Increasing Sucrose Concentration Research Articles

Potato E3 ubiquitin ligase StRFP1 positively regulates late blight resistance by degrading sugar transporters StSWEET10c and StSWEET11.

Potato (Solanum tuberosum) is the fourth largest food crop in the world. Late blight, caused by oomycete Phytophthora infestans, is the most devastating disease threatening potato production. Previous research has shown that StRFP1, a potato Arabidopsis Tóxicos en Levadura (ATL) family protein, positively regulates late blight resistance via its E3 ligase activity. However, the underlying mechanism is unknown. Here, we reveal that StRFP1 is associated with the plasma membrane (PM) and undergoes constitutive endocytic trafficking. Its PM localization is essential for inhibiting P. infestans colonization. Through in vivo and in vitro assays, we investigated that StRFP1 interacts with two sugar transporters StSWEET10c and StSWEET11 at the PM. Overexpression (OE) of StSWEET10c or StSWEET11 enhances P. infestans colonization. Both StSWEET10c and StSWEET11 exhibit sucrose transport ability in yeast, and OE of StSWEET10c leads to an increased sucrose content in the apoplastic fluid of potato leaves. StRFP1 ubiquitinates StSWEET10c and StSWEET11 to promote their degradation. We illustrate a novel mechanism by which a potato ATL protein enhances disease resistance by degrading susceptibility (S) factors, such as Sugars Will Eventually be Exported Transporters (SWEETs). This offers a potential strategy for improving disease resistance by utilizing host positive immune regulators to neutralize S factors.

Impact of reduced sucrose content on processed cheese: sensory, textural, and storage stability analysis

The present study examines the impact of varying sucrose concentrations (12%, 6%, and 0%) on the sensory qualities and storage stability of processed cheese. Our findings reveal that sucrose is crucial for enhancing color depth, modulating flavor, and improving texture. Specifically, higher sucrose levels impart a caramel color, increase sweetness, and maintain a harmonious balance between salty and sour tastes, thereby mitigating the intensification of unwanted flavors (P<0.05). Furthermore, sucrose acts as a structural element that bolsters viscoelastic properties and prolongs storage stability; increased sucrose content slows flavor degradation and preserves textural consistency over time. While reductions in sucrose do not significantly compromise the texture of fresh samples (P>0.05), they necessitate adjustments in flavor profiles. This research highlights the essential role of sucrose in processed cheese and sets the stage for further studies on sugar reduction strategies and the potential use of alternative fillers, marking a significant step forward in the development of processed cheese products.

Low Nitrogen Input Mitigates Quantitative but Not Qualitative Reconfiguration of Leaf Primary Metabolism in Brassica napus L. Subjected to Drought and Rehydration.

In the context of climate change and the reduction of mineral nitrogen (N) inputs applied to the field, winter oilseed rape (WOSR) will have to cope with low-N conditions combined with water limitation periods. Since these stresses can significantly reduce seed yield and seed quality, maintaining WOSR productivity under a wide range of growth conditions represents a major goal for crop improvement. N metabolism plays a pivotal role during the metabolic acclimation to drought in Brassica species by supporting the accumulation of osmoprotective compounds and the source-to-sink remobilization of nutrients. Thus, N deficiency could have detrimental effects on the acclimation of WOSR to drought. Here, we took advantage of a previously established experiment to evaluate the metabolic acclimation of WOSR during 14 days of drought, followed by 8 days of rehydration under high- or low-N fertilization regimes. For this purpose, we selected three leaf ranks exhibiting contrasted sink/source status to perform absolute quantification of plant central metabolites. Besides the well-described accumulation of proline, we observed contrasted accumulations of some "respiratory" amino acids (branched-chain amino acids, lysineand tyrosine) in response to drought under high- and low-N conditions. Drought also induced an increase in sucrose content in sink leaves combined with a decrease in source leaves. N deficiency strongly decreased the levels of major amino acids and subsequently the metabolic response to drought. The drought-rehydration sequence identified proline, phenylalanine, and tryptophan as valuable metabolic indicators of WOSR water status for sink leaves. The results were discussed with respect to the metabolic origin of sucrose and some amino acids in sink leaves and the impact of drought on source-to-sink remobilization processes depending on N nutrition status. Overall, this study identified major metabolic signatures reflecting a similar response of oilseed rape to drought under low- and high-N conditions.

