Substrate Supplementation Research Articles

Applicability Analysis of Peanut Addition to Button Mushroom Substrate Supplement Formulation

This study evaluated the agronomic response of Agaricus bisporus strains supplemented with various formulations containing soybean meal and peanut grain residue, which has traces of aflatoxins. Six supplement formulations were developed, starting with 100% soybean meal and no peanuts and gradually increasing peanut inclusion by 10% while proportionally reducing soybean meal until reaching a 50% soybean and 50% peanut ratio. The substrate was produced using the traditional method and supplemented at two points: during inoculation and when adding the cover layer. The strains ABI 22/01 and ABI 22/02 were utilized. After the supplementation and incubation periods in a controlled environment (19 ± 2 °C and 85 ± 5% humidity), the fungus was cultivated. Three production cycles were conducted, evaluating yield, weight, number of mushrooms, biological efficiency, and precocity. The concentrations of aflatoxins in the supplements and mushrooms were determined, along with the nutritional characterization of the substrate and supplements. The inclusion of up to 30% peanuts in the supplement formulation was beneficial for yield, particularly for ABI 22/01. The formulation with 80% soybean meal and 20% peanuts resulted in a 53% yield increase compared to the control. Traces of aflatoxin were found in the supplement but not in the mushrooms.

Enhancing tomato plants' tolerance to combined heat and salt stress – The role of arbuscular mycorrhizae and biochar

The Mediterranean basin is highly susceptible to climate change, with soil salinization and the increase in average temperatures being two of the main factors affecting crop productivity in this region. Following our previous studies on describing the detrimental effects of heat and salt stress co-exposure on tomato plants, this study aimed to understand if substrate supplementation with a combination of arbuscular mycorrhizal fungi (AMF) and biochar could mitigate the negative consequences of these stresses. Upon 21 days of exposure, stressed tomato plants grown under supplemented substrates showed increased tolerance to heat (42 °C for 4 h/day), salt (100 mM NaCl), and their combination, presenting increased biomass and flowering rate. The beneficial effects of AMF and biochar were associated with a better ionic balance (i.e. lower sodium accumulation and higher uptake of calcium and magnesium) and increased photosynthetic efficiency. Indeed, these plants presented higher chlorophyll content and improved CO2 assimilation rates. Biochemical data further supported that tomato plants grown with AMF and biochar were capable of efficiently modulating their defence pathways, evidenced by the accumulation of proline, ascorbate, and glutathione, coupled with a lower dependency on energy-costly enzymatic antioxidant players. In summary, the obtained data strongly point towards a beneficial role of combined AMF and biochar as sustainable tools to improve plant growth and development under a climate change scenario, where soil salinization and heat peaks often occur together.

Enhancing the plant growth promoting activity of Trichoderma viride biopesticide using substrate supplementation and co-cultivation

Enhancing the plant growth promoting activity of Trichoderma viride biopesticide using substrate supplementation and co-cultivation

Marine microalgae Schizochytrium demonstrates strong production of essential fatty acids in various cultivation conditions, advancing dietary self-sufficiency

IntroductionPolyunsaturated fatty acids (PUFAs) are essential nutrients that humans obtain from their diet, primarily through fish oil consumption. However, fish oil production is no longer sustainable. An alternative approach is to produce PUFAs through marine microalgae. Despite the potential of algae strains to accumulate high concentrations of PUFAs, including essential fatty acids (EFAs), many aspects of PUFA production by microalgae remain unexplored and their current production outputs are frequently suboptimal.MethodsIn this study, we optimized biomass and selected ω-3 PUFAs production in two strains of algae, Schizochytrium marinum AN-4 and Schizochytrium limacinum CO3H. We examined a broad range of cultivation conditions, including pH, temperature, stirring intensity, nutrient concentrations, and their combinations.ResultsWe found that both strains grew well at low pH levels (4.5), which could reduce bacterial contamination and facilitate the use of industrial waste products as substrate supplements. Intensive stirring was necessary for rapid biomass accumulation but caused cell disruption during lipid accumulation. Docosahexaenoic acid (DHA) yield was independent of cultivation temperature within a range of 28–34°C. We also achieved high cell densities (up to 9 g/L) and stable DHA production (average around 0.1 g/L/d) under diverse conditions and nutrient concentrations, with minimal nutrients required for stable production including standard sea salt, glucose or glycerol, and yeast extract.DiscussionOur findings demonstrate the potential of Schizochytrium strains to boost industrial-scale PUFA production and make it more economically viable. Additionally, these results may pave the way for smaller-scale production of essential fatty acids in a domestic setting. The development of a new minimal culturing medium with reduced ionic strength and antibacterial pH could further enhance the feasibility of this approach.

