Vermicomposting of invasive weed Ageratum conyzoids: Assessment of nutrient mineralization, enzymatic activities, and microbial properties

Enhanced vermicomposting of rice straw and pressmud with biogas slurry employing Eisenia fetida: Production, characterization, growth, and toxicological risk assessment

The biogas plant plays a dual role: it directly provides energy and indirectly promotes organic farming through outlet slurry. However, agricultural biomass wastes such as rice straws (RS) and pressmud (PM), which can't be used as fertilizers on their own, were vermicomposted (60 days) with biogas slurry (BS), using earthworm, into four blends: T1(BS, 100%), T2(3:2, BS: RS), T3(3:2, BS: PM), and T4(3:1:1, BS: RS: PM). The characterization, elemental analysis, and toxicological risk assessment of derived vermimanure were carried out using various analytical tools, such as an organic elemental analyzer such as CHNS, FT-IR, FESEM-EDXA, XPS, and ICP-OES. The pH, electrical conductivity, and C/N values were within 7.1-7.8, 3.2-6.0 dSm-1, and 12-15, respectively, for all treatments. The proportions of N (38%), P (70%), K (58%), Mg (67%), Ca (42%), and ash (44%), increased significantly (P < 0.05) over the initial feedstocks. The ecological risks of heavy metals (Zn, Cu, Ni, Pb, Cd, and Cr) in all feedstocks were found to be under WHO-permitted levels. The growth performance of earthworms was also considerably higher (P < 0.05) over the control feedstock group. The analytical methods verified that feedstock T4 (3:1:1, BS: RS: PM) was more porous, containing NH4+, PO43-, K+, and other nutrients. Pellets of all vermimanure groups keep 65-75% of the original volume. As well, when these pellets have been employed for agronomy and dispersed in the field, they will cause less dust than traditional or powdered compost or manure. In comparison to the control group, the synergistic approach of RS, PM, and BS in vermimanure significantly (P < 0.05) enhanced seed germination (83%), vigour index (42.5%), and decreased mean germination time by 27%. Furthermore, pot trials with Abelmoschus esculentus seed indicated that seedlings cultivated with 40% vermimanure of T4 (3:1:1, BS: RS: PM) mixed soil showed high growth in shoot, root, and plant yield.

Vermicomposting technology - A perspective on vermicompost production technologies, limitations and prospects

The need for environmental sustainability while increasing the quantity, quality, and the rate of waste treatment to generate high-value environmental friendly fertilizer products is highly in demand. Vermicomposting is a good technology for the valorisation of industrial, domestic, municipal and agricultural wastes. Various vermicomposting technologies have been in use from time past to present. These technologies range from windrow, small - scale batch vermicomposting to large - scale continuous flow systems. Each of these processes has its own merits and demerits, necessitating advancement in the technology for efficient treatment of wastes. This work explores the hypothesis that the use of a continuous flow vermireactor system of a composite frame structure performs better than batch, windrow and other continuous systems operated in a single container. Following an in-depth review of the literature on vermicomposting technologies, treatment techniques, and reactor materials used, to explore the hypothesis, it was found that vermireactors operating in continuous flow fashion perform better in waste bioconversion than the batch and windrow techniques. Overall, the study concludes that batch techniques using plastic vermireactors predominate over the other reactor systems. However, the use of frame compartmentalized composite vermireactors performs considerably better in waste valorisation.

