Domestic peat pots biodegradation

Biodegradable nutrient media based on cellulose fibers and peat with added protective materials and stimulating represent the higher form of transplant used in current technologies for producing plant seedlings. Worldwide intensive development of the pots production industry (the effect of increasing demands from agriculture and their quality level in terms of degradability and operational sustainability, with outstanding results in reducing stress factors) led to fast expansion of their use with a high economic efficiency. Determination of potential and effective degradation was achieved by the method for determining cellulolytic activity in soil. Biodegradation potential recorded differences during the course of experience in the sense that it increases as the pots exposure time to treatment is higher. In conclusion, the pots treatment (planted/without plant) has a great influence on the effective biodegradation.

Polysaccharide hydrolyzing enzyme activity of bacteria, native to Apis florea gut

Introduction and Aim: Apis florea commonly known as “dwarf honey bee” harbors enormous gut bacteria that can digest complex carbohydrates and other food components. In this regard, the present investigation was focused on analyzing the polysaccharide degrading ability of bacteria isolated from the gut of honeybee, for their possible application in nutraceutical and pharmaceutical industries. Materials and Methods: Nine bacterial isolates were screened for carbohydrate degrading enzymes viz., amylase, pectinase, cellulase, tannase and laccase, using respective substrate by plate assay method. Further activities of amylase and pectinase were measured quantitatively by dinitrosalicylic acid (DNS) method. Results: All the nine selected isolates exhibited amylase and pectinase activities. However, only two isolates exhibited lignolytic and cellulolytic activity. None of the isolates showed tannin degradation. Maximum amylase activity (4.95 U/mg) was observed in Bacillus halotolerans af-M9 followed by Klebsiella oxytoca af-G4 (4.62 U/mg). With respect to pectinase activity Klebsiella pneumoniae af-E17 displayed higher activity (0.24 U/mg) followed by Klebsiella oxytoca af-G4 (0.20 U/mg). Conclusion: Habitat-specific innovations are being explored for novel compounds for therapeutic applications. This study throws a light on selection of carbohydrate degrading bacteria from a new source i.e., GUT of honeybee.

Bioethanol Production From Hassawi Rice Straw Wastes Assisted by Aspergillus sp. NAS51 Cellulosic Enzyme Under SSF and Saccharification Process With in Silico Enzyme Structural Homology Modeling

With the distribution of exploitable non-renewable energy resources, the use of lignocellulosic wastes to make bioethanol and biogas has drawn great attention from researchers. In our effort to find a potent cellulase-producing fungal strain, the fungus NAS51 was isolated from a sponge collected from the Red Sea, Jeddah, among eight isolates and selected as it displayed potent cellulolytic activity. The fungus was identified morphologically and genetically by sequencing its 18SrRNA gene as Aspergillus sp. NAS51. The cellulase activity of Aspergillus sp. NAS51 was optimized and maximum enzyme production was obtained at initial pH7, temp 30oC, incubation period 11 days, moisture content 70%, urea as a nitrogen source, and K2HPO4 (2g/L). The cellulase gene has been sequenced and the protein 3D structure was generated via in silico homology modeling. Determination of binding sites and biological annotations of the constructed protein was carried out via COACH and COFACTOR based on the I-TASSER structure prediction. To reach the maximum enzyme hydrolysis, the rice straw collected from Al-Ahsa, Kingdom of Saudi Arabia was pretreated with NaOH 1.5% to remove lignin and to enhance the saccharification process by cellulase enzyme. The saccharified product was measured using HPLC, fermented by S. cerevisiae and the bioethanol yield produced from the fermentation was 0.454 ml ethanol/g fermentable sugars.

Comparative assessment of the ecological state of Timiryazevsky district forest park zones in Moscow

The article presents the results of a comparative environmental assessment of the quality of the environment in the central and outlying zones of two forest parks, contrasting in area, types and magnitude of anthropogenic load, - the Experimental Forest Station and the Dubki Culture and Recreation Park, located in the Timiryazevsky district of Moscow. The quality of the environment in the undisturbed forest biocenosis in the center of the Experimental Forest Station corresponded to the quality of the environment in the rural areas of the Moscow Region, while the environmental situation in the outlying zones of both forest parks bordering various urban infrastructure facilities deviated to varying degrees from the conditional norm. The worst indicators of the environmental quality and forest stand conditions were noted in the recreational zones located at the III-IV stage of digression, as well as in the zones bordering the roads, within which the degree of fluctuating asymmetry of birch leaves was suspended and the cellulolytic activity of the soil was 1.5-2.5 times lower than the background. The combination of recreational and transport loads reduced the quality of the environment in the Dubki park to a critical level. Keywords: CITY FOREST, BORDERLAND, ANTHROPOGENIC LOAD, POLLUTION, RECREATION, DEGRADATION, FLUCTUATING ASYMMETRY, CELLULOLYTIC ACTIVITY, APPLICATION METHOD, AIRBORNE POLLUTION, SNOW COVER