Effect of NaCl, CaCl2, and sucrose on the rheological properties of agar from Gracilaria in Vietnam

Agar is a polysaccharide extracted mainly from Gracilaria. Agar is widely used in the food industry as a viscous agent, thickness, emulsifier or food stabiliser. The presence of NaCl, CaCl2 or sucrose influences in sol-gel transition, viscosity of the agar solution or gel strength of the agar. Agar forms a gel at high concentration or lower one if there is the presence of NaCl, CaCl2 or sucrose. Gelling temperature (Tg) of agar solution at 0.2 wt% increasing at 36, 36 or 38°C upon addition of 300 mM NaCl, 100 mM CaCl2, or 30% sucrose, respectively. The viscosity of the 0.2% agar solution increased insignificantly when the ionic strength was below 100 mM, but increased sharply above 100 mM. The gel strength increases with added NaCl, CaCl2 up to 100 mM, 30 mM, respectively; then they drop slightly at higher concentrations of NaCl, CaCl2. Meanwhile, the viscosity of agar solution only increases at sucrose concentrations above 10%. Gel strength increased with increasing sucrose concentration, being 1.2 to 1.8 times higher if 30% sucrose was added.

Copper ion sorption ability of Alternaria alternata (Fr.) Keissl. and Fusarium oxysporum Schltdl. micromycetes

Our analysis of metabolic and ecological features of fungi indicates a high bioremediation potential of fungal mycelium. The relevance of the problems solved in this work is conditioned by insufficiently studied mechanisms and conditions of micromycetal activity on heavy metal detoxication. The effect of copper on the development of two micromycete species, namely, melanised Alternaria alternata (Fr.) Keissl., 1912 and hyaline Fusarium oxysporum Schltdl., 1824 cultivated on Czapek agar (with 2 or 3% sucrose) was compared; the ability of mycelium to sorb copper cations when grown in a liquid culture with 0, 0.05, 0.1, 0.25, and 0.5 mg Cu2+ / L was evaluated. F. oxysporum had noticeable advantages in terms of growth rate, tolerance, conidia production on medium with Cu2+. The effective concentration of copper (EC50), indicating the resistance of the fungus, increased for F. oxysporum by 1.5 times with increasing sucrose content in the medium. The melanised culture of A. alternata was superior to F. oxysporum in terms of sorption capacity. The percentage of Cu2+ extraction by fungal mycelium from the medium reached 40% in the case of F. oxysporum and twice as much in the case of A. alternata . The vast majority of copper was sorbed by the cell walls of hyphae and washed away by water. A small amount (a maximum of 0.16 µg Cu2+ /g dry mycelium of A. alternate ) penetrated inside the mycelial cells. F. oxysporum, which had no intracellular protective melanins, accumulated Cu2+ (2 to 14 times) less. The results show that the mechanisms of resistance to Cu2+ and sorption are different in the studied species: in Fusarium they are determined mainly by the barrier functions of hyphae cell walls, while in Alternaria melanin plays a significant role in protection against Cu toxic action.

Transcriptome scale analysis to decode the differential sucrose accumulation mechanisms in sugarcane under the effect of gibberellin.

In the present study, we analyzed GA3 (gibberellin)-treated sugarcane samples at the transcriptomic level to elucidate the differential expression of genes that influence sucrose accumulation. Previous research has suggested that GA3 application can potentially delay sink saturation by enhancing sink strength and demand, enabling the accommodation of more sucrose. To investigate the potential role of GA-induced modification of sink capacity in promoting higher sucrose accumulation, we sought to unravel the differential expression of transcripts and analyze their functional annotation. Several genes homologous to the sugar-phosphate/phosphate translocator, UTP-glucose-1-phosphate uridylyltransferase, and V-ATPases (vacuolar-type H+ ATPase) were identified as potentially associated with the increased sucrose content observed. A differentially expressed transcript was found to be identical to the mRNA of an unknown protein. Homology-based bioinformatics analysis suggested it to be a hydrolase enzyme, which could potentially act as a stimulator of sucrose buildup. The database of differentially expressed transcripts obtained in this study under the influence of GA3 represents a valuable addition to the sugarcane transcriptomics and functional genomics knowledge base.

Detection of two homologous major QTLs and development of diagnostic molecular markers for sucrose content in peanut.