Vermistabilization of mango tree pruning waste with five earthworm species: A biochemical and heavy metal assessment

Mango tree pruning results in high biomass output, which is a serious agricultural and environmental problem. Vermicomposting is a potential, fast and sustainable tool to address these challenges. For sixty days, the experiment was carried out in six vermireactors containing five earthworm species by Eudrilus eugeniae, Eisenia fetida, Aporrectodea rosea, Lumbricus rubellus, and Lampito mauritii, as well as composting (without earthworm) using mango tree pruning waste biomass along with cattle dung as an instant preferred feeding material for earthworms. The pH, TOC, C/N and C/P ratios of the waste were substantially reduced by the earthworm activity. However, after vermicomposting, the levels of macronutrients (N, P, K, Ca, Mg, S) and micronutrients (Fe, Mn, Zn, and Cu) and microbial count substantially increased. The TOC content of waste was reduced by 42-55%, and the C/N of vermicompost ranged from 5.58 to 11.38. The results showed that earthworm fecundity was highest in vermireactors containing Eudrilus eugeniae and Eisenia fetida. The current study was ultimately determine that vermicomposting using Eudrilus eugeniae or Eisenia fetida is an effective strategy for utilising mango tree pruning waste, ensuring environmental sustainability and improving farmer revenue.

Insights into the panorama of antibiotic resistome in cropland soils amended with vermicompost in China

The accumulation and propagation of animal-derived antibiotic resistance genes (ARGs) pose great challenges to agricultural ecosystems. Vermicompost has drawn global attention as a new type of eco-friendly organic fertilizer. However, the effects of vermicompost application on ARGs in soil are still unclear. Here, we conducted a nationwide large-scale survey to explore the impact of vermicompost application on ARGs and the host in cropland fields as well as their regional differences. Vermicompost application was found to alter the pattern of ARGs, reduce the transfer of mobile genetic elements (MGEs), and mitigate the proliferation of high-risk bla-ARGs in soil. Regional differences in vermicompost-derived ARGs were observed in croplands, with less ARG-spreading risk in brown and yellow-brown soils. Total ARG abundance was present at the lowest level (1.24 × 10⁵-3.57 × 10⁷ copies/g) in vermicomposted soil compared with the croplands using animal manure (e.g., swine, chicken, and cow manure). Furthermore, vermicompost application increased the abundance of beneficial bacteria like Ilumatobacter and Gaiella, while reducing the abundance of Acidobacteria and Pseudarthrobacter. Network analysis showed that vermicompost altered ARG host bacteria and reduced the numbers of potential ARG hosts in soil. Microbes played a key role in ARG changes in vermicompost-treated soil. Our study provides valuable insight into the response of soil ARGs and the host to vermicompost in cropland ecosystem, and also provides a novel pathway for controlling the propagation of animal-derived ARGs.

Synergistic effect of biochar amendment in milk processing industry sludge and cattle dung during the vermiremediation

The effective and sustainable management of fast growing and large quantities of industrial waste is a serious issue. The purpose of the present study was to assess the synergistic effect of biochar (BC) amended in milk processing industry sludge (MS) mixed with cattle dung (CD) in different ratios through vermiremediation. The MS₂₅ and MS₂₅BC₁₀ (25:75 + 10 % BC) showed the least mortality and greatest earthworm growth and development. The final product from all feed mixtures recorded a decrease in pH, total organic carbon and C/N ratio. Other parameters viz., electrical conductivity, total available phosphorus, total Kjeldahl nitrogen, total sodium, total potassium and ash content was observed to be increased after vermicomposting. Significantly lower heavy metal content was found in all biochar amended feed mixtures than in mixtures without biochar. The germination index of Trigonella foenum-graecum showed a value ranging from 89.14 to 131.46 % for mixtures without BC and 115.18-153.47 % for biochar amended mixtures.

