Saliva-derived microcosm biofilms grown on different oral surfaces in vitro

The microbial composition of a specific oral niche could be influenced by initial bacterial adherence, nutrient and physiological property of the local surface. To investigate the influence of nutrient and surface properties on microbial composition, saliva-derived biofilms were grown in agar on three substrata: Reconstructed Human Gingiva (RHG), a hydroxyapatite (HAP) surface, and a titanium (TI) surface. Agar was mixed with either Brain Heart Infusion (BHI) or Thompson (TP) medium. After 1, 3, or 5 days, biofilm viability (by colony forming units) and microbiome profiles (by 16 S rDNA amplicon sequencing) were determined. On RHG, biofilm viability and composition were similar between BHI and TP. However, on the abiotic substrata, biofilm properties greatly depended on the type of medium and substratum. In BHI, the viability of HAP-biofilm first decreased and then increased, whereas that of TI-biofilm decreased in time until a 6-log reduction. In TP, either no or a 2-log reduction in viability was observed for HAP- or TI-biofilms respectively. Furthermore, different bacterial genera (or higher level) were differentially abundant in the biofilms on 3 substrata: Haemophilus and Porphyromonas for RHG; Bacilli for HAP and Prevotella for TI. In conclusion, RHG, the biotic substratum, is able to support a highly viable and diverse microbiome. In contrast, the viability and diversity of the biofilms on the abiotic substrata were influenced by the substrata type, pH of the environment and the richness of the growth media. These results suggest that the host (oral mucosa) plays a vital role in the oral ecology.

Effects of Bacillus subtilis on Production Performance, Bone Physiological Property, and Hematology Indexes in Laying Hens

This study was to investigate the effects of Bacillus subtilis on production performance and bone pathophysiological characteristics of layers. Twenty-four 48-week-old Lohmann Pink-shell laying hens were randomly divided into two groups: a basic diet (control) and the basic diet mixed with Bacillus subtilis (0.5 g/kg) for a 60-day trial. Statistically, independent-sample t-test was used to assess the treatment differences. The results showed that Bacillus subtilis supplementation improved the percent of marketable eggs (p < 0.05) with reduced numbers of broken and soft-shelled eggs but had no effects on egg weight, height of albumen, yolk color, and Haugh unit (p > 0.05). Bacillus subtilis supplement also elevated maximum load (p = 0.06), maximum stress (p = 0.01), stiffness (p < 0.01), and Young’s modulus (p < 0.01) but suppressed maximum strain (p = 0.06) in the femur. In addition, compared with control birds, phosphorous concentration (p < 0.01) was reduced in serum at day 61 but increased in the femur (p < 0.05) in Bacillus subtilis fed birds. Bacillus subtilis fed birds also had lower magnesium concentrations in both femur (p = 0.04) and feces (p = 0.09). Furthermore, Bacillus subtilis increased plasma estrogen concentration (p = 0.01) and femur TNF receptor superfamily member 11b (OPG) expression (p < 0.05) but reduced plasma IL-1 (p < 0.01) and TNF-α (p < 0.01) concentrations. These results indicate that Bacillus subtilis could be used as a health promotor to reduce overproduction-induced inflammation and associated bone damage and to increase marketable egg production. The data provide evidence for developing a management strategy to use Bacillus subtilis as a feed additive to improve marketable egg production and health and welfare status of laying hens.

Epigenomic stability assessment during cryopreservation and physiology among various strains of Chromochloris zofingiensis (Chlorophyceae) and their genetic variability revealed by AFLP and MS-AFLP

