A novel antioxidant peptide, purified from <i>Bacillus amyloliquefaciens</i>, showed strong antioxidant potential via Nrf-2 mediated heme oxygenase-1 expression

Rahman, Md. Saifur,Hee Choi, Yun,Seok Choi, Yoon,Alam, Md. Badrul,Han Lee, Sang,Cheol Yoo, Jin Elsevier 2018 Food chemistry Vol.239 No.-

<P><B>Abstract</B></P> <P>A novel antioxidant peptide YD1 (∼1.0kDa), purified from the strain <I>Bacillus amyloliquefaciens CBSYD1</I>, displayed activity in several <I>in vitro</I> assays and was also efficient against Gram-positive, Gram-negative as well as multidrug-resistant (MDR) bacteria. Strain growth was adapted to bile-salt conditions where a clear halos-zone was observed in a bile-salt plate assay and was viable in different digestive track conditions. YD1 treatment on RAW 264.7 cells increased the transcriptional and translational activities of NF-E2-related factor-2 (Nrf-2) through the enhanced levels of heme oxygenase-1 (HO-1). Furthermore, the YD1-treated group showed higher levels of antioxidant enzymes compared to the oxidative stress group. YD1 demonstrated a strong antioxidant activity by decreasing nitric oxide (NO) and reactive oxygen species (ROS) in RAW 264.7 cells. This study suggests that YD1 and the strain could be a natural antioxidant and a probiotic candidate respectively.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A novel glycine-rich antioxidant peptide purified from <I>Bacillus amyloliquefaciens.</I> </LI> <LI> Showed antioxidant potential via Nrf-2 mediated heme oxygenase-1 expression. </LI> <LI> YD1 displayed active against gram-positive, negative and resistant bacteria. </LI> </UL> </P>

Purification and identification of novel alkaline pectinase PNs31 from Bacillus subtilis CBS31 and its immobilization for bioindustrial applications

Md. Saifur Rahman,김영균,Md Maruf Khan,이상훈,최윤희,조승식,박철환,유진철 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.11

A robust alkaline pectinase PNs31 was produced from Bacillus subtilis CBS31 that was isolated from kimchi (a traditional Korean fermented food). The isolated strain CBS31 was identified as having 99.93% similarity to Bacillus subtilis subsp. The PNs31 was purified to homogeneity using two-step column purification, with an estimated 13.6% pectinase yield and 29.2-fold purity. The molecular mass (~35 kDa) and the N-terminal sequence residues of PNs31 established it as a novel pectinolytic enzyme. PNs31 was stable in the alkaline pH range (9-14) and up to 70 oC and had an optimum pH and temperature were 12.2 and 60 oC, respectively. PNs31 had definite Vmax and Km values of 220.43 mmol/min and 0.42mg/mL, respectively, when different concentrations (5 to 50mg/mL) of pectin were used as substrate. To develop the functional stability and reusability of the pectinase enzyme, PNs31 was immobilized in calcium alginate beads. The result was that the immobilized enzyme maintained approximately 83% and 65% relative activity in the second and third cycles of reusability experiments, respectively.

A Simple and Robustness Algorithm for ECG R- peak Detection

Rahman, Md Saifur,Choi, Chulhyung,Kim, Young-pil,Kim, Sikyung The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.5

There have been numerous studies that extract the R-peak from electrocardiogram (ECG) signals. All of these studies can extract R-peak from ECG. However, these methods are complicated and difficult to implement in a real-time portable ECG device. After filtration choosing a threshold value for R-peak detection is a big challenge. Fixed threshold scheme is sometimes unable to detect low R-peak value and adaptive threshold sometime detect wrong R-peak for more adaptation. In this paper, a simple and robustness algorithm is proposed to detect R-peak with less complexity. This method also solves the problem of threshold value selection. Using the adaptive filter, the baseline drift can be removed from ECG signal. After filtration, an appropriate threshold value is automatically chosen by using the minimum and maximum value of an ECG signals. Then the neighborhood searching scheme is applied under threshold value to detect R-peak from ECG signals. Proposed method improves the detection and accuracy rate of R-peak detection. After R-peak detection, we calculate heart rate to know the heart condition.

