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Bread is one of the main foods which is consumed by people, especially in developing and underdeveloped countries. However, bread loses its freshness during a short storage period, and that is an important concern for bakery producers. The loss of bread freshness is mainly due to the staling and microbial contamination. Regarding the importance of bread in the diet of people all over the world, finding suitable solution to increase its shelf life is necessary. Generally, three aspects are needed to prolong the shelf life of bread and bakery products: i) preventing moisture migration from the product by using appropriate packaging; ii) controlling the formulation and process parameters to minimize the staling rate; and iii) controlling the conditions for minimal microbial growth. In this paper, some methods to increase the microbial shelf life of bread and bakery products are addressed. [ABSTRACT FROM AUTHOR]

Ceramic materials have a very long tradition of use in construction. Their durability is related to the surface of the material and the action of the corrosive environment. One of the corrosive factors acting on ceramic materials is microorganisms. They can contribute to the deterioration of the technical and performance properties of building materials. Aesthetic, physical, and chemical deterioration are considered to be the main destructive processes in ceramic materials. This work shows how the different types of the most commonly used ceramic materials, i.e., brick and tiles, are damaged. Each of these types is susceptible to microbial growth. Most microorganisms that occur on ceramic materials produce staining substances and thus form coloured biofilms. The direct action of metabolic products secreted by organisms on inorganic substrates is the main cause of chemical biodeterioration. Therefore, this work presents the impact of microorganisms on ceramic building materials. [ABSTRACT FROM AUTHOR]

This investigation seeks to determine the antibiotic-producing potential of bacteria in inhibiting the growth of other organisms like Staphylococcus aureus and Escherichia coli. The bacterial isolates were identified using standard cultural, morphological, and biochemical characterization. These were further screened for their antibiotic-producing potential using the Mueller Hinton agar (MHA) media. The identified bacterial isolates had a mean viable count ranging between 1.38×106/1,380,000 cfu/ml and 1.52×106/1,520,000 cfu/ml. Micrococcus roseus, Brevibacterium species, Bacillus subtilis, Bacillus anthracis, and Bacillus cereus were the predominant bacterial isolates. Nonetheless, the antibiotic test revealed that Bacillus subtilis and Bacillus anthracis showed antimicrobial activity against S. aureus, whereas Bacillus anthracis, Bacillus cereus, and Bacillus subtilis showed zones of inhibition against E. coli. This study shows that Bacillus species have the potential to produce antibiotics and can be used to control microbial growth in the future. [ABSTRACT FROM AUTHOR]

In the modern era of Aquaculture, biofloc technology (BFT) systems have attained crucial attention. This technology is used to reduce water renewal with the removal of nitrogen and to provide additional feed. In BFT, microorganisms play a crucial role due to their complex metabolic properties. Pathogens can be controlled through multiple mechanisms using probiotics, which can promote host development and enhance the quality of the culture environment. During culturing in a biofloc technology system, the supplementation of microalgae and its accompanying bacteria plays a beneficial role in reducing nitrogenous compounds. This enhances water quality and creates favorable environmental conditions for specific bacterial groups, while simultaneously reducing the dependency on carbon sources with higher content. The fluctuations in the bacterial communities of the intestine are closely associated with the severity of diseases related to shrimp and are used to evaluate the health status of shrimp. Overall, we will review the microbes associated with shrimp culture in BFT and their effects on shrimp growth. We will also examine the microbial impacts on the growth performance of L. vannamei in BFT, as well as the close relationship between probiotics and the intestinal microbes of L. vannamei. [ABSTRACT FROM AUTHOR]

Plant‐systemic neonicotinoid (NN) insecticides can exert non‐target impacts on organisms like beneficial insects and soil microbes. NNs can affect plant microbiomes, but we know little about their effects on microbial communities that mediate plant‐insect interactions, including nectar‐inhabiting microbes (NIMs). Here we employed two approaches to assess the impacts of NN exposure on several NIM taxa. First, we assayed the in vitro effects of six NN compounds on NIM growth using plate assays. Second, we inoculated a standardised NIM community into the nectar of NN‐treated canola (Brassica napus) and assessed microbial survival and growth after 24 h. With few exceptions, in vitro NN exposure tended to decrease bacterial growth metrics. However, the magnitude of the decrease and the NN concentrations at which effects were observed varied substantially across bacteria. Yeasts showed no consistent in vitro response to NNs. In nectar, we saw no effects of NN treatment on NIM community metrics. Rather, NIM abundance and diversity responded to inherent plant qualities like nectar volume. In conclusion, we found no evidence that NIMs respond to field‐relevant NN levels in nectar within 24 h, but our study suggests that context, specifically assay methods, time and plant traits, is important in assaying the effects of NNs on microbial communities. [ABSTRACT FROM AUTHOR]

Laticifers – among the most common defensive reservoirs in plants – are hypothesized to benefit plant fitness by preventing microbes from entering wounds. I argue that while latex seals wounds, and can suppress microbial growth, direct evidence that these processes benefit plant fitness is scarce. I outline a roadmap for filling this knowledge gap. [ABSTRACT FROM AUTHOR]

Microfluidic systems have fundamentally transformed the realm of adaptive laboratory evolution (ALE) for microorganisms by offering unparalleled control over environmental conditions, thereby optimizing mutant generation and desired trait selection. This review summarizes the substantial influence of microfluidic technologies and their design paradigms on microbial adaptation, with a primary focus on leveraging spatial stressor concentration gradients to enhance microbial growth in challenging environments. Specifically, microfluidic platforms tailored for scaled-down ALE processes not only enable highly autonomous and precise setups but also incorporate novel functionalities. These capabilities encompass fostering the growth of biofilms alongside planktonic cells, refining selection gradient profiles, and simulating adaptation dynamics akin to natural habitats. The integration of these aspects enables shaping phenotypes under pressure, presenting an unprecedented avenue for developing robust, stress-resistant strains, a feat not easily attainable using conventional ALE setups. The versatility of these microfluidic systems is not limited to fundamental research but also offers promising applications in various areas of stress resistance. As microfluidic technologies continue to evolve and merge with cutting-edge methodologies, they possess the potential not only to redefine the landscape of microbial adaptation studies but also to expedite advancements in various biotechnological areas. Key points: • Microfluidics enable precise microbial adaptation in controlled gradients. • Microfluidic ALE offers insights into stress resistance and distinguishes between resistance and persistence. • Integration of adaptation-influencing factors in microfluidic setups facilitates efficient generation of stress-resistant strains. [ABSTRACT FROM AUTHOR]

