Preparation of S-iron-enriched yeast using siderophores and its effect on iron deficiency anemia in rats

Antianemic Activity, Inhibition of Oxidative Stress, and Iron Supplementation in Mice with Iron-Deficiency Anemia through HG-Hawthorn Pectin-Iron(III) Complexes

In this study, we initially assessed the antioxidant activities of various HG-type hawthorn pectin-iron(III) complexes, which were synthesized in our previous research, utilizing methods such as reducing assay, 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and scavenging, and hydroxyl radical scavenging. The results showed that the antioxidant capacity of the hawthorn pectin iron(III) complexes exhibited a positive correlation with increasing concentrations, ranging from 0.2 to 1.0 mg/mL. Notably, the pectin complex chelated with iron via ultrasonic extraction and de-esterification for 20 min (designated as DU20-Fe) showed the most significant antioxidant activity. Subsequently, DU20-Fe was chosen for in vivo activity assessment in a mouse model of iron-deficiency anemia (IDA). The findings indicated that DU20-Fe significantly enhanced levels of red blood cells (RBC), mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH) content in the mice with IDA. Furthermore, histological analysis of the liver demonstrated that DU20-Fe effectively alleviated liver damage in the IDA mice. These results validate the potential of hawthorn pectin-iron complexes in exhibiting anti-iron-deficiency anemia activity, suggesting that the hawthorn pectin-iron(III) complex may be developed into a bio-polysaccharide-based iron supplement with multiple health benefits.

Investigation of impact of siderophore and process variables on production of iron enriched Saccharomyces boulardii by Plackett-Burman design

The primary cause of anemia worldwide is due to poor diet and iron deficiency. Iron (Fe) enriched yeast can be the most effective way to manage anemia because of the capability for biotransformation of mineral to organic and bioavailable iron. To overcome the low richness of yeast, the use of siderophore as cellular iron carriers is a new approach. In this research, for the first time the potential of siderophore in increasing the Fe enrichment of Saccharomyces boulardii (S. boulardii), which is important because of its probiotic properties and resistance to different stresses, has been investigated to produce of potential iron supplements. For this purpose, siderophore was produced by Pseudomonas aeruginosa (P. aeruginosa). Siderophore impact, along with ten other independent process variables, has been studied on the efficiency of iron biotransformation by the Plackett-Burman design (PBD). The results showed that the highest biotransformation yield was 17.77 mg Fe/g dry cell weight (DCW) in the highest biomass weight of 9 g/l. Iron concentration is the most important variable, with contributions of 46% and 70.79% for biomass weight and biotransformation, respectively, followed by fermentation time, agitation speed, and KH2PO4 concentration. But increasing the level of siderophore and zinc led to a significant negative effect. siderophore inefficiency may be attributed to the absence of membrane receptors for pyoverdine (Pvd) and pyochelin (Pch) siderophores. Also, the steric hindrance of the cell wall mannan, the stickiness and sediment ability of the yeast, can create limitations in the absorption of elements. Such yeast can be used as a potential source of iron even for vegetarians and vegans in the form of medicinal and fortified food products to improve the treatment of anemia. It is recommended that further research be focused on increasing the iron enrichment of yeast by overcoming the structural barrier of the cell wall, investigating factors affecting membrane permeability and iron transport potential of other types of siderophores.

Production of iron-enriched yeast and it's application in the treatment of iron-deficiency anemia

Iron deficiency anemia (IDA) is one of the most serious forms of malnutrition. Wild type strains of Saccharomyces cerevisiae have higher tolerance to inorganic iron and higher iron conversion and accumulation capacity. The aim of this study was to investigate the effect of S. cerevisiae enriched iron as a potential organic iron supplement on mice with iron deficiency anemia. 60 male Kunming mice (KM mice, with strong adaptability and high reproduction rate, it can be widely used in pharmacology, toxicology, microbiology and other research) were randomly divided into normal control group and iron deficiency diet model group to establish IDA model. After the model was established, IDA mice were randomly divided into 5 groups: normal control group, IDA group, organic iron group (ferrous glycinate), inorganic iron group (ferrous sulfate) and S. cerevisiae enriched iron group. Mice in the experimental group were given different kinds of iron by intragastric administration once a day for 4w. The results showed that S. cerevisiae enriched iron had an effective recovery function, and the body weight and hematological parameters of IDA mice returned to normal levels. The activities of superoxide dismutase, glutathione peroxidase and total antioxidant capacity in serum were increased. In addition, the strain no. F8, able to grow in an iron-rich environment, was more effective in alleviating IDA and improving organ indices with fewer side effects compared to ferrous glycinate and ferrous sulfate groups. This study suggests that the iron-rich strain no. F8 may play an important role in improving IDA mice and may be developed as a new iron supplement.