(206) Strategies of Nitric Oxide Augmentation for PDE5 Inhibitors

Abstract Introduction Erectile function and endothelial functions are closely related entities. Nitric oxide NO regulates circulation and microcirculation involved in erection.NO concentration is reduced with aging, diabetes, environment pollution smoking, obesity, inflammation, high prolactin, low testosterone oxidative stress and atherosclerosis. Many of erectile dysfunction patients are PDE5 inhibitor resistant. Strategies to enhance NO expression, can be employed to convert treatment resistant patient into responder. Objective Employ every possible mechanism to augment nitric oxide expression. Greater base line nitric oxide better would be PDE5 inhibitor respose. Methods Internet search was made on various website including pub med, science direct, google scholars using key words like erection, erectile dysfunction, nitric oxide, l arginine, oxidative stress, antioxidant, NOS, endothelial dysfunction, atherosclerosis and etc. This was followed by literature study on given topic. Results Efficacy of PDE 5 inhibitor in ED treatment is 70%. NO concentration decline to 50% by age of 40 and is only 15% at age 60. Humming can increase nasal NO level up to 15 time. Conclusions NO regulates endothelial function, vasodilatation, platelet aggregation inhibition, free radical scavenging, testosterone synthesis and neuronal protection. Study of mechanism of NO production provides, strategies for its enhancement. L arginine, L citrulline, serve as substrate and vitamin C, tetrahydrobiopterin (BH4) act as co factors in production of NO. Endothelial nitric oxide synthase e NOS, neuronal nitric oxide synthase n NOS are major enzymes act involved in synthesis. Oxygen is required for NO synthesis process. Supplementation of substrate and cofactors help increase NO levels. Oxygen availability can be increased through exercise and raising hemoglobin level. Reactive oxygen species ROS convert NO into bioinactive peroxynitrite which itself is ROS. Oxidative stress can cause endothelial nitric oxide synthase uncoupling. Consequently eNOS start producing ROS. This causes oxidation of NOS and as well as of cofactor like BH4 and vitamin C. ROS also increase level of methylarginines. Antioxidant used to neutralize ROS include Co Q10, alpha lipoic acid, flavonoids, bioflavonoids poly phenols, pycnogenol, resveterol, fulvic acid and etc. Second mechanism NO production is from dietary nitrates. Nutritional nitrates are converted into nitrite by oral anaerobic bacteria’s. Nitrate rich foods like beet root or spinach are added to enhance nitrate based NO. Nitric oxide thus produced is used for vasodilatation of penile vessels as well sinuses of corpus cavernousm. Apart from that it inhibits uncoupling of NOS. This support L arginine based mechanism of NO production. Nitroglycerin or minoxidal act as NO donors. These agents can be used locally at glans penis to augment NO availability. Bee breathing is maneuver in which humming sound vibrates nasal sinus increasing NO production up to 15 folds. Inhaled NO act as bronchodilator which increase lung capacity leading to higher blood oxygen concentration. Various NO enhancement strategies thus applied, may convert non responder PDE5 inhibitor to responders. Disclosure No.

