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The potential of organic wastes in eliminating old-aged petroleum pollution in saline soils: A case study in Khuzestan province
2023
Jafari Vafa, Hanye | Pourbabaee, Ahmad Ali | Alikhani, Hossein Ali | Yazdanfar, Najmeh | Khanali, Majid
Petroleum contains carcinogens and toxic substances that can have an unfavorable impact on environmental quality and human health when the soil becomes contaminated with crude oil. BBiostimulation and bioaugmentation are the main strategies in the bioremediation of oil-contaminated soils. To decompose old-aged petroleum pollution in saline soil, a full factorial experiment was utilized. The experiment was designed using a completely randomized design with four factors: bacterial inoculum, sugarcane bagasse, chemical fertilizer, and molasses. The application of these factors was conducted in four separate experiments: pretreatment of agricultural soil and spent mushroom compost, pretreatment of spent mushroom compost, pretreatment of agricultural soil, and no pretreatment. After a 60-day incubation period at 28 ˚C, the results showed that the organic wastes of molasses and spent mushroom compost in combination with bacterial inoculum reduced total petroleum hydrocarbons 38 and 33.3%, respectively. Molasses had a considerable impact on increasing the efficiency of bacterial inoculum 1 and bacterial inoculum 3. Similarly, spent mushroom compost was found to significantly affect bacterial inoculum 1. In addition, bagasse was observed to accelerate the bioremediation process by improving the physical conditions of the soil. In the pretreatment of agricultural soil, bagasse in combination with bacterial inoculum 1 and chemical fertilizer reduced the total petroleum hydrocarbons significantly (38%) compared to the control treatment. These results highlight the effectiveness of organic wastes as biostimulation agents in promoting the growth and reproduction of the soil microbial community, as well as establishing the bacterial inoculum.
Show more [+] Less [-]Bioremediation of 1,2-dichloroethane contaminated groundwater: Microcosm and microbial diversity studies
2015
Wang, S.Y. | Kuo, Y.C. | Huang, Y.Z. | Huang, C.W. | Kao, C.M.
In this study, the effectiveness of bioremediating 1,2-dichloroethane (DCA)-contaminated groundwater under different oxidation–reduction processes was evaluated. Microcosms were constructed using indigenous bacteria and activated sludge as the inocula and cane molasses and a slow polycolloid-releasing substrate (SPRS) as the primary substrates. Complete DCA removal was obtained within 30 days under aerobic and reductive dechlorinating conditions. In anaerobic microcosms with sludge and substrate addition, chloroethane, vinyl chloride, and ethene were produced. The microbial communities and DCA-degrading bacteria in microcosms were characterized by 16S rRNA-based denatured-gradient-gel electrophoresis profiling and nucleotide sequence analyses. Real-time polymerase chain reaction was applied to evaluate the variations in Dehalococcoides spp. and Desulfitobacterium spp. Increase in Desulfitobacterium spp. indicates that the growth of Desulfitobacterium might be induced by DCA. Results indicate that DCA could be used as the primary substrate under aerobic conditions. The increased ethene concentrations imply that dihaloelimination was the dominate mechanism for DCA biodegradation.
Show more [+] Less [-]Application of beet sugar byproducts improves sugar beet biofortification in saline soils and reduces sugar losses in beet sugar processing
2021
Alotaibi, Fahad | Bamagoos, Atif A. | Ismaeil, Fekry M. | Zhang, Wenying | Abou-Elwafa, Salah Fatouh
Improving the chemical and physical properties of saline soils is crucial for the sustainable production of sugar beet and efficient processing of beet sugar. Here, the impacts of the application of treated filter cake on sugar beet biofortification under saline soil and sugar losses into molasses during beet sugar processing were evaluated for the first time. The application of treated filter cake significantly reduced K%, Na%, and α-amino-N while enhanced sucrose content and quality index of beet root juice. Consequently, sugar loss percentage, sugar loss yield, and relative sugar loss yield were reduced, whereas recoverable sugar yield was enhanced. Linear regression analysis revealed that quality index and sugar loss yield were increased, whereas sugar loss percentage and relative sugar loss yield were reduced in response to the reduction of soil Na⁺ content accompanied with increasing Ca²⁺ content in the soil increased. The results provide treated filter cake as a promising amendment for saline soil remediation for improving biofortification of sugar beet and reducing sugar losses during beet sugar processing.
