Search Results (27)

Indonesia, particularly Central Java, generates substantial amounts of agricultural biomass residues, including melinjo shells, tobacco stalks, and cacao shells, which remain underutilized for energy applications. This study addresses the limited scientific evidence on the fuel properties and environmental performance of these residues by systematically evaluating their suitability as briquette feedstocks. A factorial experimental design was applied using three biomass types and two binders (tapioca starch and clay). The produced briquettes were characterized for moisture content, ash content, volatile matter, and higher heating value according to the Indonesian National Standard (SNI 01-6235-2000), and their environmental performance was assessed using a Life Cycle Assessment (LCA) approach to estimate associated environmental costs. The results indicate that briquettes made from melinjo shells with tapioca starch binder exhibited the most favorable performance, achieving a moisture content of 7.01%, ash content of 13.58%, volatile matter of 47.15%, and a calorific value of 5453.43 cal g⁻¹. However, the ash and volatile matter contents exceeded the recommended limits for solid biofuels. These findings demonstrate that melinjo shells are a promising feedstock for briquette production due to their relatively high energy content, while further improvements in carbonization conditions and reductions in binder proportion are required to enhance fuel quality and environmental performance. Full article

Microplastic pollution in farmland soils has emerged as a global concern due to its potential to degrade soil health, inhibit crop growth, and enter the food chain. However, effective and environmentally friendly remediation strategies remain limited, particularly regarding the use of biochar to mitigate polyethylene microplastic (PE-MP) stress in agroecosystems. This study investigates whether tobacco stalk biochar (TSB) can alleviate PE-MPs stress in rice seedlings. A two-factor pot experiment was conducted to systematically analyze the responses of soil physicochemical properties, rice growth indicators, and antioxidant enzyme activities to the combined application of varying concentrations of PE-MPs (0, 0.5%, 1%, and 2% (w/w)) and TSB (0, 3%, 6%, and 9% (w/w)). The results show that TSB significantly increased soil pH and organic matter content, effectively mitigating the decline in available nitrogen, phosphorus, and potassium caused by PE-MPs (e.g., under the M3B3 treatment, available nitrogen and phosphorus contents increased by 68.7% and 226%, respectively, compared with those under the M3B0 treatment). Under low-concentration PE-MP (0.5%) stress, an appropriate amount of TSB (3%) resulted in the highest rice germination rate, vigor index, and stress tolerance index, while significantly inducing the activities of superoxide dismutase (SOD) and catalase (CAT) to alleviate oxidative damage. However, high-concentration combinations of TSB and PE-MPs exhibited an antagonistic effect. In conclusion, tobacco stalk biochar can synergistically mitigate microplastic stress on rice through multiple pathways, with its remediation effects exhibiting significant dose dependence and interactive complexity. These findings provide a theoretical and technical basis for the ecological remediation of microplastic pollution in farmland. Full article

Tobacco (Nicotiana tabacum) cultivation generates millions of tons of stalk waste annually. This review explores the potential of tobacco stalks as a renewable resource, emphasizing sustainable applications within a circular economy framework, and highlights the key innovative advances. Composting and biochar production from tobacco residues can substantially enhance soil structure, nutrient availability, microbial activity, and heavy metal immobilization, supporting soil restoration and climate-smart agriculture. With 30–36% cellulose and moderate lignin contents, stalks can be converted into bioenergy, biogas, compost, and biopesticides and enable the production of cellulose derivatives. Despite promising results, challenges remain in nicotine detoxification, process optimization, and industrial scalability. Future research should focus on integrated technologies and life-cycle assessments to fully realize the environmental and economic benefits of tobacco waste valorization. Full article

