Chitinase Enzyme Research Articles

Morphological and Molecular Characteristics of Endophytic Fungi in Sugarcane as Antagonists of the Pathogen Fusarium sacchari

Fusarium sacchari is a pathogenic fungus that causes the pokkah boeng disease in sugarcane plants. The symptoms of pokkah boeng disease are systemic, spreading throughout all parts of the plant. The control measures implemented so far still rely on synthetic pesticides but have not yielded optimal results and are not environmentally friendly. One of the environmentally friendly control methods is the use of endophytic fungi. Endophytic fungi live within plant tissues without causing disease symptoms. This research aims to discover endophytic fungi derived from sugarcane and evaluate their ability to suppress the growth of the pathogen F. sacchari. The research began with the isolation of sugarcane tissue, followed by the morphological and molecular characterization of endophytic fungi and testing their inhibitory capacity against the pathogen F. sacchari. Morphological identification was based on colony and microscopic characteristics, while molecular identification was conducted using PCR and sequencing, with similarities based on GenBank. Inhibition tests were conducted through dual culture and volatile compound testing, as well as enzyme production. The research results obtained 38 endophytic fungal isolates from sugarcane plants that have the ability to inhibit the pathogen F. sacchari. Five of these isolates showed the highest inhibition against F. sacchari and produced cellulase, protease, and chitinase enzymes. Molecular identification results indicated that these five-sugarcane endophytic fungal isolates are Daldinia eschscholdzii, Hypoxylon pulicicidum, Trichoderma virens, Trichoderma harzianum, and Diaporthe phaseolorum. The endophytic fungus T. harzianum provides the highest inhibition rate of 83.33% in dual culture and 55.5% inhibition through the production of volatile compounds. Keywords: Endophytic fungi, inhibitory power, Fusarium sacchari, morphological characteristics, molecular characteristics, pokkah boeng disease, sugarcane plants.

Endophytic Actinomycetes of Liliaceae Plants as Biocontrol Agents of Fusarium oxysporum f.sp. cepae Causes of Basal Plate Rot Disease on Shallots

Basal plate rot disease is one of the critical diseases in shallot plants. Control using synthetic chemical fungicides is still unable to overcome this problem, and it hurts the environment and reduces the population of essential microbes in plants. Endophytic actinomycetes have potential as biocontrol agents. They are reported to be able to inhibit the growth of pathogens, induce plant resistance, produce cell wall degrading enzymes, and promote growth. This research aims to obtain endophytic actinomycete isolates that have the potential to inhibit the growth of the fungus Fusarium. oxysporum f.sp. cepae causes of basal plate rot disease in shallot, and evaluate its inhibitory mechanism. Endophytic actinomycetes were isolated from tubers and roots of Liliaceae plants collected from shallots-production center area. The isolate obtained was tested for biosafety and continued with its inhibitory effectiveness against the fungus F. oxysporum f.sp. cepae in vitro, ability to induce resistance, and plant growth promotion test. The six best isolates were selected based on weighting using AHP and identified molecularly. The endophytic actinomycetes of Liliaceae plants can inhibit the growth of F. oxysporum f.sp. cepae up to 63.49% with an antibiosis mechanism, producing chitinase enzymes that cause lysis, induce resistance, and produce growth hormones such as IAA. Streptomyces sp. can inhibit the fungus F. oxysporum f.sp. cepae causes basal plate rot disease on shallot by producing antifungal compounds and chitinase enzymes, inducing resistance, and producing growth hormone.

Computational identification and characterization of chitinase 1 and chitinase 2 from neotropical isolates of Beauveria bassiana.