The application of nitrogen-fixing microorganisms has shown benefits in plant nutrition. This research aimed to evaluate the effect of the application of nitrogen-fixing microorganisms on the growth of corn (Zea mays L.) crops. The experiment used a randomized complete block design (RCDB), with three repetitions. The treatments applied were: T1 - Paenibacillus polymyxa 2 L ha-1; T2 - P. polymyxa 3 L ha-1; T3 - P. polymyxa 4 L ha-1; T4 - Azotobacter chroococcum 2 L ha-1; T5 - A. chroococcum 3 L ha-1; T6 - A. chroococcum 4 L ha-1; T7 - P. polymyxa + A. chroococcum 2 L ha-1; T8 - P. polymyxa + A. chroococcum 3 L ha-1; T9 - P. polymyxa + A. chroococcum 4 L ha-1 y T10 - Control (without application). The variables evaluated were: plant height, stem diameter and insertion of the cob. The results showed that at 55 days after sowing (DDS) of the crop, good growth was obtained in the corn plants with a height of 182.01 cm and stem diameter of 20.14 mm with the application of the T9 - P. polymyxa + A. chroococcum. In addition, the insertion of the cob was also at 120 cm in height, for this same treatment. [ABSTRACT FROM AUTHOR]

This article, titled "Editorial: The impact of the space environment on microbial growth and behavior," discusses the role of microorganisms in adapting to and surviving in harsh environments, including space. The article highlights the unique stressors that microbes face in space, such as microgravity and radiation, and explores how they adapt and respond to these conditions. The research presented in this article includes studies on the survival and behavior of microorganisms in simulated space conditions, as well as the implications for space exploration and astrobiology missions. The article emphasizes the importance of understanding microbial behavior in extraterrestrial settings and the need for careful consideration of planetary protection. [Extracted from the article]

Introduction: There is a lack of international consensus as to whether high‐ or low‐level disinfection (HLD or LLD) is required for ultrasound (US) transducers used during percutaneous procedures. This study compared the effectiveness of LLD to HLD on US transducers contaminated with microorganisms from skin. Methods: Two identical linear US transducers repeatedly underwent either LLD or HLD during the study. Randomization determined which of these transducers was applied to left and right forearms of each participant. Swabs taken from transducers before and after reprocessing were plated then incubated for 4–5 days, after which colony forming units (CFU) were counted and identified. The primary hypothesis was the difference in the proportion of US transducers having no CFUs remaining after LLD and HLD would be less than or equal to the noninferiority margin of −5%. Results: Of the 654 recruited participants 73% (n = 478) had microbial growth from both transducers applied to their left and right forearms before reprocessing. These were included in the paired noninferiority statistical analysis where, after disinfection, all CFUs were eliminated in 100% (95% CI: 99.4–100.0%) of HLD transducer samples (n = 478) and 99.0% (95% CI: 97.6–99.7%) of LLD transducer samples (n = 473). The paired difference in the proportion of transducers having all CFUs eliminated between LLD and HLD was −1.0% (95% CI: −2.4 to −0.2%, P‐value <.001). Conclusions: Disinfection with LLD is noninferior to HLD when microorganisms from skin have contaminated the transducer. Therefore, using LLD for US transducers involved in percutaneous procedures would present no higher infection risk compared with HLD. [ABSTRACT FROM AUTHOR]

This investigation seeks to determine the antibiotic-producing potential of bacteria in inhibiting the growth of other organisms like Staphylococcus aureus and Escherichia coli. The bacterial isolates were identified using standard cultural, morphological, and biochemical characterization. These were further screened for their antibiotic-producing potential using the Mueller Hinton agar (MHA) media. The identified bacterial isolates had a mean viable count ranging between 1.38×106/1,380,000 cfu/ml and 1.52×106/1,520,000 cfu/ml. Micrococcus roseus, Brevibacterium species, Bacillus subtilis, Bacillus anthracis, and Bacillus cereus were the predominant bacterial isolates. Nonetheless, the antibiotic test revealed that Bacillus subtilis and Bacillus anthracis showed antimicrobial activity against S. aureus, whereas Bacillus anthracis, Bacillus cereus, and Bacillus subtilis showed zones of inhibition against E. coli. This study shows that Bacillus species have the potential to produce antibiotics and can be used to control microbial growth in the future. [ABSTRACT FROM AUTHOR]

Humans are exposed to diverse communities of microbes every day. With more time spent indoors by humans, investigations into the communities of microbes inhabiting occupied spaces have become important to deduce the impacts of these microbes on human health and building health. Studies so far have given considerable insight into the communities of the indoor microbiota humans interact with, but mainly focus on sampling surfaces or indoor dust from filters. Beneath the surfaces though, building envelopes have the potential to contain environments that would support the growth of microbial communities. But due to design choices and distance from ground moisture, for example, the temperature and humidity across a building will vary and cause environmental gradients. These microenvironments could then influence the composition of the microbial communities within the walls. Here we present a case study designed to quantify any patterns in the compositions of fungal and bacterial communities existing in a building envelope and determine some of the key variables, such as cardinal direction, distance from floor or distance from wall joinings, that may influence any microbial community composition variation. By drilling small holes across walls of a house, we extracted microbes onto air filters and conducted amplicon sequencing. We found sampling height (distance from the floor) and cardinal direction the wall was facing caused differences in the diversity of the microbial communities, showing that patterns in the microbial composition will be dependent on sampling location within the building. By sampling beneath the surfaces, our approach provides a more complete picture of the microbial condition of a building environment, with the significant variation in community composition demonstrating a potential sampling bias if multiple sampling locations across a building are not considered. By identifying features of the built environment that promote/retard microbial growth, improvements to building designs can be made to achieve overall healthier occupied spaces. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Enteral nutritional supplements are used in many medical facilities and home care, but require appropriate management because they are nutrient-rich products. Recently, infection control methods for Ready To Hang (RTH) preparations, which are widely used and are expected to reduce the risk of infection, have not been established in Japan and are dependent on caregivers. Therefore, we evaluated the difference in the growth of microorganisms depending on the type of enteral nutrients following contamination with microorganisms. Methods: Nine types of enteral nutrition were used. Escherichia coli (E. coli) W3110, Serratia marcescens (S. marcescens) NBRC3046, and Candida albicans (C. albicans) IFM61197 were used as test bacteria. The bacterial solution was added to the enteral nutritional supplement, adjusted, and the number of bacteria was measured at 0, 4, 8, and 24 h after the addition of the bacterial solution at 25 °C and in the dark. Results: E. coli and S. marcescens grew in RACOL®-NF SemiSolid for Enteral Use, Hine® Jerry AQUA, and Mermed Plus® over a 24-h period; however, a decrease was observed for other enteral nutrition products. In contrast, C. albicans grew in all enteral nutrition products. Conclusion: Because the viscosity and calorie content vary among enteral nutrition preparations in which growth was observed, we found that pH had the greatest effect on the differences in bacterial growth. Nonetheless, C. albicans growth occurred in all nine types of enteral nutrients, indicating that unlike bacteria, its growth was independent of pH. If semi-solid enteral nutrients are contaminated with microorganisms for any reason, microorganisms will grow, so appropriate infection control is necessary to prevent infection. [ABSTRACT FROM AUTHOR]

