Chitin Agar Research Articles

Extraction of chitin from edible crab shells of Callinectes sapidus and comparison with market purchased chitin.

Chitin and its derived products have immense economic value due to their vital role in various biological activities as well as biomedical and industrial application. Insects, microorganism and crustaceans are the main supply of chitin but the crustaceans shell like shrimp, krill, lobsters and crabs are the main commercial sources. Chitin content of an individual varies depending on the structures possessing the polymer and the species. In this study edible crabs' shells (Callinectes sapidus) were demineralized and deproteinized resulting in 13.8% (dry weight) chitin recovery from chitin wastes. FTIR and XRD analyses of the experimental crude as well as purified chitins revealed that both were much comparable to the commercially purchased controls. The acid pretreatment ceded 54g of colloidal chitin that resulted in 1080% of the crude chitin. The colloidal chitin was exploited for isolation of eighty five chitinolytic bacterial isolates from different sources. Zone of clearance was displayed by the thirty five isolates (41.17%) succeeding their growth at pH 7 on colloidal chitin agar medium. Maximum chitinolytic activity i.e. 301.55 U/ml was exhibited by isolate JF70 when cultivated in extracted chitin containing both carbon and nitrogen. The study showed wastes of blue crabs can be utilized for extraction of chitin and isolation of chitinolytic bacteria that can be used to degrade chitin waste, resolve environmental pollution as well as industrial purpose.

Antifungal Activity and Properties of Crude Enzymes Produced from Cellulomonas fimi JH-1

In this study, bacteria were isolated from rosemary rhizosphere and chitinolytic activity was detected in 0.2% chitin agar medium. Using 16s rRNA sequencing, the isolated bacteria were identified as Cellulomonas fimi. Chitinase, cellulase, and protease activities were found to increase with incubation time. Chitosanase activity was highest on day 1, and gradually declined thereafter. Crude enzyme of C. fimi was prepared and separated by SDS-PAGE and the expression patterns of enzyme activity for chitinase and chitosanase isozymes was studied. Three chitinase isozymes (36, 55, and 66 kDa) and one chitosanase (39 kDa) were detected SDS-PAGE gel combinded with glycol chitin and glycol chitosan, and these chitinase and chitosanase had different molecular weights. Indole acetic acid (IAA) production by C. fimi was analyzed in nutrient broth (NB) media containing different concentrations of tryptophan. IAA production was found to increase with increasing tryptophan concentration. Siderophore production by C. fimi was analyzed in colloidal chitin medium for 0, 1, 3, 5, and 7 d. The production of siderophore increased for 5 d and gradually decreased thereafter. The antifungal activities of C. fimi against G. zeae, F. solani, B. cinerea, F. oxysporum, C. cucumerinum, R. solani, and C. acutatum were investigated in potato dextrose broth medium containing chitin. C. fimi showed the highest antifungal activity against G. zeae.

Formation of recombinant bifunctional fusion protein: A newer approach to combine the activities of two enzymes in a single protein.

The tissue of insects, pests, and fungi has a chitin layer followed by protein in the cell membrane. The complete biodegradation of chitin and protein-present in the waste requires the action of two enzymes, namely chitinase, and protease. Combining chitinase and protease in a single protein/enzyme will serve as a bifunctional enzyme that can efficiently degrade the chitin and protein-rich biomass. The present study was aimed to fuse these two enzymes to produce a single protein and study the kinetics of the recombinant fusion protein. A chitinase and alkaline protease genes were isolated, cloned, and expressed successfully as a fusion product in heterologous host Escherichia coli. The two native genes were successfully fused in E.coli by using flexible glycine-serine (G4S)2 linker (GGGGS, GS linker). The recombinant fusion protein in E.coli showed hydrolyzed chitin and protein on chitin and bovine serum albumin agar plates confirming the successful cloning and expression of chitinase and protease enzymes in a single fusion protein. The common pUC18-T7 mini vector with the ompA signal sequence helps the extracellular expression of fusion protein efficiently. The native gel electrophoresis revealed a molecular mass of purified protein as 92.0 kDa. The fusion protein's maximal chitinase and protease activity occurred at pH 5.0 and 8.0 and 30 0C, respectively resembling the individual enzymes'. In the kinetic studies of the fusion protein, it was observed that the presence of metal ions such as Cu2+, Na2+, and Ca2+; significantly enhanced the enzyme activities while organic solvents oxidants and chemicals have drastically affected the activities of both the enzymes in the fusion protein. No such fusion protein has been produced in a heterologous host yet. The reports on fusion protein with biomass-degrading capacity are also scarce. This is probably the first report of a bifunctional chitinase/protease expressed in E. coli.

