Statistical optimisation of medium components for chitinase production byPaenibacillus sabina strain JD2

Bioprocess development as a sustainable platform for eco-friendly alkaline phosphatase production: an approach towards crab shells waste management

Background

There are substantial environmental and health risks associated with the seafood industry's waste of crab shells. In light of these facts, shellfish waste management is critical for environmental protection against hazardous waste produced from the processing industries. Undoubtedly, improved green production strategies, which are based on the notion of "Green Chemistry," are receiving a lot of attention. Therefore, this investigation shed light on green remediation of the potential hazardous crab shell waste for eco-friendly production of bacterial alkaline phosphatase (ALP) through bioprocessing development strategies.

Results

It was discovered that by utilizing sequential statistical experimental designs, commencing with Plackett–Burman design and ending with spherical central composite design, and then followed by pH-uncontrolled cultivation conditions in a 7 L bench-top bioreactor, an innovative medium formulation could be developed that boosted ALP production from Bacillus licheniformis strain ALP3 to 212 U L⁻¹. The highest yield of ALP was obtained after 22 h of incubation time with yield coefficient Y_p/s of 795 U g⁻¹, which was 4.35-fold higher than those obtained in the shake-flask system. ALP activity has a substantial impact on the volatilization of crab shell particles, as shown by the results of several analytical techniques such as atomic absorption spectrometry, TGA, DSC, EDS, FTIR, and XRD.

Conclusions

We highlighted in the current study that the biovalorization of crab shell waste and the production of cost-effective ALP were being combined and that this was accomplished via the use of a new and innovative medium formulation design for seafood waste management as well as scaling up production of ALP on the bench-top scale.

Cloning, expression, purification and characterization of chitin deacetylase extremozyme from halophilic Bacillus aryabhattai B8W22

Chitin deacetylase (CDA) (EC 3.5.1.41) is a hydrolytic enzyme that belongs to carbohydrate esterase family 4 as per the CAZY database. The CDA enzyme deacetylates chitin into chitosan. As the marine ecosystem is a rich source of chitin, it would also hold the unexplored extremophiles. In this study, an organism was isolated from 40 m sea sediment under halophilic condition and identified as Bacillus aryabhattai B8W22 by 16S rRNA sequencing. The CDA gene from the isolate was cloned and overexpressed in E. coli Rosetta pLysS and purified using a Ni-NTA affinity chromatography. The enzyme was found active on both ethylene glycol chitin (EGC) and chitooligosaccharides (COS). The enzyme characterization study revealed, maximum enzyme velocity at one hour, optimum pH at 7 with 50 mM Tris-HCl buffer, optimum reaction temperature of 30 ºC in standard assay conditions. The co-factor screening affirmed enhancement in the enzyme activity by 142.43 ± 7.13% and 146.88 ± 4.09% with substrate EGC and COS, respectively, in the presence of 2 mM Mg2+. This activity was decreased with the inclusion of EDTA and acetate in the assay solutions. The enzyme was found to be halotolerant; the relative activity increased to 116.98 ± 3.87% and 118.70 ± 0.98% with EGC and COS as substrates in the presence of 1 M NaCl. The enzyme also demonstrated thermo-stability, retaining 87.27 ± 2.85% and 94.08 ± 0.92% activity with substrate EGC and COS, respectively, upon treatment at 50 ºC for 24 h. The kinetic parameters K m, V max, and K cat were 3.06E-05 µg mL-1, 3.06E + 01 µM mg-1 min-1 and 3.27E + 04 s-1, respectively, with EGC as the substrate and 7.14E-07 µg mL-1, 7.14E + 01 µM mg-1 min-1 and 1.40E + 06 s-1, respectively, with COS as the substrate. The enzyme was found to be following Michaelis-Menten kinetics with both the polymeric and oligomeric substrates. In recent years, enzymatic conversion of chitosan is gaining importance due to its known pattern of deacetylation and reproducibility. Thus, this BaCDA extremozyme could be used for industrial production of chitosan polymer as well as chitosan oligosaccharides for biomedical application.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13205-021-03073-3.