Improving the productivity of gibberellic acid by combining small-molecule compounds-based targeting technology and transcriptomics analysis in Fusarium fujikuroi

Gibberellic acid (GA3), produced industrially by Fusarium fujikuroi, stands as a crucial plant growth regulator extensively employed in the agriculture filed while limited understanding of the global metabolic network hinders researchers from conducting rapid targeted modifications. In this study, a small-molecule compounds-based targeting technology was developed to increase GA3 production. Firstly, various small molecules were used to target key nodes of different pathways and the result displayed that supplement of terbinafine improved significantly GA3 accumulation, which reached to 1.08 g/L. Subsequently, lipid and squalene biosynthesis pathway were identified as the key pathways influencing GA3 biosynthesis by transcriptomic analysis. Thus, the strategies including in vivo metabolic engineering modification and in vitro supplementation of lipid substrates were adopted, both contributed to an enhanced GA3 yield. Finally, the engineered strain demonstrated the ability to achieve a GA3 yield of 3.24 g/L in 5 L bioreactor when utilizing WCO as carbon source and feed.

Energy substrate supplementation increases ATP levels and is protective to PD neurons

Alteration of mitochondrial metabolism by various mutations or toxins leads to various neurological conditions. Age-related changes in energy metabolism could also play the role of a trigger for neurodegenerative disorders. Nonetheless, it is not clear if restoration of ATP production or supplementation of brain cells with substrates for energy production could be neuroprotective. Using primary neurons and astrocytes, and neurons with familial forms of neurodegenerative disorders we studied whether various substrates of energy metabolism could improve mitochondrial metabolism and stimulate ATP production, and whether increased ATP levels could protect cells against glutamate excitotoxicity and neurodegeneration. We found that supplementation of neurons with several substrates, or combination thereof, for the TCA cycle and cellular respiration, and oxidative phosphorylation resulted in an increase in mitochondrial NADH level and in mitochondrial membrane potential and led to an increased level of ATP in neurons and astrocytes. Subsequently, these cells were protected against energy deprivation during ischemia or glutamate excitotoxicity. Provision of substrates for energy metabolism to cells with familial forms of Parkinson's disease also prevented triggering of cell death. Thus, restoration of energy metabolism and increase of ATP production can play neuroprotective role in neurodegeneration. A combination of a succinate salt of choline and nicotinamide provided the best results.

Nitrospira dominant pin-point flocs with granule-like settleability in stirred tank reactors with oxic/hypoxic/oxic zones.

The characteristics of biomass and microbial community dynamics, in relation to autotrophic nitrification, were studied in two 20 L stirred tank reactors (STR) with oxic/hypoxic/oxic zones. The bioreactors were fed with synthetic wastewater with stepwise increasing ammonia concentrations (50-200 N mg/L) without organic substrate in the first phase (autotrophic phase) for 35 days (R1) and 15 days (R2), followed by a heterotrophic phase (with supplementation of organic substrate). The settling properties of the biomass, represented by pin-point flocs, gradually improved in both reactors during the autotrophic phase. The pin-point flocs of R1 exhibited granule-like settling properties. The SVI30 in RI gradually improved to 29 mL/g MLSS, and the corresponding SVI30/ SVI10 gradually improved to 0.88 during the autotrophic phase. The settling properties of the biomass deteriorated in both bioreactors during the heterotrophic phase. The protein to polysaccharide ratio (PN:PS ratio) gradually increased in the extracted EPS (in both, loosely bound (LB) and tightly bound (TB) EPS) during the autotrophic phase, in both bioreactors. The TB:LB EPS ratio was higher when the pin-point flocs of R1 showed granule-like settling properties, followed by a decline in TB:LB EPS ratio during the heterotrophic phase. A combination of molecular approaches (droplet digital-PCR (dd-PCR) and 16S rRNA gene sequencing) revealed that Nitrospira were the predominant nitrifying bacteria in the pin-point flocs that show granular sludge-like settling properties during autotrophic phase in R1. Comammox Nitrospira was the dominant ammonia oxidizer in seed biomass and at low ammonia concentrations in both bioreactors. The relative abundance of canonical ammonia-oxidizing bacteria increased with an increase in influent-ammonia concentrations.