Biocontrol Activity, Mode of Action, and Colonization of Aureobasidium pullulans Dmg 30 DEP on Controlling Early Blight Disease on Tomato Plant

We investigated the biocontrol activity of A. pullulans Dmg 30 DEP against Alternaria solani causal agent of early blight. Biocontrol activity was tested by the in vivo and ad planta. Biocontrol activity were tested by investigating the antibiosis capabilities with dual culture method, paper dish assay, two-compartment petri dish assay, and trapping and identification of volatile organic compounds (VOCs) with GC-MS. Lysis activity was examined by observing the clear zone formed by growing yeast on chitin agar and skim milk agar. The ability of hyperparasitism was assessed by the agar block method, and observed by light microscopy and scanning electron microscopy (SEM). The results showed that A. pullulans Dmg 30 DEP plays a role in the suppression of early blight disease at 106 cells/ml and 107 cells/ml yeast cell density. The mechanism involved in biocontrol activity is the production of VOCs, the production of chitinase and protease enzymes, the production of siderophore and hyperparasitism. The result shows that A. pullulans Dmg 30 DEP was colonizing the tomato leaves following the areole.

Chitinase Activity by Chitin Degrading Strain (Bacillus Salmalaya) in Shrimp Waste

Introduction: Chitin degradation by chitinase enzyme can be used on a large scale for bioremediation of seafood waste and is environmentally friendly. Objective: The main aim of this study was to screen the potential of the strain as a chitin degrading agent. Methods: In this present study, the cell-free supernatant of Bacillus salmalaya was determined for its protein concentration. Bacillus salmalaya139SI was isolated from agricultural soil and it was identified by staining technique and colony morphology. The production of chitinase by Bacillus salmalaya139SI was optimized under different concentrations of substrate, pH and temperature. Results: Strain 139SI exhibited strong hemolytic activity and the crude protein concentration of Bacillus salmalaya was 84.09mg/ mL with OD value 0.462. Strain 139SI were also screened on colloidal chitin agar medium supplemented with mineral salt. Chikinase production was determined by clear zones of hydrolysis produced after 7 days of incubation at 37°C. The maximum chitinase production was observed in Brain Heart Infusion broth supplemented with 1.0% colloidal chitin at pH 7 and temperature 35°C after four days of incubation. Chitinase activity was observed when high concentrations of crude extract of 139SI able to degrade shrimp shell by showing the degradation zone at day 4. Conclusion: From the results, we concluded that the Bacillus salmalayahas potential to be a biofunctional chitinase that could degrade complex polysaccharides present in the organic wastes and applicable in cleaning the environment.

Biological control of fungal pathogens of tomato (Lycopersicon esculentum) by chitinolytic bacterial strains

The need to increase food production and to reduce the pollution caused by synthetic chemicals has led to a search for biocontrol agents against plant pathogens. In the present study, a total of 37 chitinolytic bacteria were isolated from the rhizospheric soil of tomatoes using a chitin agar medium. In vitro bacterial isolates, that is, TD9, TD11, TD15, and TD24 showed strong antagonistic and enzymatic activities against Rhizoctonia (8%-55%), Fusarium (31%-48%), Colletotrichum (24%-49%), and Aspergillus on a dual culture plate and enzyme assay. Furthermore, these putative antagonistic bacterial isolates were identified as Pantoea agglomerans (TD9), Bacillus subtilis (TD11), Bacillus cereus (TD15 and TD24) using 16S rRNA sequence analysis. Additionally, in culture filtrate in vivo assay, the isolates TD11 and TD15 inhibited the growth of Rhizoctonia solani about 40% and Fusarium oxysporum about 80%. However,in the pot trials, these two bacterial isolates (TD11 and TD15) considerably suppressed the disease rate in tomatoes caused by Fusarium and Rhizoctonia fungal species. Moreover, it was concluded that B. subtilis (TD11) was found to be the most promising putative biocontrol agent, inhibiting the fungal diseases of tomatoes by 50% and showing versatile antagonistic potential.

