Polydopamine Nanoparticles as a New and Highly Selective Biosorbent for the Removal of Copper (II) Ions from Aqueous Solutions

The adsorption and desorption of copper (II) ions from aqueous solutions were investigated using polydopamine (PD) nanoparticles. The nanoscale PD nanoparticles with mean diameter of 75?nm as adsorbent were synthesized from alkaline solution of dopamine and confirmed using scanning electron microscopy and X-ray diffraction analysis. The effects of pH (2?C6), adsorbent dosage (0.2?C0.8?g?L^?1), temperature (298?C323?K), initial concentration (20?C100?mg?L^?1), foreign ions (Zn²⁺, Ni²⁺, Cd²⁺, Fe²⁺, and Ag⁺), and contact time (0?C360?min) on adsorption of copper ions were investigated through batch experiments. The isotherm adsorption data were well described by the Langmuir isotherm model. The maximum uptake capacity of Cu²⁺ ions onto PD nanoparticles was found to 34.4?mg/g. The kinetic data were fitted well to pseudo-second-order model. Moreover, the thermodynamic parameters of the adsorption (the Gibbs free energy, entropy, and enthalpy) were studied.     

Predicting youth participation in urban agriculture in Malaysia: insights from the theory of planned behavior and the functional approach to volunteer motivation

This study examines factors associated with the decision of Malaysian youth to participate in a voluntary urban agriculture program. Urban agriculture has generated significant interest in developing countries to address concerns over food security, growing urbanization and employment. While an abundance of data shows attracting the participation of young people in traditional agriculture has become a challenge for many countries, few empirical studies have been conducted on youth motivation to participate in urban agriculture programs, particularly in non-Western settings. Drawing on the theories of planned behavior and the functional approach to volunteer motivation, we surveyed 890 students from a public university in Malaysia about their intention to join a new urban agriculture program. Hierarchical regression findings indicated that the strongest predictor of participation was students’ attitude toward urban agriculture, followed by subjective norms, career motives and perceived barriers to participation. The findings from this study may provide useful information to the university program planners in Malaysia in identifying mechanisms for future students’ involvement in the program.     

Examining the Effects of the Destroying Ammunition,Mines and Explosive Devices on the Presence of Heavy Metals in Soil of Open Detonation Pit; Part 2: Determination of Heavy Metal Fractions

As a result of the destruction of ammunition, mines, and explosive devices by the method of open detonation, the increased concentration of heavy metals is often recorded in the soil of military polygons, which is a serious ecological problem. However, in order to determine the potential risk of such locations to the environment, it is necessary to determine, in addition to the total content, the forms in which the metals are present. In this paper, a sequential extraction method was used to analyze the six fractions of five heavy metals (cadmium, lead, nickel, copper, and zinc) in the soil of the polygon for destruction of ammunition, mines, and explosive devices. Samples were collected from the place of direct detonation (so-called pits) and from the edge of the pit. The aim of this research is determination of metal speciation in order to obtain a better insight in their mobility and risk arising from this. The results showed that heavy metals are predominantly present in the residual, oxide, and organic fractions. Cd and Cu were also significantly present in the mobile fractions due to conducted activities on the polygon. To assess the potential environmental risk of soil, the risk assessment code (RAC) and individual (ICF) and global (GCF) contamination factors were used. According to the RAC, the mobility and bioavailability of the analyzed heavy metals decreases in the following order: Cd?>?Cu?>?Zn?>?Pb?>?Ni. ICF results show low to moderate risk, while GCF results show low risk in terms of heavy metal contamination in the examined area.     

