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Microorganisms are naturally associated with plants in several ways. The study was conducted to isolate bacteria endophytes from the internal cells of roots, stems, leaves, and capitula of Senecio glaucus collected from 2 diverse (coastal and desert) habitats in Egypt. A total of 10 endophytic bacteria were obtained from the isolation; the highest diversity of bacterial endophytes was observed in desert samples roots and leaves. The isolates were recognized based on morphology, biochemical and 16S rRNA sequence genes. All isolates indicated the ability for enzyme production as amylase, cellulase, lipase, catalase, and protease in their biochemical descriptions; analyses also gave a significant indication of their potential to produce plant growth hormones, as their ability to dissolve Phosphate. In the world and Egypt, we are the first to report bacterial endophytes isolated from Senecio glaucus. This study could aid in determining the role of endophytic bacteria in severe habitats, as well as their potential applications in medicine, bioremediation, agriculture, and industry. [ABSTRACT FROM AUTHOR]

Background: Wadi El Natrun microorganisms have been considered as a new resource for natural products due to its extreme condition of salinity and alkalinity. Therefore, this study was devoted to generate metagemic library from soils collected from such an extreme environment in order to clone a novel cellulase for physique industrial applications. Results: Total soil-DNA was successfully extracted, and then digested by different restriction enzymes. Purified fragments ranged ~ 200–6500 bp were ligated and were cloned into plasmid cloning vector (pUC19) by using Escherichia coli DH5α (E. coli) host cells. A constructed metagenomic library composed of 270 clones was screened on carboxymethylcellulose (CMC) agar plate where the active clones had been characterized by the formation of the yellowish halo zone. Thereafter, clone 1 was selected as the most active as being based on cellulase activity quantification (19 μ/ml). Plasmid related to clone 1 encoded cellSNSY gene of approximately 1.5 kb was subjected to molecular characterization; the obtained partial sequence of 861 bps encoded 287 amino acids showing 76% similarity to the endoglucanase gene of Bacillus amyloliquefaciens. The recombinant cellSNSY was expressed under lacz promoter at 1 mM of isopropyl β-d-1-thiogalactopyranoside (IPTG), giving 21 μ/ml cellulase after ~ 27 h. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) and an activity staining of the recombinant cellSNSY which revealed an active band with a molecular mass ~ 59 kDa appeared in the induced sample. The maximum enzyme activity of crude cellSNSY was observed at 45 °C and for a pH of 8.5. Interestingly, the enzyme activity was slightly inhibited by ethylenediamine tetraacetic acid (EDTA) and methanol. It showed high resistance to the tested heavy metals and the surfactant which ordered Zn> (SDS,Fe)>Mn>Cu. Conclusions: This study established an easy and a skillful way to clone/express a new found cellulase gene(s) under lacZ promoter. The isolated recombinant cellSNSY showed 76% similarity to endoglucanase gene, and the enzyme showed tolerance to the mostly tested agents including heavy metals, surfactant, solvents, and EDTA. Additionally, the studied recombinant showed a high stability up to 55 °C and for alkaline pH 8.5. These features make it an ample and viable for many applications. [ABSTRACT FROM AUTHOR]

The present study aimed to isolate indigenous Trichoderma fungi possessing cellulolytic activities from different geographical locations in Egypt. Such strains can be used to convert crop residues to bioproducts, which presently is one of the most important issues in developing countries. The isolates were identified using molecular approaches and morphological characteristics. Favorable growth conditions for Trichoderma isolates (media & temperature) were assessed in vitro. The growth rate of Trichoderma isolates was assessed on two media, namely Potato Dextrose Agar (PDA) and Synthetic Nutrient Agar (SNA), and morphological parameters, i.e., shape, pigment, and edge were observed. A comparison of sequences encoding for internal transcribed spacer (ITS) and translation elongation factor 1-a (tef1) was conducted to determine the species. Cellulase assay was performed using different cellulose substrates (Swollen, CMC (low viscosity carboxymethylcellulose), and Avicel). Among the isolated fungi, Trichoderma viride EGY-T27 had the highest endoglucanase activity, while Trichoderma harzianum EGY-T30 showed the highest exoglucanase activity. A total of 27 strains of Trichoderma were identified using ITS, and the tef1 gene was sequenced for 23 strains. The tested strains were identified with acceptable quality based on ITS sequences, which ranged from 98 to 100%, except for strain MH908499 (85%). This research constitutes the most comprehensive study on screening for fungal strains with the highest biodegradable potential isolated from various locations in Egypt. [ABSTRACT FROM AUTHOR]

