correlated with each other. Key words: Red Seat, Aqaba Gulf, Suez Gulf, recreational waters, water quality, bacterial indicators, saprophytic bacteria

Spatial and temporal variability of saprophytic and water quality bacteria along the coast of the Aqaba and Suez Gulfs and Red Sea, Egypt

Spatial and temporal variability of saprophytic and water quality bacteria along the coast of the Aqaba and Suez Gulfs and Red Sea, Egypt

Treatment Efficiency and Filtration Rate of a Horizontal Sand Filtration System

The purpose of this study was to establish acceptable criteria for a horizontal sand filtration (HSF) system that are suitable for the design of community water supply units in rural areas. Two laboratory scales of HSF were constructed and tested for their filtration rates and treatment efficiency in Visetchaicharn District of Angthong Province, Thailand. The main structure of both models was the same except for the lengths of the filtration column, i.e., 80 cm. in Model 1 and 100 cm. in Model 2. The results of treatment efficiency of both models were very satisfactory. The physical and chemical quality of the filtered water was within the standards for drinking water except for bacteria quality. The rates of filtration of Model 1 were slightly faster than those of Model 2 for both one and two meters of water level in the raw water column. The rates for both models were higher than the lower limit standards of the slow sand filtration system throughout the study.