The fungus Beauveria bassiana is widely used for agronomical applications, mainly in biological control. B. bassiana uses chitinase enzymes to degrade chitin, a major chemical component found in insect exoskeletons and fungal cell walls. However, until recently, genomic information on neotropical isolates, as well as their metabolic and biotechnological potential, has been limited. Eight complete B. bassiana genomes of Neotropical origin and three references were studied to identify chitinase genes and its corresponding proteins, which were curated and characterized using manual curation and computational tools. We conducted a computational study to highlight functional differences and similarities for chitinase proteins in these Neotropical isolates. Eleven chitinase 1 genes were identified, categorized as chitinase 1.1 and chitinase 1.2. Five chitinase 2 genes were identified but presented a higher sequence conservation across all sequences. Interestingly, physicochemical parameters were more similar between chitinase 1.1 and chitinase 2 than between chitinase 1.1 and 1.2. Chitinases 1 and 2 demonstrated variations, especially within chitinase 1, which presented a potential paralog. These differences were observed in their physical parameters. Additionally, CHIT2 completely lacks a signal peptide. This implies that CHIT1 might be associated with infection processes, while CHIT2 could be involved in morphogenesis and cellular growth. Therefore, our work highlights the importance of computational studies on local isolates, providing valuable resources for further experimental validation. Intrinsic changes within local species can significantly impact our understanding of complex pathogen-host interactions and offer practical applications, such as biological control.

Investigating the antifungal potential of genetically modified hybrid chitinase enzymes derived from Bacillus subtilis and Serratia marcescens.

Chitinases are glycosyl hydrolase enzymes that break down chitin, an integral component of fungal cell walls. Bacteria such as Bacillus subtilis and Serratia marcescens produce chitinases with antifungal properties. In this study, we aimed to generate hybrid chitinase enzymes with enhanced antifungal activity by combining functional domains from native chitinases produced by B. subtilis and S. marcescens. Chitinase genes were cloned from both bacteria and fused together using overlap extension PCR. The hybrid constructs were expressed in E. coli and the recombinant enzymes purified. Gel electrophoresis and computational analysis confirmed the molecular weights and isoelectric points of the hybrid chitinases were intermediate between the parental enzymes. Antifungal assays demonstrated that the hybrid chitinases inhibited growth of the fungus Fusarium oxysporum significantly more than the native enzymes and also showed fungicidal activity against Candida albicans, Alternaria solani, and Rhizoctonia solani. The results indicate that hybrid bacterial chitinases are a promising approach to engineer novel antifungal proteins. This study provides insight into structure-function relationships of chitinases and strategies for generating biotherapeutics with enhanced bioactive properties. These hybrid chitinases result in a more potent and versatile antifungal agent.

Trichoderma harzianum TIND02 upregulates the expression of pathogenesis-related genes and enzymes and enhances gray blight resistance in tea

The gray blight incited by Pestalotiopsis and allied genera is a prevalent disease affecting tea cultivation, and managing it with Trichoderma spp. is an alternative to synthetic fungicides. Plants modify their arsenal system against pathogens when they are exposed to Trichoderma spp., which produces proteins and enzymes associated with pathogenesis. Understanding the expression pattern of defense-related markers will help in developing gray blight resistance tea cultivars. Thus, this study intended to induce resistance against gray blight in tea by Trichoderma harzianum TIND02. For this, a total of eight Trichoderma isolates originated from organic tea rhizospheres were characterized and evaluated for their efficacy. Dual culture test revealed isolate TIND02 as the most potential candidate with 74.6% inhibitory activity against gray blight pathogen Pseudopestalotiopsis theae. Molecular characterization based on ITS and tef-1 alpha genes confirmed isolate TIND02 as T. harzianum. Scanning electron microscopic study showed the mycoparasitic nature of T. harzianum TIND02 (TH-TIND02) to Ps. theae. The ethyl acetate extract of TH-TIND02 at 100 and 200 μg mL−1 showed potential inhibitory activity (>69.9%) against Ps. theae which confirmed the presence of higher volatile metabolites. Gas chromatography–Mass spectrometry study revealed that ethyl acetate extract of TH-TIND02 was composed of 21 major and minor volatile organic compounds with acetamide, 2, 2, 2-trifluoro-N, N-bis trimethyIsilyl–C (94.74%) as a major component. The isolate also produced chitinase, cellulase, β-1, 3 glucanase, and protease hydrolytic enzymes. Nursery experiments revealed that 2% and 5% doses (2 × 106 CFU mL−1) of TH-TIND02 significantly reduced respective 65.0% and 70.0% disease severity over control with improved plant growth. Besides, expressions of defense-related enzymes (chitinase, pHenolics, peroxidase, phenylalanine ammonia lyase, β-1, 3-glucanase, and polyphenol oxidase) and pathogenesis-related genes (chitinase and β-1, 3-glucanase) due to TH-TIND02 were determined. The secretion of defense-related enzymes was highly upregulated in plants applied with TH-TIND02 followed by Ps. theae inoculation compared to controls. The RT-qPCR analysis showed that the expression of both genes in co-inoculated plants was two-fold higher than in control after 21-day post incubation. These results suggest that TH-TIND02 application reduced gray blight severity by elevated enzyme activity and overexpressed pathogenesis-related genes in tea plants which offer for its eco-friendly and sustainable use as a bio-fungicide in tea gardens.