As a result of climate change, salinity has become a major abiotic stress that reduces plant growth and crop productivity worldwide. A variety of endophytic bacteria alleviate salt stress; however, their ecology and biotechnological potential has not been fully realized. To address this gap, a collection of 117 endophytic bacteria were isolated from wild populations of the herb Thymus vulgaris in Sheikh Zuweid and Rafah of North Sinai Province, Egypt, and identified based on their 16S rRNA gene sequences. The endophytes were highly diverse, including 17 genera and 30 species. The number of bacterial species obtained from root tissues was higher (n = 18) compared to stem (n = 14) and leaf (n = 11) tissue. The endophytic bacteria exhibited several plant growth-promoting activities in vitro , including auxin synthesis, diazotrophy, phosphate solubilization, siderophore production, and production of lytic enzymes (i.e., chitinase, cellulase, protease, and lipase). Three endophytes representing Bacillus species associated with T. vulgaris such as EGY05, EGY21, and EGY25 were selected based on their ex-situ activities for growth chamber assays to test for their ability to promote the growth of tomato (Solanum lycopersicum L.) under various NaCl concentrations (50–200 mM). All three strains significantly (P < 0.05) promoted the growth of tomato plants under salt stress, compared to uninoculated controls. In addition, inoculated tomato plants by all tested strains decreased (P < 0.05) the activity of antioxidant enzymes (superoxide dismutase, catalase, and peroxidase). Six strains, representing Bacillus and Enterobacter species EGY01, EGY05, EGY16, EGY21, EGY25, and EGY31 were selected based on in vitro antagonistic activity to F. oxysporum for pot experiments under salt stress. All tested strains reduced the disease severity index (DSI) of tomato plants at all tested salt concentrations. Gas-chromatography/mass-spectrometry analysis of cell-free extracts of B. subtilis (EGY16) showed at least ten compounds were known to have antimicrobial activity, with the major peaks being benzene, 1,3-dimethyl-, p-xylene, dibutyl phthalate, bis (2-ethylhexyl) phthalate, and tetracosane. This study demonstrates that diverse endophytes grow in wild thyme populations and that some are able to alleviate salinity stress and inhibit F. oxysporum pathogenesis, making them promising candidates for biofertilizers and biocontrol agents. [ABSTRACT FROM AUTHOR]

Of eight termite species found in Egypt, the subterranean termite Psammotermes hypostoma Desneux is considered as the most important serious pest, which destroy the wooden structures in buildings and other wood products or any material containing cellulose. Therefore, cellulases enzymes are considered the main enzymes in the digestive system of termite. The termite digestive system is considered a target for best control. This report discusses the descriptive variations of alimentary canals for the worker and the soldier, also, the detection of three digestive enzymes; two of them belonging to cellulases enzymes (endo-β-1,4-glucanase, and cellobiase (β -glucosidase) and the third is amylase in guts extracts from the termite workers and soldiers. The workers had higher endo-β-1,4-glucanase and amylase activities, while soldiers had higher cellobiase (β-gl'ucosidase) activity. It is clear that the presence of α-amylase in the digestive system of P. hypostoma workers and soldiers means that this species of termite is able to decompose starch, which explains why termites attack grain silos. Effect of temperature and PH on enzyme activity showed that the optimum temperature /PH for workers were 70 °C/ PH6 for endo- β-1,4-glucanase, 50 °C/PH6 for cellobiase (β -glucosidase) and 70 °C/pH 7 for amylase, while, in case of soldiers, optimum temperature/pH were 70 °C/PH6 for endo-β-1,4-glucanase, 40 °C/PH6 for cellobiase (β-glucosidase) and 60 °C/PH 7 for amylase. This work is the first in Egypt concerning the study of the enzymes activities of the digestive system of termite and may be considered an initial step to contribute to control this species of termite by the development of new termiticides. [ABSTRACT FROM AUTHOR]