Application of Substrate Supplements to the Yield Oyster Mushrooms (Pleurotus ostreatus var. florida)

Oyster mushroom is an edible, saprophytic, and lignocellulolytic fungi. The folic acid present in oyster mushrooms helps to cure anemia. Oyster mushroom contains most of the mineral salts necessary for the human body. The amount of niacin is almost ten times higher than that of any other vegetables.
 In this study, oyster mushroom (Pleurotus ostreatus var. florida (Jacq: Fr) Kummer) were grown with various substrate additions to determine their effects on yield. We ran tests to know different supplements affected the yield and growth of mushrooms. The substrate, composed primarily of sawdust and straw, served as the growth medium. The research encompassed controlled environmental conditions, including temperature, humidity, and light, over a defined study period. Our findings revealed significant variations in mushroom yield and growth parameters across the different supplement treatments. The best supplements to the substrate treatment combination were observed T14- Wheat Straw (60%), + Rice Straw (34 %) + Gram Flour (2% of the substrate) (451.69g) and (452.33g) followed by T11 – Rice Straw (60%), + Wheat Straw (34 %) + Maize Flour (2% of the substrate) which increased the yield of oyster mushroom, while others exhibited nuanced effects on mushroom quality. Statistical analyses supported these observations. The implications of this research extend to both commercial and amateur mushroom cultivators. Understanding the influence of substrate supplements on Oyster mushroom growth can lead to more efficient and cost-effective cultivation practices. By optimizing substrate composition, growers can enhance yields, potentially increasing profitability and sustainability in the mushroom industry. This study also highlights the need for further exploration in the field, including investigations into the specific mechanisms underlying supplement-substrate interactions.

Protein modification by short-chain fatty acid metabolites in sepsis: a comprehensive review.

Sepsis is a major life-threatening syndrome of organ dysfunction caused by a dysregulated host response due to infection. Dysregulated immunometabolism is fundamental to the onset of sepsis. Particularly, short-chain fatty acids (SCFAs) are gut microbes derived metabolites serving to drive the communication between gut microbes and the immune system, thereby exerting a profound influence on the pathophysiology of sepsis. Protein post-translational modifications (PTMs) have emerged as key players in shaping protein function, offering novel insights into the intricate connections between metabolism and phenotype regulation that characterize sepsis. Accumulating evidence from recent studies suggests that SCFAs can mediate various PTM-dependent mechanisms, modulating protein activity and influencing cellular signaling events in sepsis. This comprehensive review discusses the roles of SCFAs metabolism in sepsis associated inflammatory and immunosuppressive disorders while highlights recent advancements in SCFAs-mediated lysine acylation modifications, such as substrate supplement and enzyme regulation, which may provide new pharmacological targets for the treatment of sepsis.

Comammox plays a functionally important role in the nitrification of rice paddy soil with different nitrogen fertilization levels