Decomposition and humification process of domestic biodegradable waste by black soldier fly (Hermetia illucens L.) larvae from the perspective of dissolved organic matter

Black soldier fly larvae (Hermitia illucens L.) (BSFL) bioconversion is a promising technology for domestic biodegradable waste (DBW) management and resource recovery. However, little is known about the DBW biodegradation during the BSFL bioconversion from the perspective of dissolved organic matter (DOM). In the current study, field tests were conducted on a full-scale BSFL bioconversion facility with treatment capacity of 15 tons DBW/day. Composition of DOM in DBW were investigated by spectral analysis (UV-vis, fluorescence, and Fourier Transform Infrared spectroscopy (FT-IR)), coupled with enzyme activity analysis. After BSFL bioconversion, DOM concentrations, total carbon and total nitrogen in residues decreased by 51.5%, 18.3% and 19.9%, respectively. Meanwhile, enzymes like catalase, lipase, protease, sucrase, urease and cellulase significantly increased (9.28%-56.3%). The specific UV absorbance at 254 nm and 280 nm (SUVA₂₅₄, SUVA₂₈₀), the area at 226-400 nm (A_226-400) and slope in the 280-400 nm region (S_280-400) of DOM increased by 230%, 186%, 143% and 398%, respectively. Moreover, the characteristic peaks at 1636, 1077 and 1045 cm^-1 in FT-IR increased continuously, with a significant decrease in peak at 1124 and 1572 cm^-1. DOM spectral data show that BSFL decomposed the carboxylic, cellulose and aliphatic components, resulting in the increase of oxygen-containing functional groups (e.g., hydroxyl, carboxyl, carbonyl) and aromatic compounds. Furthermore, fluorescence profiles show that Region Ⅰ, Ⅱ (aromatic proteins) and Ⅳ (soluble microbial byproducts) decreased while Region Ⅴ (humic-like substances) increased significantly. Humification index increased by 122% while biological index decreased by 18.0%, indicating a significant increase in degree of humification and stabilization of the residues. The current evidence provides a theoretical basis for technical re-innovation and improving economic potential of BSFL technology.

Bioconversion of fruit waste and sewage sludge mixtures by black soldier fly (Diptera: Stratiomyidae) larvae

Bioconversion of fruit waste (FW) and sewage sludge (SS) sludge mixtures into valuable products was investigated using black soldier fly (Hermetia illucens) larvae (BSFL) under a lab-scale trial. For that, five different setups of FW and SS mixtures (100FW; 100SS; 70SS+30FW; 50SS+50FW; 70FW+30SS) were prepared and changes in larval biomass, feed loss, and residual waste physicochemical properties were estimated until the emergence of fly in all waste mixtures. BSFL caused a significant decrease in total organic carbon (11.71-34.79%) and carbon-to-nitrogen ratio (C/N ratio) while the increase in total nitrogen (8.35-123.30%), total phosphorus (17.02-143.36%), and total potassium (19.40-48.87%) contents in the feedstock. The germination index and C/N ratio of frass were below the standards decided for manure quality in a few setups suggesting the non-stability of frass for agronomic applications due to the short duration (20 d) of composting. Larval biomass yield, feed conversion ratio and nutrient mineralization were found to be higher in 50SS+50FW and 70FW+30SS feedstock combinations suggesting their suitability as ideal feedstock for optimal BSFL cultivation. The impact of toxic substances in sewage on BSFL survival, growth and waste stabilization processes, and frass metal enrichment could be investigated in future studies.

The synergistic effect between biofertility properties and biological activities in vermicomposting: A comparable study of pig manure

Vermicomposting is a resource technology for managing animal excreta, whereas the internal relationships of the process are vital for its wide applications. The present study examined how macronutrient and micronutrient concentrations, microbial communities, and enzymatic activity of pig manure (PM) changed during the composting and vermicomposting processes and their internal interactions. The vermicomposting process increased macronutrients more significantly than composting (32.40% of total available nitrogen, 21.70% of total available phosphorous, and 12.70% of total available potassium). The vermicomposting reduced total organic carbon (7.91%), C/N ratio (61.35%), and humification index (56.47%) more than composting due to the quick decomposition of PM. After continual fertility optimization, the total microbial population, with the exception of total fungi, rose significantly to accelerate organics mineralization and improve macronutrients in vermicomposting compared to composting. Moreover, earthworm addition favored the stabilization of the PM containing higher concentrations of micronutrients after being catalyzed by the enhanced catalase activity and reduced sucrase activity after 90 days of vermicomposting. Principal component analysis and chord plots found that the generated vermicomposting products had higher fertility properties and biological activities induced by the synergistic effect of microorganisms and earthworms. These findings highlight vermicomposting is an eco-friendly management technology for processing PM and can be scaled up for agricultural applications.