We identified two stable and homologous major QTLs for sucrose content in peanut, and developed breeder-friendly molecular markers for marker-assisted selection breeding. Sucrose content is a crucial quality trait for edible peanuts, and increasing sucrose content is a key breeding objective. However, the genetic basis of sucrose content in peanut remains unclear, and major quantitative trait loci (QTLs) for sucrose content have yet to be identified. In this study, a high-density genetic map was constructed based on whole-genome re-sequencing data from a peanut RIL population. This map consisted of 2,042 bins and 24,142 SNP markers, making it one of the most comprehensive maps to date in terms of marker density. Two major QTLs (qSCA06.2 and qSCB06.2) were identified, explaining 31.41% and 24.13% of the phenotypic variance, respectively. Notably, these two QTLs were located in homologous genomic regions between the A and B subgenomes. The elite allele of qSCA06.2 was exclusive to Valencia-type, while the elite allele of qSCB06.2 existed in other peanut types. Importantly, the distribution of alleles from two homologous QTLs in the RIL population and diverse germplasm accessions consistently demonstrated that only the combination of elite allelic genotypes from both QTLs/genes resulted in a significantly dominant phenotype, accompanied by a substantial increase in sucrose content. The newly developed diagnostic markers for these QTLs were confirmed to be reliable and could facilitate future breeding efforts to enhance sucrose content using marker-assisted selection techniques. Overall, this study highlights the co-regulation of sucrose content by two major homologous QTLs/genes and provides valuable insights into the genetic basis of sucrose in peanuts.

Cationic Disorder and Surface Effects on the Magnetic Properties of Co3O4$\left(\text{Co}\right)_{3} \left(\text{O}\right)_{4}$ Nanoparticles Synthesized by Co‐Precipitation with Addition of Sucrose

Herein, the effect of adding sucrose chelating agent on the structural and magnetic properties of single‐phase Co3O4 nanoparticles is examined. The samples are obtained using coprecipitation with varying concentrations of sucrose. The X‐ray diffraction data and the scanning electron microscopy and transmission electron microscopy images indicate that the average particle size, their shape, and size distribution depend on the sucrose concentration. The smallest size obtained is around 6 nm for the sample grown with 0.32 mol L−1 of sucrose. Magnetic measurements as a function of magnetic field and temperature indicate that the samples exhibit superparamagnetic behavior below 10 K, and the peak in susceptibility decreases with increasing sucrose concentration, reaching a minimum value of 4.5 K for the sample grown with 0.32 mol L−1 of sucrose. After subtracting the high‐field linear contribution, likely attributed to superparamagnetism, saturation in the M vs. H curves measured at T = 2 K is observed. The saturation is approximately 1.2 emu g−1 for all samples. Since bulk Co3O4 is expected to be antiferromagnetic at T = 40 K, this value of magnetization may be linked to the degree of cationic disorder in the occupation of and ions between A and B sites.

The unequal functional redundancy of Arabidopsis INCURVATA11 and CUPULIFORMIS2 is not dependent on genetic background.

The paralogous genes INCURVATA11 (ICU11) and CUPULIFORMIS2 (CP2) encode components of the epigenetic machinery in Arabidopsis and belong to the 2-oxoglutarate and Fe (II)-dependent dioxygenase superfamily. We previously inferred unequal functional redundancy between ICU11 and CP2 from a study of the synergistic phenotypes of the double mutant and sesquimutant combinations of icu11 and cp2 mutations, although they represented mixed genetic backgrounds. To avoid potential confounding effects arising from different genetic backgrounds, we generated the icu11-5 and icu11-6 mutants via CRISPR/Cas genome editing in the Col-0 background and crossed them to cp2 mutants in Col-0. The resulting mutants exhibited a postembryonic-lethal phenotype reminiscent of strong embryonic flower (emf) mutants. Double mutants involving icu11-5 and mutations affecting epigenetic machinery components displayed synergistic phenotypes, whereas cp2-3 did not besides icu11-5. Our results confirmed the unequal functional redundancy between ICU11 and CP2 and demonstrated that it is not allele or genetic background specific. An increase in sucrose content in the culture medium partially rescued the post-germinative lethality of icu11 cp2 double mutants and sesquimutants, facilitating the study of their morphological phenotypes throughout their life cycle, which include floral organ homeotic transformations. We thus established that the ICU11-CP2 module is required for proper flower organ identity.