Chromochloris zofingiensis (Dönz) Fucíková & L.A.Lewis, due to its production of highly valuable carotenoids such as astaxanthin, is a model organism in biotechnology. Since the recognition of this physiological property, many biotechnological applications have only used a single strain (SAG 211-14 = CCAP 211/14 = UTEX 32 = ATCC 30412) to produce biomass and carotenoids. However, multiple acquisitions of strains putatively belonging to the same species raised the question of the conspecificity of those strains and their properties. In this study, the conspecificity of the available strains, which are deposited axenically in SAG, was tested using SSU and ITS rDNA sequencing and AFLP (EcoRI/PstI) analyses. The comparison of SSU and ITS rDNA sequences as well as the AFLP patterns revealed that the investigated strains formed two very similar groups, (1) SAG 211-14, SAG 4.80, SAG 31.80, and SAG 34.80 and (2) SAG 221-2. All strains belonged to one species, C. zofingiensis, and represented one monophyletic lineage within the so-called DO-group of the Chlorophyceae. The robustness to cryopreservation and the subsequent epigenetic variability was detected using the methylation-sensitive AFLP (EcoRI/MspI and EcoRI/HpaII) among the five Chromochloris strains. All strains showed a high rate of survival (54.4–98.1%) during cryopreservation. The methylation patterns varied between precryo and postcryo in all strains detected among three time points (before, shortly after, and 8 weeks after cryopreservation), showing that the MS-AFLP technique has the potential to detect epigenetic effects occurring in response to cryopreservation and other stresses. Finally, the potential of these five strains for usage in biotechnological applications was proven by growing them in aerated cultures with and without additional carbon dioxide supply. The comparison showed that all strains produced high amounts of biomass and carotenoids under aeration with additional CO2 and were therefore suitable in biotechnology.

Remediation of Chromium-Contaminated Soil Based on Bacillus cereus WHX-1 Immobilized on Biochar: Cr(VI) Transformation and Functional Microbial Enrichment

Microorganisms are applied to remediate chromium (Cr)-contaminated soil extensively. Nevertheless, the microbial loss and growth inhibition in the soil environment restrain the application of this technology. In this study, a Cr(VI)-reducing strain named Bacillus cereus WHX-1 was screened, and the microbial aggregates system was established via immobilizing the strain on Enteromorpha prolifera biochar to enhance the Cr(VI)-reducing activity of this strain. The mechanism of the system on Cr(VI) transformation in Cr-contaminated soil was illuminated. Pot experiments indicated that the microbial aggregates system improved the physicochemical characteristics of Cr-contaminated soil obviously by increasing organic carbon content and cation exchange capacity, as well as decreasing redox potential and bulk density of soil. Moreover, 94.22% of Cr(VI) was transformed into Cr(III) in the pot, and the content of residue fraction Cr increased by 63.38% compared with control check (CK). Correspondingly, the physiological property of Ryegrass planted on the Cr-contaminated soil was improved markedly and the main Cr(VI)-reducing microbes, Bacillus spp., were enriched in the soil with a relative abundance of 28.43% in the microbial aggregates system. Considering more active sites of biochar for microbial aggregation, it was inferred that B. cereus WHX-1 could be immobilized by E. prolifera biochar, and more Cr(VI) was transformed into residue fraction. Cr stress was decreased and the growth of plants was enhanced. This study would provide a new perspective for Cr-contaminated soil remediation.

Secondary Metabolite Differences between Naturally Grown and Conventional Coarse Green Tea

Crop culture conditions are one of the important interfaces between food, the environment, and health, and an essential research area for maintaining social-ecological integrity. In recent years, it has been reported that the difference in culture conditions between monoculture with external inputs (in cultura) and self-organized ecological niches (in natura) is significant for the resulting physiological property of plants. It has also been suggested that there exist metabolic proxies in various foods that can separate these two culture conditions, which does not depend on a single component but on the distribution of various compounds. However, little has been studied in a time series of replicated production to quantify the reproducibility of these metabolomic features associated with culture conditions. In this study, we obtained metabolome data of coarse green tea (Camellia sinensis) grown in the same region in Japan under both in cultura and in natura culture conditions over the course of six years, and constructed a list of multiple components that separated the effects of culture conditions by statistical analysis, and estimated the metabolic functions of the compounds that contributed to the separation. The results suggest that naturally grown samples are rich in allelochemicals, such as phytochemicals, alkaloids, phenylpropanoids, steroids, as well as the compounds related to microorganisms and vitamin B6 that imply the interactions with the soil microbiome. The estimated physiological functions of the distinctive compounds suggest that the in natura crop production is not only beneficial with known properties of maintaining ecosystem health such as soil functions and pathogen control, but also for the augmentation of the plant secondary metabolites that support long-term health protective effects.