A seven-week study was conducted to determine the effects of the replacement of maize with TRM treated with effective microorganisms on the growth performance of broiler chickens (cobb-500). In a completely randomized design, 2*3 factorial, the first factor corresponded to the EM (with and without), and the second factor corresponded to the taro levels (0%, 30%, and 45%), 216 unsexed, day-old broiler chickens were used for the study divided into 6 treatments and 3 replicates. Each treatment contained (T1) 0% TRM without EM (negative control); (T2) 30% TRM without EM; (T3) 45% TRM without EM; (T4) 0% TRM with-EM (positive control); (T5) 30% TRM with-EM; (T6) 45% TRM with-EM of the total diets. There were (p <.001) interaction effects (TRM level*EM) on DM intake, BWG (p <.001), and FCR (p <.05), during the starter, finisher, and overall periods. A higher improvement (p <.001) on DM intake and BWG was observed from broiler fed T6. In addition, T6 had comparable (p <.05) with the T4 group broilers. There were significant (p <.05) reductions in antinutritional factors concentrations in EM-fermented taro root than that unfermented one. Therefore, it had seen that the replacement of maize at 45% TRM with-EM in diets improved the growth performance of broiler chicken. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chapingo Serie Horticultura is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Efforts to isolate uncultured microorganisms over the last century and a half, as well as the advanced 'omics' technologies developed over the last three decades, have greatly increased the knowledge and resources of microbiology. However, many cellular functions such as growth remain unknown in most of the microbial diversity identified through genomic sequences from environmental samples, as evidenced by the increasingly precise observations of the phenomenon known as the 'great plate count anomaly'. Faced with the many microbial cells recalcitrant to cultivation present in environmental samples, Epstein proposed the 'scout' model, characterised by a dominance of dormant cells whose awakening would be strictly stochastic. Unfortunately, this hypothesis leaves few exploitable possibilities for microbial cultivation. This review proposes that many microorganisms follow the 'comfort timing' strategy, characterised by an exit from dormancy responding to a set of environmental conditions close to optimal for growth. This 'comfort timing' strategy offers the possibility of designing culture processes that could isolate a larger proportion of uncultured microorganisms. Two methods are briefly proposed in this article. In addition, the advantages of dormancy, of the 'scout' model and of the 'comfort timing' strategy for survival under difficult conditions, but also for colonisation of environments, are discussed. [ABSTRACT FROM AUTHOR]

Background: Smartphone use has increased exponentially, having formed an integral part of the COVID-19 pandemic era, especially in the academic arena. It has been established that fomites can harbour potentially pathogenic microorganisms, which pose health risks to humans, particularly to the immunocompromised. The purpose of this study was to determine which microorganisms were harboured on the surfaces of smartphones, document the device sanitisation and hand hygiene habits of students within a university cohort, and determine associations of these habits with microorganism colonisation on smartphones. Methodology: This study prospectively sampled 168 randomly selected students from different departments at the Durban University of Technology (DUT). After informed consent, a swab sample from each participant's smartphone was collected and transported to the microbiology laboratory for culture following standard microbiological guidelines. Participants were also asked about device sanitisation and their awareness of smartphones harbouring microorganisms. IBM Statistical Package for Social Sciences (SPSS) Statistics V.27 was used for data analysis with the use of descriptive statistics, Pearson chi-square and Pearson's correlation tests. Results: From the 168 participants, microorganisms were detected in 113 (67.3%) samples, from which 20 different microorganisms were isolated. The majority of microorganisms (n = 17; 73.7%) were opportunistic pathogens. Out of the 168 questionnaire responses, only 36 (21.4%) study participants sanitised their smartphones despite 97 (57.7%) stating that they were aware of smartphones harbouring microorganisms. Conclusion: This study reports a high prevalence of microorganisms harboured on smartphones. The isolation of opportunistic pathogens, as well as the low frequency of smartphone sanitisation, raises a need for awareness of the contamination of smartphones and the potential risk of infection. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the application of microorganisms with native strains on the growth of Morus alba Linn under semi-controlled conditions. Materials and Methods: The work was carried out at the Mountain Development Center, El Salvador municipality, Guantánamo province. Stakes of M. alba, 30 cm long with five buds, were used. Fersialytic soil and organic matter (sheep manure) were used as substrate in a 3:1 ratio. Four concentrations of the microorganism with native strains were applied: 5, 10, 15 and 20 mL/L, which constituted the treatments. A control was used, with water only. A complete randomized experimental design was applied, with 20 plants per treatment. Measurements were branch number, root number, leaf number, branch length, stem diameter and root length. The data were processed from a simple classification analysis of variance. Results: There were no significant differences for the number of branches and number of leaves. Regarding the number of roots, the best treatment was T2, which differed significantly from the others. Treatments T2 and T3 tended to have the highest numerical values. As for branch length and root length, there were significant differences among treatments. No differences were found in stem diameter. The highest numerical values in all indicators were obtained with the application of 5 and 10 mL/L of the bioproduct on M. alba seedlings. Conclusions: With the application of 5 and 10 mL/L of microorganisms with native strains, the performance of branch length, number of roots and root length of M. alba seedlings was favored. [ABSTRACT FROM AUTHOR]

Candida species are considered opportunistic microorganisms present in the normal microbiota of the oral cavity and gastrointestinal and urogenital tracts of human beings. These infections are more common in individuals with compromised immune systems and their frequency has increased over the years. Regarding bioproducts, recent research from natural sources suggest that algae are a promising group in providing new bioactive substances. The objective of this work is to evaluate the antifungal activity and the in vitro modifying potential of the dichloromethane/methanol extract of G. cervicornis against Candida spp. Tests were performed using broth microdilution method to determine the intrinsic activity of the products, and combination therapy with commercial drugs. The intrinsic activity of DMEGC showed fungistatic activity against all Candida species tested at the concentration of 1024 µg/mL. DMEGC at subinhibitory concentrations was able to modify the action of Fluconazole against isolated and standard C. krusei , reducing the amount of drug needed to inhibit the growth of the microorganism by 50% (IC50) by more than 12-fold. The results show that DMEGC can be used to treat C. krusei in combination therapy with commercial antifungals such as Fluconazole. In addition, its fungistatic activity is important to reduce the development of drug resistance. Further studies are needed to verify which compounds isolated from the extract were responsible for its antifungal activity and which mechanisms of action. [ABSTRACT FROM AUTHOR]