Chemoautotrophic ammonia-oxidizing bacteria (AOB), ammonia-oxidizing archaea (AOA), and the recently discovered complete ammonia oxidizers (comammox) catalyze ammonia oxidation; however, quantifying their individual gross ammonia oxidation activities in complex soil ecosystems remains elusive. In this study, we investigated the nitrifying population and community dynamics in response to fertilization in paddy soil under long-term treatment with different urea concentrations (0, 100, 200, and 300 kg N ha−1; designated N0, N100, N200, and N300, respectively). The community structure of nitrifiers, including comammox, was changed by long-term N fertilizers input, which also enhanced AOB abundance and comammox clade A/B abundance ratio, whereas it did not affect AOA abundance. Nevertheless, the microbial population sizes and community compositions remained largely similar following short-term fertilization throughout one rice-growing season. Furthermore, by employing a 15NO3− pool dilution technique in combination with chlorate and 1-octyne inhibition, we conducted a soil microcosm incubation without substrate supplementation to distinguish the relative contribution of comammox to gross ammonia oxidation from those of AOA and AOB. Comammox exhibited higher nitrification activity in soils treated with more N fertilizers, with the contribution increasing from 34 % (N0) to 75 % (N300), although its abundance was not dominant. This could be attributed to the repeated N-based fertilization, which reduced the soil pH, thereby decreasing the soil-free ammonia concentration. In contrast, the contribution of AOA declined from 57 % (N0) to 19 % (N300), while that of AOB only accounted for a minor fraction (<25 %) despite being in high abundance. Altogether, our findings provide evidence that the activity of nitrifying guilds is more valuable than their abundance and provide insights into the potential functional significance of comammox in the nitrification process in rice paddy systems.

Self-triggered thermoelectric nanoheterojunction for cancer catalytic and immunotherapy

The exogenous excitation requirement and electron-hole recombination are the key elements limiting the application of catalytic therapies. Here a tumor microenvironment (TME)-specific self-triggered thermoelectric nanoheterojunction (Bi0.5Sb1.5Te3/CaO2 nanosheets, BST/CaO2 NSs) with self-built-in electric field facilitated charge separation is fabricated. Upon exposure to TME, the CaO2 coating undergoes rapid hydrolysis, releasing Ca2+, H2O2, and heat. The resulting temperature difference on the BST NSs initiates a thermoelectric effect, driving reactive oxygen species production. H2O2 not only serves as a substrate supplement for ROS generation but also dysregulates Ca2+ channels, preventing Ca2+ efflux. This further exacerbates calcium overload-mediated therapy. Additionally, Ca2+ promotes DC maturation and tumor antigen presentation, facilitating immunotherapy. It is worth noting that the CaO2 NP coating hydrolyzes very slowly in normal cells, releasing Ca2+ and O2 without causing any adverse effects. Tumor-specific self-triggered thermoelectric nanoheterojunction combined catalytic therapy, ion interference therapy, and immunotherapy exhibit excellent antitumor performance in female mice.

The NOS/NO System in Renal Programming and Reprogramming.

Nitric oxide (NO) is a gaseous signaling molecule with renoprotective properties. NO can be produced in NO synthase (NOS)-dependent or -independent manners. NO deficiency plays a decisive role in chronic kidney disease (CKD). Kidney development can be affected in response to adverse intrauterine conditions that induce renal programming, thereby raising the risk of developing CKD in adulthood. Conversely, detrimental programming processes could be postponed or halted prior to the onset of CKD by early treatments, namely reprogramming. The current review provides an overview of the NOS/NO research performed in the context of renal programming and reprogramming. NO deficiency has been increasingly found to interact with the different mechanisms behind renal programming, such as oxidative stress, aberrant function of the renin-angiotensin system, disturbed nutrient-sensing mechanisms, dysregulated hydrogen sulfide signaling, and gut microbiota dysbiosis. The supplementation of NOS substrates, the inhibition of asymmetric dimethylarginine (ADMA), the administration of NO donors, and the enhancement of NOS during gestation and lactation have shown beneficial effects against renal programming in preclinical studies. Although human data on maternal NO deficiency and offspring kidney disease are scarce, experimental data indicate that targeting NO could be a promising reprogramming strategy in the setting of renal programming.

Meyerozyma caribbica Isolated from Vinasse-Irrigated Sugarcane Plantation Soil: A Promising Yeast for Ethanol and Xylitol Production in Biorefineries.

