Magnetic nanocomposite of maize offal biomass for effective sequestration of Congo red and methyl orange dyes from contaminated water: modeling, kinetics and reusability.

The current study aims to use a facile and novel method to remove Congo red (CR) and Methyl Orange (MO) dyes from contaminated water with Maize offal biomass (MOB) and its nanocomposite with magnetic nanoparticles (MOB/MNPs). The MOB and MOB/MNPs were characterized with Fourier-transform infrared (FTIR), scanning electron microscopy (SEM), BET, XRD and point of zero charge (pHPZC). The influence of initial CR and MO levels (20-320 mg/L), adsorbent dosage (1-3 g/L), pH (3-9), co-exiting ions, temperature (25-45 °C) and time (15-180 min) was estimated. The findings demonstrated that MOB/MNPs exhibited excellent adsorption of 114.75 and 29.0 mg/g for CR and MO dyes, respectively while MOB exhibited 81.35 and 23.02 mg/g adsorption for CR and MO dyes, respectively at optimum pH-5, and dose 2 g/L. Initially, there was rapid dye removal which slowed down until equilibrium was reached. The interfering/competing ions in contaminated water and elevated temperature favored the dyes sequestration. The MOB/MNPs exhibited tremendous reusability and stability. The dyes adsorption was spontaneous, and exothermic with enhanced randomness. The adsorption effects were well explained with Freundlich model, pseudo second order and Elovich models. It is concluded that MOB/MNPs showed excellent, eco-friendly, and cost-effective potential to decontaminate the water.

Nanocomposite of Maize offal biomass demonstrated higher dyes removal.FTIR, SEM, BET, XRD and pH_PZC provided vital evidence for dyes adsorption.MOB/MNPs displayed excellent stability and reusability for dyes adsorption.Groundwater samples exposed a higher dyes removal.Results were validated with equilibrium and kinetic adsorption models.

Food waste: causes and economic losses estimation at household level in Pakistan.

Food waste is one of the major sustainability issues that need to be addressed due to its negative impacts on the economy, environment, and food security. To develop food waste reduction policies on regional and global level, it is mandatory to have a clear understanding of the various factors prompting food waste at household level and the extent of the economic losses incurred by food waste. Reducing food waste can decrease household expenditure on food, freeing resources for health, education, and well-being. The current study was aimed to (1) examine the food waste behavior of the respondents and to (2) determine the level of monetary losses from food waste. To address these objectives, a questionnaire survey and sample of food waste generated during 24 h were collected from 51 households in Tehsil Kahror Pakka, District Lodhran, Punjab, Pakistan. The survey focus was on levels of food waste and respondents' knowledge and behaviors about food waste. Economic estimation of food waste was also done. In the survey, respondents from both high- and low-income households revealed that their fruit and vegetables (31%; 32%) and peel and scrap (53%; 48%) losses were higher while egg losses (4%; 4%) were lower among various food waste categories. Wanting to eat fresh food and having no time to save food were the reasons for food waste. Monetary losses from food waste (US$ 12.8/Rs. 3677.01 per capita per annum) were higher in high-income households compared to low-income households.

Biowaste-based sorbents for arsenic removal from aqueous medium and risk assessment.

Water contamination by arsenic (As) is widespread and is posing serious health threats globally. Hence, As removal techniques/adsorbents need to be explored to minimize potentials hazards of drinking As-contaminated waters. A column scale sorption experiment was performed to assess the potential of three biosorbents (tea waste, wheat straw and peanut shells) to remove As (50, 100, 200 and 400 µg L-1) from aqueous medium at a pH range of 5-8. The efficiency of agricultural biosorbents to remove As varies greatly regarding their type, initial As concentration in water and solution pH. It was observed that all of the biosorbents efficiently removed As from water samples. The maximum As removal (up to 92%) was observed for 400 µg L-1 initial As concentration. Noticeably, at high initial As concentrations (200 and 400 µg L-1), low pH (5 and 6) facilitates As removal. Among the three biosorbents, tea waste biosorbent showed substantial ability to minimize health risks by removing As (up to 92%) compared to peanut shells (89%) and wheat straw (88%). Likewise, the values of evaluated risk parameters (carcinogenic and non-carcinogenic risk) were significantly decreased (7-92%: average 66%) after biosorption experiment. The scanning electron microscopy, Fourier transform infrared spectroscopy, energy-dispersive X-ray and X-ray diffraction analyses confirmed the potential of biosorbents to remediate As via successful loading of As on their surfaces. Hence, it can be concluded that synthesized biosorbents exhibit efficient and ecofriendly potential for As removal from contaminated water to minimize human health risk.

Relationship Between Mass Loss and Fruit Quality of Sweet Orange at Two Different Storage Conditions.