The oleaginous yeast Lipomyces starkeyi is expected to be a new lipid source since this microorganism is capable of accumulating more than 85% lipid per dry cell weight. For effective utilization of oleaginous yeast, mutants with improved lipid production compared to the wild-type have been screened by methods such as single-cell sorting and Percoll density gradient centrifugation. Because these methods need to reculture all mutated oleaginous yeasts together in a flask, it is difficult to evaluate the growth of each individual mutant. Thus, screening for the slow-growing mutants with high-throughput has never been performed by conventional methods. In this study, we developed a high-throughput method using gel microdroplets (GMD). With this method, the growth and lipid production of L. starkeyi can be evaluated simultaneously. L. starkeyi grew in GMD and the size of these microcolonies was evaluated by scattered light. Finally, a mutant with a 10-fold delay in growth compared to the wild-type was obtained. Analysis of genetic information in this mutant could reveal valuable information about critical genes involved in the growth of these microorganisms, which could then be utilized further. [Display omitted] • This newly developed GMD method can accurately evaluate the growth of microorganisms. • A mutant that grows significantly slower than the wild-type was obtained. • The screening of about 800,000 GMD was completed in 4 h. • This method could be applied to the screening of slow-growing mutant. [ABSTRACT FROM AUTHOR]

The microorganisms in the water sources are closely related to drip irrigation emitter clogging and clogging substances accumulation. However, few studies quantitatively considered the role of microorganisms in the emitter clogging process, especially in the high-sediment water source. The coupling process and mechanism between solid particles and microorganisms are not clear yet. Based on these, the Yellow River water (CK), general high sediment water (GHS) and artificial simulated Yellow River water (SYR) was applied in an indoor controllable experiment to study the long-term dynamic drip irrigation emitter clogging process, microorganism growth and its secretions as well as clogging substances accumulation. The results showed that the presence of microorganisms could accelerate the clogging process, with smaller discharge ratio variation (Dra) and Christiansen coefficient of uniformity (CU), and higher accumulation of clogging substances. Among them, the Dra and CU of the SYR treatment were the smallest at the end of the experiment (14.7% and 30.5%, respectively) and those of the GHS treatment were the largest (21.2% and 33.9%, respectively). Meanwhile, the total amounts of phospholipid fatty acids (PLFAs), extracellular polymer substances (EPS) and dry weight (DW) in SYR treatment were the highest, which were 110.2%, 23.8% and 16.7% higher than those in GHS treatment, respectively. The clogging parameters and clogging substances accumulated from the CK treatment were in a state of in-betweenness. However, the differences between CK and SYR treatments did not reach a significant level, while they were both significantly different from GHS treatment (p < 0.05). This mainly resulted from the interactions between solid particles and microorganisms in the drip irrigation emitter clogging process. Ignoring the existence of microorganisms may overestimate the Dra and CU by 6.5% and 3.4%, respectively. This offered theoretical references to the application of high-sediment water in the drip irrigation system. [ABSTRACT FROM AUTHOR]

Aims: The effect of Eucalyptus stump substrate decomposition on microbial resource limitation driving factors are unclear. Methods: Eucalyptus stump substrate samples from five decay classes with contrasting qualities were decomposed in Eucalyptus undergrowth soil for three months in a laboratory microcosm experiment. We determined the substrate quality, microbial biomass, microbial community structure, and extracellular enzyme activities for the decay classes of stump substrates. Results: The stump carbon:nitrogen (C:N), carbon:phosphorus (C:P), and nitrogen:phosphorus (N:P) ratios and dissolved organic carbon:total dissolved nitrogen (DOC:TDN), dissolved organic carbon:available phosphorus (DOC:AP), and total dissolved nitrogen:available phosphorus (TDN:AP) ratios increased and then decreased as the decay class increased, whereas the C:N and C:P imbalances between the microorganisms inhabiting stumps and their resources increased. The activities of N- and P-acquiring enzymes improved as the decay class increased, and such changes improved the microbial N and P limitation of stumps and reduced the microbial C use efficiency. In advanced decay classes, the microbial community structure shifted toward a higher ratio of fungi to bacteria and a lower ratio of gram-positive bacteria to gram-negative bacteria. Redundancy analysis showed that P, DOC, and DOC:AP were all closely related to the enzyme activities, whereas P and N were the critical factors alter microbial composition community. In addition, ecoenzymatic stoichiometry and the C:N:P imbalance played key roles on regulating microbial C use efficiency. Conclusions: The decomposition of Eucalyptus stump substrates modified microbial communities and enzymatic stoichiometry, leading to microbial growth from P limitation to N limitation. [ABSTRACT FROM AUTHOR]

This study compared the minimal inhibition concentrations (MICs) and their effects on the growth kinetics of seven different types of zinc (Zn) compounds and Na2EDTA in the case of three typical commensal beneficial microorganisms (Bacillus subtilis, Lactococcus lactis, and Saccharomyces cerevisiae). The seven Zn compounds included ZnSO4, four Zn–amino acid chelates, and two Zn–EDTA complexes. Both MICs and growth kinetic parameters indicated that different microorganisms show different sensitivities; for example, B. subtilis, L. lactis, and S. cerevisiae were most sensitive to ZnSO4, Na2EDTA, and Zn(NH3)2(Gly)2, respectively. Both ZnEDTA and Zn(NH3)2(Lys)2 improved the growth rate of all beneficial commensal intestinal microorganisms at low concentrations (5–10 mg/L) and showed low toxicity towards all tested strains. At higher concentrations (100–500 mg/L), all compounds decreased the growth rate and increased the lag phase. In conclusion, both growth kinetic parameters and MICs tested effectively measured the inhibitory effects of the test materials; however, growth kinetics provides a more detailed picture of the concentration-dependent effects and those on the mechanisms of microbial growth inhibition. [ABSTRACT FROM AUTHOR]

