Organic Acid Treatments Research Articles

Dynamics of Fe, Mn, and Al Liberated from Contaminated Soil by Low-Molecular-Weight Organic Acids and Their Effects on the Release of Soil-Borne Trace Elements

A 15-day batch experiment was conducted to investigate the behaviours of Fe, Mn, and Al oxides upon attack by three common low-molecular-weight organic acids, and their effects on liberation of trace elements from a multi-contaminated soil. While the capacity of malic acid to mobilize soil-borne Fe, Mn, and Al was weaker compared to citric and oxalic acids, a similar trend was observed, showing that the concentration of dissolved Fe, Mn, and Al increased with increasing duration of the experiment. Marked increase in metal concentrations only took place after 5 or 7 days of the experiment. For the same organic acid treatment, Fe, Mn, and Al all showed a very similar temporal variation pattern. The concentration of dissolved Fe, Mn, and Al was markedly controlled by the total Fe, Mn, and Al contained in the soil, respectively. It appears that manganese oxides were more reactive to the organic acids, as compared to their Fe and Al counterparts. However, when multiple organic acids were present, the soil-borne Fe, Mn, and Al were mobilized rapidly within the first 5 or 7 days of the experiment and then tended to decrease. The formation of insoluble Fe, Mn, and Al organic complexes tended to be enhanced due to co-existence of multiple organic acids, resulting in the re-immobilization of the dissolved Fe, Mn, and Al. The organic acid-driven dissolution of Fe, Mn, or Al had a major control on the mobilization of As, Cr, Zn, Ni, Cu, and Cd that were bound to these oxides with a correlation coefficient being frequently greater than 0.9 for As, Cr, Zn, and Ni.

Development of Decellularized Cornea by Organic Acid Treatment for Corneal Regeneration.

This study successfully developed decellularized corneal scaffolds that were prepared by organic acid, which safely exist in animal tissues and plants. The results showed the highly efficient removal of cell debris from porcine corneas, and excellent preservation of optical properties, extracellular matrix (ECM) architecture, and biomolecules. In addition, decellularized corneal scaffolds revealed excellent biocompatibility and recellularization potential in vitro. In an animal model, the transplanted corneas were completely epithelialized, clear, showed no signs of immune response, and effectively supported stromal keratocytes growth. Hence, this could be a promising scaffold material for corneal tissue engineering applications.

Green process development for apple-peel pectin production by organic acid extraction

To extract pectin in food industry, HCl is generally used as the major extracting solvent for releasing the pectin from the plant tissues, however it has an environmental issue to use. In this study, food-grade tartaric-, malic, and citric acids were used to produce apple peel pectin as an eco-friendly protocol instead of HCl. Finely-ground lyophilized apple peel was applied as the raw material, and the pectin was extracted by organic acids at 85 °C. The pectin extracted with citric acid displayed greater molecular weight and apparent viscosity compared to other organic acid treatments. Analysis of degree of methyl esterification revealed that the pectins extracted with organic acids were highly methoxylated. From these results, it was suggested that organic acids could be utilized to extract apple peel pectin effectively as a green process. Especially, the extraction process with citric acid as the solvent showed great potential to produce high-viscosity apple peel pectin.

Exogenous citrate and malate alleviate cadmium stress in Oryza sativa L.: Probing role of cadmium localization and iron nutrition

Organic acids play an important role in metal uptake and trafficking in plants. Therefore, the role of exogenous citrate and malate on Cd tolerance was studied in the seedlings of Oryza sativa L. cv MTU 7029. Seedlings were exposed to Cd plus organic acids in hydroponics and monitored changes in Cd accumulation, expression of metal transporters, chlorophyll fluorescence, and antioxidants. It found that organic acid supplements decrease Cd accumulation in leaf because of up-regulation of tonoplast localized heavy metal ATPase (OsHMA3) which allows vacuolar sequestration of Cd in the root. Malic acid helped Cd exclusion in the root too. A shift in Cd speciation from sulphhydryl to the carboxylic group also noticed in the roots of plants exposed to organic acids. Treatment of organic acids was effective to prevent Cd inducible Fe deficiency via up-regulation of the iron-regulated transporter (OsIRT1), increase in ferric chelate reductase activity, and formation of Cd stabilized Fe3+ - organic acid complex respectively. Also, exposure to organic acids increased the accumulation of antioxidants such as anthocyanin and glutathione (GSH) under Cd stress. Above changes assisted in upholding of photosynthetic electron transport and biomass productivity during the course of Cd treatment with organic acid supplements.

