Biosynthesis of raw starch degradingβ-cyclodextrin glycosyltransferase by immobilized cells of Bacillus licheniformis using potato wastewater

The study was sought to enhance the synthesis of thermal stableβ-cyclodextrin glycosyltransferase(β-CGTase)using potato wastewater as a low-cost medium and assess the degree to which it is efficient for industrial production ofβ-cyclodextrin(β-CD)from raw potato starch.Thermophilic bacteria producingβ-CGTase was isolated from Saudi Arabia and the promising strain was identified as Bacillus licheniformis using phylogenetic analysis of the 16S rRNA gene.Alginate-encapsulated cultures exhibited twice-fold ofβ-CGTase production more than free cells.Scanning electron microscopy(SEM)of polymeric capsules indicated the potential for a longer shelf-life,which promotes the restoration of activity in bacterial cells across semi-continuous fermentation ofβ-CGTase production for 252 h.The optimal conditions forβ-CGTase synthesis using potato wastewater medium were at 36 h,pH of 8.0,and 50°C with 0.4%potato starch and 0.6%yeast extract as carbon and nitrogen sources,respectively.The purified enzyme showed a specific activity of 63.90 U/mg with a molecular weight of∼84.6 kDa as determined by SDS-PAGE analysis.The high enzyme activity was observed up to 60°C,and complete stability was achieved at 75°C.High levels of activity and stability were shown at pH 8.0,and the pH range from 7.0–10.0,respectively.The enzyme has an appreciable affinity for raw potato starch with a Km of 5.7×10−6 M and a Vmax of 87.71μmoL/mL/min.β-CD production was effective against 25 U/g of raw potato starch.The outcomes demonstrated its feasibility to develop a fermentation process by integrating the cost-effective production ofβ-CGTase having distinctive properties forβ-CD production with ecofriendly utilization of potato wastewater.

Effect of preozonation on improvement of settleability of solid in highly concentrated organic wastewater of Japanese wheat and sweet potato spirit-distillery

Solid-liquid separation of the wastewater is very difficult because of high viscosity and high SS concentration. In this study, the effectiveness of preozonation on improving the settleability of the solids in wheat and sweet potato wastewaters was investigated using a bench-scale system and pilot treatment system respectively. Results showed that solid-liquid separation in the wheat wastewater was greatly improved by the decanter in the system(SS reduction from 24100 mg/L to 100 mg/L). However, preozonation practice did not show a significant effect on solid-liquid separation of the sweet potato wastewater. Effect of preozonation on solid-liquid separation between wheat and sweet potato wastewater showed different.

Effects of Bacillus amyloliquefaciens Biofertilizer on Tea Yield and Quality

[Objective] This study was aimed to explore the effects of Bacil us amy-loliquefaciens biofertilizer on tea yield and quality. [Method] The field plot experiment was conducted with the biofertilizer treatments and control to investigate 100-bud weight and main biochemical components. [Result] The treatments by Bacil us amy-loliquefaciens biofertilizer, which was fermented using sweet potato starch wastewa-ter （SPSW） as culture medium, improved 100-bud weight and tea quality significant-ly under the concentration of 0.8×108, 1.6×108 and 3.2×108 cfu/ml with the dose of 1 L/m2 for 4 times. At the optimum concentration of 1.6 ×108 cfu/ml, the biofertilizer treatment increased the 100-bud weight by 22.3%, water extracting materials by 21.9%, amino acids content by 8.83%, tea polyphenol content by 9.76%, and de-creased theine content by 8.32%, respectively. Compared with the control, there was no significant difference between the SPSW treatment and the control. [Con-clusion] The production of the B. amyloliquefaciens biofertilizer could consume SP-SW, and the application of the biofertilizer could improved the tea yield and quality, which provided references for the development of ecological agriculture.

Effects of Bacillus amyloliquefaciens Biofertilizer on Brassica juncea var. multiceps Growth and N_2O Emission from Soil

In this study, Bacil us amyloliquefaciens A3 was continual y incubated in shake fIasks contalning wastewater from sweet potato starch production as an ef-fective biofertiIizer for cuItivation of Brassica juncea var. multiceps（XueIihong）. Based on pot experiments in the greenhouse, the effects of chemical fertiIizers （CN）, biofertiIizer （BF）, inactivated broth （BI）, starch wastewater （SW） and the combination of biofertiIizer and chemical fertiIizer （BC） on the yield, NO3- content and NO2- con-tent of XueIihong, soiI physicochemical properties and N2O emission were investi-gated. The resuIts showed that the yield of XueIihong in BC and CN treatments was improved by five times compared with CK; BF and SW treatments had insignifi-cant impact on the yield of XueIihong. Compared with CN treatment, BCL treatment exhibited simiIar improving effects on the yield of XueIihong, in which NO3- content of XueIihong and soiI was reduced by 16.4%-73.6% and 22%-29%, which reduced the risk of nitrogen eIuviations in soiI; average N2O fIux （FPV30） in BCL treatment was reduced by 58.3%-73.1% compared with CN treatment. In concIusion, B. amy-loliquefaciens is a feasibIe Iow-cost biofertiIizer for sustalnabIe vegetabIe farming with a great potential for starch wastewater utiIization.

New application of microbial fuel cell-based biosensor for monitoring the quality of actual potato chips’processing wastewater

In this study,a dual-chamber microbial fuel cell(MFC)fed with actual potato chips’processing wastewater(PCPW)was tested as a biosensor.The performance of MFC-based biosensor was evaluated in terms of the current measurement range,toxicity detection and sensitivity,and the operational stability.The results revealed that the MFC can simply be converted to an online biosensor unit to detect the harmful effect of suspended solids and acidic content in the actual PCPW on the anodic attached biofilm and the values of the generated current as well.A notable decrease in the current values was observed indicating the adverse effects of the harmful matters in the PCPW fed to the biosensor unit.The results proposed a competition between the harmful components and the favorable substrate in binding to the redox complex.An excellent fitting was obtained between the experimental and predicted results by I_(Km) model with determination coefficient(R^(2))and mean-square-error values of 0.927 and 0.363,respectively.Additionally,a new approach was developed based on direct measurement of actual field data to replace the conventional statistical methods.