Application of D Cryo-Plate Technique for The Cryopreservation of In Vitro-grown Shoot Tips of Tarenaya Spinosa (Cleomaceae)

BACKGROUND: Tarenaya spinosa is a medicinal species used for treating respiratory and inflammatory diseases. Various biotechnological studies have been developed for in vitro establishment of plants and long-term conservation of this species. Objective: This study aimed to establish a new cryopreservation protocol using the D cryo-plate technique for in vitro-grown shoot tips of T. spinosa. MATERIALS AND METHODS: Different steps of the cryopreservation procedure were evaluated in this work: preculture; sucrose concentration of calcium alginate gel; concentration and time of exposure to osmoprotective loading solution; time of exposure to silica gel; and regrowth on recovery medium. RESULTS: The optimal procedure included preculture with increasing sucrose concentration (from 0.25 to 0.50 M), encapsulation and dehydration over silica-gel for 60 min. Increasing sucrose concentration in the loading solution or exposure duration had a negative effect on recovery of cryopreserved shoot tips. However, the association of calcium alginate gel enriched with 0.6 M sucrose with post-rewarming culture with BAP for 2 weeks resulted in the most efficient cryopreservation protocol (76% survival and 70% shoot recovery). CONCLUSION: The plants developed after cryopreservation maintained their in vitro multiplication capacity and demonstrated the efficiency of long-term conservation by D cryo-plate technique for T. spinosa.

Expression of sucrose metabolizing enzymes in different sugarcane varieties under progressive heat stress.

Studying the thermal stress effect on sucrose-metabolizing enzymes in sugarcane is of great importance for understanding acclimation to thermal stress. In this study, two varieties, S2003-US-633 and SPF-238, were grown at three different temperatures ( ± 2°C): 30°C as a control, 45°C for various episodes of high temperature treatments and recovery conditions at 24, 48 and 72 hours. Data showed that reducing sugar content increased until the grand growth stage but sharply declined at the maturity stage in both cultivars. On the other hand, sucrose is enhanced only at the maturity stage. The expression of all invertase isozymes declined prominently; however, the expression of SPS was high at the maturity stage. Hence, the sucrose accumulation in mature cane was due to increased SPS activity while decreased invertase isozymes (vacuolar, cytoplasmic and cell wall) activities at maturity stage in both cultivars. Heat shock decreased the sucrose metabolizing enzymes, sucrose content and sugar recovery rate in both cultivars. In contrast, heat-shock treatments induced maximum proline, MDA, H2O2 and EC in both cultivars. Notably, this is the first report of diverse invertase isozyme molecular weight proteins, such as those with 67, 134 and 160 kDa, produced under heat stress, suggesting that these enzymes have varied activities at different developmental stages. Overall, S2003-US-633 performs better than the cultivar SPF-238 under heat stress conditions at all development stages, with increased sucrose content, enzyme expression, proline and sugar recovery rate. This work will provide a new avenue regarding sugarcane molecular breeding programs with respect to thermal stress.

Green waste-derived compost (GWC) alleviates drought stress and promotes sugar beet productivity and biofortification

ABSTRACT Green waste-derived compost (GWC) is a valuable soil amendment for improving soil organic matter and decreasing waste products and potential pollutants. The study was carried out to evaluate the effect of GWC application on the yield and quality of sugar beet under deficit irrigation conditions using different irrigation systems. A field experiment was conducted using the commercial sugar beet variety Gazelle in sandy soil. Two doses (0 and 14 t ha−1) of GWC were applied to the soil. Three water deficiency levels (60, 80 and 100% of the soil field capacity) under either drip and sprinkler irrigation systems were applied. The application of 14 ton ha−1 of GWC resulted in the highest root and recoverable sugar yields, especially under the well-irrigated conditions under drip irrigation. Sugar beet root biofortification and juice quality were also significantly improved under drip irrigation in response to the application of 14 ton ha−1 of GWC by increasing sucrose content, quality index (Qz)% and recoverable sugar (RS)%. The application of GWC under drip irrigation enhanced water use efficiency for root (WUERY) and recoverable sugar yields (WUERSY), in particular under drip irrigation and water deficit conditions (60% of the soil field capacity). The soil physicochemical properties were significantly improved in response to the application of GWC. GWC application promoted the yield and biofortification of sugar beet by improving the soil physiochemical properties, and nutrient mobilization and uptake. The application of GWC is essential for sustainable sugar beet production and efficient irrigation water use in sandy soils.