Characterization of vermicompost of coconut husk mixed with cattle dung: physicochemical properties, SEM, and FT-IR analysis

The present work evaluated the potential of vermicomposting in management of different ratios of coconut husk waste (CH) and cattle dung (CD) viz (waste: CD) 0:100 (CH₀), 25:75 (CH₂₅), 50:50 (CH₅₀), 75:25 (CH₇₅), and 100:0 (CH₁₀₀) using Eisenia fetida for 120 days. The physicochemical properties were analyzed in vermicompost samples taken on the 0 and 120th day. Co-composting with cattle manure improved their acceptability for E. fetida as well as their physicochemical properties. In a 50:50 (CH₅₀) ratio, the lowest mortality and maximum growth in terms of number and biomass of earthworms were observed. The results revealed that during pre-vermicompost to post-vermicompost, nutrients such as nitrogen, phosphorus, and sodium increased, whereas in all vermicomposting end products organic carbon and the C:N ratio decreased significantly. Except zinc, all heavy metals decreased significantly (p < 0.05) over initial in all the feed mixtures. Seed germination tests indicated that the mature and non-phytotoxic vermicompost has been formed at the end of the experiment. The Fourier transmission infrared spectroscopy (FT-IR) and scanning electron microscopic (SEM) images of vermicompost demonstrated the excellent maturity of the compost.

Biochars modify the degradation pathways of dewatered sludge by regulating active microorganisms during gut digestion of earthworms

Biochar can accelerate the degradation and mineralization of organic matter during vermicomposting of sludge and the resulted vermicompost is termed as vermi-char containing active enzymes and microorganisms. However, the mechanisms by which biochars affect vermicomposting of the dewatered sludge during gut digestion of earthworms remain unclear. This study aimed to investigate the effects of biochar on the degradation pathways of organic matter and the involved active microorganisms in dewatered sludge during gut digestion of earthworms. The earthworms Eisenia fetida were fed on three sludge substrates; 1) sludge mixed with 5% corncob biochar, 2) sludge mixed 5% rice husk biochar, and 3) sludge without biochar. The results showed that dissolved organic carbon significantly decreased by 5.65%-21.81% after the 5-day gut digestion of earthworms (P < 0.05) and that biochar addition could accelerate the decomposition of aromatic protein-like substances. Contrarily, the nitrate in earthworms casting with biochars significantly increased by 47.32%-122.64% (P < 0.05) compared with the control. The numbers of active bacteria and eukaryotes in earthworm castings with biochars significantly enhanced by 1.34-1.45 times and 0.45-5.91 times, respectively, than the control (P < 0.05). Active Actinobacteria and Bacteroidetes dominated the castings with biochars significantly enriched by 76.18%-88.83% and 4.02%-18.59% (P < 0.05), respectively, compared to control. As for eukaryotes, the biochars amendment increased Cercozoa abundance by 114.23%-136.31% but decreased Annelida by 55.61%-75.88% in the castings. The partial least squares path model revealed that the biochars could change the content and structure of organic matter in earthworm castings during vermicomposting of sludge by affecting environmental factors, microbial abundance, and microbial community composition.