Antifungal Activity of Chitinase- and Chitosanase-Producing Rhizosphere Bacteria

In this study, the chitinolytic activity of rhizosphere bacteria was detected on a 0.2% colloidal chitin agar medium. A zone of clearance indicating chitinase activity was observed around the discs in Paenarthrobacter nicotinovorans, Chitinophaga oryziterrae, and Bacillus stratosphericus. For the determination of the pH stability of the bacterial chitinase, the three bacterial isolates were incubated at different pH ranges from pH 3~7. All three isolates showed the highest chitinase activity at pH 4. Five chitinase isozymes (66, 57, 49, 45 and 36 kDa) and one chitosanase (40 kDa) were detected in P. nicotinovorans. While C. oryziterrae did not. P. nicotinovorans showed the highest antifungal activity on PDA against Botrytis cinerea and Colletotirchum higginisianum. However, in the potato dextrose broth, C. oryziterrae showed the highest antifungal activity based on the fungal mycelial dry weight measurement. These results indicate that three chitinase-producing rhizosphere bacteria can potentially be used as biocontrol agents in agricultural applications.

Screening of chitinase-producing rhizosphere actinomycetes and their genetic diversity

Abstract. Wahyudi AT, Fitriansyah NG, Amri MF, Priyanto JA, Nawangsih AA. 2021. Screening of chitinase-producing rhizosphere actinomycetes and their genetic diversity. Biodiversitas 22: 4186-4192. Soil microbial community, especially rhizosphere actinomycetes, plays an important role in protecting plants from phytopathogenic fungi by producing various agroactive compounds, including mycolytic enzymes particularly chitinase. The objective of this study was to investigate chitinase activity and analyze the diversity of family 19 chitinase genes of actinomycetes isolated from maize and soybean rhizosphere. Of fivety actinimycetes, Seventeen isolates exhibited chitinolytic activities and formed a hydrolytic zone around the colony with chitinolytic index ranging from 0.49±0.01 to 2.15±0.69, qualitatively tested in 0.3% chitin agar medium. Six selected isolates (ARJ 36, ARJ 81, ARJ 15, ARK 17, ARK 143, ARK 103) showed chitinase activities ranging from 0.157±0.04 to 0.440±0.09 U/mL, based on chitinolytic index. The production of chitinase was confirmed by the presence of family 19 chitinase encoding genes from Streptomyces sp. Some conserved regions and essential amino acid residues were also detected. This study suggests that chitinolytic actinomycetes isolated from maize and soybean rhizosphere can be studied further as biological control candidates for controlling phytopathogenic fungi.

Characterization of the gene encoding chitinase enzyme from bacillus isolates insulated from some locations in Southeast Sulawesi

This study aimed to determine the isolates of local Bacillus that have potential chitinolytic activity and to know the characteristic of the gene encoding chitinase enzyme from local Bacillus isolates from Southeast Sulawesi that were selected to have chitinolytic activity. Selection of chitinolytic bacteria based on bacterial ability to form clear zone on chitin agar medium which was grew by spread method and incubated for 4 days. From 5 test isolates used, one isolate which had chitinolytic activity was isolate Bacillus sp. Rh 3.8. The amplification of the gene encoding chitinase enzyme selected bacterial isolates was done by PCR (Polymerase Chain Reaction) technique using Chitbac F and Chitbac R primers. Sequence analysis was conducted by BLASTn, mapping of restriction enzyme using Bioedit software, analysis of amino acid using expasy software, analysis of hydrophobicity using Bioedit software, phylogenetic tree construction using MEGA software. The results showed that the characters of the gene encoding chitinase enzyme was a gene measuring 804 bp. Based on BLASTn analysis, the gene has 100% similarity with Bacillus thuringiensis SCG0402 (CP017577). The gene has 9 restriction enzyme cutting sites. Based on hydrophobicity analysis shows that the amino acid sequence of chitinase enzyme is dominant exist on hydrophilic region. The results of phylogenetic tree construction show isolates of the Bacillus sp. Rh 3.8 is a group with Bacillus thuringiensis so this strain is a species of Bacillus thuringiensis.

