Quality Improvement of White Pepper with Processing through Optimizing the Ratio of Starter Culture from Acetobacter sp., Bacillus subtilis, and Bacillus cereus

Fermentation process using known microbial species can be exploited for the processing of white pepper. It is expected to generate quality of white pepper in a short period soaking time. This research aimed to study characteristics of white pepper through a fermentation process by addition of combination isolates of Acetobacter sp., B. subtilis, and B. cereus. After threshing, 2 kg of fresh pepper berries was soaked in water mixed with starter culture. The experiment used a completely randomized design, two replications. The treatment consisted of: A) starter culture ratio of Acetobacter sp.: B. subtillis: B. cereus (A1 = 0:0:0; A2 = 1:1:1; A3 = 2:1:1; A4 = 1:2:1; and A5 = 1:1:2) and soaking time (B1 = 5 and B2 = 7 days). Fermented pepper was decorticated, washed, and dried. The best treatment was fermented for 7 days with the combination isolates of Acetobacter sp., B. subtilis, and B. cereus with ratio 2:1:1. This condition produced white pepper in fulfilling in requirement of SNI standards with piperine and essential oil contents and TPC of 5.95%, 2.95% and 1.1 x 102 CFU/g, respectively. This process is expected to generate high quality of white pepper in a short soaking time

ANTIMICROBIAL PROPERTIES OF NANO-EMULSION FORMULATED FROM GARLIC, GINGER AND CINNAMON EXTRACTS AGAINST Escherichia coli AND Salmonella typhi

Garlic, ginger and cinnamon had been reported for their antimicrobial activities, for instance against Escherichia coli and Salmonella typhi. The present study aimed to test antimicrobial activities of nanoemulsion of the mixture of garlic, ginger and cinnamon. The nanoemulsion was formulated from the mixture of garlic and ginger extracts and cinnamon essential oil at the ratio of 80:10:10 using a high pressure homogenizer at 300 bars for 5 cycles. The  nanoemulsion powder was prepared using a spray dryer with the inlet and outlet temperatures of 160–170 °C and 70–80 °C, respectively, and maltodextrin as a filler. The nanoemulsion was tested against E. coli and S. typhi. The particle size of nanoemulsion and powdered formulas were characterized using a scanning electron microscope. The LC50 values were identified based on the Brine Shrimp Lethality Test. The results showed that quality of the raw materials confirmed the WHO requirements. The particle size of the emulsion ranged from 151 to 306 nm with the polydispersity index of 0.39–0.52. The 10% and 15% active compounds of the nanoemulsion inhibited E. coli and S. thypi with the LC50 values of 680.15–970.50 ppm and 607.17–903.31 ppm, respectively. The study suggests that the nanoemulsion of a mixture of garlic, ginger and cinnamon extracts could be developed as a food preservative

Pengembangan Asesmen Formatif Berbasis Problem Based Learning untuk Meningkatkan Keterampilan Berpikir Kritis: Need Assessment Study

Curriculum, learning, and assessment are the main keys to educational success. Formative assessment is an interactive strategy to identify what must be learned and how teaching is formulated according to educational needs. The questionnaire results show that chemistry teachers in schools still do not utilize formative assessments to measure the progress of the educational process. This research aims to collect information regarding the need for developing formative assessments for problem-based learning to improve students' critical thinking skills in the sub-material of vapor pressure reduction. A qualitative method was used in this research, involving 40 chemistry teacher participants in the province of North Sumatra, Indonesia. Participants were asked questions regarding their views on the need for assessment development through a questionnaire. Several of them were interviewed semi-structured to gain more in-depth information from the questionnaire answers. Data were analyzed using the Miles and Huberman model which consists of the steps: collection, reduction, display, and conclusion. The research results show that teachers agree that PBL-based formative assessments are needed to measure students' critical thinking skills. They suggest researchers choose Ennis's version of critical thinking indicators because they have good detail and warn researchers to practice Problem-Based Learning syntax correctly. Apart from that, it is hoped that successful learning in the classroom can be achieved through the use of products from the development of this formative assessment, namely test instruments and observation sheets

The compatibility analysis of subject matter description with basic competence at science textbook for 7th grade of junior high school