Disruption of the Snf1 Gene Enhances Cell Growth and Reduces the Metabolic Burden in Cellulase-Expressing and Lipid-Accumulating Yarrowia lipolytica

Yarrowia lipolytica is known to be capable of metabolizing glucose and accumulating lipids intracellularly; however, it lacks the cellulolytic enzymes needed to break down cellulosic biomass directly. To develop Y. lipolytica as a consolidated bioprocessing (CBP) microorganism, we previously expressed the heterologous CBH I, CBH II, and EG II cellulase enzymes both individually and collectively in this microorganism. We concluded that the coexpression of these cellulases resulted in a metabolic drain on the host cells leading to reduced cell growth and lipid accumulation. The current study aims to build a new cellulase coexpressing platform to overcome these hinderances by (1) knocking out the sucrose non-fermenting 1 (Snf1) gene that represses the energetically expensive lipid and protein biosynthesis processes, and (2) knocking in the cellulase cassette fused with the recyclable selection marker URA3 gene in the background of a lipid-accumulating Y. lipolytica strain overexpressing ATP citrate lyase (ACL) and diacylglycerol acyltransferase 1 (DGA1) genes. We have achieved a homologous recombination insertion rate of 58% for integrating the cellulases-URA3 construct at the disrupted Snf1 site in the genome of host cells. Importantly, we observed that the disruption of the Snf1 gene promoted cell growth and lipid accumulation and lowered the cellular saturated fatty acid level and the saturated to unsaturated fatty acid ratio significantly in the transformant YL163t that coexpresses cellulases. The result suggests a lower endoplasmic reticulum stress in YL163t, in comparison with its parent strain Po1g ACL-DGA1. Furthermore, transformant YL163t increased in vitro cellulolytic activity by 30%, whereas the “total in vivo newly formed FAME (fatty acid methyl esters)” increased by 16% in comparison with a random integrative cellulase-expressing Y. lipolytica mutant in the same YNB-Avicel medium. The Snf1 disruption platform demonstrated in this study provides a potent tool for the further development of Y. lipolytica as a robust host for the expression of cellulases and other commercially important proteins.

Protection of spring wheat with biopreparations and fungicides in the forest steppe of Priobye: I. First results in extreme weather conditions

The paper presents data on a comparative test of the efficacy of chemical, fungal and bacterial fungicides in limiting the harmfulness of main diseases of spring wheat. The research was carried out on leached chernozem of the forest-steppe of Priobye of the Novosibirsk region. It was shown that Sternifag, SP reduces the development of root rot at the end of the growing season by 48 %, which is comparable to the effect of a chemical dressing agent Scarlet, ME (imazalil+tebuconazole) and is slightly inferior to the action of combined application of fungal preparation Trichocin, SP with the bacterial preparation Vitaplan, SP (55 %). Preplanting seed treatment effectively reduced the development of leaf infections: Scarlet, ME suppressed the development of Septoria blotch by 54 %, Scarlet, ME + Vitaplan, SP – of powdery mildew by 69 %, Trichotsin,SP + Vitaplan, SP – of brown rust by 74 %. Fungicide Titul 390, KKR reduced the development of these diseases by 60, 81 and 85 %, respectively. Alirin-B, W with Trichocin, SP suppressed brown rust by 64 %. Cellulolytic activity increased 1.3–1.9 times compared to the control as a result of the action of biological products and Sternifag, SP. The amount of plant residues decreased 2.4 and 1.9 times 15 and 30 days after application. The greatest increase in yield was provided by chemical fungicides – 0.7 t / ha, they were not inferior to the use of Alirin-B, W with Vitaplan, SP against the background of etching with Scarlet, ME fungicide.