Show more [+] Less [-]Ex situ remediation of sediment from Serbia using a combination of electrokinetic and stabilization/solidification with accelerated carbonation treatments
2021
Popov, Nenad | Rončević, Srđan | Duduković, Nataša | Krčmar, Dejan | Mihaljev, Željko | Živkov Baloš, Milica | Đorđievski, Stefan
The application of three simple and cost-effective technologies for ex situ remediation of the sediment of Begej River in Serbia is presented in this paper. In the first step, conventional electrokinetic treatment (EK) was carried out to reduce the amount of contaminated sediment and enhance the accumulation of metals. Subsequently, stabilization/solidification (S/S) treatment was applied to the remaining portion of polluted sediment to immobilize the accumulated metals. At the same time, the influence of accelerated carbonation on the effectiveness of the treatment was evaluated. The immobilizing agents used in this study included bio ash produced by combustion of wheat and soy straw mixture and bio ash derived from molasses incineration. After the treatments, the risk assessment was performed by using the sequential extraction procedure (SEP) and TCLP and DIN 3841-4 S4 leaching tests. The results obtained after the EK treatment revealed a reduction in the amount of polluted sediment to a half. Leaching tests and SEP performed on S/S mixtures after a 28-day maturation period indicated that accelerated carbonation decreased the mobility of critical metals, especially in wheat and soy straw mixtures. Moreover, based on the leaching tests, all prepared mixtures were categorized as non-hazardous and safe for disposal according to the relevant Serbian regulations. The newly developed method that combines EK and S/S treatments with the addition of accelerated carbonation produced reduced volumes of stabilized sediment which is safe for disposal.
Show more [+] Less [-]Environmental and economic analysis of bioethanol production from sugarcane molasses and agave juice
2021
Parascanu, Maria Magdalena | Sanchez, Nestor | Sandoval-Salas, Fabiola | Carreto, Carlos Mendez | Soreanu, Gabriela | Sanchez-Silva, Luz
In this article, sugarcane molasses and agave juice were compared as potential feedstocks for producing bioethanol in Mexico in terms of their environmental impact and economic factors. Life cycle assessment (LCA) using SimaPro was carried out to calculate environmental impacts by using a cradle-to-gate approach. A preliminary economic analysis was performed to determine the economic feasibility of the studied options. Also, capital goods costs were obtained using the Aspen Plus economy package. Moreover, a sensitivity analysis was involved to compare the environmental and economic viability of producing bioethanol from sugarcane molasses and agave juice. LCA results revealed that cultivation and fermentation were the most harmful stages when producing bioethanol from sugarcane molasses and agave juice, respectively. Furthermore, when it was derived from agave juice rather than sugarcane molasses, it had more environmental benefits. This was ascribed to the lower consumption rate of fertilizers, pesticides, and emissions given off from the former. Regarding financial aspects, the preliminary analysis showed that producing bioethanol was not economically viable when grid energy alone was used. However, if power from the grid is partially replaced with renewable energy, producing bioethanol becomes economically feasible, and sugarcane molasses is the most suitable feedstock.