Overexpressing Ugp1 promotes phosphate uptake and accumulation in rice (Oryza sativa)

Plant responses to phosphate (Pi) starvation stress involve an array of adaptive strategies including enhanced accumulation and shoot-to-root transport of carbohydrates required for activating the plant Pi starvation signaling. However, the contribution of carbohydrate biosynthesis genes to maintaining phosphorus (P) homeostasis remains unknown, and the functional characterization of sugar metabolism genes is often impeded or compromised due to the loss of fertility of the null mutants. Here, a highly expressed gene encoding UDP-glucose pyrophosphorylase in rice (Oryza sativa), Ugp1, was functionally characterized. Ugp1 was transcriptionally induced in leaf blades by Pi starvation. As a link between sucrose (Suc) and P, we assumed that overexpression of Upg1 would alter the Suc concentration. Given that Suc is a signaling molecule, such concentration changes would affect the P deficiency signal transduction, thereby altering the homeostasis of endogenous P. The results showed that, overexpression of Ugp1 decreased plant biomass, increased sucrose content, and promoted Pi accumulation. The elevated Pi accumulation in Ugp1-OX plants was accompanied by the up-regulation of Pi-starvation-induced genes. Taken together, these results demonstrate that Ugp1 is a positive regulator of sucrose accumulation, and is required for maintaining P homeostasis in rice. Ugp1 thus represents a novel entry point to dissect the mechanisms underlying the carbon-P crosstalk.

Quality and mass transport properties of sugar beet roots under short duration, high airflow post-harvest storage

Active ventilation of stored sugar beet roots is used to control system temperature and slow the loss of quality that occurs with plant respiration and the growth of pathogens. Ventilation can at the same time increase rates of dehydration and dehydration related stresses of the stored sugar beet roots. Recent research into the use of forced ventilation to modify temperature in in-field sugar beet root stores has suggested that a controlled dehydration of roots could lead to improvements in quality. This work aimed to investigate the impacts to sugar beet root quality from short-term, high volume airflow during post-harvest storage. A modified environment experimental setup was developed. The experiment tested four airflow rates over three levels of ventilation duration, with the longest duration being seven days. Air temperature and relative humidity was constant within each seven day run, but varied between runs. Results showed that a mean weight loss of 11.7% with a corresponding increase in sucrose content of 13.2% was achieved at the highest airflow rate and ventilation duration. These changes in quality were a result of the transfer of water from the sugar beet roots. No reduction in total sucrose or other quality parameters was observed. The dependence of the rate of water transfer from the roots on airflow rate was quantified as the convective mass transfer coefficient. Estimates are given and cross-validated using dimensional analysis.

Coordinated regulation of sucrose and lignin metabolism for arrested silk elongation under drought stress in maize

The delay in silking due to drought stress generates a greater anthesis-silking interval in maize, causing compromised kernel set and thus catastrophic loss of grain yield, which is primarily attributed to the lower silk elongation. However, few studies are done in the understanding of the physiochemical and molecular mechanism that regulate silk elongation in response to drought stress. Thus, a field experiment was conducted to examine silk transcriptomic and metabolomic responses to drought stress using the maize cultivar of AN591. A total of 757 differently expressed genes (DEGs) and 80 differently expressed metabolites (DEMs) were identified in maize silk grown in the drought stress treatment compared to the control treatment. These DEGs and DEMs were enriched in 191 and 36 Kyoto Encyclopedia of genes and genomes (KEGG) pathways, respectively, most being associated with primary and secondary metabolism. Starch and sucrose metabolism (SSM) pathway in primary metabolism and phenylpropanoid biosynthesis (PB) pathway in secondary metabolism were identified in common in both transcriptome and metabolome. Most of DEGs in the SSM pathway were increased in expression, while the DEM were decreased in expression. Conversely, most of DEGs in the PB pathway were decreased in expression, while DEMs were increased in expression. This could be explained by the negative correlation between DEGs and DEMs. In the SSM pathway, there was a significant increase in sucrose content, but a significant decrease in fructose and glucose in response to drought stress, which was attributed to the decreased activities in cell wall invertase (CWIN), vacuolar invertase (VIN), and sucrose synthase (SuSy). Silk lignin content in PB pathway was in a significant decrease in drought treatment compared to the control, due to the decreased activity of peroxidase (POD) that is the key enzyme in the final stage of lignin biosynthesis. In conclusion, this study identified key genes or metabolites involved in sucrose and lignin metabolism which appears to be regulating silk elongation response to drought stress.