Novel chitinolytic bacteria from the shrimp shell processing waste

Abstract. Masri M, Sukmawaty E, Aditia L. 2021. Novel chitinolytic bacteria from the shrimp shell processing waste. Biodiversitas 22: 2672-2681. Chitinase is an enzyme that hydrolyzes chitin (?-1,4 Nsetyl-D-glucosamine polymer). Several types of microorganisms produce chitinase that contributes to basic science and application. The role of chitinase enzyme is widely utilized in various fields, such as health as an anti-tumor agent and agriculture as biological control agents in plant disease caused by fungus. The purpose of this study was to isolate novel chitinolytic bacteria from shrimp shell waste in Makassar, Indonesia, using the scatter plate method on chitin agar selective media incubated at 37°C for 3 days. The clear zone formation around the colony was marked as an indicator of chitinase activity performed by the certain isolate. Selection was carried out by recycling all isolates on chitin agar media, which were incubated at 37°C for 3 days and measured the chitinolytic index. Two of ten isolates produced the highest chitinolytic index, namely, KLA-2 (45) and KLA-4 (15) isolates. The molecular identification results showed that the KLA-2 and KLA-4 isolates were Lysinibacillus fusiformis strain WH22 and Brevibacillus reuszeri strain CMB-15, respectively. Therefore, novel chitinolytic bacteria that can produce chitinase enzyme from shrimp shell waste are L. fusiformis and B. reuszeri

In Vitro Study of Action Mode of Rhodotorula minuta Dmg 16 BEP as Biocontrol Agents on Alternaria solani

Rhodotorula sp. is widely known as a biocontrol agent and is reported effective in controlling several diseases on crops. Rhodotorula minuta Dmg 16 BEP is an antagonist yeast from Indonesia which was effective in controlling various plant diseases. The objective of this research was to study the in vitro mode of action of R. minuta Dmg 16 BEP against Alternaria solani. The antibiosis ability of R. minuta Dmg 16 BEP to A. solani might be based on the activity of volatile compounds and not from its metabolites products. The growth of A. solani in paper disk assay and dual culture tests were not inhibited nor inhibitory zones developed, whereas the inverse petridish test showed the growth inhibition of A. solani. The results of the chitinolytic activity test on chitin agar and proteolytic on skim milk agar showed that no clear zone was formed. R. minuta has a strong hyperparasitic ability according to the slide culture test as the yeast cells surrounded A. solani hyphae and caused damage to some parts of hyphae.

Soil Chitinolytic Bacteria from Jambi Province to Produce Antifungal of Plant Pathogens

Chitinolytic bacteria are bacteria that have chitinolytic activity, which is able to hydrolysis the composition of chitin which composes many fungal cell walls. Chitinolytic bacteria are currently more widely used because of their ability as a biological control agent to the pathogenic fungi especially in horticultural and plantation crops. This research was conducted with the aim of obtaining isolates of chitinolytic bacteria that were able to inhibit the growth of plant pathogenic fungi in Vitro on chitin agar media. Fusarium oxysporum, Sclerotium rolfsii, and Rhizoctonia solanii are used in the inhibition test of chitinolytic bacteria. Bacteria were isolated and screened from the soil of Bukit Dua Belas National Park and Oil Palm Plantations in Jambi using 0.3% chitin agar media. The results showed that two of 10 bacterial isolates were able to produce inhibition zones to the growth of hyphae of pathogenic fungi on potato dextrose agar (PDA) media. TB04-13 isolate was able to produce the largest inhibition in F. oxysporum and R. solanii about 42% and 42.05% respectively, while TB04-15 isolate produced the biggest inhibition in S. Rolfsii ranged to 25.50%. Based on the chitinolytic index (CI) values, isolates TB04-13 and TB04-15 produced CI values ​​of 1.60 and 0.63, respectively. The morphological characteristics and Gram staining of both TB04-13 and TB04-15 chitinolytic isolates are included in rod-shaped and Gram-positive bacteria. Both of these isolates can be used as antifungal-producing candidates for plant pathogenic fungi in Indonesia.

A biological study of chitinase produced by clinical isolates of Pseudomonas aeruginosa and detection of ChiA responsible gene

All isolates in this study were diagnosed as P. aeroginosa according to the 16srRNA gene. Only two isolates were produced chitinase on chitin agar medium and were positive to the chiA gene. Most of the isolates exhibited high sensitivity (95%) and (90%) to Imipenem and Carbenicillin, respectively, and the resistance to Amoxicillin +Clavulanic acid was shown (80%), while revealed a variable degree in their response to others antibiotics. The crude extract activity and specific activity for extracted chitinase enzymes were 33 U/ml and 18.644U/mg, respectively. The enzyme was purified by different steps include: precipitating with saturation 70% of ammonium sulfate and then applied on ion-exchange chromatography using DEAE- cellulose column and then employ the Sephadex G-200 column for gel filtration chromatography. The purification fold and yield was 28.5%. The molecular weight of the purified enzyme was determined by SDS-PAGE method, and it appeared at 50 kDa. The results of the MTT assay showed that the chitinase has a cytotoxic effect on cancer liver cell lines at a concentration of 100 µg /ml and increased gradually at a concentration of 600 µg /ml, while it showed no or less cytotoxic effect on normal embryonic liver cell line (WRL-68). Chitinase enzyme appeared a higher antibacterial activity at concentration 600 µg/ml and a lower activity at concentration 400 towards clinical isolates of S. aurous and E. coli. The study of histopathological effects was exhibited little morphological changes on cells of liver tissues.