Mass loss from fresh produce is linked to a reduction of its aesthetic value. However, a relationship between mass loss and biochemical quality parameters at different storage conditions has not been widely explored. Therefore, the current study is designed with the objectives to determine the behavior of fruit quality parameters and a relationship between fruit mass loss and fruit quality at two different storage conditions. Sweet orange fruit stored in a zero energy cool chamber (ZECC) had greater shelf-life of more than 15 days, fruit size (62.40 mm) and peel (35.15%) and lower mass loss (4.94%), juice (32.19%) and electrical conductivity (EC) (2.06 S/m) as compared to ambient conditions in laboratory during 25 days of storage. In ZECC, only EC was positively correlated (r = 0.57) with mass loss, whereas at room temperature EC (r = 0.76), total soluble solids (TSS) (r = 0.60) and fruit internal temperature (r = 0.64) were positively and peel (%) (r = -0.52) and fruit diameter (r = -0.49) were negatively correlated with mass loss. Correlation of combined storage conditions revealed that EC (r = 0.47) and TSS (r = 0.50) were positively and peel (%) (r = -0.77) and fruit diameter (r = -0.55) were negatively correlated with mass loss (%). The principal component analysis (PCA) revealed that the scores of room temperature were strongly associated with TSS, pH, EC, mass loss (%), juice (%) and internal temperature (°C), whereas scores of ZECC were strongly associated with pulp (%), ascorbic acid (mg 100 mL-1), acidity (%), and fruit diameter (mm).

Cadmium Partitioning, Physiological and Oxidative Stress Responses in Marigold (Calendula calypso) Grown on Contaminated Soil: Implications for Phytoremediation.

Marigold (Calendula calypso) is a multipurpose ornamental plant, but its cadmium (Cd) tolerance and phytoremediation potential is unknown. The proposed study was carried out to unravel Cd partitioning, physiological and oxidative stress responses of C. calypso grown under Cd stress. Plants were grown for four months in pots having different soil Cd levels: 0, 25, 50, 75, and 100 mg kg-1 soil. Plant growth, biomass, photosynthetic pigments, leaf water contents, stomatal conductance, and membrane stability index were not decreased at 25 mg kg-1 Cd. At higher levels of Cd stress, activities of antioxidant enzymes (SOD, APX, CAT, POD) increased to mitigate H2O2 and lipid peroxidation. Cadmium uptake in plants increased with increasing soil Cd levels, and roots accumulated a greater portion of Cd, followed by shoots and flowers, respectively. On the basis of Cd accumulation and its tolerance, it was determined that C. calypso can be successfully grown for phytostabilization of Cd contaminated soils.

Synergistic effects of bismuth coupling on the reactivity and reusability of zerovalent iron nanoparticles for the removal of cadmium from aqueous solution.

Removal of cadmium (Cd2+), a highly toxic heavy metal, from aqueous solutions was investigated using nano zerovalent iron (Fe0). Cadmium was efficiently removed by Fe0, although reactivity and reusability of Fe0 was significantly promoted by coupling with bismuth (Bi). At a reaction time of 20 min, 85% and 96% Cd2+ was removed by Fe0 and Bi/Fe0, respectively, at first cycle using [Cd2+]0 = 10 mg/L and [Fe0]0 = [Bi/Fe0]0 = 1.0 g/L. However, Cd2+ removal efficiency was reduced to 12% and 80% at sixth cycle by Fe0 and Bi/Fe0, respectively. The X-Ray diffraction and energy dispersive X-Ray spectroscopy analysis proved successful formation of Fe0 by the chemical reduction method and also confirmed coupling of Bi with Fe0 to form bimetallic Bi/Fe0. The oxidation of Fe0 and Bi/Fe0 yielded electron that played significant role in the conversion of toxic Cd2+ into non-toxic Cd0. The reactivity of electron with Cd2+ was calculated to be 4.3 × 109 M-1 s-1. The pH of solution showed pronounced effects on the reactivity of both Fe0 and Bi/Fe0. Removal of Cd2+ by both Fe0 and Bi/Fe0 followed pseudo-first-order kinetic model. The conversion of Cd2+ into non-toxic Cd0 proved Fe0 and Bi/Fe0 to be highly efficient and rewarding in detoxification of Cd2+ and other toxic metals in aqueous environments.

Greener synthesis of zinc oxide nanoparticles using Trianthema portulacastrum extract and evaluation of its photocatalytic and biological applications.

Synthesis of nanoparticles (NPs) through "green" chemistry is an exciting area of research with wide applications. Trianthema portulacastrum's extract containing greater amount of reducing agents has been explored first time for the synthesis of ZnO-NPs that characterized with UV/Vis, XRD, FT-IR, SEM,EDX, HR-TEM and XPS. The particles of ZnO-NPs are crystalline and having the size in the range of 25-90 nm. The cell viability of ZnO-NPs was studied using Mouse pre-osteoblast cell line MC3T3-E1 sub-clone 14 cells which confirmed its biocompatibility that render for biomedical applications. The antibacterial properties were evaluated against Staphylococcus aureus and Escherichia coli which showed high potency of synthesized ZnO-NPs against these species. The antifungal activities of ZnO-NPs were screened against Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus of fungal species. The antioxidant activity of the as-synthesized NPs was also studied using DPPH (2, 2-diphenyl-1-picrylhydrazyl) substrate. The ZnO-NPs were evaluated for catalytic activity through degradation of Synozol Navy Blue-KBF textile dye using solar irradiation that causes 91% degradation of the dye in 159 min. Mechanistic pathways for the degradation of Synozol Navy Blue-KBF dye using ZnO-NPs were also proposed from the pattern of the degradation of the dye and the resulting by-products. The results concluded that the ZnO-NPs synthesized by green method have high biological and photocatalytic applications.