The main microbial contaminants of rooms in which laboratory rodents are housed are bacteria and fungi. Restriction of microbial growth to below threshold levels requires the application of various sophisticated antimicrobial techniques that must be effective and safe for the animals. Some of the most commonly used techniques, including chemical disinfection, ventilation, filtration, sterilization and radiation, are not always sufficiently effective. The aim of the current study was to evaluate the efficacy of a modern technique (i.e. radiant catalytic ionization (RCI)) on the microbiological status of an animal care facility, and the health of the mice housed therein. The experiment, conducted over seven days, compared an experimental room with an RCI system permanently turned on with a negative control room. At the completion of the experiment, the number of bacteria in the RCI room air and on its walls was lower than that in the control room (p < 0.01 in both cases). Values of the basic prooxidative parameter, thiobarbituric acid reactive substances concentration, in tissues of mice from the RCI room were within allowed boundaries. Hence, application of an RCI system proved to be an ideal technique to ensure high hygienic standards in animal rooms without any adverse effects on the animals housed therein. [ABSTRACT FROM AUTHOR]

Nitrate/nitrite-dependent anaerobic methane oxidation (n-DAMO) process is a promising wastewater treatment technology, but the slow microbial growth rate greatly hinders its practical application. Although high-level nitrogen removal and excellent biomass accumulation have been achieved in n-DAMO granule process, the formation mechanism of n-DAMO granules remains unresolved. To elucidate the role of functional microbes in granulation, this study attempted to cultivate granules dominated by n-DAMO microorganisms and granules coupling n-DAMO with anaerobic ammonium oxidation (Anammox). After long-term operation, dense granules were developed in the two systems where both n-DAMO archaea and n-DAMO bacteria were enriched, whereas granulation did not occur in the other system dominated by n-DAMO bacteria. Extracellular polymeric substances (EPS) measurement indicated the critical role of EPS production in the granulation of n-DAMO process. Metagenomic and metatranscriptomic analyses revealed that n-DAMO archaea and Anammox bacteria were active in EPS biosynthesis, while n-DAMO bacteria were inactive. Consequently, more EPS were produced in the systems containing n-DAMO archaea and Anammox bacteria, leading to the successful development of n-DAMO granules. Furthermore, EPS biosynthesis in n-DAMO systems is potentially regulated by acyl-homoserine lactones and c-di-GMP. These findings not only provide new insights into the mechanism of granule formation in n-DAMO systems, but also hint at potential strategies for management of the granule-based n-DAMO process. • Dense granules were developed in the systems containing n-DAMO archaea. • Granulation was not observed in the system without n-DAMO archaea. • EPS production may be a determining factor of the formation of n-DAMO granules. • n-DAMO archaea and Anammox bacteria were active in EPS biosynthesis. • EPS production in n-DAMO granules is potentially regulated by AHLs and c-di-GMP. [ABSTRACT FROM AUTHOR]

Introduction: The growing Earth population requires the aquaculture production expansion and intensification. Interest in biofloc-based systems has increased because they can provide biosecurity, are financially sustainable, and can be applied in a variety of systems. Objective: To carry out a scientific literature review about the importance of biofloc in aquaculture. Materials and Methods: An information search was carried out in specialized scientific literature; synthesizing the most important, for which it was possible to define the concept of Biofloc, its most relevant characteristics, development conditions, as well as other aspects of vital importance for this technology understanding and application. Results and Discussion: Bioflocs are a community formed by microorganisms associated with each other in a suspended substrate that responds to trophic mesh dynamics. Biofloc development is affected by many factors and its nutritional quality is similar than the food obtained by species grown in their natural habitat. The most used carbon sources in biofloc systems are: sugar, molasses and starch; however, agro-industrial waste is rich in bioactive compounds, so it can be used as raw material for microbial growth. Conclusions: Although much remains to be known, the fact that biofloc technology conceptually declared the wastes as an opportunity for on-site production makes it a possible and eco-friendly alternative. [ABSTRACT FROM AUTHOR]

Different cutting types not only affect the quality and bioactive substances of broccoli but may produce wounding stress that influences the quantity and diversity of microorganisms and finally leads to safety concerns. In this study, three different fresh-cutting types (floret (F), quarterly cut floret (QF) and shredded floret (FS)) and four storage stages (0, 1, 2 and 3 day(s)) were designed to detect the bacterial diversity in broccoli. Results showed that the quantity and growth of microorganisms in fresh-cut broccoli were positively correlated with the intensity of fresh-cut damage, and the 97 strains isolated using 16S rRNA gene sequences were mainly classified into four phyla: Proteobacteria, Actinobacteria, Bacteroidetes and Firmicutes. The predominant phylum was Proteobacteria, dominated by Pseudomonas spp. and Acinetobacter spp. Four representative strains of different species were selected to analyze their spoilage potential on fresh-cut broccoli. Pseudomonas spp. had great impacts on the corruption of broccoli, which affected fresh-cut broccoli by metabolizing to produce nitrite and consuming nutrition. Moreover, Comamonas spp. and Acinetobacter spp. also affected the quality of broccoli, but received little attention previously. This study provides a reference for precise bacteriostasis and preservation of fresh-cut vegetables such as broccoli. [ABSTRACT FROM AUTHOR]

The prevalence of multidrug-resistant microorganisms results in an urgent need for the development of new antimicrobial agents or new treatment strategies. In this sense, plants serve different alternatives. Berberine, a plantderived compound, is one of the alkaloids known to display antimicrobial activity against several types of microorganisms, while its being a substrate of various efflux pumps causes a decrease in its efficacy. Biotransformation makes it possible to obtain novel or more effective compounds with only minor structural modifications using enzyme systems. In this study, biotransformation of berberine by Curvularia lunata was examined. The working concentration of berberine was determined by observing the microbial growth on agar plates. The concentration of residual berberine in the media was analyzed by HPLC. In addition, laccase and beta-glucosidase enzyme activities were followed for their possible roles during the biotransformation of berberine. The results show that at the end of 14 days, C. lunata consumed 99% and 87% of berberine with the initial concentrations of 0.35 mg/mL and 0.5 mg/mL, respectively. Enzyme activities were not affected significantly. Since the concentration of berberine decreased, the biotransformation of berberine by C. lunata could be mentioned. Monitoring of biotransformation products plays a crucial role in discovering novel antimicrobial compounds and new valuable molecules. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Moss-dominated biocrusts (moss crusts) are a feasible approach for the ecological restoration of drylands, but difficulty obtaining inoculum severely limits the progress of large-scale field applications. Exogenous microorganisms could improve moss growth and be conducive to moss inoculum propagation. In this study, we investigated the growth-promoting effects and potential mechanisms of exogenous microorganism additives on moss crusts. We used an incubator study to examine the effects of inoculation by heterotrophic microorganisms (Streptomyces pactum , Bacillus megaterium) and autotrophic microorganisms (Chlorella vulgaris , Microcoleus vaginatus) combined with Artemisia sphaerocephala gum on the growth of Bryum argenteum , the dominant moss crusts species in sandy deserts. Amplicon sequencing (16S and 18S rRNA) and PICRUSt2 were used to illustrate the microbial community structure and potential function in the optimal treatment at different developmental stages. Our results showed that exogenous microorganisms significantly promoted moss growth and increased aboveground biomass. After 30 days of cultivation, the Streptomyces pactum (1 g kg–1 substrate) + Chlorella vulgaris (3.33 L m–2) treatment presented optimal moss coverage, height, and density of 97.14%, 28.31 mm, and 2.28 g cm–2, respectively. The best-performing treatment had a higher relative abundance of Streptophyta—involved in moss growth—than the control. The control had significantly higher soil organic carbon than the best-performing treatment on day 30. Exogenous microorganisms improved eukaryotic community diversity and richness and may enhance soil microbial functional and metabolic diversity, such as growth and reproduction, carbon fixation, and cellulose and lignin decomposition, based on functional predictions. In summary, we identified the growth-promoting mechanisms of exogenous additives, providing a valuable reference for optimizing propagation technology for moss inoculum. [ABSTRACT FROM AUTHOR]