Deciphering waste bound nitrogen by employing psychrophillic Aporrectodea caliginosa and priming of coprolites by associated heterotrophic nitrifiers under high altitude Himalayas

Himalayan ecosystem is characterized by its fragile climate with rich repositories of biodiversity. Waste collection and disposal are becoming increasingly difficult due to topographical variations. Aporrectodea caligenosa, a versatile psychrophillic soil dweller, is a useful biocatalyst with potent bio-augmented capability for waste treatment at low temperatures. Microcosm experiments were conducted to elucidate the comprehensive nature of biogenic nitrogen transformation to NH₄⁺ and NO₃⁻ produced by coupling of earthworm-microbes. Higher biogenic recovery of NH₄⁺-N from coprolites of garden soil (47.73 ± 1.16%) and Himalayan goat manure (86.32 ± 0.92%) with an increment of 14.12 and 47.21% respectively over their respective control (without earthworms) with a linear decline beyond 4th week of incubation was reported. NO₃^–-N recovery progressively sustained in garden soil and goat manure coprolites during entire incubation with highest 81.81 ± 0.45 and 87.20 ± 1.08 µg-N g⁻¹dry weight recorded in 6th and 5th week of incubation respectively and peak increments as 38.58 and 53.71% relative to respective control (without earthworms). Declined NH₄⁺–N in coprolites at low temperature (15.0 ± 2.0 °C) evidenced increased nitrification rates by taking over the process by abundant nitrifying microbes. Steady de-nitrification with progressive incubation on an average was 16.95 ± 0.46 ng-N g⁻¹ per week and 21.08 ± 0.87 ng-N g⁻¹ per week compared to 14.03 ± 0.58 ng-N g⁻¹ per week and 4.50 ± 0.31 ng-N g⁻¹ per week in respective control treatments. Simultaneous heterotrophic nitrification and aerobic denitrification (SHNAD) was found to be a prominent bioprocess at low temperature that resulted in high and stable total nitrogen and nitrate accumulation from garden soil and goat manure with relative recovery efficiency of 11.12%, 14.97% and 14.20%; 19.34%. A. caligenosa shows promising prospects for mass applicability in biogenic N removal from manure of Himalayan goat.

Sustainable treatment and nutrient recovery from leafy waste through vermicomposting

The present investigation was carried out to evaluate the vermicomposting potential of two cruciferous vegetables' residual biomasses under laboratory conditions. Cabbage and cauliflower residual biomasses were spiked with 60% cow dung and vermicomposted for 90 days. The results showed a decrease in pH (5.3-9.8%), Total Organic Carbon (36.7-42.8%); increase in Electrical Conductivity (33-99.4%) and ash content (144.7-187.8%) after vermicomposting. Significant reduction in C:N ratio (49.5-76.4%) and C:P ratio (62.8-66.04%), increase in Total Kjeldahl Nitrogen (49.3-85.3%), Total Available Phosphorus (68.2-98.1%), Total Potassium (91.8-120.3%) were observed. FT-IR spectra of the vermicomposts had lesser band heights and peak intensities than raw materials. This evidenced decomposition of organic compounds and vermicompost stability. Germination Index values was calculated to determine the phytotoxicity level. Earthworms' growth and prolificacy was evaluated in terms of biomass gain, cocoons production and worm growth rate. Finally, it was inferred that cruciferous vegetables' biomass can be used for vermicomposting. The cauliflower residual biomass has shown better decomposition efficiency than cabbage residual biomass.

Eisenia fetida for vermiconversion of waste biomass of medicinal herbs: Status of nutrients and stability parameters

Vermiconversion possibility of waste biomass of two medicinal herbs Zingiber officinale and Curcuma longa has been investigated. The Eisenia fetida, an epigeic earthworm was used in the vermicomposting process. The vermicomposting caused shifting in pH towards neutral range, reduction in electrical conductivity, total organic carbon, C/N and C/P ratios whereas1.8-2.73 folds enhancement in macronutrients (TKN, AP, T Ca and T Mg) and ash contents in the substrate mixture. The heavy metals and trace elements content in the vermicompost were found within 3.25-1380 mg/kg and are under the permissible limits of compost applications. Besides, high germination index value in the vermicompost extract indicates loss of phytotoxicity and safe agricultural application potential of the end product. Finally, enhanced growth in Eisenia fetida confirms the application potential of harvested waste biomass as the raw materials for vermiconversion process.

