Letters in Applied Microbiology

Significance and Impact of the Study: This study demonstrates that yeasts isolated from the ruminal fluid of dairy cattle can utilize lactic acid as a carbon and energy source for growth. The isolated yeasts can be used as probiotic supplements for dairy cattle that are fed highly concentrated diets to reduce ruminal lactic acid production.

Significance and Impact of the Study: An antibacterial peptide, named Brucin with specificity for Streptococcus pyogenes, was produced in vitro from dried fruit protein of Brucea javanica (L.) Merr. by pepsin-catalysed hydrolysis. Its inhibitory activity towards the Gram-negative bacteria was higher than penicillin G and chloramphenicol. The result suggested that Brucin may be applied for the treatment of the disease caused by Strep. pyogenes.

Significance and Impact of the Study: Two culture conditions (agar or broth) and two sample preparation methods (intact cell or protein extraction) were evaluated for their effects on profiling of Staphylococcus aureus using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Results indicated that MALDI-enabled profiling of S. aureus is most effective when cultures are grown in broth and processed using a protein extraction-based approach. These findings should enhance future efforts to maximize the performance of this approach to characterize strains of S. aureus.

Significance and Impact of the Study: The effectiveness of hydroxyaldimines for inhibition of Cryptococcus spp. growth and their low toxicity against healthy monkey kidney epithelial cells makes them promising lead compounds for the design of new anticryptococcal agents.

Significance and Impact of the Study: The use of fungus-impregnated cotton cloths is a promising point source application method for the control of adult Aedes aegypti, and this strategy could be incorporated into an integrated vector management programme aiming to reduce the incidence of dengue fever.

Significance and Impact of the Study: This is the first report of an investigation into the effect of Bacillus starter cultures on the flavour features of Moutai-flavour liquor, which verified that Bacillus licheniformis can enhance aroma concentration in Moutai-flavour liquor. Bacillus starter culture brought C₄ compounds, pyrazines, volatile acids, aromatic and phenolic compounds to the liquor, which gave a better result in sensory appraisals.

Significance and Impact of the Study: Nowadays, production of biodiesel is based on plant oils, animal fats, algal oils and microbial oils. Lipid mostly consists of triacylglycerols (TAG), and conversion of these lipids into fatty acid short-chain alcohol esters (methanol or ethanol) is the final step in biodiesel production. In this study, an oil-producing Streptomyces strain was isolated from sheep faeces. The oil was composed of C₁₄-C₁₆ long-chain fatty acid methyl esters, triglycerides and monoglycerides. This is the first isolated strain-producing biodiesel (FAME) directly from starch. Due to showing cellulase and xylanase activities, the strain would be helpful for converting renewable lignocellulose into biodiesel directly.

Significance and Impact of the Study: This study established the efficacy of the dual fluorescence method in evaluating the viability of cyanobacteria under chill-light stress. The results provided the direct evidence for acquired chill-light tolerance and the viability of overwintering Microcystis colonies. Such information can be useful in prediction of cyanobacterial blooms.

Significance and Impact of the Study: Many bacterial causes of healthcare infection can survive in the inanimate environment for lengthy periods and be transmitted to patients. Furthermore, current methods of environmental decontamination such as detergents, chemical disinfectants or gaseous fumigation are suboptimal for a variety of reasons. We assessed the efficacy of helium and helium–air plasma as a decontaminant and demonstrated a significant reduction in bacterial counts of Staphylococcus aureus on a glass surface. Atomic force microscopy morphologically confirmed the impact on bacterial cells. This approach warrants further study as an alternative to current options for hospital hygiene.

Significance and Impact of the Study: Lactobacillus plantarum AN6 was isolated from aji-narezushi. Cholesterol-lowering activity of AN6 was higher than ones of the type strain. Cell surface of AN6 was rough. FT-IR analysis indicated that the content of cell wall polysaccharides of AN6 is higher than ones in the type strain. These results indicate that AN6 can be used as a new profitable starter and probiotic.

Significance and Impact of the Study: In this study, the effect of prometryn and acetochlor on the physiology and metabolic activities of the AM fungus Glomus etunicatum were investigated. Our findings demonstrate for the first time, the impact of the two herbicides at three concentrations (0·1, 1 and 10 mg l⁻¹) on transformed carrot hairy roots/AM fungus association under strict in vitro culture conditions, which may guide the application of the two herbicides in modern agriculture.

Significance and Impact of the Study: This study is the first report of an increased efficacy of the mosquitocidal bioinsecticide Bacillus thuringiensis subsp. israelensis (Bti) when produced with a chemical insecticide. The results clearly demonstrate that deltamethrin is able to synergize the insecticidal activity of Bti through inclusion into spore membranes, reducing off-target and nonspecific toxicity occurring when the chemical is used alone as sprays. This new composite chemical–biological insecticide can become an invaluable tool as an intermediate between single chemical usage and the widespread use of Bti, notably in developing countries with limited financial resources for intensive mosquito control campaigns.

