Effect of pH on Soil Chemical Properties and Maize Performance in Abakaliki, Nigeria

Background: Low soil productivity in Nigeria and Africa sub sahara is considered as one of the major causes of food insecurity and under nutrition. This area is considered among the most regions affected by acidity on soil nutrients optimization. Despite of its severity, there is limited knowledge about limiting effect of pH on nutrients availability and maize yield in the state. Evolving a technology that does not depend on traditional system of amendment for pH assessment for increased soil productivity must first of all go through a good knowledge of the nature and distribution of soil studied. The present study aimed to evaluate three pH (4, 7 and 9) values on soil chemical properties in the state and assess maize performance under these conditions in order to control and manage pH related problems. Methods: In the field-laboratory investigation during 2018-2019 at different localities of Ebonyi State were surveyed. Three sampling localities were selected based on geographical situation, climate and local condition. In the laboratory, the soil samples of natural stock collected were processed for mean pH values and confirmed with pH meter using standard laboratory method. Maize was used as test crop to assess effect of pH on its performance. Result: Our investigations in Ebonyi State have allowed us to inventory three pH values. Among the inventoried pH values, some are regarded adverse for soil productivity. The implication of soil pH on nutrients availability and maize performance was discussed. The current work will be a complementary contribution of detailed study of effect of pH on soil productivity.

The Effect of Activated Carbon Using on Aroma and pH Values in Yogurt Fermentation

Yogurt is a known food item all over the world. Consuming yogurt can be quite difficult for people with lactose intolerance at times. In addition to its active carbon adsorbent feature, it is a lactose chelate. It is aimed to use yoghurt prepared by using activated carbon for nutritional purposes. For this purpose, aroma and pH changes in yogurt made with activated carbon compared to classical yogurt production were studied. It was determined that the active carbon usage method used in the study did not cause any aroma change in yoghurt, however, it increased the pH. This result makes us think that lactose cannot be used by yogurt microorganisms and that yogurt with activated carbon may be an alternative for lactose intolerant people who want to consume yogurt.

Defluoridation performance comparison of aluminum hydroxides with different crystalline phases

Aluminum hydroxide is an eye catching and extensively researched adsorbent for fluoride removal and its defluoridation performance is closely related to the preparation method and crystalline phase. In this research, the defluoridation performances of aluminum hydroxides with different crystalline phases are compared and evaluated in terms of fluoride removal capacity, sensitivity to pH values and residual Al contents after defluoridation. It is found that the defluoridation performance of different aluminum hydroxides follows the order of boehmite > bayerite > gibbsite. The fluoride adsorption on aluminum hydroxides follows pseudo-second-order kinetic model and Langmuir isotherm model, and the maximum defluoridation capacities of boehmite, bayerite and gibbsite are 42.08, 2.97 and 2.74 mg m−2, respectively. The pH values and FTIR analyses reveal that the ligand exchange between fluoride and surface hydroxyl groups is the fluoride removal mechanism. Different aluminum hydroxides have different surface hydroxyl group densities, which results in the different defluoridation capacities. This work provides a new idea to prepare aluminum hydroxide with outstanding defluoridation performance.

Preparation of tambacu protein concentrates using different methodologies

The aim of this study was to develop methodologies to obtain fish protein concentrates from tambacu filleting residues, characterize their physical-chemical composition and evaluate their sensory profile. Concentrates were prepared by one of three methodologies: cooking of the raw material and subsequent drying (FPC1); cooking, drying, lipid removal with ethanol at 70 °C and final drying (FPC2); and three washing steps of the raw material with ethanol at 70 °C and drying (FPC3). FPC2 had a lower final yield (15.5%) and chroma a* (1.77) and chroma b* values (14.12) but higher moisture (5.22%) and protein content (80.39%) and luminosity (74.97), in addition to having the weakest fish taste compared to FPC1 and FPC3. FPC1 had the strongest odour, darkest colour, and strongest fish taste compared to FPC2 and FPC3. Ash, pH values, and water activity were not different between the concentrates. It is concluded that the methodology where lipid removal steps are carried out after cooking and drying (FPC2) is more effective for the removal of lipids and deodorization of tambacu protein concentrate.

Synthesis and Properties of Nitrogen-Doped Carbon Quantum Dots Using Lactic Acid as Carbon Source

Nitrogen-doped carbon quantum dots (N-CQDs) were synthesized in a one-step hydrothermal technique utilizing L-lactic acid as that of the source of carbon and ethylenediamine as that of the source of nitrogen, and were characterized using dynamic light scattering, X-ray photoelectron spectroscopy ultraviolet-visible spectrum, Fourier-transformed infrared spectrum, high-resolution transmission electron microscopy, and fluorescence spectrum. The generated N-CQDs have a spherical structure and overall diameters ranging from 1–4 nm, and their surface comprises specific functional groups such as amino, carboxyl, and hydroxyl, resulting in greater water solubility and fluorescence. The quantum yield of N-CQDs (being 46%) is significantly higher than that of the CQDs synthesized from other biomass in literatures. Its fluorescence intensity is dependent on the excitation wavelength, and N-CQDs release blue light at 365 nm under ultraviolet light. The pH values may impact the protonation of N-CQDs surface functional groups and lead to significant fluorescence quenching of N-CQDs. Therefore, the fluorescence intensity of N-CQDs is the highest at pH 7.0, but it decreases with pH as pH values being either more than or less than pH 7.0. The N-CQDs exhibit high sensitivity to Fe3+ ions, for Fe3+ ions would decrease the fluorescence intensity of N-CQDs by 99.6%, and the influence of Fe3+ ions on N-CQDs fluorescence quenching is slightly affected by other metal ions. Moreover, the fluorescence quenching efficiency of Fe3+ ions displays an obvious linear relationship to Fe3+ concentrations in a wide range of concentrations (up to 200 µM) and with a detection limit of 1.89 µM. Therefore, the generated N-CQDs may be utilized as a robust fluorescence sensor for detecting pH and Fe3+ ions.