Detoxification of coir pith through refined vermicomposting engaging Eudrilus eugeniae

Hazardous coir industrial waste, coir pith has been subjected to 50 days vermicomposting with Eudrilus eugeniae by amending nitrogenous legume plant, Gliricidia sepium together with cattle dung in different combinations, after 21 days precomposting using Pleurotus sajor-caju spawn. An increase in electrical conductivity, total NPK and calcium, and a decrease in organic matter, total organic carbon, C/N ratio, C/P ratio and total phenolic content in the final vermicompost were observed. Dehydrogenase, urease and cellulase activity peaked up to 30 days of vermicomposting and then declined. The phytotoxicity studies with Brassica juncea, C/N ratio and enzyme activities confirmed the stability and maturity of vermicompost. The results also demonstrated that the 2:3:1 ratio (coir pith + Gliricidia sepium + cow dung) is a suitable effective combination for nutrient-rich (N: 2.43%; P: 0.92%; K: 2.09%) vermicompost production. The total phenolic contents declined during the vermicomposting with a lower final content of 21.26 mg/g GAE in 2:3:1 combination of substrates from the initial level (105.56 mg/g GAE). Besides, the concentration of total phenol contents inversely related to the germination index of Brassica juncea (r = -0.761), indicating that the phenolic content could also play an important role in phytotoxicity. Growth and fecundity of Eudrilus eugeniae in 2:3:1 combination revealed the acceptability and rapid decomposition of coir pith substrate into vermifertilizer.

Fungal pretreatment facilitates the rapid and valuable composting of waste cardboard

This study investigates the waste cardboard (WCB) fungal pretreatment (Oligoporus placenta and Tremetes hirsuta) under monoculture and mixed culture and then composting for 35 d after mixing with cow dung in different ratios. Fungal pretreatment caused significant reduction in cellulose (28.3-35.8%), hemicellulose (61.4-68.4%), lignin (67.5-69.3%) content in WCB. Pretreated WCB showed better rates of decrement in total organic carbon (26.02-47.92%), carbon-to-nitrogen ratio (19.4-23.5), and lignocellulose contents, as well as incensement in total nitrogen (40.48-63.31%), total potassium (51.92-73.91%), germination index (88.5-102.0%), and elemental (Cu, Fe, Zn, Cr, and Mn) levels. Dehydrogenases (142-210 µg g^-1h^-1), and β-galactosidase (210-256 µg g^-1h^-1) activities indicates high microbial-mediated mineralization in setups. Results suggested that WCB could be used as a valuable substrate for valuable-added compost preparation after pretreating with a consortium of white-rot fungi.

Turning Waste into Beneficial Resource: Implication of Ageratum conyzoides L. in Sustainable Agriculture, Environment and Biopharma Sectors

The annual herb, Ageratum conyzoides L. (Asteraceae), is distributed throughout the world. Although invasive, it can be very useful as a source of essential oils, pharmaceuticals, biopesticides, and bioenergy. However, very limited information exists on the molecular basis of its different utility as previous investigations were mainly focused on phytochemical/biological activity profiling. Here we have explored various properties of A. conyzoides that may offer environmental, ecological, agricultural, and health benefits. As this aromatic plant harbors many important secondary metabolites that may have various implications, biotechnological interventions such as genomics, metabolomics and tissue-culture can be indispensable tools for their mass-production. Further, A. conyzoides acts as a natural reservoir of begomoviruses affecting a wide range of plant species. As the mechanisms of disease spreading and crop infection are not fully clear, whole-genome sequencing and various advanced molecular technologies including RNAi, CRISPER/Cas9, multi-omics approaches, etc., may aid to decipher the molecular mechanism of such disease development and thus, can be useful in crop protection. Overall, improved knowledge of A. conyzoides is not only essential for developing sustainable weed control strategy but can also offer potential ways for biomedicinal, environment, safe and clean agriculture applications.