The accumulation of microplastics in agricultural soils poses a serious threat to both crop production and ecosystem health. To explore potential remediation strategies, we conducted a two-factor pot experiment (PE-MPs × TSB). This study was designed to systematically analyze the interactive effects of polyethylene microplastics (PE-MPs) and tobacco stalk-derived biochar (TSB) on soil properties, physiological characteristics, and growth indicators of wheat. Results indicated that TSB addition significantly increased soil pH, organic matter, and available potassium content, which was associated with a mitigation of the soil acidification and nutrient imbalance observed under PE-MPs. Physiologically, TSB was linked to higher activities of antioxidant enzymes (SOD and POD) and maintained leaf chlorophyll content and photosynthetic function, thereby consistent with a reduction in oxidative stress and better maintenance of growth in the presence of PE-MPs. Furthermore, partial least squares structural equation modeling (PLS-SEM) supported a hypothetical cascading pathway for TSB’s dominant influence: soil improvement → physiological mitigation → growth recovery. The total effect of TSB on biomass (0.71) was substantially greater than that of PE-MPs (0.01). This study proposes a conceptual model and provides correlative evidence that is consistent with multi-level processes through which TSB may alleviate PE-MPs stress, thereby providing theoretical support for the resource utilization of agricultural waste and the green remediation of microplastic-contaminated soil. Full article

Straw returning is a critical practice with profound strategic importance for sustainable agricultural development. However, within a comprehensive soil health evaluation framework, research analyzing the impact of tobacco straw returning on soil ecosystem health from the perspectives of microbial taxa and functional genes remains insufficient. To investigate the effects of tobacco straw returning on virulence factor genes (VFGs), methane-cycling genes (MCGs), nitrogen-cycling genes (NCGs), carbohydrate-active enzyme genes (CAZyGs), antibiotic resistance genes (ARGs), and their host microorganisms in soil, this study collected soil samples from a long-term tobacco-rice rotation field with continuous tobacco straw incorporation in Shaowu City, Fujian Province. Metagenomic high-throughput sequencing was performed on the samples. The results demonstrated that long-term tobacco straw returning influenced the diversity of soil VFGs, MCGs, NCGs, CAZyGs, ARGs, and their host microorganisms, with richness significantly increasing compared to the CK treatment (p < 0.05). In the microbially mediated methane cycle, long-term tobacco straw returning resulted in a significant decrease in the abundance of the key methanogenesis gene mttB and the methanogenic archaeon Methanosarcina, along with a reduced mtaB/pmoA functional gene abundance ratio compared to CK. This suggests enhanced CH₄ oxidation in the tobacco-rice rotation field under straw returning. Notably, the abundance of plant pathogens increased significantly under tobacco straw returning. Furthermore, a significantly higher norB/nosZ functional gene abundance ratio was observed, indicating a reduced capacity of soil microorganisms to convert N₂O in the tobacco-rice rotation field under straw amendment. Based on the observation that the full-rate tobacco straw returning treatment (JT2) resulted in the lowest abundances of functional genes prkC, stkP, mttB, and the highest abundances of nirK, norB, malZ, and bglX, it can be concluded that shifts in soil physicochemical properties and energy substrates drove a transition in microbial metabolic strategies. This transition is characterized by a decreased pathogenic potential of soil bacteria, alongside an enhanced potential for microbial denitrification and cellulose degradation. Non-parametric analysis of matrix correlations revealed that soil organic carbon, dissolved organic carbon, alkaline-hydrolyzable nitrogen, available phosphorus, and available potassium were significantly correlated with the composition of soil functional groups (p < 0.05). In conclusion, long-term tobacco straw returning may increase the risk of soil-borne diseases in tobacco-rice rotation systems while potentially elevating N₂O and reducing CH₄ greenhouse gas emission rates. Analysis of functional gene abundance changes identified the full-rate tobacco straw returning treatment as the most effective among all treatments. Full article

As a special woody vegetable, Chinese toon (Toona sinensis) has a unique flavor, which is mainly formed by a combination of volatile substances. The secretion and storage of volatile odorants in plants are often carried out in trichomes. Currently, studies on the formation of T. sinensis flavor in terms of biosynthetic processes and epidermal trichome morphology are scarce. Here, we conducted a detailed analysis of the morphology, structure, and distribution of trichomes on the leaves of T. sinensis. We identified three types of trichomes: non-glandular, sessile glandular, and stalked glandular. We found that the distribution of trichomes varies greatly in the natural populations of T. sinensis, and this may be closely related to the changes in volatile components. In order to clarify the relationship between secondary metabolism and trichome formation, we integrated the metabolic analysis of volatiles with transcriptome analysis and discovered two important (Terpene Synthase) TPS genes that may be directly involved in terpene synthesis. Through the heterologous expression in tobacco and the transient expression in T. sinensis, we showed that the TPS genes can participate in the synthesis of sesquiterpenes, among which TsTPS1262 can lead to the synthesis of elemene in T. sinensis. Our study provides insights into the synthesis pathways of complex volatile components in T. sinensis and also provides a basis for flavor breeding applications. Full article