The production of fuels and other industrial products from renewable sources has intensified the search for new substrates or for the expansion of the use of substrates already in use, as well as the search for microorganisms with different metabolic capacities. In the present work, we isolated and tested a yeast from the soil of sugarcane irrigated with vinasse, that is, with high mineral content and acidic pH. The strain of Meyerozyma caribbica URM 8365 was able to ferment glucose, but the use of xylose occurred when some oxygenation was provided. However, some fermentation of xylose to ethanol in oxygen limitation also occurs if glucose was present. This strain was able to produce ethanol from molasses substrate with 76% efficiency, showing its tolerance to possible inhibitors. High ethanol production efficiencies were also observed in acidic hydrolysates of each bagasse, sorghum, and cactus pear biomass. Mixtures of these substrates were tested and the best composition was found for the use of excess plant biomass in supplementation of primary substrates. It was also possible to verify the production of xylitol from xylose when the acetic acid concentration is reduced. Finally, the proposed metabolic model allowed calculating how much of the xylose carbon can be directed to the production of ethanol and/or xylitol in the presence of glucose. With this, it is possible to design an industrial plant that combines the production of ethanol and/or xylitol using combinations of primary substrates with hydrolysates of their biomass.

Visible light-driven dual photoelectrode microbial electrosynthesis using BiVO4-RuO2-IrO2 on Ti mesh photoanode and ZIF-67/g-C3N4 on carbon felt photocathode for the efficient reduction of CO2 into acetate

Microbial electrosynthesis (MES) systems integrated with solar energy (photoelectrode-assisted MES) represent an attractive method for the fixation of CO2 through microbial electrochemical processes. In this study, BiVO4-RuO2-IrO2/Ti with long-term stability and corrosion resistance was used as photoanode through the electrophoretic deposition of BiVO4 on RuO2-IrO2/Ti mesh, significantly reducing the charge recombination rate and enhancing the oxygen evolution reaction (OER) ability. Simultaneously, the ZIF-67/g-C3N4 photocathode can significantly increase CO2 absorption and hydrogen production by enhancing electron–hole separation ability under visible light. Consequently, the MES system with the BiVO4-RuO2-IrO2/Ti anode and ZIF-67/g-C3N4 photocathode obtained an acetate yield of 0.46 g/L/d at −0.9 V versus Ag/AgCl within 14 days. This value was 4.6 times that under dark conditions. The solar-to-acetate conversion efficiency was determined to be 1.52%. Furthermore, the MES with dual photoelectrode still obtained an acetate yield of 0.09 g/L/d at −0.6 V versus Ag/AgCl. These results showed that the MES with the BiVO4-RuO2-IrO2/Ti photoanode and ZIF-67/g-C3N4 photocathode reduced OER overpotential, increased electron transport rate, and improved CO2 supply for the simultaneous supplementation of substrates and electrons in MES. This work provides a new strategy for constructing efficient photoelectrodes in MES to achieve highly efficient chemical generation for CO2 transformation under solar light.

Effect of Honey, Palm Oil and NPK Fertilizer on the Growth of Oyster Mushrooms Cultivated on Sawdust

The study was carried out to determine the effect of honey, palm oil and NPK fertilizer on the growth of Pleurotus pulmonarius (Fr.) Quel. and Pleurotus ostreatus (Jack.) Kumm. on Celtis zenkeri Engl. sawdust. Composted sawdust was supplemented with honey, palm oil and NPK fertilizer at 0%, 2%, 4%, 6% and 8% on the dry weight basis and inoculated with 5% spawn. The substrate amended with 4% palm oil was fully colonized by Pleurotus ostreatus and P. pulmonarius after 26.0±2.1 and 32.2±1.3 days, respectively. The mushroom took shorter time (43 days) for primordial emergence at 6% palm oil. Average of 55 fruitbodies of P. ostreatus was harvested from 4% palm oil supplemented sawdust. The best mushroom yield was recorded from 8% palm oil (278.5 ±5.0 g) and 8% honey (270.1±2.7 g). The highest biological efficiency was observed at 8 % palm oil (77.36±1.5 %) and 8 % honey (75.03±2.5 %) for P. ostreatus. The two mushrooms species performed significantly (p=0.05) with palm oil and honey supplementation. The best performance was observed at 6% and 8% supplementation with palm oil and honey. The research has shown that supplementation of sawdust substrate with honey and palm oil at 4 - 8% can be a good formulation for commercial cultivation of oyster mushrooms.