Development of Photomyxotrophic Culture Protocol of Lemongrass Through Sucrose Concentration Increase and Light Intensity Decrease

Lemongrass (Cymbopogon nardus (L.) Randle) plantlets are interesting to be used as tissue culture-based souvenir. The success of plantlet propagation through photomyxotrophic culture is influenced by several factors, including sucrose concentration and light intensity. The research aimed to analyze the effect of sucrose concentration and light intensity on the growth of lemongrass plantlets. This experimental research used randomized block factorial design with two factors, namely sucrose concentration (0 g/l, 10 g/l, 20 g/l, 30 g/l) and light intensity (2000 lux, 3000 lux, 4000 lux, 5000 lux). The variables observed were some parameters of growth and development of plantlet. The data were analyzed with two-way Analyses of Variance and Duncan Multiple Range Test. The results showed that sucrose concentration had significant effect on the number of shoots and leaves of plantlet. The light intensity and the interaction of both factors had also significant effect on the number of shoots and leaves. The most optimal treatments were sucrose of 20 g/l and light intensity of 3000 lux. The results of this study innovate the tissue culture technique using photomyxotrophic system in order to produce sterile lemongrass plantlets in large quantities.

Climate Variations in the Low-Latitude Plateau Contribute to Different Sugarcane (Saccharum spp.) Yields and Sugar Contents in China.

In China, the main sugarcane (Saccharum spp.) planting areas can be found in the low-latitude plateau (21° N-25° N, 97° E-106° E), which has most of the natural ecological types. However, there is limited information on the climate conditions of this region and their influence on sugarcane yield and sucrose content. Monthly variations in the main climate factors, namely, average air temperature (AAT), average relative humidity (ARH), average rainfall amount (ARA), and average sunshine duration (ASD), from 2000 to 2019 and sugarcane yield and sucrose content of 26 major sugarcane-producing areas from 2001/2002 to 2018/2019 were collected from the low-latitude plateau in Yunnan for studying the impact of climate variations on sugarcane yield and sucrose content. The results showed that AAT in the mid-growth season had a significant positive correlation with sucrose content (p < 0.05), and AAT in the late-growth season had a very significant positive correlation with sucrose content (p < 0.01). ARH in the mid-growth season had a significant positive correlation with sugarcane yield (p < 0.05). ARA in the early-growth season showed a significant positive correlation with sugarcane yield (p < 0.05). ASD in the late-growth season had a significant positive correlation with sugarcane yield (p < 0.05) and sucrose content (p < 0.01). The rainy and humid sugarcane areas were characterized by high ARA and ARH during the entire growth period, low AAT and ASD in the mid-growth season, and low AAT in the late-growth season, contributing to a high sugarcane yield, but not a high sucrose content. The low temperature and sunshine semi-humid sugarcane areas were characterized by the lowest AAT in the early and middle stages of sugarcane growth, less ASD in the early and middle stages, and less ARA in the early and late stages, which are unfavorable for sugarcane yield and sucrose content. The high temperature and humidity sugarcane areas were characterized by higher AAT and ARA, and moderate ASD during the entire growth period, resulting in good sugarcane growth potential and contributing to the sugarcane yield and sucrose content. The semi-humid and multi-sunshine sugarcane areas were characterized by the lowest ARH in the entire growth period, the lowest ARA in the middle and late seasons, and the longest ASD, contributing to an increase in sucrose content. The humid and sunny areas were characterized by the longest ASD and high ARH in the early and late seasons of sugarcane growth and moderate AAT and ARA during the entire growth season, which are beneficial for high sugarcane yield and sucrose content. Overall, these findings suggest that the sugarcane variety layout should be based on the climate type (of which there are five in the plateau), and corresponding cultivation practices should be used to compensate for the climatic conditions in various growth stages.