The role of organic acids on the uptake and relationship of phosphorus and zinc in corn (Zea mays L.) by application of 32P and 65Zn radioisotopes

ABSTRACTTo investigate the effect of oxalic and citric acids on the uptake and relationship of phosphorus and zinc in corn (Zea mays L.), some greenhouse experiments were performed by individual and combined application of monopotassium phosphate [KH232PO4] and zinc sulfate [65ZnSO4.7H2O] fertilizers in microcosm. For this purpose after planting corn seeds, solutions of phosphorus (32P) and zinc (65Zn) (14 and 2 M) and organic acids treatments (1 and 10 mM) were injected in microcosms at suitable times. Then, plants were harvested, digested, extracted, and activity of 32P and 65Zn was measured in samples. Results revealed that the highest uptake of 32P in shoots was 18.8% and observed at 10 mM concentration of oxalic acid. But no effect on 65Zn uptake was seen and the highest uptake was observed in control (1.27%). The highest uptake of 32P and 65Zn in plant shoots and roots was observed at 10 mM concentration of oxalic and citric acids, respectively.

Anti-bacterial and anti-biofilm activity of commercial organic acid products against Salmonella enterica isolates recovered from an egg farm environment

ABSTRACTThis study evaluated the antibacterial activity of commercially available organic acid water additives against Salmonella enterica isolates and examined the susceptibility of Salmonella Typhimurium biofilms to these products. Three commercial organic acid products (A, B, and C) were evaluated for minimum inhibitory and bactericidal concentrations against isolates of S. enterica serovars. Three- and five-day-old S. Typhimurium biofilms were formed at 22 ± 2°C using an MBEC™ assay system and exposed for 30 min or 90 min at 0.2% and 0.4% concentrations. No significant difference among serovars for inhibitory and bactericidal concentrations was detected. Two products (A and C) significantly reduced viable cells from biofilms of both ages in a dose- and time-dependent manner. Increased biofilm age did not enhance resistance towards organic acid treatments. None of the products completely eliminated biofilm cells at any concentration or exposure time. Product composition, exposure time, and concentration of organic acid products were important factors in reducing viable biofilm cells. This study has expanded our understanding about the susceptibility of Salmonella biofilms to commercial organic acid products. These findings have implications in the usage, development, and optimization of organic acid products.

Investigating the dynamics of excitons in monolayer WSe2 before and after organic super acid treatment.

Due to the large photoluminescence quantum yield, high mobility and good stability, organic super acid treated two-dimensional WSe2 has drawn much attention. However, reports about the influence of organic super acid treatment on the dynamic processes of excitons of monolayer WSe2 are still rare. In this work, through the broadband transient absorption spectra obtained using a femtosecond pump-probe system, we determine the dynamics of A' and C excitons in monolayer and bulk WSe2 at room temperature. Besides this, we also observe the relaxation process of the holes between the two spin split states in the valence band maximum in organic super acid treated monolayer WSe2. We find that the organic super acid treatment on monolayer WSe2 does not change the peak positions of the exciton states, while those bleaching peaks' intensities increase significantly due to the enhancement of oscillator strength for exciton states, corresponding to stronger steady-state photoluminescence. This could be attributed to the strain release induced by the defect repairing effect during the organic super acid treatment process.

Comparative Studies of the Effect of Inorganic and Organic Acid Treatment on Chitosan Property from Shrimp Shells

Comparative Studies of the Effect of Inorganic and Organic Acid Treatment on Chitosan Property from Shrimp Shells

The Effects of Different Organic Acid Treatments on Some Microflora and Pathogen Listeria monocytogenes of White Brine Cheese

The Effects of Different Organic Acid Treatments on Some Microflora and Pathogen Listeria monocytogenes of White Brine Cheese

Effects of Different Levels of Organic and Inorganic Acids Treatment on Quality and Ruminal Dry Matter and Nutrients Degradability of Iranian Clover Silage

Effects of Different Levels of Organic and Inorganic Acids Treatment on Quality and Ruminal Dry Matter and Nutrients Degradability of Iranian Clover Silage

Growth performance, nutrient digestibility, fecal microbiota and fecal noxious gas emission in weaning pigs fed high and low density diet with and without protected organic acid blends