Xylitol biosynthesis enhancement by Candida tropicalis via medium, process parameter optimization, and co-substrate supplementation

The present study examines the impact of nitrogen sources (yeast extract, ammonium sulfate peptone, ammonium nitrate, urea, and sodium nitrate), salt solution (0.5 g/L MgSO4, 0.5 g/L KH2PO4, 0.3 g/L CaCl2), trace elements solution (0.1 g/L CuSO4, 0.1 g/L FeSO4, 0.02 g/L MnCl2, 0.02 g/L ZnSO4), operational parameters (temperature, aeration, agitation, initial pH and xylose concentration) and co- substrate supplementation (glucose, fructose, maltose, sucrose, and glycerol) on xylitol biosynthesis by Candida tropicalis ATCC 13803 using synthetic xylose. The significant medium components were identified using the Plackett Burman design followed by central composite designs to obtain the optimal concentration for the critical medium components in shaker flasks. Subsequently, the effect of operational parameters was examined using the One Factor At a Time method, followed by the impact of five co-substrates on xylitol biosynthesis in a 1 L bioreactor. The optimal media components and process parameters are as follows: peptone: 12.68 g/L, yeast extract: 6.62 g/L, salt solution (0.5 g/L MgSO4, 0.5 g/L KH2PO4, and 0.3 g/L CaCl2): 1.23 X (0.62 g/L, 0.62 g/L, and 0.37 g/L respectively), temperature: 30 °C, pH: 6, agitation: 400 rpm, aeration: 1 vvm, and xylose: 50 g/L. Optimization studies resulted in xylitol yield and productivity of 0.71 ± 0.004 g/g and 1.48 ± 0.018 g/L/h, respectively. Glycerol supplementation (2 g/L) further improved xylitol yield (0.83 ± 0.009 g/g) and productivity (1.87 ± 0.020 g/L/h) by 1.66 and 3.12 folds, respectively, higher than the unoptimized conditions thus exhibiting the potential of C. tropicalis ATCC 13803 being used for commercial xylitol production.

Enriching the endophytic bacterial microbiota of Ginkgo roots.

Bacterial endophytes of Ginkgo roots take part in the secondary metabolic processes of the fossil tree and contribute to plant growth, nutrient uptake, and systemic resistance. However, the diversity of bacterial endophytes in Ginkgo roots is highly underestimated due to the lack of successful isolates and enrichment collections. The resulting culture collection contains 455 unique bacterial isolates representing 8 classes, 20 orders, 42 families, and 67 genera from five phyla: Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria, and Deinococcus-Thermus, using simply modified media (a mixed medium without any additional carbon sources [MM)] and two other mixed media with separately added starch [GM] and supplemented glucose [MSM]). A series of plant growth-promoting endophytes had multiple representatives within the culture collection. Moreover, we investigated the impact of refilling carbon sources on enrichment outcomes. Approximately 77% of the natural community of root-associated endophytes were predicted to have successfully cultivated the possibility based on a comparison of the 16S rRNA gene sequences between the enrichment collections and the Ginkgo root endophyte community. The rare or recalcitrant taxa in the root endosphere were mainly associated with Actinobacteria, Alphaproteobacteria, Blastocatellia, and Ktedonobacteria. By contrast, more operational taxonomic units (OTUs) (0.6% in the root endosphere) became significantly enriched in MM than in GM and MSM. We further found that the bacterial taxa of the root endosphere had strong metabolisms with the representative of aerobic chemoheterotrophy, while the functions of the enrichment collections were represented by the sulfur metabolism. In addition, the co-occurrence network analysis suggested that the substrate supplement could significantly impact bacterial interactions within the enrichment collections. Our results support the fact that it is better to use the enrichment to assess the cultivable potential and the interspecies interaction as well as to increase the detection/isolation of certain bacterial taxa. Taken together, this study will deepen our knowledge of the indoor endophytic culture and provide important insights into the substrate-driven enrichment.