Cellulose-containing waste recycling using fungi

Accumulation of plant waste is a serious environmental problem. Mushrooms with high cellulolytic activity can process it into valuable products that will be useful in solving various industries and agriculture problems. The enzymes of the cellulolytic complex include 1,4-β-D-glucan-4-glucanohydrolase, exo-1,4-β-glucosidase, cellobiohydrolase, β-glucosidase. 1,4-β-D-glucan-4-glucanohydrolases destroy β-1,4-glycosidic bonds within the chain of cellulose and lichenin polysaccharides. Exoglucanases destroy β-1,3- and β-1,4-glycosidic bonds at the end of the molecule. Cellobiohydrolases cleave β-1,4-glycosidic bonds to form cellobiose and glucose. β-glucosidase complete the process of destruction. Fungi with high cellulolytic activity include both representatives of the Ascomycota and Basidiomycota divisions. Ascomycete Chaetomium globosum produces endoglucanases of two families and 8 cellobiohydrolases. Myceliophthora thermophila also produces endoglucanases and cellobiohydrolases, the most abundant of which is Mt Cel7A. The fungus is a promising producer of thermostable enzymes. Trichoderma reesei has a long history of safe use as a source of highly active cellulolytic enzymes and other valuable metabolites. LPMOs of the cellulolytic fungus Thielavia terrestris are considered auxiliary enzymes, but can negatively affect the main enzymes of the complex. Irpex lacteus also produces LPMO and a complete cellulolytic enzyme complex. The cellulolytic activity of fungi and their ability to grow on cheap substrates can be used to bioconvert plant waste into valuable products. One of the ways to utilize them is to convert into compound feed with a high protein content through the use of starter cultures. The use of mushrooms will increase the content of protein and simple carbohydrates, enrich the feed with fats. Another method is to obtain cellulases, which are widely used in many industries. Thanks to the production of biodiesel and bioethanol from cellulose-containing raw materials it is possible to solve the problem of lack of fuel by replacing energy carriers from non-renewable energy sources with their environmentally friendly counterparts. They are less toxic than diesel and gasoline and are also made from renewable resources.

The qualitative screening of cellulolytic, chitinolytic, IAA-producing, and phosphate solubilizing bacteria from black soldier fly larvae (Hermetia illucens L.)

Black soldier fly (Hermetia illucens L.) larvae are widely used in organic waste management. Its ability to digest organic compound was supported by the diversity of bacteria which produce various enzymes inside the larvae bodies. The exploration of potential bacteria in BSF larvae may have advantages for the agricultural field. This study aimed to screen cellulolytic, chitinolytic, phosphate solubilizing, and IAA-producing bacteria from BSF larvae. A total of 22 isolates were qualitatively screened using various media. Among the 22 isolates, five isolates showed positive results of cellulolytic activity; six isolates were able to digest chitin; nine isolates have positive result of IAA-producing test; and five isolates could solubilize phosphate in Pikovskaya’s agar. There were two isolates, B11 and B15, that gave positive result in three tests, those are on cellulolytic, phosphate solubilizing, and IAA producing test. Molecular identification of B11 showed that the isolate was similar to Bacillus altitudinis (100%) and B15 was closed to Klebsiella oxytoca (99.73%).

Isolation and Characterization of Cellulolytic Bacteria Diversity in Peatland Ecosystem and Their Cellulolytic Activities

Peatlands are terrestrial wetland ecosystems formed from piles of organic matter that decompose into organic deposits. Peat soil has a high potential to produce cellulose which, can be reused by cellulolytic bacteria. This study aims to find out the potential strain of cellulolytic bacteria isolated from peatland ecosystems. The method used was experimental, sequentially, the stages are isolation and screening for cellulolytic bacteria, quantitative testing of cellulolytic activity, characterizing the morphology and physiology of bacteria, and the identification of bacteria based on Bergey’s Manual of Determinative Bacteriology. The screening results obtained seven isolates of cellulolytic bacteria capable of hydrolysed cellulose on 1% Carboxy Methyl Cellulose (CMC) Agar Medium, namely SPS1, SPS2, SPS 3, SDG1, SDG 2, SPW1, and SPW4. Three of seven isolates obtained the highest cellulolytic index sequentially, namely SPS2 of 2.82, SPS3 of 2.65, and SDG1 of 2.47. The cellulolytic activity was indicated by the value of a halo zone around the colonies on 1 % CMC medium after being dripped with Congo red. The halo zone is an early indication to determine the ability of bacteria to decompose cellulose. Based on Bergey’s Manual of Determinative Bacteriology showed that the three isolates had the same characteristics as the genus Bacillus, Lactobacillus and Corynebacterium.