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A layered nanoelectrode design was based on the high surface area of graphene oxide and reduced graphene oxide; these layers were decorated with n/p-type palladium oxide nanoparticles (NPs) and cadmium sulfide NPs. The building of electron transfer through n/p-type eases the movement of electrons and increases electron clouds for the supercapacitor efficiency of fabricated nanoelectrodes, and their electrochemical characteristics were investigated using electrochemical impedance spectroscopy (EIS) data. Applications as supercapacitors and other energy storage devices were supported by the construction, development, and surface modification of electron transport that was measured by EIS. The values of capacitance detected for GO@PdO@rGO (16.4 μF cm−2) and GO@PdO@rGO.CdS (21 μF cm−2) refer to the improvement in the electron transfer by the unique electrode. At 100 cycles, the capacitance retention of the nanoelectrodes was measured via a cyclovoltammetry device to reveal the high stability of GO@PdO@rGO (96%) and GO@PdO@rGO.CdS (97%) compared to the other electrode. The electroactive mass was determined to be 0.3396 mF cm−2 for GO@PdO@rGO and 0.426 mF cm−2 for GO@PdO@rGO.CdS; the electrochemical surface area (ECSA) was calculated to be 1007.8 for GO@PdO@rGO and 3058.5 for GO@PdO@rGO.CdS. The study suggests that these novel fabricated nanoelectrodes provide high efficiency for supercapacitors, batteries, water desalination, and energy storage, so they are promising candidate nanoelectrodes for energy applications. [ABSTRACT FROM AUTHOR]

Cellulosic date palm wastes may have beneficial biotechnological applications for eco-friendly utilization. This study reports the isolation of thermophilic cellulase-producing bacteria and their application in lactic acid production using date palm leaves. The promising isolate was identified as Paenibacillus alvei by 16S rRNA gene sequencing. Maximum cellulase production was acquired using alkaline treated date palm leaves (ATDPL) at 48 h and yielded 4.50 U.mL-1 FPase, 8.11 U.mL-1 CMCase, and 2.74 U.mL-1 β-glucosidase. The cellulase activity was optimal at pH 5.0 and 50°C with good stability at a wide temperature (40-70°C) and pH (4.0-7.0) range, demonstrating its suitability in simultaneous saccharification and fermentation. Lactic acid fermentation was optimized at 4 days, pH 5.0, 50°C, 6.0% cellulose of ATDPL, 30 FPU/ g cellulose, 1.0 g. L-1 Tween 80, and 5.0 g. L-l yeast extract using Lactobacillus delbrueckii. The conversion efficiency of lactic acid from the cellulose of ATDPL was 98.71%, and the lactic acid productivity was 0.719 g. L-1 h-1. Alkaline treatment exhibited a valuable effect on the production of cellulases and lactic acid by reducing the lignin content and cellulose crystallinity. The results of this study offer a credible procedure for using date palm leaves for microbial industrial applications.

A reduction in crop spoilage and an increase in shelf-life is the goal of effective disease control methods. This study aimed to assess ZnO-nanoparticles (ZnO-NPs) as a safe, new protectant against Rhizopus soft rot of sweet potato. ZnO-NPs had a fungicidal effect against Rhizopus stolonifer when used at concentrations above 50 ppm. The results showed that tubers treated with ZnO-NPs exhibited fewer fungal populations (1.2 CFU per segment) than those that did not receive the treatment. Tubers infected with Rhizopus stolonifer and treated with ZnO-NPs showed no visible decay for up to 15 days, indicating that ZnO-NPs act as a coating layer on tuber surface. The greatest weight loss after 15 days of storage was reported in infected tubers (8.98%), followed by infected tubers treated with ZnO (6.54%) and infected tubers treated with ZnO-NPs (3.79%). The activity of cell-wall degrading enzymes, α-amylase and cellulase, were significantly increased in both infected tubers and those treated with ZnO, compared to the tubers treated with ZnO-NPs. These results confirm that coating with ZnO-NPs is an effective method of protecting sweet potato tubers from infection, maintaining their quality and increasing their shelf-life for up to 2 months in storage.