Genomics, Proteomics, and Antifungal Activity of Chitinase from the Antarctic Marine Bacterium Curtobacterium sp. CBMAI 2942.

This study aimed to evaluate the genomic profile of the Antarctic marine Curtobacterium sp. CBMAI 2942, as well as to optimize the conditions for chitinase production and antifungal potential for biological control. Assembly and annotation of the genome confirmed the genomic potential for chitinase synthesis, revealing two ChBDs of chitin binding (Chi C). The optimization enzyme production using an experimental design resulted in a 3.7-fold increase in chitinase production. The chitinase enzyme was identified by SDS-PAGE and confirmed through mass spectrometry analysis. The enzymatic extract obtained using acetone showed antifungal activity against the phytopathogenic fungus Aspergillus sp. series Nigri CBMAI 1846. The genetic capability of Curtobacterium sp. CBMAI 2942 for chitin degradation was confirmed through genomic analysis. The basal culture medium was adjusted, and the chitinase produced by this isolate from Antarctica showed significant inhibition against Aspergillus sp. Nigri series CBMAI 1846, which is a tomato phytopathogenic fungus. This suggests that this marine bacterium could potentially be used as a biological control of agricultural pests.

Literatur Review: Siderophore Activity and Campability of Bacillus as Pathogen Controller of Eggplant Plant

Solanum melongena (eggplant) is an important cultivated vegetable crop with a very high consumer level, both in tropical and subtropical regions. Eggplant is widely favored by the public because in addition to having a good taste, it can also be made pickled and candied eggplant, and is good as a source of nutrition in supporting public health. Siderophores are metal-coating agents with low molecular mass (200-2000 Da) produced by microorganisms and plants, especially under Fe-limiting conditions. Antagonistic bacteria generally live colonizing roots an d are beneficial, because they are able to increase plant growth and induce systemic resistance. one species of the genus Bacillus spp. namely B. subtilis is able to produce amylase, protease, pullunase, chitinase, xylanase and lipase enzymes which are secondary metabolites to control pathogens and spur plant growth. This article is sourced from relevant literature studies related to the title. The purpose of writing the article is to determine the benefits of siderophores as pathogen disease control in eggplant plants. Results successfully inhibited the growth of pathogens.