Evaluation of Abelmoschus Esculentus Seed for Antioxidant and Phytochemical Analysis Using In vitro Assays

Rahman, Md. Saifur,Yoo, Jin Cheol The Basic Science Institute Chosun University 2014 조선자연과학논문집 Vol.7 No.4

The aim of this study was to assess the in vitro potential of methanolic seed extract of Abelmoschus esculentus as a natural antioxidant. The DPPH activity of the Ethyl acetate soluble fraction (10, 20, 40, 80, and $160{\mu}g/mL$) was increased in a dose dependent manner, which was found in the range of 18.97-90.47% as compared to ascorbic acid 26.44-93.71%. The $IC_{50}$ values of Ethyl acetate soluble fraction (EAES) and ascorbicacid in DPPH radical scavenging assay were obtained to be 28.12 and $18.43{\mu}g/mL$, respectively. Measurement of polyphenol content of the EAES of A. esculentus seed was achieved using Folin-Ciocalteau reagent containing 53.80 mg/g of total phenolic content, which was found signicantly higher when compared to reference standard gallic acid. Similarly total flavonoids and proabthocyanidis of EAES and chloroform soluble fraction (CAES) were found significantly 147 mg/g and 14.24 mg/g respectively when both compared to reference standard quercetin. EAES exhibited high significant lipid peroxidation inhibition effects in a dose-dependent manner, with $IC_{50}$ values of $38.08{\mu}g/mL$, whereas, standard quercetin, with $IC_{50}$ value of $36.67{\mu}g/mL$. All extract/fractions showed dose dependent reducing power ability and these differences were statistically significant (p<0.001). The results obtained in this study clearly indicate that A. esculentus seed has a signicant potential to use as a natural antioxidant agent.

Evaluation of Abelmoschus Esculentus Seed for Antioxidant and Phytochemical Analysis Using In vitro Assays

Md. Saifur Rahman,Jin Cheol Yoo 조선대학교 기초과학연구원 2014 조선자연과학논문집 Vol.7 No.4

Identification and Characterization of a Novel Pectinolytic Enzyme CBS 31 Produced by Bacillus subtilis Isolated from Fermented Vegetable

Md. Saifur RAHMAN,Jin Cheol YOO 한국생물공학회 2016 한국생물공학회 학술대회 Vol.2016 No.10

A Simple and Robustness Algorithm for ECG R- peak Detection

Md Saifur Rahman,ChulhyungChoi,Young-pil Kim,Sikyung Kim 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.5

There have been numerous studies that extract the R-peak from electrocardiogram (ECG) signals. All of these studies can extract R-peak from ECG. However, these methods are complicated and difficult to implement in a real-time portable ECG device. After filtration choosing a threshold value for R-peak detection is a big challenge. Fixed threshold scheme is sometimes unable to detect low R-peak value and adaptive threshold sometime detect wrong R-peak for more adaptation. In this paper, a simple and robustness algorithm is proposed to detect R-peak with less complexity. This method also solves the problem of threshold value selection. Using the adaptive filter, the baseline drift can be removed from ECG signal. After filtration, an appropriate threshold value is automatically chosen by using the minimum and maximum value of an ECG signals. Then the neighborhood searching scheme is applied under threshold value to detect R-peak from ECG signals. Proposed method improves the detection and accuracy rate of R-peak detection. After R-peak detection, we calculate heart rate to know the heart condition.

적응형 필터와 가변 임계값을 적용하여 잡음에 강인한 심전도 R-피크 검출

세이푸르(MD Saifur Rahman),최철형(Chul-Hyung Choi),김시경(Si-Kyung Kim),박인덕(In-Deok Park),김영필(Young-Pil Kim) 한국산학기술학회 2017 한국산학기술학회논문지 Vol.18 No.12

