Glucoamylase from a Newly Isolated Aspergillus niger FME: Detergent-Mediated Production, Purification, and Characterization

Satheesh Kumar Gudi,최용락,Chandrasekhar Gurramkonda,Gulam Rather,Muniramanna Gari Subohsh Chandra,Usha Kiranmayi Mangamuri,Shdhakar Podha 한국응용생명화학회 2013 Applied Biological Chemistry (Appl Biol Chem) Vol.56 No.4

Glucoamylase (EC 3.2.1.3) is an important group of enzymes in starch processing, also referred to as amyloglucosidases,which are exo-acting amylases that release glucose from the nonreducing end of starch and related oligosaccharides. The glucoamylase newly isolated from the Aspergillus niger FME)was reported for the first time. This enzyme was produced by detergent-mediated release and purified to ~9.11 fold using Sephadex-G 100 and ion-exchange chromatography. Molecular mass of the glucoamylase was ~36 kDa as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The product of starch hydrolysis, analysed by thin-layer chromatography, showed the presence of glucose. The optimum pH and temperature for glucoamylase activity was 5.0 and 45oC,respectively. The Km and Vmax values of the enzyme were also determined using soluble starch as substrate as 94 μg/mL and 39.02 U/mg, respectively. Moreover, glucoamylase was slightly activated by presence of Na and K ions and 10–20% inhibition was observed in presence of Zn2+, Sn2+, Mg2+, Ni2+, Mn2+, and almost 80% with Cu2+ ions, whereas the presence of ethylene diamine tetra acetic acid (EDTA) did not show significant inhibition. Glucoamylase, also assayed for surfactant property, shows significant surfactant tolerance at high concentrations of detergent and can retain 90% of its activity. Finally, secondary structure analysis of glucoamylase by circular dichroism spectroscopy showed the presence of 48% α-helix, 11% β-sheet, and 41%random structure.

Evaluation of efficiency of manual polishing over autoglazed and overglazed porcelain and its effect on plaque accumulation

Satheesh B. Haralur 대한치과보철학회 2012 The Journal of Advanced Prosthodontics Vol.4 No.4

PURPOSE. The aim of this study was to evaluate the efficiency of manual polishing over autoglazed and overglazed porcelain and their effect on plaque accumulation. MATERIALS AND METHODS. Thirty-six porcelain discs were fabricated out of which 18 each was subjected for autoglazing and overglazing. Half surface of the discs was left intact; the remaining half was roughened with medium grit diamond bur. Roughened surfaces were repolished by porcelain polishing kits (Shofu, DFS, Eve). All the surfaces were evaluated by the perthometer and SEM. Six discs from each sample were placed in human volunteer's mouth for 72 hours to evaluate the plaque accumulation. Acquired data was subjected to ANOVA comparative evaluation. RESULTS. Roughened surfaces had average roughness value of 2.88±0.1935 ㎛.The repolished surfaces by porcelain correction kits Shofu, DFS and Eve, average roughness value reduced to 0.6250± 0.1036, 0.9192± 0.0953, 0.9017 ± 0.1305 respectively. Autoglazed and overglazed surfaces showed the mean roughness value (Ra) of 0.4217± 0.0685, 0.3450± 0.0729. SEM study showed the improved surfaces when subjected for polishing. Plaque accumulation percentage was the highest on roughened surface (93.83± 6.2552%), followed by porcelain discs polished by commercial kits. Autoglazed surfaces found to be the best surfaces with the least plaque accumulation (0.5237± 0.4209%). CONCLUSION. All the polishing kits used in the study reduced the average roughness by approximately 77%. Corrected porcelain surfaces should ideally be reglazed, alternatively, polish the surfaces before final cementation.

Effect of alginate chemical disinfection on bacterial count over gypsum cast

Satheesh B. Haralur,Omir S. Al-Dowah,Naif S. Gana,Abdullah Al-Hytham 대한치과보철학회 2012 The Journal of Advanced Prosthodontics Vol.4 No.2

PURPOSE To evaluate the efficacy of sodium hypochlorite (1 : 10) and iodophor disinfectants on alginate impressions along with their effect on the survived bacterium count on the gypsum cast. MATERIALS AND METHODS Four alginate impression on each dentate patients were made, of which Group I were not washed or disinfected, Group II impressions were merely washed with water, Group III were disinfected by spraying with sodium hypochlorite (1 : 10), Group IV were disinfected with iodophor (1 : 213). Gypsum cast (type III) were made from all the impression. Impressions and gypsum cast were swabbed in mid palatal region for bacterial culture. Bacterial colony counting done after 3 days of incubation at 37℃ in blood agar media. The data obtained was analyzed by one way ANOVA test at a significant difference level of 0.05. RESULTS Group I and Group II showed significantly more bacteria compared to Group III and Group IV. Bacterial colonies on the alginate impression and gypsum cast in group disinfected with Sodium hypochlorite (1 : 10) were 0.18, 0.82 respectively compared to group treated with iodophor (1 : 213). There was an increase in bacterial count on dental cast compared to source alginate impressions. CONCLUSION Sodium hypochlorite (1 : 10) was found to be better disinfectant for alginate impression. There was an indication of increase in number of bacteria from alginate impression to making of dental cast. Additional gypsum cast disinfectant procedures need to be encouraged to completely eliminate cross infection to dental laboratory.