Role of biochar pyrolysis temperature on intracellular and extracellular biodegradation of biochar-adsorbed organic compounds

Immobilizing organic pollutants by adsorption of biochar in farmland soil is a cost-effective remediation method for contaminated soil. As the adsorption capacity of biochar is limited, biodegradation of biochar-adsorbed organic pollutants was a potential way to regenerate biochars and maintain the adsorption performance of biochars to lower the cost. It could be affected by the biochar pyrolysis temperature, but was not evaluated yet. In this study, biodegradation of adsorbed phenanthrene on a series of biochars with pyrolysis temperatures from 150 to 700 °C by Sphingobium yanoikuyae B1 was investigated using batch experiments of biodegradation kinetics at 30 °C, to explore the role of biochar pyrolysis temperature on biodegradation of biochar-adsorbed organic compounds. It was observed that 37.5-47.9% of adsorbed phenanthrene on moderate temperature-pyrolyzed biochars produced at 400 and 500 °C were biodegraded, less than that on high temperature-pyrolyzed biochars produced at ≥600 °C (48.8-60.8%) and low temperature-pyrolyzed biochars produced at ≤300 °C (63.4-92.5%). Phenanthrene adsorbed largely on the low temperature-pyrolyzed biochars by partition mechanism and thus is easily desorbed to water for a dominated intracellular biodegradation. On the high temperature-pyrolyzed biochars, phenanthrene is adsorbed largely by pore-filling mechanism and thus less desorbed to water for intracellular biodegradation. However, high temperature-pyrolyzed biochars can promote microbes to produce siderophore, H2O2 and thus release extracellular •OH for a dominated degradation of adsorbed phenanthrene by Fenton-like reaction. With the increase of biochar pyrolysis temperature, desorption and consequently the intracellular biodegradation of adsorbed phenanthrene on biochars decreased, while the secretion of siderophore and H2O2 by microbes on biochars increased to produce more extracellular •OH for degradation by Fenton-like reaction. The results could provide deep insights into the role of biochar pyrolysis temperature on biodegradation of biochar-adsorbed organic compounds, and optimize the selection of biochar with higher adsorption performance and easier regeneration for soil remediation.

Production of iron enriched Saccharomyces boulardii: impact of process variables

About half of the 1.62 billion cases of anemia are because of poor diet and iron deficiency. Currently, the use of iron-enriched yeasts can be used as the most effective and possible way to prevent and treat anemia due to the ability of biotransformation of mineral compounds into the organic form. In this research, for the first time, Saccharomyces (S.) boulardii was used for iron enrichment with the aim that the probiotic properties of yeast provide a potential iron supplement besides improving the bioavailability of iron. Also, due to its higher resistance than other Saccharomyces strains against stresses, it can protect iron against processing temperatures and stomach acidic-enzymatic conditions. So, the effect of three important variables, including concentration of iron, molasses and KH2PO4 on the growth and biotransformation of yeast was investigated by the Box-Behnken design (BBD). The best conditions occurred in 3 g/l KH2PO4, 20 g/l molasses and 12 mg/l FeSO4 with the highest biotransformation 27 mg Fe/g dry cell weight (DCW) and 6 g/l biomass weight. Such yeast can improve fermented products, provide potential supplement, and restore the lost iron of bread, which is a useful iron source, even for vegetarians-vegans and play an important role in manage with anemia. It is recommended that in future researches, attention should be paid to increasing the iron enrichment of yeast through permeabilizing the membrane and overcoming the structural barrier of the cell wall.

