Lignocellulolytic Bacteria Research Articles

Extracytoplasmic polysaccharides control cellulosomal and non-cellulosomal systems in Herbivorax saccincola A7

Herbivorax saccincola A7 is an anaerobic alkali-thermophilic lignocellulolytic bacterium that possesses a cellulosome and high xylan degradation ability. To understand the expression profile of extracellular enzymes by carbon sources, quantitative real-time PCR was performed on all cellulosomal and non-cellulosomal enzyme genes of H. saccincola A7 using cellulose and xylan as carbon sources. The results confirmed that the scaffolding proteins of H. saccincola A7 were expressed. In general, the cellulosomal genes belonging to the glycoside hydrolase families 9, 10, 11, and 48 were repressed when xylan was the sole carbon source, but these genes were significantly induced in the presence of cellulose. These results indicate that cellulose, not xylan, is a key inducer of cellulosomal genes in H. saccincola A7. The RsgI-like proteins, which regulate a carbohydrate-sensing mechanism in Clostridium thermocellum, were also found to be encoded in the H. saccincola A7 genome. To confirm the regulation by RsgI-like proteins, the relative expression of σI1–σI4 factors was analyzed on both carbon sources. The expression of alternative σI1 and σI2 factors was enhanced by the presence of cellulose. By contrast, the expression of σI3 and σI4 factors was activated by both cellulose and xylan. Taken together, the results reveal that the cellulosomal and non-cellulosomal genes of H. saccincola A7 are regulated through a carbohydrate-sensing mechanism involving anti-σ regulator RsgI-like proteins.Key points• qRT-PCR performed on cellulosomal and non-cellulosomal genes of H. saccincola A7• Cellulose is a key inducer of the cellulosome of H. saccincola A7• H. saccincola A7 possesses a similar system of anti-σ regulator RsgI-like proteins

Optimizing Nitrogen Fertilization for Enhanced Rice Straw Degradation and Oilseed Rape Yield in Challenging Winter Conditions: Insights from Southwest China

The crop straw returning to the field is a widely accepted method to utilize and remediate huge agricultural waste in a short period. However, the low temperatures and dry conditions of the winter season in Southwest China can be challenging for the biodegradation of crop straw in the field. With a similar aim, we designed a short-term study where rice straw was applied to the field with different concentrations of nitrogen (N) fertilizer while keeping phosphorus (P) constant; CK, (N0P0); T1, (N0P90); T2, (N60P90); T3, (N120P90); and T4, (N180P90) were added to evaluate its impact on straw degradation during cold weather. We found that high fertilization (T4) significantly improved crop yield, organic matter, and lignocellulose degradation under cold temperatures (21.5–3.2 °C). It also significantly improved soil nitrogen agronomic efficiency, nitrogen use efficiency, and nitrogen physiological efficiency. The yield was highest in T4 (1690 and 1399 kg/ha), while T3 acted positively on soil lignocellulolytic enzyme activity, which in turn resulted in higher degradation of OM and lignocellulosic material. Pearson’s correlation analysis revealed that total nitrogen, total phosphorus, available nitrogen, and available phosphorus were important variables that had a significant impact on soil EC, bulk density, water holding capacity, and soil enzymes. We found that nitrogen application significantly changed the soil bacterial community by increasing the richness and evenness of lignocellulolytic bacteria, which aided the degradation of straw in a short duration. This study’s finding indicates that the decomposition of crop straw in the field under cold weather stress was dependent on nutrient input, and N, in an appropriate amount (N120-180), was suitable to achieve higher yield and higher decomposition of straw in such an environment.

Enhanced gut microbiome supplementation of essential amino acids in Diploptera punctata fed low-protein plant-based diet.