Variations in bacterial taxonomic profiles and potential functions in response to the gut transit of earthworms (Eisenia fetida) feeding on cow manure

Earthworms play an important role in the organic matter decomposition in terrestrial ecosystems. Earthworms interact directly with the microorganisms to affect the organic matter decomposition via gut transit, i.e., the digestion and assimilation of organic matter in the foregut and midgut and its excretion by the hindgut. However, how the microbial community ingested by earthworms respond to the transit processes in different gut segments of earthworms is not clear. We used composted cow manure to feed earthworms and sampled vermicompost and the contents of foregut, midgut and hindgut for bacterial 16S rRNA gene sequencing analysis. We observed that earthworm gut transit decreased the abundances of the dominant phyla Proteobacteria and Bacteroidetes but increased Actinobacteria, Chloroflexi and Acidobacteria. The alpha diversity of bacterial community in midgut was the lowest of the different gut segments, and the bacterial community structure of the foregut was significantly different from the midgut and hindgut. The enrichment analysis results revealed different selective stimulatory and inhibitory effects on the ingested bacterial community in the different gut segments, which extended to vermicompost. The FAPROTAX data indicated that C and N metabolic microbes were enriched in the earthworm gut. Microbes involved in fermentation and methanogenesis were enriched in the hindgut, and denitrification microbes were enriched in the foregut. The N metabolism microbes in vermicompost were significantly enriched after the stimulation of earthworm gut transit (P < 0.05), and the pathogenic microbes of animals and plants were inhibited. Combined with the results of subsequent correlation and biochemical analyses, earthworm gut transit significantly altered the structure and function of the bacterial community to accelerate the degradation and mineralization of organic matter and the enrichment of phosphorus and potassium. Our study suggests that the gut transit process of earthworms plays an important role in regulating organic matter dynamics in terrestrial ecosystems.

Identification and quantitative chemical analysis of betaines in different organic wastes and their bioconversion composts

Global organic waste is increasing, bioconversion of organic waste arises because it can recover valuable nutrients and produce bioactive substances. Betaines are important bioactive substances in plants under environmental stress, but have received limited attention in vermicompost/larvae bioconversion compost. In this study, betaines in organic waste and vermicompost/larvae bioconversion compost were identified and quantified by HPLC-ESI-MS/MS. We observed the existence of glutamine betaine in all samples, which was first found in natural sources recently. Valine betaine was the highest among all detected betaines followed by GABA betaine, and both were rare in plants. The existence of tyrosine betaine in cow dung (CD) and vermicompost (CDV) was found, which was previously shown to be in fungi. Most importantly, we found larvae bioconversion could increase betaines by 5.56-99.75%, while vermicomposting decreased them. Bioconversion of larvae can effectively increase betaines in compost and can be used to produce potential novel functional organic fertilizers.

Metallothionein dependent-detoxification of heavy metals in the agricultural field soil of industrial area: Earthworm as field experimental model system

Earthworms are known to reclaim soil contamination and maintain soil health. In the present study, the concentration of DTPA extractable heavy metals, Cd, Cu, Cr, Pb, and Zn in vermicasts and tissues of the earthworms (anecic: Lampito mauritii; epigeic: Drawida sulcata) collected from the soils of four different industrial sites, Site-I (Sago industry), Site-II (Chemplast industry), Site-III (Dairy industry) and Site-IV (Dye industry) have been studied. The heavy metals in industrial soils recorded were 0.01-326.42 mg kg^-1 with higher Cu, Cr, and Zn contents while the vermicasts showed lower heavy metal loads with improved physicochemical properties and elevated humic substances. The higher humic substances dramatically decreased the heavy metals in the soil. The bioaccumulation factors of heavy metals (mg kg^-1) are in the order: Zn (54.50) > Cu (17.43) > Cr (4.54) > Pb (2.24) > Cd (2.12). The greatest amount of metallothionein protein (nmol g^-1) was recorded in earthworms from Site-IV (386.76) followed by Site-III (322.14), Site-II (245.82), and Site-I (232.21). Drawida sulcata can produce a considerable amount of metallothionein protein than Lampito mauritii as the metallothionein production is dependent upon the presence of pollutants. The molecular docking analysis indicates a binding score of 980 for Cd, Cr and Cu, and 372 for Zn. Pb may bind with a non-metallothionein protein of earthworms and bio-accumulated in the internal chloragogenous tissues. Metallothionein neutralizes the metal toxicity and controls the ingestion of essential elements.