Effect of replacing inorganic iron with iron-rich microbial preparations on growth performance, serum parameters and iron metabolism of weaned piglets

This study aimed to investigate the effects of replacing of dietary inorganic iron with iron-rich Lactobacillus plantarum and iron-rich Candida utilis on the growth performance, serum parameters, immune function and iron metabolism of weaned piglets. Fifty-four 28-day-old healthy Duroc × Landrace × Yorkshire castrated male weanling piglets of similar body weight were randomly and equally divided into three groups. The piglets were kept in three pens per group, with six pigs in each pen. The dietary treatments were (1) a basal diet + ferrous sulfate preparation containing 120 mg/kg iron (CON); (2) a basal diet + iron-rich Candida utilis preparation containing 120 mg/kg iron (CUI); and (3) a basal diet + iron-rich Lactobacillus plantarum preparation containing 120 mg/kg iron (LPI). The entire feeding trial lasted for 28 days, after which blood, viscera, and intestinal mucosa were collected. The results showed no significant difference in growth parameters and organ indices of the heart, liver, spleen, lung, and kidney of weaned piglets when treated with CUI and LPI compared with the CON group (P > 0.05). However, CUI and LPI significantly reduced the serum contents of AST, ALP, and LDH (P < 0.05). Serum ALT content was significantly lower in the LPI treatment compared to the CON group (P < 0.05). Compared to CON, CUI significantly increased the contents of serum IgG and IL-4 (P < 0.05), and CUI significantly decreased the content of IL-2. LPI significantly increased the contents of serum IgA, IgG, IgM and IL-4 (P < 0.05), while LPI significant decreased the levels of IL-1β, IL-2, IL-6, IL-8, and TNF-α compared to CON (P < 0.05). CUI led to a significant increase in ceruloplasmin activity and TIBC (P < 0.05). LPI significantly increased the contents of serum Fe and ferritin, and increased the serum ceruloplasmin activity and TIBC compared to CON (P < 0.05). Furthermore, CUI resulted in a significant increase in the relative mRNA expression of FPN1 and DMT1 in the jejunal mucosa (P < 0.05). LPI significantly increased the relative mRNA expression of TF, FPN1, and DMT1 in the jejunal mucosa (P < 0.05). Based on these results, the replacement of dietary inorganic iron with an iron-rich microbial supplement could improve immune function, iron absorption and storage in piglets.

Iron-rich Candida utilis improves intestinal health in weanling piglets

AIM

This study aimed to investigate the effects of substituting inorganic iron in the diet of weanling piglets with iron-rich Candida utilis on gut morphology, immunity, barrier, and microbiota.

METHODS AND RESULTS

Seventy-two healthy 28-day-old Duroc × Landrace × Yorkshire desexed male weanling piglets were randomly assigned to 2 groups (n = 6), with 6 pens per group and 6 piglets in each pen. The control group was fed a basal diet containing ferrous sulfate (104 mg kg-1 iron), while the experimental group was fed a basal diet supplemented with iron-rich C. utilis (104 mg kg-1 iron). The results show that the growth performance of weanling piglets showed no significantly differences (P > 0.05). Iron-rich C. utilis significantly elevated villus height and decreased crypt depth in the duodenum and jejunum (P < 0.05). Additionally, there was a significant increase in SIgA content, a down-regulated of pro-inflammatory factors expression, and an up-regulated of anti-inflammatory factors expression in the jejunum and ileum of piglets fed iron-rich C. utilis (P < 0.05). The mRNA expression levels of ZO-1, Claudin-1, Occludin, and Mucin2 in the jejunum were significantly increased by iron-rich C. utilis, and were significantly increased ZO-1 and Claudin-1 in the ileum (P < 0.05). The colonic microbiota, however, was not significantly affected by iron-rich C. utilis (P > 0.05).

CONCLUSION

Iron-rich C. utilis improved intestinal morphology and structure, as well as intestinal immunity and intestinal barrier function.