Building on our previous work, we investigate how dietary shifts affect gut microbial essential amino acid (EAA) provisioning in the lactating cockroach Diploptera punctata. To that end, we fed cockroaches three distinct diets: a plant-only Gari diet composed of starchy and granulated root tuber Yucca (Manihot esculenta), a dog food diet (DF), and a cellulose-amended dog food (CADF) diet. We anticipated that the high carbohydrate, low protein Gari would highlight increased microbial EAA supplementation to the host. By day 28, we observed distinct profiles of 14 bacterial families in the insect gut microbiomes of the three dietary groups. CADF-fed insects predominantly harbored cellulolytic and nitrogen-fixing bacteria families Streptococcaceae and Xanthomonadaceae. In contrast, Gari-fed insects were enriched in anaerobic lignocellulolytic bacteria families Paludibacteraceae andDysgonomonadaceae, while DF-fed insects had a prevalence of proteolyticanaerobes Williamwhitmaniaceae and sulfate-reducing bacteria Desulfovibrionaceae. Furthermore, we confirmed significantly higher EAA supplementation in Gari-fed insects than in non-Gari-fed insects based on δ13C-EAA offsets between insect and their diets. The δ13C-EAA offsets between DF and CADF were nearly indistinguishable, highlighting the relevance of using the plant-based Gari in this experiment to unequivocally demonstrate this function in this insect. These results were underscored by lower standard metabolic rate (SMR) relative to the DF insect in Gari-fed (intermediate SMR and dietary quality) and CADF (least SMR and dietary quality) insects. The influence of diet on EAA provisioning and SMR responses in insects underscores the need for further exploration into the role of gut microbial functions in modulating metabolic responses.

Grasshopper (Oxya chinensis) Gut Bacteria and their Cellulolytic Activity

Lignocellulose is a core component of plant biomass and the most abundant carbohydrate polymer in nature. It is cheap and renewable and has several potential applications; however, it remains underutilized because of its recalcitrance to degradation. Cellulolytic microbes have been found in the gut of herbivorous insects, such as grasshoppers. This study aimed to isolate lignocellulolytic bacteria from the gut of grasshoppers (Oxya chinensis) and determine their diversity and potential biomass-degrading activity. A total of 27 culturable isolates were obtained from the grasshopper foregut, midgut, and hindgut. The bacteria hydrolyzed cellulose and lignin, as indicated by a cellulolytic index of 0.12–1.23 and ligninolytic index of 0.1–1.47. Five potential cellulolytic bacterial isolates were selected. Based on 16S rRNA sequencing, the isolates were identified as Bacillus wiedmannii (foregut), Bacillus marcorestinctum, Bacillus halotolerans (midgut), Paenibacillus zanthoxyli, and Bacillus hominis (hindgut). The highest specific cellulolytic activity (0.0068 U/mg) was detected in B. wiedmannii (OCF2), which could be exploited as a potential source of cellulases.

Enhanced bioconversion of grass straw into bioethanol by a novel consortium of lignocellulolytic bacteria aided by combined alkaline-acid pretreatment

Enhanced bioconversion of grass straw into bioethanol by a novel consortium of lignocellulolytic bacteria aided by combined alkaline-acid pretreatment

Isolation of Lignocellulolytic Bacteria From Erek-erek Geoforest Ijen Geopark, Indonesia

Ijen Geopark is one of the UNESCO Global Geoparks in Indonesia. The Erek-erek Geoforest (EEG) is one of the biosites in the Ijen Geopark. The EEG has an abundant biomass which is composed of lignocellulosic complex. The abundance of biomass has the potential as a source of lignocellulolytic microorganisms that can degrade lignocellulose material. The purpose of this research was to isolate lignocellulolytic bacteria from the Erek-erek Geoforest. This research method was soil sampling, physicochemical analysis of soil, isolation, and purification of bacteria, growth capability in lignocellulose media, and pathogenicity-test. The results showed that a total of 180 were isolated from EEG. There are 93 bacteria growth in lignin media and 142 bacteria growth in cellulolytic with the isolated code EIB (erek-erek Ijen Banyuwangi) under aerobic conditions which had various bacterial morphologies. To ensure the safety of using these isolates, it is necessary to do a pathogenicity test of these bacteria using a blood agar plate. Indicated pathogenic bacteria will form a clear zone around the bacterial colony on the blood media. The pathogenicity test of the highest lignocellulolytic bacteria showed that the 3 ligninolytic and 3 cellulolytic EIB bacteria isolates were non-pathogenic. Further, non-pathogenic bacteria from the soil litter of erek-erek forests can be tested for their potential as biological agents for the industry.