Production of compost with biopesticide property from toxic weed Lantana: Quantification of alkaloids in compost and bacterial pathogen suppression

Toxic weed Lantana camara foliage was composted with cow dung in 2:1 and 1:1 ratio (v/v) and changes in physicochemical characteristics, and faecal coliform bacterial population (Escherichia coli and Salmonella) was estimated for 35 d. Results showed a significant increase in total N (1.48-1.69-folds), Paval (6.87-9.19-folds), and total K (1.08-1.23-folds) content, while a decrease in C/N ratio (1.87-2.13-folds) and total organic carbon (1.12-1.46-folds) after composting process. Germination index (GI) results (> 70 %) suggested the non-toxic property of Lantana compost against tested rapeseed mustard seeds. E. coli and Salmonella population reduced to the safe limit after 35 d composting. Compost extract (sterilized and non-sterilized) (from 2:1 setup) showed about 0.88 - 1.08-, 0.88 - 0.96-, 0.83 - 0.94-, and 0.79-1.08-folds higher inhibition in Xanthomonas citrus, Xanthomonas campestris, Erwinia carotovora, and Pseudomonas aerogenosa, respectively, indicating strong pathogen-inhibiting substances in Lantanacompost. GC-MS analysis of compost extract indicated the presence of isomers of several compounds of biocidal property - hexadecane (9-hexyl and 9-octyl); 2-tridecyl ester; eicosane; tetradecane, heptacosane (1-chloro- and 9-hexyl); heptadecane, octadecane, 3-ethyl-5-(2-ethylbutyl)-, heptacosane, tetradecane, 2,6,10-trimethyl-, etc.). Result revealed that Lantana compost could be used as biomanure with biopesticide properties for sustainable organic farming system.

Centrality of cattle solid wastes in vermicomposting technology - A cleaner resource recovery and biowaste recycling option for agricultural and environmental sustainability

The current review reports the importance and significance of cattle solid waste in vermicomposting technology concerning biowaste pollution in the environment. Needy increasing population evokes livestock production resulting in the massive generation of livestock wastes, especially cattle dung. Improper disposal and handling of biowastes originating from agriculture, industries, forests, rural and urban areas lead to nutrient loss, environmental pollution and health risks. Among the organic waste disposal methods available, vermicomposting is regarded as an environmentally friendly technology for bioconversion of agricultural, industrial, rural and urban generated organic solid wastes which are serving as reservoirs of environmental pollution. In vermicomposting of organic wastes, cattle dung plays a central role in mineralization, nutrient recovery, earthworm and microbial activity leading to vermifertilizer production. Even though the vermicomposting studies use cattle dung invariably as an amendment material, its importance has not been reviewed to highlight its central role. Hence, the present review mainly emphasizes the key role played by cattle dung in vermicomposting. Vermiconversion of cattle dung alone and in combination with other biowaste materials of environmental concern, mechanisms involved and benefits of vermicompost in sustainable agriculture are the major objectives addressed in the present review. The analysis reveals that cattle dung is indispensable amendment material for vermicomposting technology to ensure agricultural and environmental sustainability by reducing pollution risks associated with biowastes on one hand, and nutrient-rich benign vermifertilizer production on the other hand.