Oil Phase Solubility Rather Than Diffusivity Determines the Release of Entrapped Amino Acids and Di-Peptides from Water-in-Oil-in-Water Emulsions

The permeation of amino acids and di-peptides with different hydrophobicities across the oil phase in W/O/W double emulsions was investigated at different concentrations, considering the pH of the aqueous phase. Moreover, the particle size, yield of entrapped water and release kinetics of the double emulsions was evaluated as a function of time. Regarding the release of the entrapped amino acids and di-peptides, their hydrophobicity and the pH had a significant effect, whereas the concentration of the dissolved compound did not lead to different release kinetics. The release of the amino acids and di-peptides was faster at neutral pH as compared to acidic pH values due to the increased solute solubility in the oil phase for more hydrophobic molecules at neutral pH. Regarding the effect of the type of oil, much faster amino acid transport was observed through MCT oil as compared to LCT oil, which might be due to its higher solubility and/or higher diffusivity. As di-peptides released faster than amino acids, it follows that the increased solubility overruled the effect from the decreased diffusion coefficient of the dissolved compound in the oil phase.

effect of adding probiotic bacteria on bauxite waste mud

Bauxite waste sludge is quite dangerous when polluted into the surrounding environment. The number is increasing with the higher mining production. The utilization is still not maximized hence it is unbalanced to the increasing number, and it is necessary to use on a large scale. Sub-grade soil could use a lot of bauxite waste sludge but in reality, this waste is unsafe to use and its characteristics are mud the requirements of bearing capacity according to the AASHTO and USCS Classification unfulfilled. This study aims to determine the effect of the use of probiotic bacteria in bauxite waste on its physical characteristics and pH value. This experimental research method develops test objects according to ASTM standards with the same weight of bauxite waste and variations in the number of probiotic bacteria, namely 25 ml, 50 ml, 75 ml, and 100 ml and the incubation time of bacteria is 7 days, 14 days, 21 days, 28 days, 35 days, and 42 days. The results showed that the test specimens with more bacteria and longer incubation times resulted in lower pH values and physical characteristics that fulfilled the requirements for sub-grade soil.

2-Sulfonylpyrimidines as Privileged Warheads for the Development of S. aureus Sortase A Inhibitors

Staphylococcus aureus is one of the most frequent causes of nosocomial and community-acquired infections, with emerging multiresistant isolates causing a significant burden to public health systems. We identified 2-sulfonylpyrimidines as a new class of potent inhibitors against S. aureus sortase A acting by covalent modification of the active site cysteine 184. Series of derivatives were synthesized to derive structure-activity relationship (SAR) with the most potent compounds displaying low micromolar KI values. Studies on the inhibition selectivity of homologous cysteine proteases showed that 2-sulfonylpyrimidines reacted efficiently with protonated cysteine residues as found in sortase A, though surprisingly, no reaction occurred with the more nucleophilic cysteine residue from imidazolinium-thiolate dyads of cathepsin-like proteases. By means of enzymatic and chemical kinetics as well as quantum chemical calculations, it could be rationalized that the SNAr reaction between protonated cysteine residues and 2-sulfonylpyrimidines proceeds in a concerted fashion, and the mechanism involves a ternary transition state with a conjugated base. Molecular docking and enzyme inhibition at variable pH values allowed us to hypothesize that in sortase A this base is represented by the catalytic histidine 120, which could be substantiated by QM model calculation with 4-methylimidazole as histidine analog.

Correlation of Blood and Salivary pH Levels in Healthy, Gingivitis, and Periodontitis Patients before and after Non-Surgical Periodontal Therapy

Periodontitis is an infectious illness which leads to the inflammation of protective tissues around the teeth and the continuous loss of alveolar bone and conjunctive tissue. Biomarker analysis in serum and saliva helps in the evaluation of disease progression and activity. It is also established that every inflammatory change along with resultant damage of tissues ends up in altered pH values in the fluids and tissues. Aim: To correlate the connection of pH levels in both blood as well as saliva in healthy, periodontitis, and gingivitis patients. Materials and Methods: The current research involved 145 subjects amidst the age of 20 and 55 years. The subjects were split into three different groups: healthy (Group A), gingivitis (Group B), and finally chronic periodontitis (Group C). The recording of clinical parameters was done by gingival index (GI), probing depth (PD), and plaque index (PI). pH of saliva and blood was analyzed with the help of digital single electrode pH meter. Subjects have gone through scaling and root planning (SRP) coupled with the instructions of oral hygiene. They were recalled post 4 weeks, and saliva and blood samples were gathered for analyzing pH. Results: Clinical parameters GI and PI were statistically important in both group C as well as group B post SRP. A crucial change has been observed in attachment levels (AL) and PD in the case of periodontitis group post SRP. The difference in the salivary pH values were significant between group B vs. C and A vs. C before the treatment because the values for group C were acidic, whereas in groups B and A the pH was alkaline. After the treatment, the values were still significant because the pH has become more alkaline compared to preoperative value in both group B and C. Saliva’s pH levels have demonstrated a statistically significant reduction in group C post SRP. Conclusion: Salivary pH levels and blood evidently became alkaline in the group C patients post SRP and there is a positive correlation between them and the clinical parameters.