Factors regulating lignocellulolytic microbes, their degrading enzymes, and heterotrophic respiration in oil palm cultivated peatlands

Even though their role in mediating tropical peat decomposition and GHG emissions had been widely recognized, information concerning lignocellulolytic microbes, their degrading enzyme ability, and interconnection with soil physicochemical properties and peat heterotrophic respiration on mature oil palm plantation/OPP block level were rudimentary. This study evaluated the effect of sampling depth (0-30, 30-60, and 60-90 cm), OPP management zone (fertilization circle/FTC, frond stack/FRS, and harvesting path/HVP), and peat physicochemical properties on the lignocellulolytic bacteria and fungi, their degrading enzymes activities and peat heterotrophic respiration/Rh using principal component analysis/PCA, multiple linear regression/MLR, and generalized linear mixed effect models/GLMM. This study found that the soil microbiological and physicochemical properties varied widely. Dominant lignocellulolytic bacterial population and their cellulase enzyme activity were higher than fungi, regardless of sampling depth and management zone. PCA and GLMM analyses showed the significant importance of sampling depth and management zone in governing lignocellulolytic microbial population, their enzyme activities, and Rh. Microbial population and cellulase activity were also remarkably affected by the interaction of all studied factors. Peat chemical properties (pH and total Mn) controlled the natural variance of lignocellulolytic microbes and their enzymes, whereas total K regulate Rh. This study suggested that the research on microbiological-related GHG mitigation in OPP should be focused on managing the fungal population and cellulase enzyme activity at the peat surface (0-30 cm) and fertilization circle.

Key roles of β-glucosidase BglA for the catabolism of both laminaribiose and cellobiose in the lignocellulolytic bacterium Clostridium thermocellum

The thermophilic bacterium Clostridium thermocellum efficiently degrades polysaccharides into oligosaccharides. The metabolism of β-1,4-linked cello-oligosaccharides is initiated by three enzymes, i.e., the cellodextrin phosphorylase (Cdp), the cellobiose phosphorylase (Cbp), and the β-glucosidase A (BglA), in C. thermocellum. In comparison, how the oligosaccharides containing other kinds of linkage are utilized is rarely understood. In this study, we found that BglA could hydrolyze the β-1,3-disaccharide laminaribiose with much higher activity than that against the β-1,4-disaccharide cellobiose. The structural basis of the substrate specificity was analyzed by crystal structure determination and molecular docking. Genetic deletions of BglA and Cbp, respectively, and enzymatic analysis of cell extracts demonstrated that BglA is the key enzyme responsible for laminaribiose metabolism. Furthermore, the deletion of BglA can suppress the expression of Cbp and the deletion of Cbp can up-regulate the expression of BglA, indicating that BglA and Cbp have cross-regulation and BglA is also critical for cellobiose metabolism. These insights pave the way for both a fundamental understanding of metabolism and regulation in C. thermocellum and emphasize the importance of the degradation and utilization of polysaccharides containing β-1,3-linked glycosidic bonds in lignocellulose biorefinery.

Isolation of lignocellulolytic bacteria from oil palm mesocarp waste

In the present investigation, the bacterial strains were isolated from oil palm mesocarp waste dumped soil by serial dilution and pour plate method. The highest lignocellulolytic index was produced by bacterial isolate OPMW 6 (1.5 mm) followed by OPMW 5 (1.2 mm), OPMW 1 (0.83 mm), OPMW3 and OPMW 4 (0.71 mm). Changes in methylene blue color supplemented in nutrient broth from blue to light green or yellow were observed by three bacterial isolates (OPMW1, OPMW 3 and OPMW5), and rest of the bacterial isolatesrecorded less decolourization as the cultures were incubated between 24 and 48 hours respectively with highest percentage of dye decolourization produced by bacterial isolate i.e. OPMW5 (83.3%) and lowest rate ofdecolourization by bacterial isolate OPMW 6 (13.54%) as inoculated in nutrient broth supplemented with methylene blue dye. Utilization of gallic acid as supplemented in minimal salt media recorded positive reactionfor 4 bacterial isolates (OPMW 2, OPMW 5, OPMW 6 and OPMW 8) by the formation of dark colouration and addition ofa-naphthol in MSM inoculated broth culturesshowed formation of purple blue colour due to productionof laccase activity. Among the 4 best isolates having the highest indices, two isolates of bacteria (OPMW5 and OPMW6) had the best lignocellulolytic activity. Based on enzyme biosynthesis ability, the OPMW5 and OPMW6were selected as the best isolates as it can synthesie cellulase and ligninase enzymes. These enzymes are known to accelerate the degradation of oil palm mesocarp fibre substrate.