This study was conducted to evaluate the effects of dietary supplementation of protected organic acid blends including medium chain fatty acids and different nutrient density diets on growth performance, nutrient digestibility, fecal microbiota and fecal noxious gas emission in weaning pigs. A total of 90 crossbred [(Landrace × Yorkshire) × Duroc] weaning pigs with an initial body weight (BW) of 6.54 ± 0.78 kg were used in a six-week trial. Pigs were randomly allocated into one of six treatment groups in a 2 × 3 factorial arrangement with two nutrient density diets; high density (HD) vs low density (LD) supplemented with or without two levels (0.1 and 0.2%) of protected organic acids (OA) according to their sex and BW (3 replicate pens per treatment with 2 gilts and 3 barrows per pen). The inclusion of OA (0.1%, 0.2%) improved (P < 0.05) the average daily gain (ADG) during week 6. Likewise, during the overall experimental period, the ADG was higher (P < 0.05) in pigs fed HD diet than LD diet as well as in OA supplemented diet, but average daily feed intake (ADFI) was significantly improved (P < 0.05) only in diet supplemented with OA than non-supplemented diet. The gain: feed (G:F) ratio was higher (P < 0.05) in pigs fed HD than LD diet during week 3 and week 6 and overall experimental periods. The supplementation of OA (0.2%) led to a higher (P < 0.05) apparent total tract digestibility (ATTD) of energy during week 3 and week 6 compared with non-supplemented diet. In week 3, dry matter (DM) digestibility was higher in pigs fed diet supplemented with 0.2% OA but in week 6, DM digestibility was higher in both 0.1% and 0.2% OA treatments compared with control. The ATTD of energy was higher (P < 0.05) in pigs fed HD than LD diet during week 6. The supplementation of OA (0.2%) in the diet reduced fecal E.coli during week 3 and increased Lactobacillus counts during week 6. However, the fecal noxious gas emissions were not affected either by OA or diets. In conclusion, protected OA and different density diets improved growth performance, nutrient digestibility but no interactive effects with different density diets and OA were observed.

Environmental Impacts of some Organic Extracts on Sugar Beet Yield under Saline-Sodic Soil Conditions

The objective of this study is to evaluate the effects of different organic extracts (natural or synthetic) as stimulator substances on sugar beet yield and soil properties. Two field experiments were carried out during two successive seasons (2016 and 2017) in a private farm at Port-Said site, Egypt. Tomato and banana peels were used as natural organic extracts while citric acid and malic acid were used as synthetic organic extracts. Natural and synthetic extracts were applied to soil. The results showed that either synthetic or natural organic extract individual or combined led to significant increases in root and sugar yields/fed. The highest values of sugar yields were obtained using synthetic organic extracts application followed by natural organic extracts. The results revealed also that, natural peel extracts showed a significant increase in the sucrose% comparing with the synthetic organic acids. Sucrose% reached 22% for both peels extracts while it reached 17% for both organic acids treatments. The application of synthetic or natural organic extract improved nutritional values of sugar beet plant. There was excellent potential to obtain a purity% of sugar using natural peel extracts. Applying the combination of banana extract and citric acid showed the maximum reduction in soil salinity (18.5%), whereas applying Tomato extract individually showed the minimum reduction of soil salinity (7.9%) compared to control. The Soil pH decreased insignificantly in case of treatments relative to the control. Moreover, applying these extracts led to a decrease in both sodium and potassium cations content of the soil under this study. Adding organic extract (natural or synthetic) led to a pronounced decrease in both SAR and ESP values as compared with the control. So, these extracts can be used for reducing soil salinity and improve the long term productivity of this soil for sustainable agriculture.

Effects of Selected Root Exudate Components on Nitrogen Removal and Development of Denitrifying Bacteria in Constructed Wetlands

Root exudates, particularly low molecular weight carbon (LMWC) substrates, are major drivers of bacterial diversity and activity in the rhizosphere environment. However, it is not well understood how specific LMWC compounds—such as organic acids, soluble sugars, and amino acids—influence the community structures of denitrifying bacteria or if there are specific functions of LMWC substrates that preferentially respond to nitrogen (N) removal in constructed wetlands (CWs). To address these knowledge gaps, we added mixtures of artificial exudates to CW microcosms containing N pollutant. N removal efficiency was observed over a 48-h experimental period, and at the end of the experiment, DNA was extracted from microbial samples for assessment of the bacterial community. The removal efficiencies of TN for the exudates treatments were higher than for control groups by 47.1–58.67%. Organic acid and soluble sugar treatments increased N removal, while amino acids were negative to N removal. The microbial community was changed when artificial exudates were added, but there were no significant relationships between LMWC compounds and bacterial community composition. These results indicate that although the responses of community structures of denitrifying bacteria to LMWC additions are still uncertain, there is evidence for N removal in response to exudate additions across LMWC types.