Injera (An Ethnic, Traditional Staple Food of Ethiopia): A review on Traditional Practice to Scientific Developments

Satheesh Neela 한국식품연구원 2020 Journal of Ethnic Foods Vol.7 No.-

Injera is fermented Ethiopian ethnic traditional staple food prepared usually form teff flour [Eragrostis tef (Zucc.) Trotter]. Almost all the Ethiopians consume this food at least once in a day. Injera preparation composed of many steps, starting from grain preparation to baking; these all steps are still performing with indigenous knowledge with traditional practices. This Ethiopian national super food appreciating in many western countries due to the superior nutritional properties, especially lack of gluten and good mineral compositions (Rich of Iron). Research on injera preparation from composite flours for nutritional enhancement and sensory quality improvements were took lion share in reported scientific research. However, limited research was reported on preservation of injera by chemical ingredients and natural species, microbes involved in fermentation and spoilage. In addition, very fewer studies were reported on effect of milling quality of injera seed and role of fermentation on anti-nutritional factors degradation. However, scientific review to show the injera traditional practice and scientific research undertaken in this area is hardly found. In considering above all, this review is under taken with objective to review the traditional ethnic practice and scientific research reported on injera preparation.

Isolation and Culture Medium Optimization for Thermostable Extracellular α-Amylase Production by Thermophilic Alicyclobacillus acidocaldarius

G. Satheesh Kumar(사티시 쿠마르),M. Subhosh Chandra(수보쉬 찬드라),K. V. Mallaiah(브이 말라이아),P. Sreenivasulu(스리니바슐루),Yong Lark Choi(최용락) 한국생명과학회 2012 생명과학회지 Vol.22 No.4

고온성 α-아밀라제를 생산하는 내열성 Alicyclobacillus acidocaldarius 균을 인도 Tirupati, Andhra Pradesh 지역의 가열한 미강 열수 추출물에서 분리하였다. 분리균인 내열성 Alicyclobacillus acidocaldarius가 생산하는 세포 외 α-아밀라제의 생산과 성장에 미치는 배양조건을 실험실 규모로 조사하였다. 그 결과 α-amylase의 고생산 최적 조건은 온도 60oC, pH 6.0 및 배지의 전분농도 1.0%, yeast extract와 tryptone은 0.2%를 나타냈다. Surfactantslike Tween-20과 SDS 같은 계면활성제는 0.02%까지 균주의 성장과 효소 생산을 증가 시켰으나, 그 이상의 농도에서는 α-amylase 효소의 생산이 현저하게 감소하였다. A thermophilic Alicyclobacillus acidocaldarius, which produces thermostable α-amylase, was isolated from the hot water effluent of a boiled rice mill near Tirupati, Andhra Pradesh, India. The effect of different culture conditions on the growth and production of extracellular α-amylase by thermophilic A. acidocaldarius was investigated in laboratory scale. The results showed that the optimum conditions for the production of α-amylase are a temperature of 60°C, pH of 6.0, and medium starch concentration of 1.0%, and yeast extract and tryptone of 0.2%. Surfactants, like Tween-20 and SDS, up to 0.02%, were found to increase the bacterial growth and enzymes. Further increase in their concentration resulted in significantly decreased enzyme production.

Some Properties of Bivariate Generalized HypergeometricProbability Distributions

C. Satheesh Kumar 한국통계학회 2007 Journal of the Korean Statistical Society Vol.36 No.3

In this paper we study some important properties of the bivariate gener-alized hypergeometric probability (BGHP) distribution by establishing theexistence of all the moments of the distribution and by deriving recurrencerelations for raw moments. It is shown that certain mixtures of BGHP distri-butions are again BGHP distributions and a limiting case of the distributionis considered.

Recent advancement of NGS technologies to detect active transposable elements in plants

Viswanathan Satheesh,Wenwen Fan,Jie Chu,Jungnam Cho 한국유전학회 2021 Genes & Genomics Vol.43 No.3

Background Unlike peoples’ belief that transposable elements (TEs) are “junk DNAs” or “genomic parasites”, TEs are essential genomic elements that bring about genetic diversity and enable evolution of a species. In fact, transposons are major constituent of chromosome in crop genomes, particularly in major cereal crops, the primary type of which is long terminal repeat (LTR) retrotransposon. Since TE mobilization can be controlled by specifc environmental stimulation and as the result can generate novel genetic variations, it has been suggested that controlled mobilization of TEs can be a plausible method for crop breeding. To achieve this goal, series of sequencing techniques have been recently established to identify TEs that are active in mobility. These methods target and detect extrachromosomal DNAs (ecDNAs), which are fnal products of integration. The newly identifed TEs by these methods exhibit strong transpositional activity which can generate novel genetic diversity and provide useful breeding resources. Conclusions In this mini review, we summarize and introduce ALE-seq, mobilome-seq, and VLP DNA-seq techniques employed to detect active TEs in plants.