Proficient Lignocellulolytic Novel Bacterial Isolates from Diversified Galiyat Forests of Lower Himalaya

Lignocellulosic biomass needs attention as an alternative energy source to overcome the adverse impacts of fossil fuels. Diversified Galiyat forests of Lower Himalaya may represent the potential source of lignocellulose degrading microbiota, particularly the lytic bacteria. Therefore, soil and wood samples were collected from different sites of Nathiagali and Thandiani of Galiyat forests. The soil samples collected were clayey, with a pH between 6.7 and 7.0, and with an organic matter of 2.8%–2.9% in Nathiagali and 2.1%–2.2% in Thandiani. The soils were enriched with more diversified cultivable bacteria (9 Log CFU/g) than the respective wood samples (7.4–8.6 Log CFU/g). Out of 90 bacteria, 22 isolates were efficient for cellulose degradation, 14 for xylanase activity, and 10 for laccase production. Cluster analysis showed that lignocellulolytic bacteria were grouped based on the sample medium (soil–wood) rather than the sampling site (Thandiani–Nathiagali). Efficient bacteria were also sequenced, and we found that cellulase production was prevalent in Pseudomonas spp. while laccase activity was diverse among taxonomically varied bacteria. Moreover, Stenotrophomonas sp. TS2B1 performed the best for corncob xylose degradation. Overall, the results suggest that Galiyat forests represent diverse lignocellulolytic microbial populations which should be further evaluated for applications in lignocellulosic waste management and for potential consequent fuel production.

Isolation and Characterization of Lignocellulolytic Bacteria from Municipal Solid Waste Landfill for Identification of Potential Hydrolytic Enzyme

The utilization of lignocellulose biomass as an alternative source of renewable energy production via green technology is becoming important, and is in line with sustainable development goal initiatives. Lignocellulolytic bacteria, such as Bacillus spp., can break down biomass by producing hydrolytic enzymes, which are crucial in the successful conversion of biomass or lignocellulosic material into renewable energy. This information gave rise to this study, where municipal solid waste sediments of a sanitary municipal solid waste landfill were sampled and screened, and lignocellulolytic bacteria were isolated and characterized. Samples were taken from four different locations at the Pulau Burung landfill site in Malaysia. Lignin and starch were used as sources of carbon to identify potential bacteria that exhibit multi-enzymatic activity. The growth rate and doubling time of bacterial isolates in lignin and starch were taken as the criteria for selection. Eleven bacterial isolates were screened for cellulase activity using iodine and Congo red dyes. The cellulase activity of these isolates ranged from 0.8 to 1.7 U/mL. We carried out 16S rRNA gene sequencing to identify the phyla of the selected bacterial isolates. Phylogenetic analysis was also conducted based on the 16S rRNA sequences of the bacterial isolates and related Bacillus species, and a tree was generated using the Neighbor-Joining method. In this study, Bacillus proteolyticus, Bacillus Sanguinis, Bacillus spizizenii, Bacillus paramycoides, Bacillus paranthracis and Neobacillus fumarioli were identified as promising bacteria capable of expressing lignocellulolytic enzymes and degrading the lignocellulosic biomass present in municipal solid waste.