Extremozymes and compatible solute production potential of halophilic and halotolerant bacteria isolated from crop rhizospheric soils of Southwest Saurashtra Gujarat

Halophiles are one of the classes of extremophilic microorganisms that can flourish in environments with very high salt concentrations. In this study, fifteen bacterial strains isolated from various crop rhizospheric soils of agricultural fields along the Southwest coastline of Saurashtra, Gujarat, and identified by 16S rRNA gene sequencing as Halomonas pacifica, H. stenophila, H. salifodinae, H. binhaiensis, Oceanobacillus oncorhynchi, and Bacillus paralicheniformis were investigated for their potentiality to produce extremozymes and compatible solute. The isolates showed the production of halophilic protease, cellulase, and chitinase enzymes ranging from 6.90 to 35.38, 0.004–0.042, and 0.097–0.550 U ml−1, respectively. The production of ectoine-compatible solute ranged from 0.01 to 3.17 mg l−1. Furthermore, the investigation of the ectoine-compatible solute production at the molecular level by PCR showed the presence of the ectoine synthase gene responsible for its biosynthesis in the isolates. Besides, it also showed the presence of glycine betaine biosynthetic gene betaine aldehyde dehydrogenase in the isolates. The compatible solute production by these isolates may be linked to their ability to produce extremozymes under saline conditions, which could protect them from salt-induced denaturation, potentially enhancing their stability and activity. This correlation warrants further investigation.

Fungal endo and exochitinase production, characterization, and application for Candida biofilm removal.

Chitinases are promising enzymes for a multitude of applications, including chitooligosaccharide (COS) synthesis for food and pharmaceutical uses and marine waste management. Owing to fungal diversity, fungal chitinases may offer alternatives for chitin degradation and industrial applications. The rapid reproduction cycle, inexpensive growth media, and ease of handling of fungi may also contribute to reducing enzyme production costs. Thus, this study aimed to identify fungal species with chitinolytic potential and optimize chitinase production by submerged culture and enzyme characterization using shrimp chitin. Three fungal species, Coriolopsis byrsina, Trichoderma reesei, and Trichoderma harzianum, were selected for chitinase production. The highest endochitinase production was achieved in C. byrsina after 168h cultivation (0.3 U mL- 1). The optimal temperature for enzyme activity was similar for the three fungal species (up to 45 and 55 ºC for endochitinases and exochitinases, respectively). The effect of pH on activity indicated maximum hydrolysis in acidic pH (4-7). In addition, the crude T. reesei extract showed promising properties for removing Candida albicans biofilms. This study showed the possibility of using shrimp chitin to induce chitinase production and enzymes that can be applied in different industrial sectors.

Potential of Streptomyces spp. From Peanut Plant Soil as an Entomopathogen of Pests Spodoptera Litura

Peanuts are agricultural commodities that have high economic value and play an important role in meeting human needs, namely as a source of vegetable protein, oil and other nutrients, but domestic peanut production has not been able to meet the needs of the Indonesian people. The national demand for peanuts reaches 856.1 thousand tons per year, and the average consumption of peeled peanuts is 0.32 kg per capita every year. [1] In 2013 peanut production was 701,680 tons, then there was a decrease in production in 2014 to 638,896 tons, and continued until 2015 to 605,449 tons, thus showing a 13.7% decrease that occurred from 2013 to 2015. Low productivity is caused by various factors, one of which is the attack of pests and plant diseases. This study aims to determine the type of Streptomyces spp. Microbes with high chitinolytic content that can control armyworm pests (S.litura) on peanut plants. and influence of biological control agency Streptomyces spp as an entomopathogen of insect pests S. litura. This study was able to improve understanding of the influence of the biological control agency Streptomyces spp as an entomopathogen of S. litura insect pests to protect plants in the future. The results of the exploration of Streptomyces sp. acquired Colonies are irregular and branched coccus-shaped. The colony is tightly attached to the GNA medium, wavy white with a notched surface and a starchy texture. In addition, it has the largest chitinase enzyme content with a chitin zone diameter of 3 cm. PCR test Based on BLAST® result tabulation data that isolates belong to the genus Streptomyces sp. with an identity percentage of 99.86% with Streptomyces sp. VEL gene 17 to 16 rRNA, partial sequence with access code AB914463.2 The highest mortality was in the treatment (S0 RP K3) and (S1 RP K3) there was 60% this showed that with the administration of Streptomyces sp. With a concentration of 75% can cause very high mortality with abdominal contact poison in S. Litura pests

Exploring chitin: novel pathways and structures as promising targets for biopesticides.