The present work investigated the ability of antagonistic microorganisms to inhibit the growth of pathogenic strains responsible for the vascular fusarium wilt of date palm or Bayoud's disease. The objective was to evaluate the antagonistic effect of native strains of Trichoderma longibarchiatum, Penicillium sp., Fusarium sp. and one isolate of Bacillus sp. against four isolates of Fusarium oxysporum f.sp. albedinis (Foa) under in vitro conditions. The isolates Bacillus sp. and Fusarium sp. were isolated from soil samples of the rhizosphere of date palm of Tamanrasset region in Algeria, these strains were morphologically identified, and a dual culture confrontation was carried out, placing the Foa in the center of the Petri dish and Bacillus sp. in the two cardinal points. For T. longibarchiatum, Penicillium sp. and Fusarium sp. they were confronted against Foa with a dual confrontation, the inhibition rates were determined, and a percentage of inhibition obtained varied from 64.29 to 65.75%; 57.14 to 64.29% and 36.36 to 52.05% for T. longibarchiatum, Penicillium sp and Fusarium sp. respectively. While Bacillus sp. exhibits the lowest percentage of inhibition in this study, and they were less than 16.67%. Comparison of mean value for each pair between T. longibrachiatum, Penicillium sp., Fusarium sp. on one hand and Bacillus sp. on the other hand concluded that there is a highly significant difference between these three fungal isolates and Bacillus sp. concerning inhibition rates with P-value (P <0.0001). Contrary, no significant difference was observed between T. longibrachiatum and Penicillium sp. with P = 0.1895 and the two antagonists show the same letter A in the letter connection ratio, which means no difference in the level of inhibition. [ABSTRACT FROM AUTHOR]

Coalbedmethane (CBM) is a significant unconventional natural gas source on earth and has been extracted commercially. Numerous environmental questions flank the commercial CBM expansion. This study examined to explore microbial population in produced water of CBM growth in Jharkhand, India. Additionally, the current study focused on understanding the water as an indigenous microbial habitat on biological facts and nutrient accessibility and utilization of produced water and microbes therein. The results suggest the existence of numerous microbial communities (bacteria, archaea, actinomycetes, and fungi) in water, which may add from coal deposit. The isolate was related to Methanobacterium sp., a methanogenic archaebacteria. The study proposed that laboratory-based supplements enhance native microbial growth. Ni, Zn, Cu, Mn, B, Fe, and Se are detected in produced water, and the overall data suggest that nutrients in water may encourage native microbial growth. Therefore, the described work expands our understanding on microbial life in deep-underground in context to geomicrobiology of that region. Furthermore, it offers insight into the utilization of produced water and the abundance of indigenous microbial assemblage may aid in the biotransformation of organic material. Future research is needed to examine the diversity of microbes in water and to identify cost-effective alternatives to chemically defined medium. [ABSTRACT FROM AUTHOR]

The potential of tragacanth (TG) coating incorporated with Persian lime peel extract (PLPE) for reducing 50% of sodium metabisulfite (SMS) in shrimp was investigated. Four groups of shrimps immersed in water (Control), 1.25% SMS solution (SMS), TG with 1% PLPE, and 0.625% SMS (TSL1%), and TG containing 2% PLPE and 0.625% SMS (TSL2%) and analyzed for different quality characteristics over 10 days at 4°C. The TSL extended the microbial shelf life of shrimp by about 6 and 2 days, respectively, compared with the control and SMS groups. It also resulted in lower volatile base nitrogen, trimethylamine, and lipid peroxidation compared with the control and SMS (p <.05). The TG+PLPE+SMS also improved the sensory attributes and reduced the color changes and melanosis of shrimp more than the SMS. Therefore, using a combination of TG and PLPE can prolong the shelf life and reduce the sulfite residue in shrimp during cold storage. Novelty impact statement: In this study, we have investigated the ability of substitution 50% of SMS by TG coating incorporated with PLPE in the shelf life extension of shrimp during refrigeration. The incorporation of PLPE and a half dose of SMS in TG coating increased the shelf life of shrimp, as shown by: (1) the retardation of the microbial growth for about 6 days; (2) reduction of the TVBN, TMA‐N, and TBA production for about 90, 75, and 50%, respectively; and (3) retardation of melanosis and sensory changes. TG coating incorporated with PLPE and a half dose of SMS may serve as an active coating for shrimp preservation. [ABSTRACT FROM AUTHOR]

The application of thermodynamics to microbial growth has a long tradition that originated in the middle of the 20th century. This approach reflects the view that self-replication is a thermodynamic process that is not fundamentally different from mechanical thermodynamics. The key distinction is that a free energy gradient is not converted into mechanical (or any other form of) energy but rather into new biomass. As such, microbes can be viewed as energy converters that convert a part of the energy contained in environmental nutrients into chemical energy that drives self-replication. Before the advent of high-throughput sequencing technologies, only the most central metabolic pathways were known. However, precise measurement techniques allowed for the quantification of exchanged extracellular nutrients and heat of growing microbes with their environment. These data, together with the absence of knowledge of metabolic details, drove the development of so-called black-box models, which only consider the observable interactions of a cell with its environment and neglect all details of how exactly inputs are converted into outputs. Now, genome sequencing and genome-scale metabolic models (GEMs) provide us with unprecedented detail about metabolic processes inside the cell. However, mostly due to computational complexity issues, the derived modelling approaches make surprisingly little use of thermodynamic concepts. Here, we review classical black-box models and modern approaches that integrate thermodynamics into GEMs. We also illustrate how the description of microbial growth as an energy converter can help to understand and quantify the trade-off between microbial growth rate and yield. [ABSTRACT FROM AUTHOR]