Enhanced Production and Partial Purification of Glucoamylase from Mutated Bacillus sp. FME

Gudi Satheesh Kumar,Muni Ramanna Gari Subhosh Chandra,Yakasiri Nagasai Sujana,Bontha Rajasekhar Reddy,Yong Lark Choi 한국응용생명화학회 2009 Applied Biological Chemistry (Appl Biol Chem) Vol.52 No.5

In this study, a potent newly-isolated glucoamylase producing actively growing cells of Bacillus sp.FME was subjected to UV irradiation and ethidium bromide (EtBr) mutagenesis. The promising colonies were further screened for glucoamylase production via plate assays and submerged enzyme production at the flask level. Amongst all of the tested colonies, the best mutant, Bacillus sp. FME 2, selected from UV irradiation (20 min) and EtBr (1 mg/mL), was shown to be the most promising. The yield of glucoamylase generated by the mutant strain was approximately 3.0 fold and 1397 U/mL with an incubation period of 24 h, which was larger than the yield generated by the wild-type strain. The glucoamylase was partially purified using ammonium sulphate precipitation followed by gel exclusion chromatography. The enzyme was partially purified 3.0-fold to homogeneity with a final recovery of 66% and a specific activity of 1145 U/mg protein for the mutant strain. The molecular mass was approximately 67.1 kDa, as determined by SDS-PAGE. The active band was observed as a clear colorless area on zymogram analysis, which indicated an absence of glucoamylase isoforms. The results of thin-layer chromatography identified this enzyme as a glucoamylase.

Glucoamylase from a Newly Isolated Aspergillus niger FME: Detergent-Mediated Production, Purification, and Characterization

Gudi, Satheesh Kumar,Gurramkonda, Chandrasekhar,Rather, Gulam,Chandra, Muniramanna Gari Subohsh,Mangamuri, Usha Kiranmayi,Podha, Shdhakar,Choi, Yong-Lark 한국응용생명화학회 2013 Applied Biological Chemistry (Appl Biol Chem) Vol.56 No.4

Glucoamylase (EC 3.2.1.3) is an important group of enzymes in starch processing, also referred to as amyloglucosidases, which are exo-acting amylases that release glucose from the non-reducing end of starch and related oligosaccharides. The glucoamylase newly isolated from the Aspergillus niger FME) was reported for the first time. This enzyme was produced by detergent-mediated release and purified to ~9.11 fold using Sephadex-G 100 and ion-exchange chromatography. Molecular mass of the glucoamylase was ~36 kDa as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The product of starch hydrolysis, analysed by thin-layer chromatography, showed the presence of glucose. The optimum pH and temperature for glucoamylase activity was 5.0 and $45^{\circ}C$, respectively. The $K_m$ and $V_{max}$ values of the enzyme were also determined using soluble starch as substrate as $94{\mu}g/mL$ and 39.02 U/mg, respectively. Moreover, glucoamylase was slightly activated by presence of Na and K ions and 10-20% inhibition was observed in presence of $Zn^{2+}$, $Sn^{2+}$, $Mg^{2+}$, $Ni^{2+}$, $Mn^{2+}$, and almost 80% with $Cu^{2+}$ ions, whereas the presence of ethylene diamine tetra acetic acid (EDTA) did not show significant inhibition. Glucoamylase, also assayed for surfactant property, shows significant surfactant tolerance at high concentrations of detergent and can retain 90% of its activity. Finally, secondary structure analysis of glucoamylase by circular dichroism spectroscopy showed the presence of 48% ${\alpha}$-helix, 11% ${\beta}$-sheet, and 41% random structure.

Temporal Variations in the Antifouling Activity of Extract of the Soft Coral Sarcophyton trocheliophorum Collected from the Red Sea

Sathianeson Satheesh,Mohammad Abulaziz Ba-Akdah 한국해양과학기술원 2022 Ocean science journal Vol.57 No.2

Soft corals are considered as a prospective resource for the isolation of natural product antifoulants. In this study, the temporal variations in the antifouling activity of the crude extract of the soft coral Sarcophyton trocheliophorum samples collected from the Jeddah coast of Saudi Arabia during summer (June–August 2018) and winter seasons (December 2018–February 2019) were assessed using laboratory tests. The crude extract was tested against biofilm-forming bacteria and barnacle larvae in the laboratory. The results indicated significant variations (P < 0.001) in the antifouling activity of the extracts between the samples collected during the summer and winter seasons. The extract of the soft coral samples collected during the summer season showed higher inhibitory activity against the fouling bacteria and barnacle larva. In addition, the surface-associated bacteria abundance on the soft corals were analysed and the results showed higher abundance on winter season samples. Further, GC–MS analysis indicated differences in the metabolite composition with the abundance of compounds such as cis-z-a-Bisabolene epoxide and caryophyllene oxide being high in summer samples and Isoaromadendrene epoxide and β-cembrenediol showing a higher peak area percentage in winter samples. Overall, this study revealed temporal variations in the antifouling activity and metabolite composition of the Red Sea soft corals.