Show more [+] Less [-]Recycling of beet sugar byproducts and wastes enhances sugar beet productivity and salt redistribution in saline soils
2021
Aljabri, Maha | Alharbi, Saif | Al-Qthanin, Rahmah N. | Ismaeil, Fekry M. | Chen, Jiana | Abou-Elwafa, Salah Fatouh
Soil salinity adversely affects the growth, yield, and quality parameters of sugar beet, leading to a reduction in root and sugar yields. Improving the physical and chemical properties of salt-affected soils is essential for sustainable cultivation and sugar beet production. A field experiment was conducted at the Delta Sugar Company Research Farm, El-Hamool, Kafr El-Sheikh, Egypt, to evaluate the response of sugar beet to the application of beet sugar filter cake treated with sulfuric and phosphoric acid-treated, phosphogypsum (PG), desaline, humic acid, and molasses under saline soil conditions. The application of treated filter cake enhanced root length, diameter, and leaf area. The application of molasses enhanced root length, diameter, and leaf area as well. Application of molasses increased sugar content and root yield. The application of either treated filter cake or molasses produced the highest recoverable sugar yield. Linear regression analysis revealed that the root yield, quality index, and recoverable sugar yield increased in response to the increased availability of either Ca²⁺ or K content in the soil which increases in response to the application of soil amendments and molasses. The application of treated beet sugar filter cake and molasses increased the calcium, magnesium, and potassium availability in the soil. Treated filter cake is a promising organic soil amendment that enhanced the yield by 29% and yield-related traits of sugar beet by improving the physical and chemical properties of the soil.
Show more [+] Less [-]Molasses melanoidin promotes copper uptake for radish sprouts: the potential for an accelerator of phytoextraction
2016
Hatano, Kenʼichi | Kanazawa, Kazuki | Tomura, Hiroki | Yamatsu, Takeshi | Tsunoda, Kin-ichi | Kubota, Kenji
Phytoextraction has been proposed as an alternative remediation technology for heavy metal contamination, and it is well known that chelators may alter the toxicity of heavy metals and the bioavailability in plants. Our previous work demonstrated that an adsorbent-column chromatography can effectively separate melanoidin-like product (MLP) from sugarcane molasses. The aim of this study was to examine the chelating property of MLP and to evaluate the facilitatory influence on the phytoextraction efficiency of Japanese radish. The result showed that MLP binds to all the metal ions examined and the binding capacity of MLP toward Cu²⁺ seems to be the highest among them. The metal detoxification by MLP followed the order of Pb²⁺ > Zn²⁺ > Ni²⁺ > Cu²⁺ > Fe²⁺ > Cd²⁺ > Co²⁺. Furthermore, in the phytoextraction experiment using copper sulfate, the application of MLP accelerated the detoxification of copper and the bioavailability in radish sprouts. Thus, these results suggest that MLP possesses the potential for an accelerator of phytoextraction in the copper-contaminated media.
Show more [+] Less [-]Biotreatment of Melanoidin-Containing Distillery Spent Wash Effluent by Free and Immobilized Aspergillus oryzae MTCC 7691
2013
Chavan, M. N. | Dandi, N. D. | Kulkarni, M. V. | Chaudhari, A. B.
A total of three fungal isolates from samples collected at spent wash disposal area were screened for their ability to degrade melanoidin. Distillery molasses spent wash was decolorized, and its chemical oxygen demand (COD) was reduced in immobilized fungal bioreactor (IFB) in the absence of carbon and nitrogen source using fungal mycelia of Aspergillus oryzae MTCC 7691. Fungal mycelia immobilized on baggase packed in a glass column under a batch-wise mode (1) effected removal of 75.71 +/- 0.12 % color, 51.0 +/- 0.13 % biological oxygen demand (BOD), 86.19 +/- 2.56 % COD, and 49.0 +/- 0.12 % phenolic pigments of distillery spent wash up to 25 days at 30 degrees C, while free fungal mycelia resulted in removal of 63.1 +/- 0.16 % color, 27.74 +/- 0.14 % BOD, 76.21 +/- 1.62 % COD, and 37.32 +/- 0.17 % phenolic pigments of distillery spent wash using shake flask, (2) manganese peroxidase (MnP) activity was highest (1.55 +/- 0.01 U ml(-1) min(-1)) in immobilized fungi, followed by lignin peroxidase (0.65 +/- 0.01 U ml(-1) min(-1)) and laccase activity (0.9 +/- 0.01 CU ml (1) min (1)), (3) accumulative MnP activity was highly correlated with (r=0.9216) spent wash decolorization and (r=0.7282) reduction of phenolic pigments, suggesting the presence of MnP activities in bioremediation of spent wash and (4) degradation of spent wash was confirmed by high-performance thin layer chromatography and gas chromatography-mass spectrometry analysis. Measurement of chlorophyll a content of Chlorella species cultivated on treated spent wash effluent obtained from immobilized fungal bioreactor was 5.16 +/- 0.71 mu g ml(-1) compared with 1.306 +/- 0.017 +/-mu g ml(-1) obtained with untreated spent wash. Thus, this work may provide a reasonable alternative for cost-effective bioremediation of distillery spent wash using immobilized A. oryzae on baggase fibers.