Plants are surrounded by a vast diversity of microorganisms. Limiting pathogenic microorganisms is crucial for plant survival. On the other hand, the interaction of plants with beneficial microorganisms promotes their growth or allows them to overcome nutrient deficiencies. Balancing the number and nature of these interactions is crucial for plant growth and development, and thus, for crop productivity in agriculture. Plants use sophisticated mechanisms to recognize pathogenic and beneficial microorganisms and genetic programs related to immunity or symbiosis. Although most research has focused on characterizing changes in the transcriptome during plant-microbe interactions, the application of techniques such as Translating Ribosome Affinity Purification (TRAP) and Ribosome profiling allowed examining the dynamic association of RNAs to the translational machinery, highlighting the importance of the translational level of control of gene expression in both pathogenic and beneficial interactions. These studies revealed that the transcriptional and the translational responses are not always correlated, and that translational control operates at cell-specific level. In addition, translational control is governed by ciselements present in the 50mRNA leader of regulated mRNAs, e.g. upstream open reading frames (uORFs) and sequence-specific motifs. In this review, we summarize and discuss the recent advances made in the field of translational control during pathogenic and beneficial plant-microbe interactions. [ABSTRACT FROM AUTHOR]

Copyright of Universitas Scientiarum is the property of Pontificia Universidad Javeriana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background. Despite endoscope reprocessing, residual droplets remain in gastrointestinal endoscope working channels. Inadequate drying of gastrointestinal endoscope working channels may promote microbial reproduction and biofilm formation, increasing the risk of infection in patients. This review was designed to provide the current status of gastrointestinal endoscope drying, emphasize the importance of gastrointestinal endoscope drying, and evaluate the effectiveness of different drying methods of gastrointestinal endoscope in reducing residual droplets and microbial growth risk. Methods. A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting checklist. The PubMed, Web of Science, Medline, EMBASE, EBSCO, CNKI, CQVIP, and Wanfang Data databases were searched from 2010 to 2020 to identify eligible articles focused on methods of gastrointestinal endoscope drying and the status of endoscope drying. The following key points were analyzed: type of intervention, amount of residual droplets, major microbial types, and effectiveness of biofilm intervention. JBI quality assessment tool was used to determine bias risk for inclusion in the article. Results. This review included twelve articles. Two of the articles reported lack of drying of gastrointestinal endoscopes while the other ten reported residual droplets, microbial growth, and biofilm formation after different methods of drying. Four articles reported 0 to 4.55 residual droplets; four articles reported that the main microbial types were cocci and bacilli, most commonly Staphylococcus, Escherichia coli, Bacillus maltophilia, and Pseudomonas aeruginosa; and two reported that drying could effectively reduce biofilm regeneration. The type of intervention is as follows: automatic endoscopy reprocessor (AER), manual compressed air drying, and the Dri-Scope Aid for automatic drying and drying cabinet. Conclusions. While endoscope reprocessing may not always be effective, an automatic endoscope reprocessor plus the Dri-Scope Aid with automatic drying over 10 min or storage in a drying cabinet for 72 h may be preferred. [ABSTRACT FROM AUTHOR]

In tropical forest ecosystems leaf litter from a large variety of species enters the decomposer system, however, the impact of leaf litter diversity on the abundance and activity of soil organisms during decomposition is little known. We investigated the effect of leaf litter diversity and identity on microbial functions and the abundance of microarthropods in Ecuadorian tropical montane rainforests. We used litterbags filled with leaves of six native tree species (Cecropia andina, Dictyocaryum lamarckianum, Myrcia pubescens, Cavendishia zamorensis, Graffenrieda emarginata, and Clusia spp.) and incubated monocultures and all possible two‐ and four‐species combinations in the field for 6 and 12 months. Mass loss, microbial biomass, basal respiration, metabolic quotient, and the slope of microbial growth after glucose addition, as well as the abundance of microarthropods (Acari and Collembola), were measured at both sampling dates. Leaf litter diversity significantly increased mass loss after 6 months of exposure, but reduced microbial biomass after 12 months of exposure. Leaf litter species identity significantly changed both microbial activity and microarthropod abundance with species of high quality (low C‐to‐N ratio), such as C. andina, improving resource quality as indicated by lower metabolic quotient and higher abundance of microarthropods. Nonetheless, species of low quality, such as Clusia spp., also increased the abundance of Oribatida suggesting that leaf litter chemical composition alone is insufficient to explain variation in the abundances of soil microarthropods. Overall, the results provide evidence that decomposition and microbial biomass in litter respond to leaf litter diversity as well as litter identity (chemical and physical characteristics), while microarthropods respond only to litter identity but not litter diversity. [ABSTRACT FROM AUTHOR]

Phosphate solubilizing microorganisms were isolated in vitro experiment, and wheat crop were planted in pots for 5 month and treated with rock phosphate, manure and with combination treatments of rock phosphate, manure, and phosphate solubilizing microorganisms to compare with control treatment. The result shows that the solubilizing index ranged between 1.4 to 1.6 for isolated microorganisms, the decrease in soil pH which have enormous influence in phosphate solubility were significantly influenced by the addition of phosphate solubilizing microorganisms and manure is 6.5 pH comparing with 8 pH for control. Soil soluble and extractable phosphorous also increased by combination of phosphate solubilizing microorganisms and manure recording 0.46±0.03 ppm and 10.7±1.01 ppm respectively comparing to 0.39±0.01 ppm and 0.75±0.11ppm for control after one month of experiment, and this significance continued to 3 and 5 month after planting followed by the combination treatment of rock phosphate and phosphate solubilizing microorganisms. Total phosphorous in both wheat shoot and root after 5 month of planting were increased significantly by the addition of phosphate solubilizing microorganisms and manure to record 0.792±0.11% in shoot and 0.66±0.13% in roots and more than other treatments, however the translocation of phosphorous is harder than nitrogen from roots to shoots. The addition of phosphate solubilizing microorganisms enhanced the growth ratio of wheat up to 96±5 comparing to 40±3 for control. [ABSTRACT FROM AUTHOR]

The article focuses on a study proposing a microbial consortium approach to more efficiently break down plastic waste by combining strains of bacteria, addressing challenges faced by single strains in handling mixed substrates; researchers engineered bacteria strains to specialize in assimilating specific plastic components, demonstrating improved efficiency in the degradation process compared to individual strains.