Enhancing volatile fatty acids accumulation through anaerobic co-fermentation of excess sludge and sodium citrate: Divalent cation chelation and carbon source supplement

This work developed an innovative anaerobic co-fermentation strategy of excess sludge to enhance volatile fatty acids (VFAs) production and carbon recovery relying on the sodium citrate (SC) functions of divalent cation bridging impairing and biodegradable substrate supplement. It was demonstrated that SC greatly improved rate constant and equilibrium performances of both sludge hydrolysis and VFAs accumulation, suggesting that the 0.4 g/g SS was the optimum SC dosage. The SC was partly absorbed in sludge solid and chelated structural divalent cations, which greatly facilitated sludge hydrolysis with the SCOD/TCOD of 28.20%. Meanwhile, the residual SC in liquid phase contributed to VFAs bio-generation as carbon substrates. Thereby, the VFAs accumulation was improved to 387.72 mg COD/g VSS in a short-term anaerobic co-fermentation (2 d), approximately 7.64 times higher than that without SC addition. The VFAs were mainly composed by acetate (58.86–81.76%) and propionate (7.97–16.28%). In the whole anaerobic co-fermentation process, remarkable carbon source of 1785.74 mg/L was released. Acetate was the dominant composition in total soluble carbon sources with the percentage of 44.45–83.98%, manifesting the bio-availability of fermentative liquid. In this case, the bio-available carbon recovery rate of 38.04% was achieved. Moreover, mechanism of the enhanced anaerobic co-fermentation was illustrated and the economic benefits were clarified.

Near-Infrared Reflectance Spectroscopy for Quantitative Analysis of Fat and Fatty Acid Content in Living Tenebrio molitor Larvae to Detect the Influence of Substrate on Larval Composition.

Several studies have shown that mealworms (Tenebrio molitor L.) could provide animals and humans with valuable nutrients. Tenebrio molitor larvae were studied to determine whether their rearing diets affected their fat and fatty acid content and to ascertain if it is possible to detect the changes in the larval fat composition using near-infrared reflectance spectroscopy (NIRS). For this reason, a standard control diet (100% wheat bran) and an experimental diet, consisting of wheat bran and the supplementation of a different substrate (coconut flour, flaxseed flour, pea protein flour, rose hip hulls, grape pomace, or hemp protein flour) were used. The results showed lesser weight gain and slower growth rates for larvae raised on diets with a high fat content. A total of eight fatty acids were identified and quantified, where palmitic, oleic, and linoleic acids were the most prevalent and showed a correlation between larval content and their content in the rearing diets. There was a high content of lauric acid (3.2-4.6%), myristic acid (11.4-12.9%), and α-linolenic acid 8.4-13.0%) in mealworm larvae as a result of the high dietary content of these fatty acids. NIR spectra were also influenced by the fat and fatty acid composition, as larval absorbance values differed greatly. The coefficient of the determination of prediction (R2P) was over 0.97, with an RPD value of 8.3 for the fat content, which indicates the high predictive accuracy of the NIR model. Furthermore, it was possible to develop calibration models with great predictive efficiency (R2P = 0.81-0.95, RPD = 2.6-5.6) for all fatty acids, except palmitoleic and stearic acids which had a low predictive power (R2P < 0.5, RPD < 2.0). The detection of fat and fatty acids using NIRS can help insect producers to quickly and easily analyze the nutritional composition of mealworm larvae during the rearing process.