Effect of High Efficiency Digestion and Utilization of Organic Iron Made by Saccharomyces cerevisiae on Antioxidation and Caecum Microflora in Weaned Piglets

Organic iron is expected to replace inorganic iron used in diets as an iron source. Organic iron possesses high absorption efficiency and low fecal iron excretion. This study aims to study the effect of organic iron produced by Saccharomyces cerevisiae (yeast iron) on digestion, utilization, antioxidation and caecum microflora in weaned piglets. In total, 20 piglets that had been weaned after 28 days were divided into 4 groups, each of which followed a different basal diet. The basal diet of each of these 4 groups contained, respectively, 104 mg/kg iron (ferrous sulfate, CON), 84 mg/kg iron (yeast iron, LSC), 104 mg/kg iron (yeast iron, MSC) or 124 mg/kg iron (yeast iron, HSC). This experiment lasted 35 d. The apparent digestibility of iron in LSC, MSC and HMS was higher than that in CON (p < 0.01) and the fecal iron content in LSC, MSC and HMS was lower than that in CON (p < 0.01). Serum iron contents in LSC, MSC and HMS were higher than that in CON (p < 0.01). The iron contents of the heart, lungs, liver, kidney and left gluteus muscle in the MSC and HMS groups were higher than that in CON and LSC (p < 0.05). Serum catalase, glutathione peroxidase, superoxide dismutase activity, superoxide anion, glutathione, hydroxyl free radical scavenging rate, total antioxidant capacity, and liver superoxide anion clearance rate and peroxidase in MSC and HMS were higher than that in CON and LSC (p < 0.05). The contents of nitric oxide and peroxide of the weaned piglets in MSC and HMS were lower than that in CON and LSC (p < 0.05). The abundance of Firmicutes, Blautia and Peptococcus in LSC, HSC and MSC was higher than that in CON (p < 0.01). The abundance of Lactobacillus in CON and LSC was higher than that in MSC and HSC (p < 0.01). The abundance of Acinetobacter, Streptococcus and Prevotella in LSC, MSC and HSC was lower than that in CON (p < 0.01). The results suggested that a diet containing 84 mg/kg iron of yeast iron has the same effect as a diet containing 104 mg/kg iron of ferric sulfate, and that a diet containing 104 or 124 mg/kg iron of yeast iron is superior to a diet containing 104 mg/kg iron of ferric sulfate.

Emerging Target-Directed Approaches for the Treatment and Diagnosis of Microbial Infections

With the rising levels of drug resistance, developing efficient antimicrobial therapies has become a priority. A promising strategy is the conjugation of antibiotics with relevant moieties that can potentiate their activity by target-directing. The conjugation of siderophores with antibiotics allows them to act as Trojan horses by hijacking the microorganisms' highly developed iron transport systems and using them to carry the antibiotic into the cell. Through the analysis of relevant examples of the past decade, this Perspective aims to reveal the potential of siderophore-antibiotic Trojan horses for the treatment of infections and the role of siderophores in diagnostic techniques. Other conjugated molecules will be the subject of discussion, namely those involving vitamin B12, carbohydrates, and amino acids, as well as conjugated compounds targeting protein degradation and β-lactamase activated prodrugs.

Microbial degradation of nondesorbable organic compounds on biochars by extracellular reactive oxygen species

Knowledge of microbial degradation of biochar-adsorbed organic pollutants is essential for recovering adsorption performance of biochars and reducing secondary pollution in soil remediation. In previous study, desorption of organic compounds from biochars was perceived as a prerequisite for the microbial degradation. However, microbial degradation of the nondesorbable organic compounds on biochars has not been studied. Therefore, degradation of nondesorbable naphthalene (NAPH), phenanthrene (PHEN) and pyrene (PYR) on a wood chip-derived biochar (WBC700) by Sphingobium yanoikuyae B1 was investigated. Significant microbial degradations of nondesorbable organic compounds were observed and followed the order of NAPH < PHEN < PYR. It was newly observed in this study that the microbial degradation of nondesorbable organic compounds on WBC700 was mainly attributed to the •OH in extracellular fluid of Sphingobium yanoikuyae B1. The extracellular •OH was produced through a Fenton-like reaction involved siderophore, H₂O₂ and iron ions, which could be significantly enhanced by WBC700. Microbial degradation was higher for larger organic compound (e.g., PYR), because larger molecules were adsorbed in relatively larger micropores of WBC700 and thus could be accessible to more extracellular •OH for degradation. The obtained results could provide a new insight into the microbial degradation of biochar-adsorbed organic pollutants in soil remediation.