Significance and Impact of the Study: This study is the first report of detection of cpe and cpb2 toxin genes in Clostridium perfringens isolated from chicken meats in Turkey. The multiplex PCR protocol described in this study is useful for rapid detection of Clostridium perfringens toxin genes simultaneously in one-step PCR.

Significance and Impact of the Study: KB2194-320, a combination of two bacterial strains bred by spaceflight mutation, exhibited significantly improved 2-KLG productivity and hence could potentially increase the efficiency and reduce the cost of vitamin C production by the two-step fermentation process. In addition, a new pH indicator method was applied for rational screening of K2, which dramatically improved the efficiency of screening.

Significance and Impact of the Study: A biocatalyst capable of degrading a wide range of organophosphate (OP) insecticides was generated by expressing an organophosphate degradation gene in Pseudomonas sp. Ind01 involved in mineralization of acephate. The biocatalyst can be used to eliminate a wide range of OP insecticide residues from the environment.

Significance and Impact of the Study: In this study, we have shown that encapsulating silver (as the ion Ag⁺) and tea tree oil (singly and in combination) in a controlled release liposomal carrier system can improve their antimicrobial efficacy as well as reduce the effective concentration required. These findings may impact on the problems of agent toxicity caused by the need for high effective doses or microbial resistance where long term application is required.

Significance and Impact of the Study: After screening 1400 kimchi bacterial isolates, strain Lactobacillus plantarum YML007 was selected with strong antifungal activity against various foodborne pathogens. From the preliminary studies, it was found that the bioactive compound is a low molecular weight novel protein of 1256·617 Da. Biopreservative potential of Lact. plantarum YML007 was demonstrated on soybean grains, and the results point out YML007 as a potent biopreservative having broad antimicrobial activity against various foodborne pathogens.

Significance and Impact of the Study: Isomalto-oligosaccharides (IMO) are applied as functional food ingredients, but the composition and biological functionality of current commercial products are poorly documented. This study is the first to analyse IMO metabolism by Lactobacillus reuteri. Bifidobacteria were used for comparison. Commercial IMO contained IMO with degree of polymerization (DP) of up to four and panose-series oligosaccharides with DP of up to 5. L. reuteri preferentially metabolized short-chain oligosaccharides, whereas bifidobacteria preferentially metabolized higher oligosaccharides. Results of this study allow the modification of the biological and technological functionality of commercial IMO by adjustment of the degree of polymerization and will thus facilitate the application development for IMO.

Significance and Impact of the Study: Coliphages DT1 and DT6, isolated from faeces and selected on the basis of their host range, showed to be valuable tools for the control of pathogenic Escherichia coli during milk fermentation, without compromising the starter culture performance. Both phages, either individually or as a cocktail, may function as an extra safety barrier beyond traditional pasteurization, effectively reducing O157:H7 Shiga toxin-producing Escherichia coli (STEC) counts during early growth, thus avoiding Shiga toxin production and accumulation.

Significance and Impact of the Study: Food safety is especially important for children, but only limited information is available about the microbiological quality of cheap and junk foods that are consumed frequently by primary schoolchildren (e.g. dried cakes, candies and chocolates). The present study investigated the microbial quality of cheap and junk foods, and our results indicate that these foods are a potential health risk for children, therefore, deeper concern about the safety of these foods and effective countermeasures should be established to improve their microbiological safety. The present study may contribute to the development of an appropriate child food safety management system.

Significance and Impact of the Study: This manuscript describes the expression and characterization of a superoxide dismutase (SOD) from Thermus filiformis with thermophilic and cambialistic characteristics. The SODs are among the most potent antioxidants known in nature, and their stability and pharmacokinetics can vary widely in accordance to their biological source. Although the currently clinical research work has been focused on human and bovine SODs, alternative sources may become more biotechnological attractive in the near future. Our study brings new insights for the research field of antioxidant enzymes with potential application on pharmaceutical, cosmetics and food formulations.

Significance and Impact of the Study: In this study, we expressed and purified the capsid protein VP2 of GPV and developed a VP2-based i-ELISA for the detection of GPV antibodies. This i-ELISA can be used for evaluating the immune effects of GPV vaccine and for diagnosing of GPV infection.

Significance and Impact of the Study: Biomphalaria glabrata is a Brazilian freshwater Planorbidae of great medical relevance as an intermediate host of Schistosoma mansoni. About a month after being infected by one or more miracidia larvae of a compatible schistosome, B. glabrata sheds thousands of cercariae into the water where they seek human skin and, if successful, penetrate to establish infection, eventually taking up residence and maturing in blood vessels of the small intestine. Results obtained from this study aim at targeting novel biological control strategies for schistosomiasis such as paratransgenesis. This is the first study on the microbiota of B. glabrata from Brazil.