Show more [+] Less [-]An experimental study on eco-friendly and cost-effective natural materials for productivity enhancement of single slope solar still
2022
Natarajan, Sendhil Kumar | Suraparaju, Subbarama Kousik | Elavarasan, Rajvikram Madurai | Pugazhendhi, Rishi | Hossain, Eklas
The proposed research study aims to improve the productivity of solar still (SS) by using low-cost and eco-friendly materials. The aforementioned objective was achieved by enhancing the evaporation rate of seawater in the absorber basin and the condensation rate over the glass cover of the solar still. In this study, the low-cost and eco-friendly materials used for enhancing the evaporation rate in the solar still were molasses powder (MP), sawdust (SD) and rice husk (RH). In addition to these materials, bamboo straw (BS), banana leaf stem (BL) and rice straw (RS) were used as absorbing materials over the glass cover for enhancing the condensation rate. The experiments were carried out under similar meteorological conditions, and the results of the modified solar still were compared with the conventional solar still (CSS). The productivities of CSS, SSMP, SSRH, SSSD, SSBS, SSBL and SSRS were about 2250 mL/m², 2383 mL/m², 2467 mL/m², 3033 mL/m², 2700 mL/m², 2683 mL/m² and 3367 mL/m², respectively. The results of the experimental investigation highlighted that the SSSD had a comparatively better evaporation rate and 34.81% higher yield than CSS. Besides, SSRS had a comparatively better condensation rate and a 51.88% higher yield than CSS. Furthermore, the combination of sawdust (SD) and rice straw (RS) was investigated for the combined enhancement of evaporation and condensation. The solar still with sawdust and rice straw (SSSDRS) showed a 62.88% improvement in productivity with 3633 mL/m² when compared to CSS. Also, the economic analysis showed that the cost per litre (CPL) of freshwater obtained from SSSDRS was about ₹ 1.9 ($ 0.025) with a payback period of 4.4 months which was the least when compared to all the considered cases.
Show more [+] Less [-]Enhancement of Xanthan Biosynthesis Using Medicinal Herbs - A Novel Approach
2022
B. S. Rajyaguru, A. Varma, A. C. Kharkwal and J. Singh
This study aimed to evaluate the potential of five medicinal herbs in the enhancement of xanthan gum production when used against indigenously isolated (from molasses, an agricultural waste) phytopathogen Xanthomonas campestris MW741556. Antibiotic susceptibility of five medicinal herbs (Moringa oleifera, Bacopa monnieri, Glycyrrhiza glabra, Withania somnifera, and Arthrospira platensis) against X. campestris culture was first checked. All five herbs exhibited a clear zone of inhibition against X. campestris during the investigation. Thereafter their effect on enhancing the xanthan gum production was studied using molasses enriched medium. The results of this experiment showed that all five herbs were capable of enhancing xanthan gum production significantly. Xanthan gum produced differed in viscosity and dried biomass. Among all, A. platensis and M. oleifera were found to be the most promising for xanthan gum production with higher viscosity. These results were further confirmed by the characterization of xanthan gum produced by five herbs using Fourier Transform Infrared Spectroscopy. Further, a multivariate approach using principal component analysis confirmed the variability among the herbs used. This versatility of these medicinal herbs opens the possibility of their utilization and application in various fields.
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