H9N2-specific IgG and CD4+ CD25+ T cells in broilers fed a diet supplemented with organic acids

Organic acids have long been known for their beneficial effects on growth performance in domestic animals. However, their impact on immune responses against viral antigens in chickens is unclear. The present study aimed to investigate immunological parameters in broilers immunized with a H9N2 vaccine and/or fed a diet containing organic acids (citric, formic, and lactic acids). We allotted 1-day-old broilers into 4 groups: control (C), fed a diet supplemented with organic acids (O), administered a H9N2 vaccine (V), and fed a diet supplemented with organic acids and administered a H9N2 vaccine (OV). Blood and spleen samples were taken at 2, 7 and 14 d post vaccination (DPV). At 14 DPV, total and H9N2-specific IgG levels were significantly lower in the OV group than in the V group. However, it was intriguing to observe that at 2 DPV, the percentage of CD4+ CD25+ T cells was significantly higher in the OV group than in the other groups, indicating the potential induction of regulatory T cells by organic acids. In contrast, at 2 DPV, the percentage of CD4+ CD28+ T cells were significantly lower in the OV group than in the other groups, suggesting that CD28 molecules are down-regulated by the treatment. The expression of CD28 on CD4+ T cells, up-regulated by the stimulation with phorbol 12-myristate 13-acetate (PMA) and ionomycin (Iono), was inhibited upon organic acid treatment in OV group. In addition, the proliferation of lymphocytes, stimulated with formalin-inactivated H9N2, was significantly higher in the V group than in the OV group. Alpha 1-acid glycoprotein (AGP) production was significantly lower in the OV group than in the V group, suggesting that the organic acids inhibited the inflammation caused by the vaccination. Overall, induction of regulatory CD4+ CD25+ T cells, coinciding with the decrease of H9N2-specific antibodies, was observed in broilers fed organic acids.

Effect of Saline Organic Acid Solutions Applied During Wheat Tempering on Flour Functionality

Previously, we showed that tempering with saline organic acid solutions can reduce the aerobic plate count of wheat by as much as 4.3 log CFU/g. The purpose of this study was to evaluate the impact of these tempering solutions on the functional properties of resulting whole grain (WGF) and straight‐grade (SGF) flours. Wheat was tempered to 15.5% moisture by tempering with sterile distilled water (control) or solutions containing NaCl (26% [w/v]) together with organic acid (acetic or lactic 2.5 and 5.0% [v/v]). After milling, fractions were collected and recombined as needed to obtain WGF or SGF. The acid content in WGF was higher than in SGF, indicating limited penetration of the organic acids into the endosperm of the grain. In WGF, the saline organic acid treatments caused a decrease in paste viscosity and bread crumb cell sizes in breads. In SGF, the saline organic acid treatments caused significant changes in paste viscosity and some Mixograph parameters; however, principal components analysis indicated that the treatments did not substantially affect SGF functionality. Thus, WGF was altered by the saline organic acid solutions, whereas SGF functionality was minimally affected by tempering treatments, perhaps because of acids only partially penetrating into the endosperm.

Stress responses of honey bees to organic acid and essential oil treatments against varroa mites

Natural medicines such as formic acid, oxalic acid, thymol and menthol have recently been used as alternative treatments against the honey bee parasitic mite varroa. The aim of this study was to observe and examine their impact on Heat Shock Proteins (HSP 70) in the brain tissues of bees. For this purpose, seven different treatment groups were created using various concentrations and administrations of formic and oxalic acid and thymol-menthol mixtures, including positive (untreated) and negative controls. The results showed that in the groups exposed to the varroa treatments, HSP 70 results were lower than those of the non-treated groups. HSP 70 results were lowest in the thymol-menthol mixture exposed group among the treated groups. We conclude that it would be more beneficial to prefer natural medicines against varroa, which lead to lower HSP 70 results which are the molecular determinants of stress.