Taxonomic and enzymatic basis of the cellulolytic microbial consortium KKU-MC1 and its application in enhancing biomethane production

Lignocellulosic biomass is a promising substrate for biogas production. However, its recalcitrant structure limits conversion efficiency. This study aims to design a microbial consortium (MC) capable of producing the cellulolytic enzyme and exploring the taxonomic and genetic aspects of lignocellulose degradation. A diverse range of lignocellulolytic bacteria and degrading enzymes from various habitats were enriched for a known KKU-MC1. The KKU-MC1 was found to be abundant in Bacteroidetes (51%), Proteobacteria (29%), Firmicutes (10%), and other phyla (8% unknown, 0.4% unclassified, 0.6% archaea, and the remaining 1% other bacteria with low predominance). Carbohydrate-active enzyme (CAZyme) annotation revealed that the genera Bacteroides,Ruminiclostridium,Enterococcus, and Parabacteroides encoded a diverse set of cellulose and hemicellulose degradation enzymes. Furthermore, the gene families associated with lignin deconstruction were more abundant in the Pseudomonas genera. Subsequently, the effects of MC on methane production from various biomasses were studied in two ways: bioaugmentation and pre-hydrolysis. Methane yield (MY) of pre-hydrolysis cassava bagasse (CB), Napier grass (NG), and sugarcane bagasse (SB) with KKU-MC1 for 5 days improved by 38–56% compared to non-prehydrolysis substrates, while MY of prehydrolysed filter cake (FC) for 15 days improved by 56% compared to raw FC. The MY of CB, NG, and SB (at 4% initial volatile solid concentration (IVC)) with KKU-MC1 augmentation improved by 29–42% compared to the non-augmentation treatment. FC (1% IVC) had 17% higher MY than the non-augmentation treatment. These findings demonstrated that KKU-MC1 released the cellulolytic enzyme capable of decomposing various lignocellulosic biomasses, resulting in increased biogas production.

Characterization of Potential Virulence, Resistance to Antibiotics and Heavy Metals, and Biofilm-Forming Capabilities of Soil Lignocellulolytic Bacteria

Soil bacteria participate in self-immobilization processes for survival, persistence, and production of virulence factors in some niches or hosts through their capacities for autoaggregation, cell surface hydrophobicity, biofilm formation, and antibiotic and heavy metal resistance. This study investigated potential virulence, antibiotic and heavy metal resistance, solvent adhesion, and biofilm-forming capabilities of six cellulolytic bacteria isolated from soil samples: Paenarthrobacter sp. MKAL1, Hymenobacter sp. MKAL2, Mycobacterium sp. MKAL3, Stenotrophomonas sp. MKAL4, Chryseobacterium sp. MKAL5, and Bacillus sp. MKAL6. Strains were subjected to phenotypic methods, including heavy metal and antibiotic susceptibility and virulence factors (protease, lipase, capsule production, autoaggregation, hydrophobicity, and biofilm formation). The effect of ciprofloxacin was also investigated on bacterial susceptibility over time, cell membrane, and biofilm formation. Strains MKAL2, MKAL5, and MKAL6 exhibited protease and lipase activities, while only MKAL6 produced capsules. All strains were capable of aggregating, forming biofilm, and adhering to solvents. Strains tolerated high amounts of chromium, lead, zinc, nickel, and manganese and were resistant to lincomycin. Ciprofloxacin exhibited bactericidal activity against these strains. Although the phenotypic evaluation of virulence factors of bacteria can indicate their pathogenic nature, an in-depth genetic study of virulence, antibiotic and heavy metal resistance genes is required.

The effect of lignocellulolytic bacteria consortium on composting empty oil palm fruit bunches

Oil palm empty fruit bunches (OPEFB) are waste produced by palm oil mills from processing fresh fruit bunches into oil. For every 1 tonne of fresh fruit bunch (FFB) processing, 21–23% EFB will be produced. EFB can be used as compost. OPEFB compost has considerable potential because it contains complex nutrients (macro and micro). The OPEFB composting process has problems because of the lignin content which causes the decomposition process to take a long time so that microorganisms are needed that can accelerate the OPEFB decomposition rate. This study aimed to test the ability of lignolytic bacteria from larvae of Oryctes rhinoceros L. plus cellulolytic bacteria from organic waste that have the potential to decompose OPEFB. This research was conducted experimentally using a non-factorial Completely Randomized Design (CRD) consisting of eight treatments. The results showed that the administration of cellulolytic bacterial isolates had a significant effect on water content, compost weight loss, pH, C-Organic, C/N ratio and P nutrient content, but had no significant effect on N and K nutrient levels. Treatment of lignocellulolytic bacteria ORL9 and ORL6 and a consortium of cellulolytic bacteria showed good compost quality, which could be seen from the parameters of weight loss of compost, pH, N nutrient content and reduced C/N ratio.