Isolation and screening of microorganisms for chitosan production

Chitosan is a cationic linear biopolymer that is produced by deacetylation of chitin by chitin deacetylase. This enzyme hydrolyses acetamido groups of N-acetyl glucosamine in chitin. Chitosan has immense potential especially in the field of agriculture, food and pharmaceuticals. In most of the countries, commercial exploitation of chitosan is predominantly done by conversion of chitin to chitosan by treating shellfish waste with alkali. The biological methods for extraction of chitosan were used as alternative for chemical methods. In the present study, 18 morphologically different fungal isolates, 17 bacteria and 3 actinomycete were isolated from soil and water samples. Out of these 38 strains, six isolates of fungi, two bacterial isolates and one actinomycete showed positive results by production of yellow color in the chitin agar media supplemented with p-nitroacetanilide as indicator.

Isolation and Molecular Identification of Chitinolytic Bacteria from Ronto

Ronto is a traditional food from South Kalimantan made of processed rebon shrimp. The production of Ronto relies on the fermentation process done by various types of microorganisms, especially bacteria. With shrimp as the main ingredient, Ronto has a high salt concentration and low pH level. Therefore, there is a potential in the exploration of chitinolytic bacteria with specific characteristics in Ronto. This study aimed to isolate and identify chitinolytic bacteria in Ronto. Ronto that was used in this experiment had a pH of 5. The isolation of chitinolytic bacteria using chitin agar obtained 10 isolates, namely RNT1, RNT2, RNT4, RNT5, RNT6, RNT7, RNT8, RNT9, RNT10, and RNT11. The chitinolytic index of these isolates ranged from 1.1 to 2.8. The highest chitinolytic index was shown by isolate RNT8. Molecular identification using a partial 16s rRNA gene shows that all isolates were similar to Bacillus sp.

Evaluation of enzymatic activity and identification of potent proteolytic and chitinolytic bacteria isolated from crab shell waste

Abstract. Dliyauddin M, Ardyati T, Suharjono. 2020. Evaluation of enzymatic activity and Identification of Potent Proteolytic and Chitinolytic Bacteria Isolated from Crab Shell Waste. Biodiversitas 21: 211-218. Proteolytic and chitinolytic bacteria are needed to degrade protein-chitin fibers in crab shell waste. These bacteria are important for enhancing the degradation rate of crab shell waste in the environment. This study aims to study the enzymatic activity and identify potent proteolytic and chitinolytic bacteria based on 16S rDNA sequences. The bacteria were isolated from crab shell waste using skim milk agar and colloidal chitin agar for proteolytic and chitinolytic bacteria, respectively. The bacterial isolates were screened based on their protease and chitinase activity using casein and chitin as substrates, respectively. The selected isolates were identified based on 16S rDNA sequences similarity. A total of 20 proteolytic and 22 chitinolytic bacteria were successfully isolated from the samples. The isolate of AP9, AP5, and BP14 had a high protease activity. However, only BP14 and CK20 showed a high chitinase activity. The isolate of AP9 was identified as Bacillus subtilis, AP5, and CK20 were identified as Bacillus licheniformis, and BP14 was identified as Bacillus cereus. AP5 dan CK20 were classified as non-pathogenic isolates.