Sucrose-mediated formation and adhesion strength of Streptococcus mutans biofilms on titanium

Biofilms consist of bacterial cells surrounded by a matrix of extracellular polymeric substance (EPS), which protects the colony from many countermeasures, including antibiotic treatments. Growth and formation of bacterial biofilms are affected by nutrients available in the environment. In the oral cavity, the presence of sucrose affects the growth of Streptococcus mutans that produce acids that erode enamel and form dental caries. Biofilm formation on dental implants commonly leads to severe infections and can restrict osseointegration necessary for the implant to be successful. This work determines the effect of sucrose concentration on biofilm EPS formation and adhesion of Streptococcus mutans, a common oral colonizer, to titanium substrates simulating common dental implants. Biofilm formation and profiles are visualized at high magnification with scanning electron microscopy (SEM). Large mounds and complex structures consisting of bacterial cells and EPS can be seen in biofilms at sucrose concentrations that are favorable for biofilm growth. The laser spallation technique is used to apply stress wave loading to the biofilm, causing the biofilm to delaminate at a critical tensile stress threshold. The critical tensile stress threshold is the adhesion strength. Because laser spallation applies the stress loading to the rear of the substrate, bulk adhesion properties of the biofilm can be determined despite the heterogenous composition and low cohesion strength of the biofilm. Statistical analysis reveals that adhesion strength of biofilms initially increase with increasing sucrose concentration and then decrease as sucrose concentration continues to increase. The adhesion strength of bacterial biofilms to the substrate in this study is compared to the adhesion of osteoblast-like cells to the same substrates published previously. When sucrose is present in the biofilm growth environment, S. mutans adhesion is higher than that of the osteoblast-like cells. Results of this study suggest sucrose-mediated S. mutans biofilms may outcompete osteoblasts in terms of adhesion during osseointegration, which could explain higher rates of peri-implant disease associated with high sugar diets. Further studies demonstrating adhesion differentials between biofilms and cells including co-cultures are needed and motivated by the present work.

Effect of prohexadione-calcium onphotosynthetic and yield parameters in basmati rice (Oryza sativa L.) against lodging stress

Basmati rice cultivators with longer internodes and shallow rooting system are prone to lodging especially during panicle development thus ultimately reducing yield, quality as well as efficiency of mechanical harvesting.Manipulation of GA status both via using exogenous application of GA or use of GA biosynthesis inhibitors or either by genetic alteration are regularly used to optimize plant growth and yields. Keeping this in mind the main objective of the study was to assess the role of Prohexadione-calcium (Pro-Ca) to reduce internode elongation against lodging stress without negatively affecting its productivity. A field experiment was conducted on three cultivars of basmati rice (Punjab Basmati 2, Punjab Basmati 3 and Pusa Basmati 1121) in split plot design at three concentration levels (foliar application) of Pro-Ca @5,10 and 20mg/l at vegetative and anthesis stage. Pro-Ca was found to uphill the concentrations of total chlorophyll (~9%)and Carotenoid(~4%) content in leaves at both vegetative and anthesis stages. An increment in the photosynthetic rate in flag leaf was also recorded in Pro-Ca treated sets in comparison to control, A significant increase in sucrose content in fully expanded leaf at vegetative and flag leaf at anthesis stage was recorded.Plant height significantly decreased in Pro-Ca treated plants and this decrease in height was recorded more with increased concentration of Pro-Ca. The increase in the yield contributing parameters viz., number of spikes/plant and grain/m2might be attributed to the blockage of gibberellins synthesis on account of Pro-Ca applicationin selected basmati rice variety PUSA 1121 by upregulating the photosynthetic rate (2%) andalso increase in sucrose content(2 to 18%).

Influence of atmospheric and vacuum plasma processing on the organic composition of araça-boi (Eugenia stipitata) juice

Cold plasma is a novel non-thermal technology that is still under development. Cold plasma treatment of food products induces a wide range of chemical changes in food compounds, several of which can improve nutritional quality. Understanding the chemical changes caused during plasma treatment is essential to enhance food quality and avoid the formation of undesired compounds. This investigation addressed the influence of two cold plasma technologies, glow discharge plasma and dielectric barrier discharge plasma, on the organic composition of araça-boi (Eugenia stipitata) juice, which is rich in sugars, organic and amino acids. The chemical composition of the juice was assessed by 1H nuclear magnetic resonance coupled with chemometrics. The effects of excitation frequency, processing time, and plasma flow rate were investigated. Glow discharge plasma and dielectric barrier discharge plasma application tended to decrease the concentration of glucose (33%), fructose (31%), malic acid (25%), and amino acids while increasing sucrose content (23%). Overall, plasma processing changed the juices’ alcohol, sugar, and amino acids content, primarily by reducing the concentration of cysteine (33%), alanine (42%), and methionine (43%). However, the dielectric barrier discharge plasma tended to slightly increase the amino acid content (up to 9%) when operating at 200 Hz.