Optimization of lignocellulolytic bacterial inoculum and substrate mix for lignocellulose degradation and product quality on co-composting of green waste with food waste

The present study evaluates the effect of the mixing ratio of substrates and inoculation with lignocellulolytic bacteria on green waste (GW) and food waste (FW) co-composting. A Box-Behnken design was used to simultaneously optimize the lignocellulose degradation (%LD) and end-product quality. The best operational conditions were 4.85*105 CFU g−1 of Bacillus sp. F3X3 and 1.44*106 CFU g−1 of Paenibacillus sp. F1A5 with a substrate mixture containing 50% GW, 32.5% unprocessed FW, 2.5% processed FW, 13% sawdust, and 2% phosphate rock; with a C/N ratio of 27. Under these conditions, the %LD was 33% and the end-product has pH 8.3, TOC 22,4%, TN 1,7%, and a germination index of 103%. Therefore, the product complies with quality standards for organic fertilizers. The results of this study allow the identification of appropriate strategies to optimize GW composting, increasing the degradation of lignocellulose and improving the end-product quality.

Exploring the region-wise diversity and functions of symbiotic bacteria in the gut system of wood-feeding termite, Coptotermes formosanus, toward the degradation of cellulose, hemicellulose, and organic dyes.

The wood-feeding termite Coptotermes formosanus represents a unique and impressive system for lignocellulose degradation. The highly efficient digestion of lignocellulose is achieved through symbiosis with gut symbionts like bacteria. Despite extensive research during the last three decades, diversity of bacterial symbionts residing in individual gut regions of the termite and their associated functions is still lacking. To this end, cellulose, xylan, and dye-decolorization bacteria residing in foregut, midgut, and hindgut regions of C. formosanus were enlisted by using enrichment and culture-dependent molecular methods. A total of 87 bacterial strains were successfully isolated from different gut regions of C. formosanus which belonged to 27 different species of 10 genera, majorly affiliated with Proteobacteria (80%) and Firmicutes (18.3%). Among the gut regions, 37.9% of the total bacterial isolates were observed in the hindgut that demonstrated predominance of cellulolytic bacteria (47.6%). The majority of the xylanolytic and dye-decolorization bacteria (50%) were obtained from the foregut and midgut, respectively. Actinobacteria represented by Dietza sp. was observed in the hindgut only. Based on species richness, the highest diversity was observed in midgut and hindgut regions each of which harbored seven unique bacterial species. The members of Enterobacter, Klebsiella, and Pseudomonas were common among the gut regions. The lignocellulolytic activities of the selected potential bacteria signpost their assistance to the host for lignocellulose digestion. The overall results indicate that C. formosanus harbors diverse communities of lignocellulolytic bacteria in different regions of the gut system. These observations will significantly advance our understanding of the termite-bacteria symbiosis and their microbial ecology uniquely existed in different gut regions of C. formosanus, which may further shed a light on its potential values at termite-modeled biotechnology.

Cellulose degrading bacteria isolated from Palangkaraya, Central Kalimantan, Indonesia as peat fiber decomposer to accelerate peat soil compression

