The aim of the research were isolation, purification and characterization of Bacillus subtilis phytase from Holiwood Gresik. The research was done in two stages; the first include enzyme isolation, precipitation with amonium sulphate, dialysis, gel filtration chromatography, SDS-PAGE analysis, while second determining optimum pH, optimum temperature, the effect of pH and temperature to enzim stability, the values of KM and Vmax Bacillus subtilis phytase from Holiwood Gresik. The first stage research design were One Shot Case Study and Post Test Only Control Group Design, while the second stage were Post Test Only Control Group Design and Factorial Design. The data being analyzed by one-way and two-way Anova. The results of research showed that Bacillus subtilis phytase has the molecular mass of 36.5 kDa, optimum pH at 6.5–7.0, optimum temperature at 41° C and it was found to be stable for 30 minute incubation at pH 7 or 30° C with 2% or 3% lost of its activity respectively. KM value was 0.62 mM and VMax 0.393 mmol/ml/minute.

This study aims to analyze prospective science teachers’ information literacy and scientific argumentation skills and their correlations in online learning during the COVID-19 pandemic. This survey research with a cross-sectional design involved 342 students from a state university in Surabaya. The survey was given online to all respondents with a response rate of 77%, consisting of 23 men and 241 women. The information literacy skill instrument was adapted from the eight indicators of the empowering eight model and declared valid. Indicators include the ability to identify, explore, select, organize, create, present, access input, and use information. The argumentation skills instrument consists of four indicators: the ability to identify claims and their qualifications, identify types of data and their quality, identify reasons and quality, and identify objections and counter-arguments. In contrast to the results of previous studies in this study, prospective teachers’ information literacy obtains an average of 83% in a good category. Based on the correct answers to the four indicators, the argumentation skills used obtained an average score of more than 50% on the less and very poor criteria. Based on the SPSS one-tailed correlation test, a correlation coefficient of 0.103 is obtained with very low criteria. This study concludes that students’ information literacy skills are in line with their argumentation skills but in very little correlation.

The implementation of STEM-Inquiry learning puts forward the process of how students independently acquire knowledge through problem solving and have the ability to use that knowledge. STEM-Inquiry learning supported by the use of the CCR platform can support online learning activities, allow students to work in groups, and help students not only memorize concepts, but can understand and apply the acquired knowledge in everyday life. This study aims to determine student responses to the application of STEM-Inquiry learning on the topic of food loss and food waste. This research is a quantitative descriptive study using a survey method. The subjects of this study were students of Science Education Class of 2019 State University of Surabaya. The research instrument used was a questionnaire form. The questionnaire form provided consisted of 20 questions developed from 7 indicators, namely interest, novelty, convenience, clarity, interest, assessment, and response. The results showed that the average percentage of student questionnaire responses was 84.9% which was categorized as very positive, meaning that students had an interest and were interested in being involved in a meaningful learning experience. Based on this, it can be concluded that the application of STEM-Inquiry learning on the topic of food loss and food waste received a very positive response from students