Aims: The objectives of this study were to screen chitinolytic bacteria isolated from soil of Taman Nasional Bukit Duabelas, Jambi, Indonesia. Isolates were selected based on chitinolytic index and antagonism activity of Colletotrichum capsici. Chitinase enzyme from selected isolates was investigated for growth inhibition of C. capsici. Methodology and results: Two chitinolytic bacteria were selected based on their ability to degrade colloidal chitin and inhibit of the growth of C. capsici. Those isolates were KAHN 15.12 and SAHA 12.12, identified as Serratia marcescens and Bacillus thuringiensis respectively based on 16S rRNA gene. The chitinase maximum specific activity of isolate KAHN 15.12 was 52.03 U/mg after 36 h of incubation and SAHA 12.12 was 45.67 U/mg after 24 h of incubation. The enzyme was precipitated by ammonium sulfate 40% and 60% respectively for KAHN 15.12 and SAHA 12.12. The precipitated chitinases were active over a broad range of pH (5 to 10) and temperature (20 to 80 °C). Enzymes were stable in optimum temperature for 180 min. The precipitated of chitinase KAHN 15.12 and SAHA 12.12 had five and two protein bands respectively on SDS-PAGE gel. Chitinases exhibited an antifungal activity against C. capsici at concentration of 60 ppm. Conclusion, significance and impact of study: Isolates KAHN 15.12 and SAHA 12.12 were successfully selected by their ability to degrade colloidal chitin and inhibit the growth of C. capsici. The isolates had a broad range of pH and temperature, moreover relatively stable at the optimum temperature. Chitinase was effective as biological control for anthracnose caused by C. capsici in chilli.
Chitinase

No Abstract Available.
Arthrobacter* ; Chitinase*

Aims: Cricula trifenestrata is one of natural insects which has not been domesticated yet, thus called as the wild silkworm. C. trifenestrata is known as a silk producer which has high economic and market value. However, the fungi attack on C. trifenestrata cocoon decreased quality and quantity of silk yarn. Chitinolytic bacteria have a high potential as biological control against pathogenic fungi. This research aimed to isolate, select, characterize, and identify chitinolytic bacteria as pathogenic fungi growth inhibitors on C. trifenestrata cocoon. Methodology and results: Chitinolytic bacteria was isolated from the uninfected and infected cocoon while fungi was isolated from the uninfected cocoon. Inhibition test was conducted by Fokkema method and chitinase activity was measured by Spindler method. A total of 36 chitinolytic bacteria and 10 suspected pathogenic fungi isolates have been isolated. Fungal pathogenicity test showed that isolate CSAJ.2 was suspected as fungal pathogen. In vitro inhibition test indicated that chitinolytic bacteria isolate BSEP.3 could inhibit the growth of pathogenic fungi CSAJ.2 with percentage of inhibition 50%. Isolate BSEP.3 showed highest chitinase activity (5.11 U/mL) at the 15th h. It able to inhibit the growth of pathogenic fungi with percentage of inhibition of 47.5% and 46.25%, respectively. Conclusion, significance and impact of study: Identification of bacteria targeted on 16S rRNA gene showed that isolate BSEP.3 had 98% identity with Bacillus amyloliquefaciens B5 while identification of fungi using ITS region of the rDNA showed that isolate CSAJ.2 had 100% identity with Trichoderma virens TV242. Chitinase crude extract was effective to be used as a biological control agent of T. virens CSAJ.2.
Chitinase ; Biological Control Agents

This study investigated the biochemical changes of abnormal fruiting bodies grown under artificial environmental conditions in P. ostreatus. Abnormal mushroom growth during cultivation damages the production of good quality mushroom. This study showed that different environmental conditions produced morphological changes in the fruiting bodies of P. ostreatus. The fruiting bodies with morphological changes were collected and examined for differences in biochemical properties, enzyme activities, and carbohydrates composition. The enzyme activities assay showed that glucanase and chitinase activities decreased when the temperature was below or above the optimum cultivation temperature for P. ostreatus. The biochemical compositions of the abnormal mushroom were significantly different from the normal fruiting bodies. It was suggested that the changes in the biochemical composition of abnormal mushroom were caused by the unfavorable environmental conditions during mushroom cultivation.
Agaricales ; Carbohydrates ; Chitinase ; Fruit* ; Pleurotus*

The ability of Bacillus subtilis, strain ALICA to produce three mycolytic enzymes (chitinase, β-1,3-glucanase, and protease), was carried out by the chemical standard methods. Bacillus subtilis ALICA was screened based on their antifungal activity in dual plate assay and cell-free culture filtrate (25%) against five different phytopathogenic fungi Alternaria alternata, Macrophomina sp., Colletotrichum gloeosporioides, Botrytis cinerea, and Sclerotium rolfesii. The B. subtilis ALICA detected positive for chitinase, β-1,3-glucanase and protease enzymes. Fungal growth inhibition by both strain ALICA and its cell-free culture filtrate ranged from 51.36% to 86.3% and 38.43% to 68.6%, respectively. Moreover, hyphal morphological changes like damage, broken, swelling, distortions abnormal morphology were observed. Genes expression of protease, β-1,3-glucanase, and lipopeptides (subtilosin and subtilisin) were confirmed their presence in the supernatant of strain ALICA. Our findings indicated that strain ALICA provided a broad spectrum of antifungal activities against various phytopathogenic fungi and may be a potential effective alternative to chemical fungicides.
Alternaria ; Bacillus subtilis* ; Bacillus* ; Botrytis ; Chitinase ; Colletotrichum ; Fungi* ; Lipopeptides ; Prosopis*