This review delves into the mesmerizing technology of nano-agrochemicals, specifically pesticides and herbicides, and their potential to aid in the achievement of UN SDG 17, which aims to reduce hunger and poverty globally. The global market for conventional pesticides and herbicides is expected to reach USD 82.9 billion by 2027, growing 2.7% annually, with North America, Europe, and the Asia–Pacific region being the biggest markets. However, the extensive use of chemical pesticides has proven adverse effects on human health as well as the ecosystem. Therefore, the efficacy, mechanisms, and environmental impacts of conventional pesticides require sustainable alternatives for effective pest management. Undoubtedly, nano-agrochemicals have the potential to completely transform agriculture by increasing crop yields with reduced environmental contamination. The present review discusses the effectiveness and environmental impact of nanopesticides as promising strategies for sustainable agriculture. It provides a concise overview of green nano-agrochemical synthesis and agricultural applications, and the efficacy of nano-agrochemicals against pests including insects and weeds. Nano-agrochemical pesticides are investigated due to their unique size and exceptional performance advantages over conventional ones. Here, we have focused on the environmental risks and current state of nano-agrochemicals, emphasizing the need for further investigations. The review also draws the attention of agriculturists and stakeholders to the current trends of nanomaterial use in agriculture especially for reducing plant diseases and pests. A discussion of the pros and cons of nano-agrochemicals is paramount for their application in sustainable agriculture. [ABSTRACT FROM AUTHOR]

Hydrolytic enzyme production by thermophilic bacteria isolated from hot springs in the southern region of Saudi Arabia was investigated. The physical and chemical properties of the hot springs prove to be an important environment for hydrolytic-enzyme-producing thermophilic bacteria. Eighty-four bacterial isolates were obtained from three hot springs: Al-Majardah, Al-Khubah and Al-Ardah. Screening of the isolates for enzyme production indicated that 78 isolates showed activity for one or more enzymes. Molecular identification and phylogenic analysis of selected promising isolates confirmed the identity of the isolates as Bacillus aerius, Bacillus licheniformis and Bacillus sonorensis, which have potential to produce the target enzymes α-amylase, protease and lipase, respectively. Optimization of hydrolytic enzyme production by bacterial strains was investigated using kitchen waste as a cheap carbon energy source. Maximum enzyme production was achieved after 72 hours of incubation at the beginning of the stationary phase of growth. Enzyme production was dependent on the initial pH value in the range of pH 7.5-8.5 and an optimal incubation temperature of between 55-60°C. Enzyme production increased gradually in proportion to the kitchen waste concentration; whereas maximum lipase production was gained at 5.0% (w/v) kitchen waste, 7.0% (w/v) of waste was optimal for both α-amylase and protease productivity. The results indicated that hot springs in Saudi Arabia are a substantial source of thermophilic bacteria producing industrially important enzymes using cheap and unexploited waste.

Approximately 33% of the arable land around the world is vulnerable to drought, which is a very serious issue affecting the yield and productivity of cereal crops. Two contrasting rice (Oryza sativa L.) genotypes, HTT-138 (drought tolerant) and (HTT-39 drought-sensitive), under various levels of water treatments, i.e. control flooded (CF) as recommended for rice (control), control saturated (CS) 100% field capacity (FC), 80% FC, and 60% FC without or with foliar spray (100 mg L–1) of salicylic acid (SA) evaluated to enhance the yield for food security. The results showed that leaf gas exchange parameters, water use efficiency and water related parameters reduced under all levels of water deficient conditions. Drought stress increased oxidative stress (superoxide anions and hydrogen peroxide) and decreased after foliar spray of SA due to enhancement in antioxidant activity (catalase, ascorbate peroxidase, peroxidase, superoxide dismutase). Ascorbic acid, total soluble protein, total soluble sugar, total phenolics, proline, anthocyanin, salicylic acid, and amylase activity were reduced under drought stress and increased after foliar spray of SA. HTT-138 showed more tolerance to the drought stress than HTT-39 under the same levels of water deficient conditions. Although drought-stress was ameliorated by the foliar spray of SA which not only increased plant growth, dry weight, and metabolism or metabolic activities but also increased the nutritional status of the plant by decreasing the concentration of reactive oxygen species (ROS) in the membranous bounded organelles. In conclusion, the foliar spray of SA is useful to enhance plant growth and yield in cereal crops especially those grown in abiotic stress environments. [ABSTRACT FROM AUTHOR]

Cellulases have a potential for use in biotechnology and industry such as in starch processing, alcoholic beverage manufacture, malting and brewing, clarification of juice, pulp bleaching, textile manufacturing and animal feed production. Thirty one thermophilic and cellulolytic bacteria were successfully isolated from a southern region of Saudi Arabia. The phylogenetic analysis of the promising isolate using its 16S rDNA sequence data showed its highest homology (99%) with Geobacillus stearothermophilus. The analysis was performed to evaluate cellulase production using untreated and both alkaline and acid-steam treated date palm wastes as carbon sources. The optimal conditions for cellulase production consisted of a 2.5% alkaline-treated date palm leaf base with pH at 7.0 - 7.5, a cultivation temperature at 45-50°C, an agitation rate of 200 rpm, and 0.2% Tween 80 and yeast extract as a best nitrogen source when fermentation was extended up to 48h. The results indicated that the utilization of date palm waste as a cheap substrate for the production of cellulases had potential, and could reduce environment pollution. [ABSTRACT FROM AUTHOR]