The growing demand for energy biomass encourages the use of waste and by-products from agriculture. The aim of this study was to assess the suitability of tobacco stalks (TSs) for energy use in the combustion and anaerobic digestion (AD) process, as well as the technical and environmental effects of energy production from this waste raw material. Laboratory tests were conducted on the energy parameters of TS biomass, the chemical composition of ash from its combustion, and the efficiency and composition of biogas generated during the AD process of TS silage with various silage additives. The tests were conducted in accordance with the standards applicable to biomass fuels. The energy yield and emission reduction obtained by the replacement of conventional energy sources were calculated. The energy parameters of TS were inferior compared to the raw materials most often burned in boilers (wood, straw). The high ash content (7.31% in dry mass) and its chemical composition may adversely affect heating devices. Methane yield from TS silage was lower (18.55–24.67 m³/Mg FM) than from silage from crops grown for biogas plants (i.e., 105 m³/Mg for maize silage). Silage additives improved TS silage quality and methane yield (from 18.55 to 21.71–24.67 m³ CH₄/Mg in case of silages with additives. Energy yield and emission reduction were higher in the case of TS combustion, but AD is a process consistent with the circular economy. Both TS energy management processes are in line with the Sustainable Development Goals as they prevent the devaluation of agricultural waste, providing a valuable resource for bioenergy. Full article

Sulfite-catalyzed acid pretreatment to overcome the inherent recalcitrance of biomass offers a significant advantage in terms of obtaining high glucose conversion. However, the residual lignin after enzymatic hydrolysis has not been fully exploited. Herein, this study introduced a joint approach using sulfite-catalyzed acid pretreatment (SPROL) and pyrolysis to upgrade tobacco stalk to produce fermentable sugar, and the resulting lignin is used to produce bio-oil and bio-char. The results suggest that SPROL pretreated tobacco stalk yields a high cellulose-based glucose selectivity of 75.9% with 15 FPU/g substrate enzyme dosage at 50 °C after 72 h of enzymolysis. Lignin characterization reveals that sulfonation occurred during SPROL pretreatment, and as the dosage of sulfonating agent increased, the thermal stability of the residue lignin decreased. After sample pyrolysis at 600 °C for 30 min, approximately 22%, 33%, and 45% of the lignin undergoes conversion into bio-oil, bio-char, and gas products, respectively. The bio-oil analysis results demonstrated that acetic acid is the most abundant identified GC-MS component at around 69.91% at the optimal condition, which implied that it could be of high value when utilized for pyroligneous acid. This research provides a synthetic approach using the SPORL technique to process tobacco stalk into fermentable sugar, bio-oil, and bio-char, which is significant for the commercial utilization of agricultural waste into value-added products. Full article

Background/Objectives: Bacterial wilt disease is a soil-borne disease caused by Ralstonia solanacearum that causes huge losses to crop economies worldwide. Methods: In this work, strain MLY102 was isolated and further identified as R. solanacearum from a diseased tobacco stalk. The genomic properties of MLY102 were explored by performing biochemical characterization, genome sequencing, compositional analysis, functional annotation and comparative genomic analysis. Results: MLY102 had a pinkish-red color in the center of the colony surrounded by a milky-white liquid with fluidity on TTC medium. The biochemical results revealed that MLY102 can utilize carbon sources, including D-glucose (dGLU), cane sugar (SAC) and D-trehalose dihydrate (dTRE). Genome sequencing through the DNBSEQ and PacBio platforms revealed a genome size of 5.72 Mb with a G+C content of 67.59%. The genome consists of a circular chromosome and a circular giant plasmid with 5283 protein-coding genes. A comparison of the genomes revealed that MLY102 is closely related to GMI1000 and CMR15 but has 498 special genes and 13 homologous genes in the species-specific gene family, indicating a high degree of genomic uniqueness. Conclusions: The unique characteristics and genomic data of MLY102 can provide important reference values for the prevention and control of bacterial wilt disease. Full article