Chitin, the second most abundant polysaccharide in nature after cellulose, consist exoskeleton of lower organisms such as fungi, crustaceans and insects except mammals. Recently, several studies evaluated immunologic effects of chitin in vivo and in vitro and revealed new aspects of chitin regulation of innate and adaptive immune responses. It has been shown that exogenous chitin activates macrophages and other innate immune cells and also modulates adaptive type 2 allergic inflammation. These studies further demonstrate that chitin stimulate macrophages by interacting with different cell surface receptors such as macrophage mannose receptor, toll-like receptor 2 (TLR-2), C-type lectin receptor Dectin-1, and leukotriene B4 recepptor (BLT1). On the other hand, a number of chitinase or chitinase-like proteins (C/CLP) are ubiquitously expressed in the airways and intestinal tracts from insects to mammals. In general, these chitinase family proteins confer protective functions to the host against exogenous chitin-containing pathogens. However, substantial body of recent studies also set light on new roles of C/CLP in the development and progression of allergic inflammation and tissue remodeling. In this review, recent findings on the role of chitin and C/CLP in allergic inflammation and tissue remodeling will be highlighted and controversial and unsolved issues in this field of studies will be discussed.
Animals ; Chitin/*immunology ; Chitinase/*immunology ; Glycoproteins/*immunology ; Humans ; Hypersensitivity/*immunology ; Inflammation/*immunology

Ten strains of the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana were evaluated to find the most effective strain for optimization studies. The first criterion tested for strain selection was the mortality (> 50%) of Spodoptera litura larvae after inoculation of the fungus for 4 days. Results on several bioassays revealed that B. bassiana BNBCRC showed the most virulence on mortality S. litura larvae (80% mortality). B. bassiana BNBCRC also showed the highest germination rate (72.22%). However, its conidia yield (7.2 x 10(8) conidia/mL) was lower than those of B. bassiana B 14841 (8.3 x 10(8) conidia/mL) and M. anisopliae M6 (8.2 x 10(8) conidia/mL). The highest accumulative radial growth was obtained from the strain B14841 (37.10 mm/day) while the strain BNBCRC showed moderate radial growth (24.40 mm/day). M. anisopliae M6 possessed the highest protease activity (145.00 mU/mL) while M. anisopliae M8 possessed the highest chitinase activity (20.00 mU/mL) during 96~144 hr cultivation. Amongst these criteria, selection based on virulence and germination rate lead to the selection of B. bassiana BNBCRC. B. bassiana B14841 would be selected if based on growth rate while M. anisopliae M6 and M8 possessed the highest enzyme activities.
Beauveria ; Biological Assay ; Chitinase ; Fungi ; Germination ; Larva ; Metarhizium ; Patient Selection ; Spodoptera ; Spores, Fungal ; Sprains and Strains

Foliar sprays of three plant resistance inducers, including chitosan (CH), potassium sorbate (PS) (C₆H₇kO₂), and potassium bicarbonates (PB) (KHCO₃), were used for resistance inducing against Erysiphe cichoracearum DC (powdery mildew) infecting okra plants. Experiments under green house and field conditions showed that, the powdery mildew disease severity was significantly reduced with all tested treatments of CH, PS, and PB in comparison with untreated control. CH at 0.5% and 0.75% (w/v) plus PS at 1.0% and 2.0% and/or PB at 2.0% or 3.0% recorded as the most effective treatments. Moreover, the highest values of vegetative studies and yield were observed with such treatments. CH and potassium salts treatments reflected many compounds of defense singles which leading to the activation power defense system in okra plant. The highest records of reduction in powdery mildew were accompanied with increasing in total phenolic, protein content and increased the activity of polyphenol oxidase, peroxidase, chitinase, and β-1,3-glucanase in okra plants. Meanwhile, single treatments of CH, PS, and PB at high concentration (0.75%, 2.0%, and/or 3.0%) caused considerable effects. Therefore, application of CH and potassium salts as natural and chemical inducers by foliar methods can be used to control of powdery mildew disease at early stages of growth and led to a maximum fruit yield in okra plants.
Abelmoschus* ; Bicarbonates ; Catechol Oxidase ; Chitinase ; Chitosan* ; Fruit ; Peroxidase ; Phenol ; Plants* ; Potassium* ; Salts* ; Sorbic Acid

The fruit body of Ramaria botrytis DGUM 29001 was used to determine enzyme activities of fruit body. The specific activity of laccase was the highest(6.5 unit/mg.protein) and that of alpha-amylase and xylanase was relatively high. However, little or no enzyme activity of beta-glucosidase, CMCase, exo-beta-1,4-glucanase, chitinase, lipase and protease was found.
alpha-Amylases ; beta-Glucosidase ; Botrytis* ; Chitinase ; Fruit* ; Glucan 1,4-beta-Glucosidase ; Laccase ; Lipase

Four Trichoderma strains (CH2, SH16, PQ34, and TN42) were isolated from soil samples collected from Quang Tri and Thua Thien Hue provinces in Vietnam. The strains exhibited high chitinolytic secretion. Strain PQ34 formed the largest zone of chitinase-mediated clearance (> 4 cm in diameter) in agar containing 1% (w/v) colloidal chitin. Analysis of the internal transcribed spacer regions of these strains indicated that they were Trichoderma asperellum. The molecular weights of the chitinases were approximately 42 kDa. Chitinase genes (chi42) of T. asperellum strains TN42, CH2, SH16, and PQ34 were 98~99% homologous to the ech42 gene of T. harzianum CB-Pin-01 (accession No. DQ166036). The deduced amino acid sequences of both T. asperellum strains SH16 and TN42 shared 100% similarity.
Agar ; Amino Acid Sequence ; Chitin ; Chitinase ; Colloids ; Molecular Weight ; Soil ; Sprains and Strains ; Trichoderma ; Vietnam