Statistical Optimization for Coproduction of Chitinase and Beta 1, 4-Endoglucanase by Chitinolytic Paenibacillus elgii PB1 Having Antifungal Activity

A bacterial strain PB1 with antagonistic activity against pathogenic fungi was isolated from marine soil and was identified as Paenibacillus elgii based on phenotypic and genotypic characterization. The isolate showed good antifungal activity against "Aspergillus niger (MTCC 282), Trichophyton rubrum (MTCC 791), Microsporum gypseum (MTCC 2819), Candida albicans (MTCC 227), and Saccharomyces cerevisiae (MTCC 170)". Chitinase and beta 1, 4-endoglucanase are known for their capability to degrade fungal cell wall, thus we analyzed its productivity in PB1 strain using Plackett-Burman and Central Composite Design. The factors that affect the productivity of chitinase and beta 1, 4-endoglucanase were identified and optimized. A 7.77-fold increase (3.157 to 24.53 ± 1.33 U/mL) in chitinase and 7.422-fold increase (6.476 to 48.066 ± 0.676 U/mL) in beta 1, 4-endoglucanase versus basal medium was achieved. Chitinase and beta 1, 4-endoglucanase produced by Paenibacillus elgii strain PB1 represents the new source for biotechnological, medical, and agricultural applications.

Optimization of media components for chitinase production by chickpea rhizosphere associated Lysinibacillus fusiformis B-CM18

Chitinase producing strain B-CM18 was isolated from chickpea rhizosphere and identified as Lysinibacillus fusiformis B-CM18. It showed in vitro antifungal activity against a wide range of fungal plant pathogens and was found to produce several PGPR activities. Further, a multivariate response surface methodology was used to evaluate the effects of different factors on chitinolytic activity and optimizing enzyme production. A central composite design was employed to achieve the highest chitinase production at optimum values of the process variables, viz., temperature (20-45 °C), sodium chloride (2-7%), starch (0.1-1%) and yeast extract (0.1-1%), added in the minimal medium supplemented with colloidal chitin (1-10%; w:w). The fit of the model (R(2)  = 0.5692) was found to be significant. The production medium to achieve the highest chitinase production (101 U ml(-1) ) was composed of the minimal medium composed of chitin (6.09%), NaCl (4.5%), starch (0.55%) and yeast extract (0.55%) with temperature (32.5 °C). The results show that the optimization strategy led to an increase in chitinase production by 56.1-fold. The molecular mass of the chitinase was estimated to be 20 kDa by anion exchange and gel filtration chromatography. Further, purified chitinase showed strong antifungal activity against test pathogens. Overall, these results may serve as a base line data for enhancing the chitinolytic potential of bacterial antagonists for bio-management of chickpea pathogens.

Bioprocessing data for the production of marine enzymes

This review is a synopsis of different bioprocess engineering approaches adopted for the production of marine enzymes. Three major modes of operation: batch, fed-batch and continuous have been used for production of enzymes (such as protease, chitinase, agarase, peroxidase) mainly from marine bacteria and fungi on a laboratory bioreactor and pilot plant scales. Submerged, immobilized and solid-state processes in batch mode were widely employed. The fed-batch process was also applied in several bioprocesses. Continuous processes with suspended cells as well as with immobilized cells have been used. Investigations in shake flasks were conducted with the prospect of large-scale processing in reactors.

Optimization of medium constituents for improved chitinase production by Paenibacillus sp. D1 using statistical approach

AIMS

Statistical optimization of medium components for improved chitinase production by Paenibacillus sp. D1.

METHODS AND RESULTS

Urea, K(2)HPO(4), chitin and yeast extract were identified as significant components influencing chitinase production by Paenibacillus sp. D1 using Plackett-Burman method. Response surface methodology (central composite design) was applied for further optimization. The concentrations of medium components for improved chitinase production were as follows (g l(-1)): urea, 0.33; K(2)HPO(4), 1.17; MgSO(4), 0.3; yeast extract, 0.65 and chitin, 3.75. This statistical optimization approach led to the production of 93.2 +/- 0.58 U ml(-1) of chitinase.

CONCLUSIONS

The important factors controlling the production of chitinase by Paenibacillus sp. D1 were identified as urea, K(2)HPO(4), chitin and yeast extract. Statistical approach was found to be very effective in optimizing the medium components in manageable number of experimental runs with overall 2.56-fold increase in chitinase production.

SIGNIFICANCE AND IMPACT OF THE STUDY

The present investigation provides a report on statistical optimization of medium components for improved chitinase production by Paenibacillus sp. D1. Paenibacillus species are gram-positive, spore-forming bacteria with several PGPR and biocontrol potentials. However, only few reports concerning mycolytic enzyme production especially chitinases are available. Chitinase produced by Paenibacillus sp. D1 represents new source for biotechnological and agricultural use.