The Purified Siderophore from Streptomyces tricolor HM10 Accelerates Recovery from Iron-Deficiency-Induced Anemia in Rats

Iron-deficiency-induced anemia is associated with poor neurological development, including decreased learning ability, altered motor functions, and numerous pathologies. Siderophores are iron chelators with low molecular weight secreted by microorganisms. The proposed catechol-type pathway was identified based on whole-genome sequences and bioinformatics tools. The intended pathway consists of five genes involved in the biosynthesis process. Therefore, the isolated catechol-type siderophore (Sid) from Streptomyces tricolor HM10 was evaluated through an anemia-induced rat model to study its potential to accelerate recovery from anemia. Rats were subjected to an iron-deficient diet (IDD) for 42 days. Anemic rats (ARs) were then divided into six groups, and normal rats (NRs) fed a standard diet (SD) were used as a positive control group. For the recovery experiment, ARs were treated as a group I; fed an IDD (AR), group II; fed an SD (AR + SD), group III, and IV, fed an SD with an intraperitoneal injection of 1 μg Sid Kg^-1 (AR + SD + Sid1) and 5 μg Sid Kg^-1 (AR + SD + Sid5) twice per week. Group V and VI were fed an iron-enriched diet (IED) with an intraperitoneal injection of 1 μg Sid Kg^-1 (AR + IED + Sid1) and 5 μg Sid Kg^-1 (AR + IED + Sid5) twice per week, respectively. Weight gain, food intake, food efficiency ratio, organ weight, liver iron concentration (LIC) and plasma (PIC), and hematological parameters were investigated. The results showed that ~50-60 mg Sid L^-1 medium could be producible, providing ~25-30 mg L^-1 purified Sid under optimal conditions. Remarkably, the AR group fed an SD with 5 μg Sid Kg^-1 showed the highest weight gain. The highest feed efficiency was observed in the AR + SD + Sid5 group, which did not significantly differ from the SD group. Liver, kidneys, and spleen weight indicated that diet and Sid concentration were related to weight recovery in a dose-dependent manner. Liver iron concentration (LIC) in the AR + IED + Sid1 and AR + IED + Sid5 groups was considerably higher than in the AR + SD + Sid1 AR + SD + Sid5 groups or the AR + SD group compared to the AR group. All hematological parameters in the treated groups were significantly closely attenuated to SD groups after 28 days, confirming the efficiency of the anemia recovery treatments. Significant increases were obtained in the AR + SD + Sid5 and AR + IED + Sid5 groups on day 14 and day 28 compared to the values for the AR + SD + Sid1 and AR + IED + Sid1 groups. The transferrin saturation % (TSAT) and ferritin concentration (FC) were significantly increased with time progression in the treated groups associatively with PIC. In comparison, the highest significant increases were noticed in ARs fed IEDs with 5 μg Kg^-1 Sid on days 14 and 28. In conclusion, this study indicated that Sid derived from S. tricolor HM10 could be a practical and feasible iron-nutritive fortifier when treating iron-deficiency-induced anemia (IDA). Further investigation focusing on its mechanism and kinetics is needed.

Intestinal microbiomics and liver metabolomics insights into the preventive effects of chromium (III)-enriched yeast on hyperlipidemia and hyperglycemia induced by high-fat and high-fructose diet