Additive Effect of Chitinase Genes in Transconjugants of Entomopathogens Bacillus thuringiensis to Improve Biological Control of Tuta absoluta

This study aimed to evaluate the toxicity of Bacillus thuringiensis (Bt) transconjugants harboring chitinase genes against larval stage of Tuta absoluta . Bacillus licheniformisand Serratia marcescens were used as donors against Bt . Bacillus transconjugants were evaluated for chitinase activity depending on hydrolysis zone appeared on chitin agar medium. Parental strains and their recombinants significantly reduced the number of survived larvae if compared with untreated larvae. Mortality rate was gradually increased to reached a maximum ratio after six days of treatments. Most bioinsecticides including parental strains and their transconjugants significantly losses larval body weight daily if compared with untreated larvae.Bioinsecticides, as well as, bioinsecticide concentrations and the interaction between both factors showed negative significant effect on larval body weight at most time intervals of larval age.In addition, Bt recombinants , as well as, their parental strains has exhibited a great potential effect for controlling and suppress the feeding of larval stage on the host plants.

Expression of Serratia and Pseudomonas Chitinase Genes in Rhizobium Via Horizontal Gene Transfer

This study aimed to transfer chitinase genes into Rhizobium leguminosarum bv. vicia in order to enhance the defense of faba bean plants against soil pathogens, in addition to , improving symbiotic nitrogen fixation, as well. Toward this target, 12 transconjugants resulted from conjugation between Pseudomonas flurocescens and Serratia marcescence as a donors against four strains of Rhizobium leguminosarum. The donar strains were tested for chitinolytic activity depending on chitin hydrolysis zone appeared on chitin agar medium. Six out of eight matings between Pseudomonas and Serratia against Rhizobium were successeded. Some recombinants expressed significant amount of IAA production in both complete and minimal media. Some of Rhizobium transcojugants showed significant performance for chitinase activity above the mid-parent. Cell culture and cell – free filterate of some Rhizobium transconjugants showed higher antagonistic activity against Rhizoctonia solani in relation to the mid-parent, because they were able to produce higher amounts of antifungal metabolites. These transcojugants may inhibit the growth of various soil-born pathogens with a higher efficiency than their parents.

Efektivitas enzim kasar kitinase dari jamur Trichoderma viride yang diiradiasi oleh sinar gamma terhadap degradasi cangkang telur nematoda Haemonchus contortus pada ternak domba

The aim of this study was to determine increasing of chitinase crude enzyme activity produced by Trichoderma viride at different gamma irradiation doses and to know the degradation on the eggshell of Haemonchus contortus . Eggs of Haemonchus contortus were isolated from sheep feces using buoyant centrifugation method. The qualitative test of chitinase was conducted by inoculating Trichoderma viride irridiated by variation gamma doses control, 250 Gray, 500 Gray, 750 Gray and 1000 Gray on the media of colloidal chitin agar. The quantitative test was conducted by measuring chitinase activity using colorimetric method based on specific enzyme activity and determination of dissolved protein levels. Shell changes were observed microscopically while N-acetyl glucosamine levels and dissolved protein levels were measured using spectrophotometer. Data were analyzed using One Way Analysis of Variance (ANOVA) with significance of the 95% and continued with Duncan’s Multiple Range Test (DMRT test). The results showed that gamma irradiation doses treatment increase of chitinase crude enzyme activity produced by Trichoderma viride . At a dose of 500 Gray, Trichoderma viride had the optimum chitinase specific activity i.e. 0.30 U/mg. Furthermore, chitinase crude enzyme effective to degrade all layers of the eggshell of Haemonchus contortus and the higher the concentration of crude enzyme given, the greater the level of egg damaged.

Entomopathogenic efficacy of the chitinolytic bacteria: Aeromonas hydrophila isolated from Siwa Oasis, Egypt

Thirty-four bacterial isolates were isolated from soil samples collected from the North Western Coast and a water sample collected from brackish water at Siwa Oasis, Matrouh Governorate, Egypt. Only six isolates showed chitinase activity when screened on colloidal chitin agar medium. The highest chitinolytic activity was achieved by a bacterial isolate labeled as A.S. This isolate was identified as Aeromonas hydrophila based on analysis of 16S rRNA gene sequence and morphological, physiological, and biochemical characteristics. Optimization of the cultural conditions for maximum chitinase production by A. hydrophila revealed that the highest level of chitinase was recorded when the bacterium was grown in malt nitrogen-based medium containing 1% colloidal chitin at pH7 for 48 h incubation at 30 °C. Crude chitinase from isolate A. hydrophila was evaluated against first instar larvae of the greater wax moth; Galleria mellonella L. (Lepidoptera: Pyralidae) at different concentrations of 0, 185, 205, 235, 265, 295 U/mg protein. It increased larval and pupal mortality rates in a concentration-dependent manner. The tested crude chitinase significantly induced a decrease in adults’ emergence rate and their fecundity.