Abstract. Zulaika E, Solikhah F, Utomo MAP, Endah N, Assavalapsakul W. 2022. Cellulose degrading bacteria isolated from Palangkaraya, Central Kalimantan, Indonesia as peat fiber decomposer to accelerate peat soil compression. Biodiversitas 23: 1648-1654. Peat soil was established from incomplete weathered plants. It delays the process of soil compression. The main components of peat soil are fibers which made of cellulose and lignin that can be enzymatically degraded by cellulolignolytic bacteria. The objective of this study was to isolate indigenous lignocellulolytic bacteria from peat soil that perform peat fiber degradation to accelerate soil compression process. A bacteria screening test was carried out on carboxymethyl cellulose (CMC) media and bacteria identification using 16S rRNA gene markers. Peat fiber decomposition test based on biomass loss, decomposition results were visualized using scanning electron microscopy (SEM) and analyzed using Fourier Transform Infrared (FTIR). The results of screening and identification obtained 5 bacterial species, namely Pseudomonas taiwanensis U3 and Bacillus cereus D1, D3, U2, U4. After six weeks of incubation, P. taiwanensis U3 showed the highest cellulase activity than other isolates with 90% decomposition ability of peat fibers. The results of the decomposition of peat fibers with the addition of isolates visualized smaller pore sizes than control. Stretching occurs in the aromatic group of the C-O ester bond, the CºC structure of the alkyne group, and the O-H of the alcohol. All obtained bacteria isolates were still viable after six weeks of incubation with 104 CFU g-1 dry weight of fiber. The present investigation deals with isolating indigenous lignocellulolytic bacteria from peat soil that perform peat fiber degradation to accelerate the soil compression process. Our findings are also the first publication that reported P. taiwanensis cellulolytic potential.

Effectivity of Biocatalyst of Probiotic Lignocellulolytic Bacteria as Starter of Agricultural By-Product

Effectivity of Biocatalyst of Probiotic Lignocellulolytic Bacteria as Starter of Agricultural By-Product

The potential of new bio-decomposers for composting sugarcane waste

The process of composting sugarcane residue by new bio-decomposer consortium formula contain specific microbes with different functions such as ligninolytic and cellulolytic microbes can improve the quality of agricultural waste. These bacteria have the potential to enhance sugarcane litter and other sugarcane residues. The fermentation process led to the C/N ratio of compost serves as a reference for the effectiveness of the decomposition process by bacteria. The research was designed as an alternative to producing organic fertilizers by using four bio-decomposer consortium formulas as ISAFCRI collection and EM4 as commercial bio-decomposer. The physicochemical characterization of 5 composts, including the C/N ratio of compost, is below 12-17, macroelements N, P, K available in compost are relatively high compared to the minimum requirement of SNI. The compost 5 with EM4 bio-decomposer appeared to have lower nutrient yields than compost using other decomposers. Compost 1 with formula one, which contains a consortium of lignocellulolytic bacteria, has excellent potential to be developed as a new bio-decomposer formula for processing sugarcane waste. The pilot test has shown that varieties of composts and organic fertilizers can be made from a mixture of sugarcane residue.

Impact of bamboo sphere amendment on composting performance and microbial community succession in food waste composting

The purpose of this study was to find an economical and effective amendment for improving composting performance and product quality, as well as to analyze the microbial community succession in the whole phase of composting. Therefore, the effect of reusable amendment bamboo sphere on composting performance and microbial community succession during food waste composting was investigated. The results showed that 6% bamboo sphere treatment had the highest degree of polymerization (3.7) and humification index (0.18). Compared with control, 6% bamboo sphere amendment increased total nitrogen (TN), phosphorus (TP) and potassium (TK) contents by 13.61%, 19% and 17.42%, respectively. Furthermore, bamboo sphere enhanced bacterial-fungal diversity and improved microbial community composition by enhancing the relative abundance of thermo-tolerance and lignocellulolytic bacteria and fungi. The five most abundant genera in bamboo sphere composting comprised Bacillus (0–71.47%), Chloroplast-norank (0–47.17%), Pusillimonas (0–33.24%), Acinetobacter (0–27.98%) and unclassified Sphingobacteriaceae (0–22.62%). Linear discriminant analysis effect size showed that Firmicutes, Thermoascaceae and Actinobacteriota, which have a relationship with the decomposition of soluble organic matter and lignocellulose, were significantly enriched in bamboo sphere treatment. Canonical correspondence analysis illustrated that total organic carbon (TOC), TK, and TP were the most important environmental factors on microbial community succession in the two composting systems. Together these results suggest that bamboo sphere as a reusable amendment can shorten maturity period, improve humification degree, increase the contents of nutrient and contribute to the succession of microbial community during food waste composting. These findings provide a theoretical basis for improving the efficiency of food waste composting.