심전도(ECG) 신호에서 R-피크를 추출하는 기법에 대하여 많은 연구가 진행 되어 왔으며, 다양한 방법으로 구현되어 왔다. 그러나 이러한 검출 방법 대부분은 실시간 휴대용 심전도 장치에서 구현하기가 복잡하고 어려운 단점이 있다. R-피크 검출을 위해서는 심전도 데이터에 대하여 베이스라인 드리프트 및 상용전원 잡음 제거 등의 적절한 전처리 및 후가공이 필요하며, 특히 적응형 필터를 활용한 기법에서는 적절한 임계값을 선택하는 것이 중요하다. 적응형 필터의 임계값을 추출하는 방식에서는 고정형(Fixed) 및 적응형(adaptive)으로 구분할 수 있다. 고정 임계 값 추출 방식은 고정된 임계값 보다 낮은 값의 입력이 들어오는 경우에 R-피크 값을 감지하지 못하는 경우가 있으며, 적응 임계값 추출 방식은 때때로 잡음에 의한 잘못된 임계값을 도출하여, 다른 파형(P혹은 T파)의 피크를 감지하는 경우도 나타난다. 본 논문에서는 계산상의 복잡성이 적고, 코드구현이 단순하면서도 잡음에 강인한 R-피크 검출 알고리즘을 제안한다. 제안된 방식은 앞서 설명한 임계값 추출 문제를 해결하기 위해서, 적응형 필터를 사용해, 심전도 신호에서 베이스 라인 드리프트 제거를 하여 적절한 임계값을 계산하도록 한다. 그리고 필터 처리된 심전도 신호의 최소 값과 최대 값을 사용하여 적절한 임계값이 자동으로 추출 되도록 한다. 그런 다음 심전도 신호로부터 R-피크를 검출하기 위해 임계값 아래에서 ‘neighborhood searching’ 기법이 적용된다. 제안된 방법은 R-피크 검출의 정확도를 향상시키고, 계산 량을 줄여 검출 속도가 보다 빨라지도록 하였다. 다음으로 R-피크 값이 검출 되면, R-R interval 등의 값을 이용해 심박 수를 계산할 수 있도록 한다. 실험결과 심박 수 검출 정확도와 감도가 약 100%로 매우 높았음을 확인할 수 있었다. There have been numerous studies on extracting the R-peak from electrocardiogram (ECG) signals. However, most of the detection methods are complicated to implement in a real-time portable electrocardiograph device and have the disadvantage of requiring a large amount of calculations. R-peak detection requires pre-processing and post-processing related to baseline drift and the removal of noise from the commercial power supply for ECG data. An adaptive filter technique is widely used for R-peak detection, but the R-peak value cannot be detected when the input is lower than a threshold value. Moreover, there is a problem in detecting the P-peak and T-peak values due to the derivation of an erroneous threshold value as a result of noise. We propose a robust R-peak detection algorithm with low complexity and simple computation to solve these problems. The proposed scheme removes the baseline drift in ECG signals using an adaptive filter to solve the problems involved in threshold extraction. We also propose a technique to extract the appropriate threshold value automatically using the minimum and maximum values of the filtered ECG signal. To detect the R-peak from the ECG signal, we propose a threshold neighborhood search technique. Through experiments, we confirmed the improvement of the R-peak detection accuracy of the proposed method and achieved a detection speed that is suitable for a mobile system by reducing the amount of calculation. The experimental results show that the heart rate detection accuracy and sensitivity were very high (about 100%).

Section of Pectinolytic Enzyme Producing Strains Isolated from Korean Fermented Food and Characterization Potential Pectinases

Md. Maruf KHAN,Md. Saifur RAHMAN,Youngkyun KIM,Yoon Seok CHOI,Sudip REGMI,Jin Cheol YOO 한국생물공학회 2016 한국생물공학회 학술대회 Vol.2016 No.10

A 2D-DCT Image Processing in Matlab and Voice Informatics Based Remote Home Monitoring and Security System

Md. Biplob Hossain,M. Saifur Rahman 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.2

This paper proposes, designs and constructs an image recognition & voice technology based security system by highlighting the advantages of image processing technology and voice synthesis technology which are presence in the electronic market. This paper mainly approaches towards enhanced security by checking the tag image of the operator as well as recognizing voice which are validated previously by this system just using simply a web-camera or closed circuit television (CCTV) camera and a voice recording software system and gives the signal in terms of alarm, Alert Light, message via global system for mobile communication (GSM)/ general packet radio service (GPRS) to the consumer mobile number/the nearest police station’s mobile number.