Chitin, the most prevalent polymer in nature, a significant structural polysaccharide that comes in second only to cellulose. Chitin is a crucial component of fungal cell walls and also present in many other creatures, such as viruses, plants, animals, insect exoskeletons, and crustacean shells. Chitin presents itself as a promising target for the development of biopesticides. It focuses on unraveling the unique structures and biochemical pathways associated with chitin, aiming to identify vulnerabilities that can be strategically leveraged for effective and environmentally sustainable pest control. It involves a comprehensive analysis of chitinase enzymes, chitin biosynthesis, and chitin-related processes across diverse organisms. By elucidating the molecular intricacies involved in chitin metabolism, this review seeks to unveil potential points of intervention that can disrupt essential biological processes in target pests without harming non-target species. This holistic approach to understanding chitin-related pathways aims to inform the design and optimization of biopesticides with enhanced specificity and reduced ecological impact. The outcomes of this study hold great promise for advancing innovative and eco-friendly pest management strategies. By targeting chitin structures and pathways, biopesticides developed based on these findings may offer a sustainable and selective alternative to conventional chemical pesticides, contributing tothe ongoing efforts towards more environmentally conscious and effective pest control solutions.

Chitinase Producing Gut-Associated Bacteria Affected the Survivability of the Insect Spodoptera frugiperda.

Fall armyworm (Spodoptera frugiperda) is a highly destructive maize pest that significantly threatens agricultural productivity. Existing control methods, such as chemical insecticides and entomopathogens, lack effectiveness, necessitating alternative approaches. Gut-associated bacteria were isolated from the gut samples of fall armyworm and screened based on their chitinase and protease-producing ability before characterization through 16S rRNA gene sequence analysis. The efficient chitinase-producing Bacillus licheniformis FGE4 and Enterobacter cloacae FGE18 were chosen to test the biocontrol efficacy. As their respective cell suspensions and extracted crude chitinase enzyme, these two isolates were applied topically on the larvae, supplemented with their feed, and analyzed for their quantitative food use efficiency and survivability. Twenty-one high chitinase and protease-producing bacterial isolates were chosen. Five genera were identified by 16S rRNA gene sequencing: Enterobacter, Enterococcus, Bacillus, Pantoea, and Kocuria. In the biocontrol efficacy test, the consumption index and relative growth rate were lowered in larvae treated with Enterobacter cloacae FGE18 by topical application and feed supplementation. Similarly, topical treatment of Bacillus licheniformis FGE4 to larvae decreased consumption index, relative growth rate, conversion efficiency of ingested food, and digested food values. The presence of gut bacteria with high chitinase activity negatively affects insect health. Utilizing gut-derived bacterial isolates with specific insecticidal traits offers a promising avenue to control fall armyworms. This research suggests a potential strategy for future pest management.

Utilizing chitooligosaccharides from shrimp waste biodegradation via recombinant chitinase A: a promising approach for emulsifying hydrocarbon and bioremediation