Physicochemical,Nutritional and In Vitro Antidiabetic Characterisation of Blue Whiting (Micromesistius poutassou) Protein Hydrolysates

Protein hydrolysates from low-value underutilised fish species are potential sources of high-quality dietary protein and health enhancing peptides. Six blue whiting soluble protein hydrolysates (BW-SPH-A_F), generated at industrial scale using different hydrolysis conditions, were assessed in terms of their protein equivalent content, amino acid profile and score and physicochemical properties in addition to their ability to inhibit dipeptidyl peptidase IV (DPP-IV) and stimulate the secretion of insulin from BRIN-BD11 cells. Furthermore, the effect of simulated gastrointestinal digestion (SGID) on the stability of the BW-SPHs and their associated in vitro antidiabetic activity was investigated. The BW-SPHs contained between 70–74% (w/w) protein and all essential and non-essential amino acids. All BW-SPHs mediated DPP-IV inhibitory (IC₅₀: 2.12–2.90 mg protein/mL) and insulin secretory activity (2.5 mg/mL; 4.7 to 6.4-fold increase compared to the basal control (5.6 mM glucose alone)). All BW-SPHs were further hydrolysed during SGID. While the in vitro DPP-IV inhibitory and insulin secretory activity mediated by some BW-SPHs was reduced following SGID, the activity remained high. In general, the insulin secretory activity of the BW-SPHs were 4.5–5.4-fold higher than the basal control following SGID. The BW-SPHs generated herein provide potential for anti-diabetic related functional ingredients, whilst also enhancing environmental and commercial sustainability.     

EFFECTS OF SOAKING TEMPERATURE,STRATIFICATION, POTASSIUM NITRATE AND GIBBERELLIC ACID ON SEED GERMINATION OF LOQUAT TREES

The present study was carried out to increase loquat seed germination with treatments consisting of two soaking temperatures (24 ± 2°C and 38 ± 2°C), chemical agents [control, 0.5% potassium nitrate (KNO₃) and 250 mgL^?1 gibberellic acid (GA₃) each for 20 h], and different moist chilling (MC) periods (1, 2, 3 and 4 weeks under 4–5°C). Compared with 24 ± 2°C, soaking at 38 ± 2°C reduced germination%, mean daily germination (MDG), and mean germination time (MGT), plumule and radicle lengths. Germination percentage, days to 50% emergence, fresh weight and lateral root numbers significantly reduced as MC period increased. KNO₃ and GA₃ had no significant effect on germination percentage, MDG, MGT and lateral root numbers. KNO₃ reduced days to 50% emergence and radicle length, but increased fresh weight compared with control and GA₃. Finally, our results suggest the soaking at 24 ± 2°C followed by 0.5% KNO₃ each for 20 h plus 1 week of MC or soaking at 24 ± 2°C followed by 250 mgL^?1 GA₃ each for 20 h plus 2 week of MC.     

Antioxidant Activity and Chemical Characterization of Essential Oil of <Emphasis Type="Italic">Bunium persicum</Emphasis>

The search for natural antioxidants, especially of plant origin, has notably increased in recent years. Bunium persicum Boiss. is an economically important medicinal plant growing wild in the dry temperature regions in Iran. In this study, chemical constituents of the essential oil of the seed from Bunium persicum Boiss. have been studied by GC/MS technique. The major components were caryophyllene (27.81%), gamma-terpinene (15.19%), cuminyl acetate (14.67%). Individual antioxidant assays such as, DPPH* scavenging activity and beta-carotene bleaching have been carried out. In DPPH* system, the EC(50) value of essential oil was determined as 0.88 mg/mL. In beta-carotene bleaching antioxidant activity of essential oil (0.45%) was almost equal to BHT at 0.01%. In addition, the antioxidant activity of the essential oil was evaluated in crude soybean oil by monitoring peroxide and thiobarbituric acid values of the oil substrate. The results showed that the Bunium persicum essential oil (BPEO) was able to reduce the oxidation rate of the soybean oil in the accelerated condition at 60 degrees C (oven test). The essential oil at 0.06% showed the same effect of BHA at 0.02%. Hence, BPEO could be used as an additive in food after screening.     