Highly Cross-linked Starch and Modified Cellulose as Dietary Fibers, and their Acclimation Effect on Hydrogen Excretion in Rats

Background: Highly cross-linked phosphate starch (HCPS) and modified cellulose (MC) were newly developed and modified dietary fiber materials to prevent lifestyle-related diseases. Objective: We investigated the physiological property of HCPS and MC to be a dietary fiber. Methods: HCPS was made from tapioca starch by polymerization in the presence of 0.5% phosphoric acid, and MC was made from cellulose, maltodextrin and karaya gum by high-speed mixing. In the present study, rats were raised on a diet containing 10% or 15% HCPS, or 10% MC for four weeks, and physical effects such as growth, organ weights, blood biomedical parameters, fecal weight, and hydrogen excretion were recorded. Results: Growth was normal among all groups, and there was no significant difference in total body weight gain. Some organ weights including the adipose tissues differed slightly among groups, but no difference based on diet composition was observed. Blood biomedical parameters were normal and not significantly different among groups. Cecum tissue and content weights were significantly greater in the 15% HCPS, 10% MC, and 10% fructooligosaccharide (FOS) groups than in the control group, and fecal weight was significantly increased in the 10% and 15% HCPS, and 10% MC groups compared with the control group. Hydrogen excretion over 24 h was negligible when HCPS was administered orally to rats non-acclimatized to HCPS but increased significantly in rats acclimatized to 10% HCPS diet for one week. Conclusion: We conclude that both HCPS and MC could be suitable for use as low energy bulking materials.

Comparative Study of Ripening Related Gene Expression and Postharvest Physiological Changes between Astringent and Nonastringent Persimmon Cultivars

‘Mopan’ persimmon (Diospyros kaki Thunb.) is a traditional astringent cultivar of persimmon and ‘Yoho’ persimmon (D. kaki) is a newly introduced Japanese nonastringent type of cultivar in northern China. Studies were conducted to investigate the physiological changes and expression of ripening-related genes in the postharvest process at different periods under the effects of endogenous ethylene in both cultivars. Persimmons were harvested and stored under room temperature for 20 days. An analysis of physiological changes showed significant differences between the two cultivars. Total soluble solids declined in ‘Mopan’ fruit, whereas those in ‘Yoho’ fruit increased during storage. Firmness, color, index of absorbance difference, total and soluble tannin contents, ethylene production, and respiration rates showed the same trend, but these values vary by cultivar. ‘Mopan’ fruit softened rapidly after harvest and attained edible quality in 20 days, with an increased rate of softening accompanied by increased expression of ripening-related genes. In contract, ‘Yoho’ fruit softening occurred slowly and did not soften even after 20 days, with minimal accumulation of the ripening-related genes. The information obtained from this study demonstrates that cell wall-hydrolyzing enzymes, the de-astringent process, and endogenous ethylene have critical roles in postharvest ripening, gene expression, and physiological property changes of ‘Mopan’ and ‘Yoho’ persimmon fruit during storage.

The Correlation and Regression Analysis of The Growth and Physiological Parameters: How Paclobutrazol Increases Bulb Yield on Three Cultivars of True Shallot Seed

<p>True Shallot Seed (TSS) is a planting material for shallots in the forms of seeds. It shows a visual appearance of the fresh green shoot even though in the harvest season. This condition indicates that TSS still has potential assimilates which should be optimized for bulbs formation. Paclobutrazol is increasing assimilate translocation from source to sink by activating the sucrose transporter enzyme and changing the phytohormones balance. The study aimed to find out how paclobutrazol increased bulb yield on TSS by analyzing the closeness in the relationship between and the influence of physiological property variables and growth analysis. The study was conducted at Gadjah Mada University experimental field, Yogyakarta, from September to November 2017. It was arranged in a Randomized Complete Block Design with three replications. The first factor included the paclobutrazol concentration (0, 15, 30 and 45 mg L^-1), while the second one included TSS cultivars (Tuk Tuk, Sanren and Lokananta). Correlation and regression were used in the data analysis. The results revealed that paclobutrazol significantly affected the physiological properties and the growth of TSS, instead of cultivars. Regression analysis showed that the effect of the concentration of the applied paclobutrazol formed quadratic pattern, where most observed variables had a positive correlation with shallot productivity. Paclobutrazol increased bulb yield by maintaining shoot biomass duration (SBD) and chlorophyll content which had a positive and linear effect on plant growth rate (PGR). The PGR might increase bulb yield per planting hole and indirectly increase its productivity. Paclobutrazol application at 15-30 mg L^-1 could be used to improve bulb yield in TSS.</p>