BackgroundHydrocarbon pollution stemming from petrochemical activities is a significant global environmental concern. Bioremediation, employing microbial chitinase-based bioproducts to detoxify or remove contaminants, presents an intriguing solution for addressing hydrocarbon pollution. Chitooligosaccharides, a product of chitin degradation by chitinase enzymes, emerge as key components in this process. Utilizing chitinaceous wastes as a cost-effective substrate, microbial chitinase can be harnessed to produce Chitooligosaccharides. This investigation explores two strategies to enhance chitinase productivity, firstly, statistical optimization by the Plackett Burman design approach to evaluating the influence of individual physical and chemical parameters on chitinase production, Followed by response surface methodology (RSM) which delvs into the interactions among these factors to optimize chitinase production. Second, to further boost chitinase production, we employed heterologous expression of the chitinase-encoding gene in E. coli BL21(DE3) using a suitable vector. Enhancing chitinase activity not only boosts productivity but also augments the production of Chitooligosaccharides, which are found to be used as emulsifiers.ResultsIn this study, we focused on optimizing the production of chitinase A from S. marcescens using the Plackett Burman design and response surface methods. This approach led to achieving a maximum activity of 78.65 U/mL. Subsequently, we cloned and expressed the gene responsible for chitinase A in E. coli BL21(DE3). The gene sequence, named SmChiA, spans 1692 base pairs, encoding 563 amino acids with a molecular weight of approximately 58 kDa. This sequence has been deposited in the NCBI GenBank under the accession number "OR643436". The purified recombinant chitinase exhibited a remarkable activity of 228.085 U/mL, with optimal conditions at a pH of 5.5 and a temperature of 65 °C. This activity was 2.9 times higher than that of the optimized enzyme. We then employed the recombinant chitinase A to effectively hydrolyze shrimp waste, yielding chitooligosaccharides (COS) at a rate of 33% of the substrate. The structure of the COS was confirmed through NMR and mass spectrometry analyses. Moreover, the COS demonstrated its utility by forming stable emulsions with various hydrocarbons. Its emulsification index remained stable across a wide range of salinity, pH, and temperature conditions. We further observed that the COS facilitated the recovery of motor oil, burned motor oil, and aniline from polluted sand. Gravimetric assessment of residual hydrocarbons showed a correlation with FTIR analyses, indicating the efficacy of COS in remediation efforts.ConclusionsThe recombinant chitinase holds significant promise for the biological conversion of chitinaceous wastes into chitooligosaccharides (COS), which proved its potential in bioremediation efforts targeting hydrocarbon-contaminated sand.

Remote loop evolution reveals a complex biological function for chitinase enzymes beyond the active site

Loops are small secondary structural elements that play a crucial role in the emergence of new enzyme functions. However, the evolutionary molecular mechanisms how proteins acquire these loop elements and obtain new function is poorly understood. To address this question, we study glycoside hydrolase family 19 (GH19) chitinase—an essential enzyme family for pathogen degradation in plants. By revealing the evolutionary history and loops appearance of GH19 chitinase, we discover that one loop which is remote from the catalytic site, is necessary to acquire the new antifungal activity. We demonstrate that this remote loop directly accesses the fungal cell wall, and surprisingly, it needs to adopt a defined structure supported by long-range intramolecular interactions to perform its function. Our findings prove that nature applies this strategy at the molecular level to achieve a complex biological function while maintaining the original activity in the catalytic pocket, suggesting an alternative way to design new enzyme function.

Evaulation of Effective Antagonistic Yeasts in Kalasin Province, a Biocontrol Agent against the Fungal Colletotrichum capsici Caused Anthracnose Diseases in Chili Fruits

Primary screening of epiphytic and endophytic yeasts, the majority yeast was found from rhizosphere soil (21 isolates, 31.81%), and 5 antagonistic yeasts can have inhibited the growth of mycelia of C. capsici up to 60%. Efficacy of five antagonistic yeasts were screened under plant nurseries conditions. The result found all isolates were tested and compared with control and chemical plots. The result of plant height showed that, yeast isolate KS34 had highest of plant height at 45.80 cm. For the result of branch per plant of chili plant found isolate KS37 showed highest of branch per plant at 16.60 branches and the flower of chili per plant presented that isolate KS37 had highest of flower at 18.60 flowers. The result of anthracnose disease control by antagonistic yeasts in disease incidence and category mean as plant resistance. These results found that, Isolates KS46 had a great disease incidence at 7.80% that mean this isolate prove chili plant to resistance to C. capsisci. Addition, isolate KS46 had highest of activity of chitinase enzyme at 170.72 U/ml. Isolate KS46 identified by D1/D2 domain of 26S ribosomal DNA sequencing. The sequence analysis showed maximum identity of 100% with Candida haemulonii. This assumed C. haemulonii was showed the best to control C. capsici. For confirmed this result, all isolates were determined the mode of action by studied in relationship between antagonist isolates. The action of yeast isolate could competition the nutrient with mycelia of pathogen. This mode effect to C. capsici loss nutrient caused the pathogen get stuck to braked and died later.