Characterization of the volatile composition of essential oils of some lamiaceae spices and the antimicrobial and antioxidant activities of the entire oils

The essential oils of Ocimum basilicum L., Origanum vulgare L., and Thymus vulgaris L. were analyzed by means of gas chromatography-mass spectrometry and assayed for their antioxidant and antimicrobial activities. The antioxidant activity was evaluated as a free radical scavenging capacity (RSC), together with effects on lipid peroxidation (LP). RSC was assessed measuring the scavenging activity of the essential oils on 2,2-diphenyl-1-picrylhydrazil (DPPH(*)) and OH(*) radicals. Effects on LP were evaluated following the activities of essential oils in Fe(2+)/ascorbate and Fe(2+)/H(2)O(2) systems of induction. Essential oils exhibited very strong RSCs, reducing the DPPH radical formation (IC(50)) in the range from 0.17 (oregano) to 0.39 microg/mL (basil). The essential oil of T. vulgaris exhibited the highest OH radical scavenging activity, although none of the examined essential oils reached 50% of neutralization (IC(50)). All of the tested essential oils strongly inhibited LP, induced either by Fe(2+)/ascorbate or by Fe(2+)/H(2)O(2). The antimicrobial activity was tested against 13 bacterial strains and six fungi. The most effective antibacterial activity was expressed by the essential oil of oregano, even on multiresistant strains of Pseudomonas aeruginosa and Escherichia coli. A significant rate of antifungal activity of all of the examined essential oils was also exhibited.     

Occupational swine exposure and Hepatitis E virus,Leptospira, Ascaris suum seropositivity and MRSA colonization in Austrian veterinarians, 2017–2018—A cross‐sectional study

We investigated the prevalence of Hepatitis E Virus (HEV), Leptospira and Ascaris suum (A. suum) seropositivity, and of nasal methicillin‐resistant Staphylococcus aureus (MRSA) colonization among Austrian practising veterinarians, and assessed the association with occupational swine livestock exposure. The 261 participants completed a questionnaire on demographics, intensity of occupational swine livestock contact and glove use during handling animals and their secretions. Participants' blood samples were tested for HEV, Leptospira and A. suum seropositivity and nasal swabs cultured for MRSA. We compared swine veterinarians (defined as >3 swine livestock visits/week) to non‐swine veterinarians (≤3 swine livestock visits/week) with regard to the outcomes through calculating prevalence ratio (PR) and 95% confidence interval (CI). Furthermore, the relationship between occupational swine livestock contact and the study outcomes was examined by age (</≥55 years) and glove usage. The prevalence of nasal MRSA colonization was 13.4% (95% CI: 9.3–17.6), of HEV seropositivity 20.8% (95% CI: 15.8–25.7) and A. suum seropositivity 44% (95% CI: 37.7–50.2). The highest anti‐leptospiral antibodies titres were 1:200 (L. hebdomadis) and 1:100 (L. autumnalis, L. caicola) found in three non‐swine veterinarians. Compared to non‐swine veterinarians, swine veterinarians were 1.9 (95% CI: 1.0–3.4) and 1.5 (95%CI: 1.0–2.3) times more likely HEV seropositive and A. suum seropositive, respectively, and 4.8 (95%CI: 2.5; 9.3) times more likely nasally colonized with MRSA. Among glove‐using veterinarians, occupational swine contact was no longer a determinant for HEV seropositivity (PR 1.6; 95% CI: 0.8–2.9). Similar was found for A. suum seropositivity, which was no longer associated with occupational swine livestock contact in the subgroup of glove using, ≥55‐year‐old veterinarians (PR: 1.07; 95% CI: 0.4–3.3). Our findings indicate that >3 occupational swine livestock visits per week is associated with HEV and A. suum seropositivity and nasal MRSA colonization and that glove use may play a putative preventive role in acquiring HEV and A. suum. Further analytical epidemiological studies have to prove the causality of these associations.