Bi-functional anodic TiO2 oxide: Nanotubes for wettability control and barrier oxide for uniform coloring

A uniformly colored TiO2, on which the surface is functionalized with nanotubes to control wettability, was prepared by a two-step anodization; the first anodization was carried out to prepare nanotubes for a super-hydrophilic or -hydrophobic surface and the second anodization was performed to fabricate a thin film barrier oxide to ensure uniform coloring. The effect of the nanotubes on barrier oxide coloring was examined by spectrophotometry and UV-vis-IR spectroscopy. We found four different regimes governing the color changes in terms of anodization voltage, indicating that the color of the duplex TiO2 was primarily determined by the thickness of the barrier oxide layer formed during the second anodization step. The surface wettability, as confirmed by the water contact angle, revealed that the single barrier TiO2 yielded 74.6°±2.1, whereas the nanotubes on the barrier oxide imparted super-hydrophilic properties as a result of increasing surface roughness as well as imparting a higher hydrophobicity after organic acid treatment.

Rheological properties of rice flour treated with mild solutions of citric acid.

Effects of milling methods and organic acids treatments on rheological properties of rice flour were investigated. The average particle-size of wet-milled rice flour was lower and showed lower pasting temperature, peak viscosity, and storage modulus values than those of dry-milled rice flour. Wet-milled rice flour treated with citric acid showed significantly low viscosity and viscoelastic properties, as the concentration of citric acid increased, whereas wet-milled rice flour treated with acetic acid was not significantly affected by the acetic acid concentration. Rheological property of baekseolgi (Korean rice cake) made with wet-milled citric-acid-treated rice flour showed a similar trend in viscoelasticity, wherein citric acid treatment lowered the hardness of the rice. However, cohesiveness increased with increasing citric acid concentration. Overall, milling method affected the particle size, which influenced the viscosity and heat stability, whereas citric acid treatment affected the rheological properties of rice flour. These results are expected to contribute to the development of an appropriate method for rice flour application.

Physicochemical characteristics and in vitro digestibility of potato and cassava starches under organic acid and heat-moisture treatments

A combination of acid (citric acid or lactic acid) and heat-moisture treatment was used to modify cassava and potato starches in this study. Changes in physicochemical properties and in vitro digestibility of the treated starches were investigated. The cassava starch contained 17.0% amylose and possessed A-type crystallinity, whereas the potato starch had 27.4% amylose and possessed B-type crystallinity. After acid and heat-moisture treatment, the crystalline structure of the cassava starch remained unchanged (A type), while the crystalline structure of the potato starch changed from B type to the C (B+A) type. The acid and heat-moisture treatment increased gelatinization temperature, peak and final viscosities of cassava starch but reduced peak and breakdown viscosities of the potato starch. After acid and heat-moisture treatment, rapid digestible starch contents of the treated cassava and potato starches were significantly reduced. However, resistant starch (RS) contents of the treated starches significantly increased as compared to the native starches. Citric acid was found to have high impact on formation of RS in starches. The RS contents of cassava and potato starches obtained under the citric acid and heat-moisture treatment were 40.2% and 39.0%, respectively, two times higher than those of the native starches.

Influence of lead in the sorption of arsenate by municipal solid waste composts: metal(loid) retention, desorption and phytotoxicity

The ability of two municipal solid waste composts (MSW-C) to sorb As(V) in the presence of Pb(II) and in acidic conditions was investigated. Sorption isotherms and kinetics showed that both MSW-C were able to sorb As(V) in a similar way (∼0.24mmolg−1 MSW-C), but only when Pb(II) was present (0.45mmolL−1). The concomitant sorption of Pb(II) by both MSW-C (∼0.40mmolg−1) suggested that the metal cation was likely acting as bridging element between the negatively charged functional groups of composts and As(V). SEM-EDX analysis of the MSW-C+Pb(II)+As(V) systems supported the association between Pb(II) and As(V), while sequential extraction procedures and organic acids treatment showed that As(V) was strongly retained by MSW-C+Pb(II) and suggested the presence of different interaction types between As(V) and Pb(II). Plant growth experiments highlighted the key role of Pb(II) in the reduction of As(V)-phytotoxicity for triticale plants (×Triticosecale Wittm.) in the presence of MSW-C.