ABSTRACT
Chemical fungicides are the backbone of modern agriculture, but an alternative formulation is necessary for sustainable crop production to address human health issues and soil/water environmental pollution. So, a green chemistry approach was used to form guar gum nanoemulsions (NEs) of 186.5-394.1 nm containing the chemical fungicide mancozeb and was characterized using various physio-chemical techniques. An 84.5% inhibition was shown by 1.5 mg/mL mancozeb-loaded NEs (GG-1.5) against A. alternata, comparable to commercial mancozeb (86.5 ± 0.7%). The highest mycelial inhibition was exhibited against S. lycopersici and S. sclerotiorum. In tomatoes and potatoes, NEs showed superior antifungal efficacy in pot conditions besides plant growth parameters (germination percentage, root/shoot ratio and dry biomass). About 98% of the commercial mancozeb was released in just two h, while only about 43% of mancozeb was released from nanoemulsions (0.5, 1.0 and 1.5) for the same time. The most significant results for cell viability were seen at 1.0 mg/mL concentration of treatment, where wide gaps in cell viability were observed for commercial mancozeb (21.67%) and NEs treatments (63.83-71.88%). Thus, this study may help to combat the soil and water pollution menace of harmful chemical pesticides besides protecting vegetable crops.
ABSTRACT
Pearl millet is an underutilized and drought-resistant crop that is mainly used for animal feed and fodder. Starch (70%) is the main constituent of the pearl millet grain; this starch may be a good substitute for major sources of starch such as corn, rice, potatoes, etc. Starch was isolated from pearl millet grains and modified with different physical treatments (heat-moisture (HMT), microwave (MT), and sonication treatment (ST)). The amylose content and swelling capacity of the starches decreased after HMT and MT, while the reverse was observed for ST. Transition temperatures (onset (To), peak of gelatinization (Tp), and conclusion (Tc)) of the starches ranged from 62.92-76.16 °C, 67.95-81.05 °C, and 73.78-84.50 °C, respectively. After modification (HMT, MT, and ST), an increase in the transition temperatures was observed. Peak-viscosity of the native starch was observed to be 995 mPa.s., which was higher than the starch modified with HMT and MT. Rheological characteristics (storage modulus (G') and loss modulus (G'')) of the native and modified starches differed from 1039 to 1730 Pa and 83 to 94 Pa; the largest value was found for starch treated with ST and HMT. SEM showed cracks and holes on granule surfaces after HMT as well as MT starch granules. Films were prepared using both native and modified starches. The modification of the starches with different treatments had a significant impact on the moisture, transmittance, and solubility of films. The findings of this study will provide a better understanding of the functional properties of pearl millet starch for its possible utilization in film formation.
ABSTRACT
The nanoparticles for the preparation of nanocomposite starch films were synthesized from potato starch using the acid hydrolysis method. The films were prepared by incorporating starch nanoparticles into the film formulation at 0.5, 1, 2, 5, and 10% level of total starch. The control starch film was prepared without the incorporation of starch nanoparticles (SNPs) in film formulation. The starch and SNPs were analyzed for physicochemical and morphological properties. The absorption capacity of SNPs for water and oil was significantly (p < 0.05) lower as compared to native starch. Whereas, the swelling power and solubility of SNPs were significantly (p < 0.05) higher than the swelling power and solubility of starch, respectively. The starch granules were oval and spherical with regular surfaces whereas the SNPs had irregular cracked exteriors spaces. The water vapor transmission rate (WVTR) from nanocomposite starch films was significantly (p < 0.05) lower than the control starch film. The burst strength of films was increased significantly (p < 0.05) with an increased level of SNPs incorporation in film formulation. The incorporation of SNPs increased film thickness and biodegradability. Thus, the present study revealed that the incorporation of SNPs in film formulation resulted in improved film properties.
Subject(s)
Nanocomposites , Nanoparticles , Solanum tuberosum/chemistry , Starch/isolation & purification , Acids/chemistry , Hydrogen-Ion Concentration , Hydrolysis , Solubility , Soybean Oil/chemistry , Surface Properties , Tensile Strength , Water/chemistryABSTRACT
In recent years, interdisciplinary research is more focused on particle size, which helps in exploring the relation between micro and macroscopic properties of various materials. Starch nanoparticles are generally synthesized by using acid/enzymatic hydrolysis, gamma irradiation, simple nanoprecipitation, ultra-sonication, and homogenization treatments. The properties like amylose content, pasting, rheological, morphological, size distribution, etc. are affected after the formation of nanoparticles from starch. This study emphasizes how various properties are changed in starch nanoparticles. Starch nanoparticles are mainly used in the formulation of nano-emulsion, nano starch-based composite film, and drug delivery. The impact on various native starch properties after the preparation of starch nanoparticles are less reported. So, all the aspects related to various starch properties and their nanoparticles are extensively reviewed in this study so that the listed findings can be utilized in future processes to increase the various foods and non-food utilization of starch nanoparticles.