Recently, 24 sections were characterised in the genus of Alternaria. In this work, 27 isolates of Alternaria belonging to section Alternaria were isolated from different sources in Qena governorate, Egypt. The collected strains were identified using multi-locus products of internal transcribed spacer (ITS) region, small subunit (SSU), large subunit (LSU) and Alt a1 gene. Based on four loci, the phylogenetic analysis revealed that 26 isolates (96.3% of total isolates) identified as A. alternata and the last one isolate (3.7%) as A. arborescens. The different strains of Alternaria exhibited enzymatic variability ranged from 0.1 ± 0.07–2.3 ± 0.13U/ml for cellulase and 0.6 ± 0.20–3.7 ± 0.47 U/ml (pectinase). Within A. alternata isolates, biochemical properties (Cellulase and pectinase) did not correlate either to phylogenetic analysis or strain origin. [ABSTRACT FROM AUTHOR]

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Simple Summary: Exogenous fibrolytic enzymes can improve nutrient digestibility of feeds high in fibrous content offered to Egyptian lactating buffaloes. The proposed cellulase exclusively produced in-farm using Penicillium Chrysogenum showed higher activity in previous in vitro studies. That is why it was chosen to get tested against a well-known commercial source of cellulase enzyme from the Egyptian markets for its efficiency in increasing milk productivity and composition. Profiles of amino acids and fatty acids were also recorded. The initial results highlighted a superiority of the produced enzyme (FENZ) against the commercial source (CENZ). It was also clear that FENZ can preserve higher proportions of fatty acids in the milk, primarily conjugated linoleic acid. Based on the idea rationale, our conclusion is to promote setting a small cellulase production unit in each farm in Egypt to decrease the cost of feeding by using agricultural and agro-industrial waste during the cellulase production and feeding process. The experiment was conducted to study the effects of supplementing a cellulase enzymes cocktail to lactating buffaloes' diet, on the nutrient intake, nutrient digestibility, and milk production performance and composition. Twenty-four lactating Egyptian buffaloes were assigned into one of the following treatments: CON—control consisted of a total mixed ration, CENZ—the total mixed ration supplemented by a commercial source of cellulase enzyme, FENZ—the total mixed ration supplemented with cellulase enzyme cocktail produced in-farm. Supplementing the diet with the in-farm source of cellulase (FENZ) had a significantly higher impact on crude protein, neutral detergent fiber, and acid detergent fiber digestibility. However, FENZ tended to increase the EE digestibility compared to CENZ. FENZ showed significantly higher nutrient digestibility percentages compared to other groups. Supplementing the diet with cellulase enzymes (CON vs. ENZ) significantly increased the daily milk yield and the fat correct milk yield; both yields were significantly higher with FENZ than all groups. Oleic, linoleic, and linolenic acid concentration were significantly higher with cellulase enzymes supplementation (CON vs. ENZ) and the conjugated linoleic acid concentration. Supplementing fungal cellulase enzyme produced on a farm-scale has improved milk productivity, fat yield, and milk fat unsaturated fatty acids profile in lactating buffaloes. [ABSTRACT FROM AUTHOR]

Anaerobic fungi colonize the rumen and degrade cellulose and hemicellulose, which enable them to be key players in the lignocellulose fermentation. Consequently, an expansion of knowledge about rumen fungi could increase animal productivity, utilization of lignified forages like alfalfa hay, and enhance fibrolytic enzymes production. Here, we used an Internal Transcribed Spacer 1 (ITS1) clone library to investigate the anaerobic rumen fungi in camel and to investigate their ability to produce cellulase and xylanase in vitro. Rumen fluid was collected from camels fed Egyptian clover (n = 14), and wheat straw (n = 7) and fecal samples were collected from camels fed wheat straw and concentrates (n = 5), or natural grazing plants (n = 10). Neocallimastix and Cyllamyces were the most abundant anaerobic fungi in all camel groups. An anaerobic rumen fungi media containing alfalfa hay as a carbon source was inoculated by rumen and fecal samples to assess the ability of anaerobic rumen fungi in camel gut to produce cellulase and xylanase. The anaerobic gut fungi in the camel is diverse and has cellulolytic and xylanolytic activities, fungal culture from rumen samples of camel fed wheat straw (R2) exhibited highest cellulase production. In addition, many of the sequences in the current study have no equivalent cultured representative, indicating a novel diversity within the camel gut., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)