Gene Cloning, Heterologous Expression, and In Silico Analysis of Chitinase B from Serratia marcescens for Biocontrol of Spodoptera frugiperda Larvae Infesting Maize Crops.

Spodoptera frugiperda, the fall armyworm (FAW), is a highly invasive polyphagous insect pest that is considered a source of severe economic losses to agricultural production. Currently, the majority of chemical insecticides pose tremendous threats to humans and animals besides insect resistance. Thus, there is an urgent need to develop new pest management strategies with more specificity, efficiency, and sustainability. Chitin-degrading enzymes, including chitinases, are promising agents which may contribute to FAW control. Chitinase-producing microorganisms are reported normally in bacteria and fungi. In the present study, Serratia marcescens was successfully isolated and identified from the larvae of Spodoptera frugiperda. The bacterial strain NRC408 displayed the highest chitinase enzyme activity of 250 units per milligram of protein. Subsequently, the chitinase gene was cloned and heterologously expressed in E. coli BL21 (DE3). Recombinant chitinase B was overproduced to 2.5-fold, driven by the T7 expression system. Recombinant chitinase B was evaluated for its efficacy as an insecticidal bioagent against S. frugiperda larvae, which induced significant alteration in subsequent developmental stages and conspicuous malformations. Additionally, our study highlights that in silico analyses of the anticipated protein encoded by the chitinase gene (ChiB) offered improved predictions for enzyme binding and catalytic activity. The effectiveness of (ChiB) against S. frugiperda was evaluated in laboratory and controlled field conditions. The results indicated significant mortality, disturbed development, different induced malformations, and a reduction in larval populations. Thus, the current study consequently recommends chitinase B for the first time to control FAW.

Bacillus sp. alone or combined with salicylic acid inhibited Trichoderma spp. infection on harvested white Hypsizygus marmoreus.

White Hypsizygus marmoreus is a popular edible mushroom. It is rich in nutrition and flavor but vulnerable to fungal disease, resulting in nutrient loss and aging. In this study, the pathogenic fungus Trichoderma spp. BBP-6 and its antagonist Bacillus sp. 1-23 were isolated and identified. The negative effects caused by this pathogen were judged by detecting a series of changes in the infected white H. marmoreus. The effects of Bacillus sp. 1-23 on Trichoderma spp. BBP-6 and the infected white H. marmoreus were detected. The effect of Bacillus sp. 1-23 treatment combined with salicylic acid (SA) was also considered. The results showed that Trichoderma spp. BBP-6 could affect the activities of antioxidant enzymes PAL, POD, CAT, SOD, GR, PPO, and APX to interfere with the stability of the white H. marmoreus antioxidant enzyme system and cause the mushroom severe browning and nutrition loss, as well as general quality deterioration. Bacillus sp. 1-23 could produce chitinase and chitosanase enzymes to inhibit Trichoderma spp. BBP-6 directly. SA reinforced this inhibitory. Bacillus sp. 1-23 alone or combined with SA could help white H. marmoreus from the Trichoderma spp. BBP-6 infection to effectively maintain nutrients, restore and stabilize the antioxidant system, and reduce the production of malondialdehyde, superoxide anion and hydrogen peroxide. Thus, such treatments could be considered potential methods to alleviate damage from disease and extend the shelf life of white H. marmoreus.