Uncovering the structure of lignin from biorefinery has an important effect on lignin catalytic depolymerization and the production of bioenergy. In this study, two biorefinery lignins were isolated from tobacco stalks via alkaline and deep eutectic solvent (DES) catalyzed delignification processes, and the lignin heterogeneity structural characteristics were elucidated by gel permeation chromatography, 2D-HSQC, FT-IR, etc., to understand the relationship between the structure and the thermal characteristics of lignin. It was found that the lignins presented various structural characteristics and components, in which the predominant interunit linkages of black liquor lignin are β-O-4 and β-β linkages, and the β-O-4 linkages disappeared by DES treatment. DES lignins exhibited lower molecular weights and yields than black liquor lignin. Thermogravimetric analysis and fixed-bed pyrolysis were also performed to investigate the lignin thermal behavior. The results show that the DES approach can improve the bio-oil production from lignin and highlight the potential of DES lignin as a promising feedstock in the lignin pyrolysis process. This work provides a valuable example of the conversion of biorefinery lignin into pyrolysis products. Full article

Biochar, an eco-friendly, porous carbon-rich material, is widely studied for immobilizing heavy metals in contaminated environments. This study prepared tobacco stalks, a typical agricultural waste, into biochar (TSB) modified by hydroxyapatite (HAP) at co-pyrolysis temperatures of 350 °C and 550 °C to explore its Cd(II) adsorption behavior and relevant mechanisms. XRD, SEM–EDS, FTIR, and BET analyses revealed that HAP successfully incorporated onto TSB, enriching the surface oxygen-containing functional groups (P–O and carboxyl), and contributing to the enhancement of the specific surface area from 2.52 (TSB350) and 3.63 m²/g (TSB550) to 14.07 (HAP–TSB350) and 18.36 m²/g (HAP–TSB550). The kinetics of Cd(II) adsorption onto TSB and HAP–TSB is well described by the pseudo-second-order model. Isotherm results revealed that the maximum adsorption capacities of Cd(II) on HAP–TSB350 and HAP–TSB550 were approximately 13.17 and 14.50 mg/g, 2.67 and 9.24 times those of TSB350 and TSB550, respectively. The Cd(II) adsorption amounts on TSBs and HAP–TSBs increased significantly with increasing pH, especially in HAP–TSB550. Ionic strength effects and XPS analysis showed that Cd(II) adsorption onto HAP–TSBs occurred mainly via electrostatic interaction, cation exchange with Ca²⁺, complexation with P–O and –COOH, and surface precipitation. These findings will provide a modification strategy for the reutilization of tobacco agricultural waste in the remediation of heavy metal contaminated areas. Full article

Southwestern China is receiving excessive chemical fertilizers to meet the challenges of continuous cropping. These practices are deteriorating the soil environment and affecting tobacco (Nicotiana tabacum L.) yield and quality adversely. A novel microbially enriched biochar-based fertilizer was synthesized using effective microorganisms, tobacco stalk biochar and basal fertilizer. A field-scale study was conducted to evaluate the yield response of tobacco grown on degraded soil amended with our novel biochar-based microbial fertilizer (BF). Four treatments of BF (0%, 1.5%, 2.5% and 5%) were applied in the contaminated field to grow tobacco. The application of BF_1.5, BF_2.5 and BF_5.0 increased the available water contents by 9.47%, 1.18% and 2.19% compared to that with BF₀ respectively. Maximum growth of tobacco in terms of plant height and leaf area was recorded for BF_1.5 compared to BF₀. BF_1.5, BF_2.5 and BF_5.0 increased SPAD by 13.18–40.53%, net photosynthetic rate by 5.44–60.42%, stomatal conductance by 8.33–44.44%, instantaneous water use efficiency by 55.41–93.24% and intrinsic water use efficiency by 0.09–24.11%, while they decreased the intercellular CO₂ concentration and transpiration rate by 3.85–6.84% and 0.29–47.18% relative to BF₀, respectively (p < 0.05). The maximum increase in tobacco yield was recorded with BF_1.5 (23.81%) compared to that with BF₀. The present study concludes that the application of BF_1.5 improves and restores the degraded soil by improving the hydraulic conductivity and by increasing the tobacco yield. Full article