Clinical trials and animal studies on the gut microbiota are often limited by the difficult access to the gut, restricted possibility of in vivo monitoring, and ethical issues. An easily accessible and monitorable in vitro model of the gut microbiota represents a valid tool for a wider comprehension of the mechanisms by which microbes interact with the host and with each other. Herein, we present a novel and reliable system for culturing the human gut microbiota in vitro. An electrospun gelatin structure was biofabricated as scaffold for microbial growth. The efficiency of this structure in supporting microbial proliferation and biofilm formation was initially assessed for five microbes commonly inhabiting the human gut. The human fecal microbiota was then cultured on the scaffolds and microbial biofilms monitored by confocal laser and scanning electron microscopy and quantified over time. Metagenomic analyses and Real-Time qPCRs were performed to evaluate the stability of the cultured microbiota in terms of qualitative and quantitative composition. Our results reveal the three-dimensionality of the scaffold-adhered microbial consortia that maintain the bacterial biodiversity and richness found in the original sample. These findings demonstrate the validity of the developed electrospun gelatin-based system for in vitro culturing the human gut microbiota. [ABSTRACT FROM AUTHOR]

Copyright of News of Kazakhstan Science / Novosti nauki Kazahstana is the property of NCSTE (JSC National Center for State Scientific and Technical Evaluations) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, Reactive Black 5 bioremoval by Penicillium citrinum was investigated. Common agricultural by-products of the food industry, such as apple and carrot pomaces were used as carbon sources. Carrot and apple pomace were pretreated hydrothermally, and the effects of some critical parameters such as pH, initial biomass and dye loadings on Reactive Black 5 bioremoval were investigated. P. citrinum removed 80.87% of the dye in the presence of 16% carrot pomace, pH 5 and 225.9 mg/L initial dye loading, respectively. The maximum specific dye uptake rate was found as 52.92 mg/g under the same conditions. Moreover, notably bioremoval was observed even in high Reactive Black 5 concentrations such as 758.2 mg/L. The results showed that P. citrinum is a suitable microorganism for dye removal, and carrot and apple pomaces can be evaluated for microbial growth as a cheap carbon sources. [ABSTRACT FROM AUTHOR]

Quartz crystal microbalance (QCM) sensors are becoming a good alternative to analytical methods for the measurement of bacterial growth in liquid media culture. For this purpose, two essential resonance parameters allow the monitoring of biofilm formation: the series resonance frequency shift and the change of the resistance at this frequency. Nevertheless, several problems arise in determining these parameters, as their relative variation is very small. This means that an accurate procedure must be implemented for the measurement of the QCM resonance parameters, including the automatic calibration of the frequency response effects of the measurement circuits and the automatic compensation of the static electrical capacitance of the QCM. In this article, a novel multichannel system for on-line monitoring of biofilm formation based on QCM sensors is proposed. QCM resonance parameters are determined from the electrical impedance analysis by means of an auto-balanced impedance bridge. This configuration has allowed the implementation of an affordable multichannel measurement instrument. Obtained results, based on binary mixtures of water–glycerol measurements and real microorganism experiments, are in good agreement with the theoretical behavior. These results show the great potential of this instrument to be used for monitoring microbial growth and biofilm formation. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Feilaifeng is listed as a cultural heritage site because of its abundant Buddhist statues possibly dating back to the Five Dynasties period (907 AD–960 AD). However, microorganism growth on the surface of stone results in esthetic and structural damage. Biocide treatment is commonly used to eradicate the microorganisms, and we assessed the effectiveness of four chemicals (benzalkonium chloride, octhilinone, tebuconazole, and thiabendazole) and two commercial biocides (ACTICIDE® 50 X (A) and AW-600) in inhibiting microbial colonization. The minimal inhibitory concentrations of various biocides were determined, and their efficacies were compared using the inhibition zone method. The most effective biocides were applied in situ to Feilaifeng Limestone, and the overall effects were monitored by photographic recordings and microbial cultures for a month. The factors affecting the efficacy of each biocide, such as thermal stability and loss-resistance, were also evaluated. The biocides varied markedly in their ability to inhibit the proliferation of different microorganisms. The three species of fungi tested herein demonstrated the highest susceptibility to octhilinone, but benzalkonium chloride showed the best antibacterial activity to the bacteria, Pseudomonas sp. Based on the results of in vitro assays, octhilinone, as well as its respective commercial product AW-600, were the best biocides for treating microorganisms, and 0.5% was the optimal concentration. Although the biocides on disc papers could be easily diluted by water, they were resistant to degradation by high temperatures. These findings suggest that frequent rainfall might have been the reason for the recolonization of microorganisms in a short time after octhilinone and AW-600 treatment in situ. Our results provide new insights on how to protect Feilaifeng Limestone, which is prone to damage caused by various microorganisms. [ABSTRACT FROM AUTHOR]

Summary: Stone surfaces are extreme environments that support microbial life. This microbial growth occurs despite unfavourable conditions associated with stone including limited sources of nutrients and water, high pH and exposure to extreme variations in temperature, humidity and irradiation. These stone‐dwelling microbes are often resistant to extreme environments including exposure to desiccation, heavy metals, UV and Gamma irradiation. Here, we report on the effects of climate and stone geochemistry on microbiomes of Roman stone ruins in North Africa. Stone microbiomes were dominated by Actinobacteria, Cyanobacteria and Proteobacteria but were heavily impacted by climate variables that influenced water availability. Stone geochemistry also influenced community diversity, particularly through biologically available P, Mn and Zn. Functions associated with photosynthesis and UV protection were enriched in the metagenomes, indicating the significance of these functions for community survival on stones. Core members of the stone microbial communities were also identified and included Geodermatophilaceae, Rubrobacter, Sphingomonas and others. Our research has helped to expand the understanding of stone microbial community structure and functional capacity within the context of varying climates, geochemical properties and stone conditions. [ABSTRACT FROM AUTHOR]

Tea is susceptible to physicochemical and microbiological influences during storage and marketing, which seriously hinders the development of the tea industry. However, the tea have short shelf life and industry has not been able to completely eliminate the microbiological safety hazards which seriously hinders the development of tea industry. The study aimed to summarize the meaning and content of the primary or secondary models of microbial growth and analyze the influencing factors of tea quality and established the predictive model of tea shelf life from the perspective of microbiology. To better explore the model of tea microbial growth and predict the shelf life of tea, this study laid a preliminary foundation for the development of the quality and safety of tea or improve the health of tea detection for extending the shelf life. [ABSTRACT FROM AUTHOR]