Biological Roles of Chitinase 1 in Pathogenic Conditions

Chitin is a prevalent biopolymer found in arthropods such as mollusks, crustaceans, nematodes, worms, and insects. Chitin do not consider as a structural component in mammals. Chitinase enzymes are a group of proteins that have a special ability to attach to and break down chitin, and they are widely preserved throughout evolution. Chitinase in humans was first identified by its ability to break down chitotrioside which is considered as its substrates and for that reason it named chitotriosidase which is also known as CHIT1 or chitinase-1. It is primarily secreted from macrophages during their activated phase in both typical and inflammatory circumstances. Individuals with Gaucher's disease (GD) have a notable rise in CHIT1 activity in both plasma and tissues compared to those without the condition. GD is a hereditary ailment characterized by lipid buildup in certain organs’ macrophages such as the lungs, spleen, liver, kidneys, bone marrow, and brain. Serum CHIT1 levels are commonly utilized as a robust diagnostic biomarker to assess the effectiveness of therapy for several diseases that we reviewed in this review.

Chitinase Enzyme-Producing Endophytic Bacterias From the Roots of the Plant Gembolo (Dioscorea bulbifera): Isolation, Characterization and its Potential as an Antifungal Agent

Chitinase is an enzyme of the chitinolytic group that has many roles in agriculture, especially as an antifungal, because chitin is one of the constituent components of the fungal cell wall. This study aimed to isolate and identify endophytic bacteria from gembolo (Dioscorea bulbifera) roots and to characterize the chitinase enzyme from these endophytic bacteria to be used as an antifungal. Isolation and identification of gembolo plant root endophytic bacteria using PCR method of 16S rRNA gene amplification and sequencing. Characterization of the chitinase enzyme produced includes determining of optimum pH, temperature, and substrate UV-Vis spectrophotometer. Antagonistic test of the chitinase enzyme and endophytic bacterial isolates (isolate K4) Fusarium oxysporum. The results showed that bacterial isolate K4 had with chitinolytic index of 2.45 mm. Electrophoresis results with PCR 16s rRNA gene; the length of the amplified fragment is the position of 1300 bp. By doing the BLAST process in GenBank, the bacterial isolate has 97.93% similarity with Enterobacter cloacae. Then, this endophytic bacteria is called Enterobacter cloacae K4-G. This bacterium produced chitinase enzyme reaching maximum chitinase activity at the 38 hours with an activity of 0.0312 U/mL. The chitinase characterization results of E. cloacae K4-G showed that the optimum conditions were reached at at pH 6, temperature 45 ᵒC, and 2.5% substrate with a chitinase activity value of 0.2467 U/mL. Chitinase enzyme and bacteria Enterobacter cloacae K4-G can inhibit the growth of the fungus Fusarium oxysporum. Therefore, Chitinase from Enterobacter cloacae K4-G can be used as an antifungal pathogen in plants.
 
 Keywords: Chitinase, endophytic bacteria, Enterobacter cloacae

Anti-nemic potential of Laurencia papillosa and Dilophys fasciola biosynthesized nano-extracts against tomato root-knot nematode Meloidogyne incognita

Due to the damaging effects of root-knot nematodes on crops and the dangerous effects of chemical nematicides on both people and the environment in Egypt, the purpose of this study was to assess the power of polysaccharides and polyphenol extracts as well as their nano-forms from marine algae (Laurencia papillosa and Dilophys fasciola) used as eco-friendly alternatives for the control of Meloidogyne incognita. The nano-forms of algal extracts efficiently suppressed M. incognita egg hatching and increased juvenile mortality compared to the control. The tested treatments effectively decreased galls and egg masses of tomato roots compared to the control in the field. Dilophys fasciola extract and its nano-form showed promising nematicidal activity compared to L. papillosa extract. Generally, algal treatments boosted tomato plant defense system against M. incognita by triggering the production of some biochemical constituents such as phenolic compounds, polyphenol oxidase and chitinase enzymes. Consequently, the productivity and quality parameters of tomato fruits significantly increased.