Nicotiana rustica L. (NRL) is a type of tobacco plant, and its stalk waste is a potential lignocellulosic source for obtaining cellulose fibers freely available in nature. However, they are left in fields after harvesting, and this study provides a green and sustainable method to reuse tobacco waste. Fiber was obtained by retting the plant stalks in water and decomposing them naturally in three weeks. NRL fiber was characterized by comparing it with known bast fibers, and tests were applied to examine its physical, chemical, mechanical, morphological, and thermal properties. With its high cellulose content (56.6 wt%), NRL fiber had a high tensile strength (113.4 MPa) and a good crystallinity index (70%) that helped it to bond with other fibers in the composite matrix. Furthermore, the fiber is an environmentally friendly alternative to synthetic fibers with a diameter of 36.88 μm and low density (1.5 g/cm³). The NRL fiber was found to have a semi-crystalline structure and large crystalline size, which makes it hydrophobic. The thermal gravimetric analysis showed that it can be durable (353.9 °C) in higher temperatures than the polymerization temperature. As a result, it can be concluded that NRL fiber has the potential to be used as a reinforcement in polymer composites, technical textiles, and agricultural applications. Full article

With the increasing concerns of human health and the ecological environment, tobacco stalks from the cigarette industry have been recognized as hazardous wastes requiring cautious treatment. However, there is still a lack of a simple and efficient route for full utilization of tobacco stalks. Herein, we attempted to convert tobacco stalk waste to value-added carbohydrates, bio-oil, and biochar through sequential hydrothermal and pyrolysis treatments. The results showed a high carbohydrate yield under the optimized condition using a microwave reaction system. The subsequent pyrolysis of residual solids at high temperatures could produce unexpected high-level aromatic chemicals including phenols and even benzenes—difficult to form without the facilitation of catalysts or salts. The obtained by-product biochar showed rapid absorption of tetracycline in 5 min and gradual introparticle diffusion from 30 to 240 min. The isotherm result had the characteristics of the Langmuir model, displaying homogeneous active sites on the biochar surface. Probably due to the hydrothermal pretreatment before pyrolysis, the obtained biochar exhibited a high adsorption capacity toward tetracycline without introducing the activation chemicals. These results illustrate that the proposed strategy may pave the way for dealing with tobacco wastes in the agricultural field. Full article

Waste biomass generated during agricultural production is a popular source of energy used in many developed and developing countries, due to economic factors and easy availability. Pellets produced from waste biomass generated during the cultivation of plants for industrial purposes are a good substitute for fossil fuels, the consumption of which should decrease for environmental reasons. This article presents the results of research on the use of waste biomass generated during the cultivation of plants for industrial purposes, such as sunflower, tobacco, and Jerusalem artichoke for the production of pellets. In addition, coniferous sawdust was used for the production of pellets. Mechanical, calorimetric, and thermogravimetric properties were tested. It was noted that pellets made of Jerusalem artichoke biomass (1591.45 N) were the most resistant to mechanical damage. The calorific value of the tested fuels ranged from 16.35 to 17.70 MJ·kg⁻¹, and the ash content was below 5%. In addition, during the combustion of pellets, the lowest emissions of nitrogen oxides were recorded for pellets made of tobacco stalks—45.56 mg·m⁻³ and sulfur dioxide for pellets consisting of a mixture of coniferous sawdust and tobacco stalks—1.88 mg·m⁻³. The addition of coniferous sawdust to each type of biomass tested resulted in a reduction in the emission of sulfur dioxide, carbon monoxide, and carbon dioxide, and an increase in the emission of nitrogen oxides. Based on the research, we found that the waste biomass generated during the cultivation of the tested plants for industrial purposes is a suitable raw material for the production of pellets used for industrial and non-industrial purposes. Full article