In recent years, organic chromium (III) supplements have received increasing attentions for their low toxicity, high bioavailability and wide range of health-promoting benefits. This study aimed to investigate the preventive effects of chromium (III)-enriched yeast (YCr) on high-fat and high-fructose diet (HFHFD)-induced hyperlipidemia and hyperglycemia in mice, and further clarify its mechanism of action from the perspective of intestinal microbiomics and liver metabolomics. The results indicated that oral administration of YCr remarkably inhibited the aberrant elevations of body weight, blood glucose and lipid levels, hepatic cholesterol (TC) and triglyceride (TG) levels caused by HFHFD. Liver histological examination showed that oral YCr intervention inhibited HFHFD induced liver lipid accumulation. Besides, 16S rDNA amplicon sequencing showed that YCr intervention was beneficial to ameliorating intestinal microbiota dysbiosis by altering the proportion of some intestinal microbial phylotypes. Correlation-based network analysis indicated that the key intestinal microbial phylotypes intervened by YCr were closely related to some biochemical parameters associated with glucose and lipid metabolism. Liver metabolomics analysis revealed that dietary YCr intervention significantly regulated the levels of some biomarkers involved in purine metabolism, glycerophospholipid metabolism, citrate cycle, pyrimidine metabolism, glycerophospholipid metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, and so on. Moreover, dietary YCr intervention regulated the mRNA levels of key genes associated with glucose, cholesterol, fatty acids and bile acids metabolism in liver. These findings suggest that dietary YCr intervention has beneficial effects on glucose and lipid metabolism by regulating intestinal microbiota and liver metabolic pathway, and thus can be served as a functional component to prevent hyperlipidemia and hyperglycemia.

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Chromium-enriched yeast enhances glucose tolerance and liver glycogen synthesis.

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Chromium-enriched yeast ameliorates the disturbance of intestinal microbiota.

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Explore the hepatoprotective effect of chromium-enriched yeast based on metabolomics.

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Chromium-enriched yeast alleviates lipid metabolism through “gut-liver” axis.

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Chromium-enriched yeast intervention affects hepatic gene transcription levels.

Reducing Phenanthrene Contamination in Trifolium repens L. With Root-Associated Phenanthrene-Degrading Bacterium Diaphorobacter sp. Phe15

Some root-associated bacteria could degrade polycyclic aromatic hydrocarbons (PAHs) in contaminated soil; however, their dynamic distribution and performance on root surface and in inner plant tissues are still unclear. In this study, greenhouse container experiments were conducted by inoculating the phenanthrene-degrading bacterium Diaphorobacter sp. Phe15, which was isolated from root surfaces of healthy plants contaminated with PAHs, with the white clover (Trifolium repens L.) via root irrigation or seed soaking. The dynamic colonization, distribution, and performance of Phe15 in white clover were investigated. Strain Phe15 could efficiently degrade phenanthrene in shaking flasks and produce IAA and siderophore. After cultivation for 30, 40, and 50 days, it could colonize the root surface of white clover by forming aggregates and enter its inner tissues via root irrigation or seed soaking. The number of strain Phe15 colonized on the white clover root surfaces was the highest, reaching 6.03 Log CFU⋅g^–1 FW, followed by that in the roots and the least in the shoots. Colonization of Phe15 significantly reduced the contents of phenanthrene in white clover; the contents of phenanthrene in Phe15-inoculated plants roots and shoots were reduced by 29.92–43.16 and 41.36–51.29%, respectively, compared with the Phe15-free treatment. The Phe15 colonization also significantly enhanced the phenanthrene removal from rhizosphere soil. The colonization and performance of strain Phe15 in white clove inoculated via root inoculation were better than seed soaking. This study provides the technical support and the resource of strains for reducing the plant PAH pollution in PAH-contaminated areas.

Sterol Composition Modulates the Response of Saccharomyces cerevisiae to Iron Deficiency

Iron is a vital micronutrient that functions as an essential cofactor in multiple biological processes, including oxygen transport, cellular respiration, and metabolic pathways, such as sterol biosynthesis. However, its low bioavailability at physiological pH frequently leads to nutritional iron deficiency. The yeast Saccharomyces cerevisiae is extensively used to study iron and lipid metabolisms, as well as in multiple biotechnological applications. Despite iron being indispensable for yeast ergosterol biosynthesis and growth, little is known about their interconnections. Here, we used lipid composition analyses to determine that changes in the pattern of sterols impair the response to iron deprivation of yeast cells. Yeast mutants defective in ergosterol biosynthesis display defects in the transcriptional activation of the iron-acquisition machinery and growth defects in iron-depleted conditions. The transcriptional activation function of the iron-sensing Aft1 factor is interrupted due to its mislocalization to the vacuole. These data uncover novel links between iron and sterol metabolisms that need to be considered when producing yeast-derived foods or when treating fungal infections with drugs that target the ergosterol biosynthesis pathway.