The aim of this research is to analyze the quality of science textbooks for 7th grade of Junior High School in Bandung City. This research use content analysis method and data analysis with quantitative descriptive analysis technique. The compatibility analysis of subject matter description with basic competence use instrument which adopted from the instrument of BSNP and based on three indicators, (1) completeness, (2) broadness, and (3) deepness. Completeness based on the presentation of subject matter, broadness based on the presentation of concept, definition, procedure, or example which support to the subject matter, and deepness based on subject matter explanation. The samples are one electronic textbook (BSE), be code in A and two non-electronic textbooks (non-BSE), be code in B and C. The samples selected by purposive sampling technique. Analysis result shows that the completeness of book A, B, and C are 100%, 96,15%, and 96,15% consecutively. The broadness of book A, B, and C are 100%, 88,46%, and 84,62% consecutively. The deepness of book A, B, and C are 92,31%, 88,46%, and 73,08% consecutively. So, book A (BSE) have better quality than book B and C (non-BSE)

Pre-Service Chemistry Teacher’s Conception About Chemistry of The Rare Earth Elements

Rare Earth Elements (REE) is an interesting chemistry topic, especially due to current technology development. However, new learning designs of REE need to be developed for Pre-service Chemistry Teachers (PCT) as it is not yet available. A good design is constructed by analyzing PCT pre-conceptions based on the technical difficulties faced by the students during teaching process. The study aims to identify PCT's pre-conceptions focusing on REE topic. We conducted this research involving 17 chemistry education students at the Universitas Pendidikan Indonesia, Bandung. Data was collected through interviews and analyzed using the Qualitative Content Analysis (QCA) method. Our results highlight that PCT had difficulties with chemistry content of REE, especially about electronic configuration, magnetic, and luminescence properties. In addition, PCT faced difficulties correlating electronic configuration's chemistry content into contexts. Based on the interview results, 88.2% of the students agree with the development learning design for undergraduate chemistry students. As a result, we conclude that technical difficulties and misconceptions about REE can be overcome by developing the learning design based on the need of the students.

Profil Literasi Sains Peserta Didik SMK pada Penerapan Pembelajaran Projek Electroplating Berbasis Green Chemistry

Scientific literacy is one of the main keys for education personnel in facing the challenges of the 21st century which continues to experience global changes. Project learning is carried out to increase scientific literacy and achieve sustainable development. This study aims to describe the scientific literacy profile of vocational students in the application of green chemistry-based electroplating learning projects. The principles of green chemistry raised in the electroplating project are the use of safe chemicals, the use of green solvents, and waste prevention. The research method used was a descriptive analysis. The research subjects were 27 students from the Industrial Mechanics Engineering program in the Department of Technology and Engineering at a Vocational School in the city of Cimahi for the 2022-2023 Academic Year, selected using the convenience sampling technique. Data collection techniques were carried out using 20 scientific literacy test instrument questions with four answer choices that have been validated and tested for reliability. Data analysis was carried out by paired t-test on pretest and posttest values using the Microsoft Excel program. The scientific literacy profile of SMK students in the domain of science knowledge is categorized as low with a percentage of 48%, the scientific competence domain is categorized as moderate with a presentation of 66%, and the attitude domain is categorized as moderate with a percentage of 63%

Examining the Correlation between Critical Thinking and Problem-Solving Skills of Junior High School Students Against Climate Change

This research examined the association between critical thinking and problem-solving skills among junior high school students, specifically focusing on Climate Change. The participants in this study included 272 students from XYZ Junior High School Rangkasbitung, comprising grades 8 and 9, during the even semester of the 2022/2023 academic year. A previously validated multiple-choice instrument with four answer choices assessed their abilities. The collected data were analyzed using SPSS 23 to determine the correlation and Winstep 5.4.1 for categorizing students' abilities. The findings revealed that the students obtained an average score of 42.82 for critical thinking and 43.53 for problem-solving skills. The correlation coefficient was calculated to be 0.74, indicating a strong and positive relationship between critical thinking and problem-solving skills. It was observed that an increase in the critical thinking score accompanied an increase in the problem-solving score. Additionally, the determination value of 0.546 indicated that critical thinking skills could explain 54.6% of the variance in problem-solving skills, while other factors influenced the remaining 45.4%.Penelitian ini mengkaji hubungan antara berpikir kritis dan kemampuan memecahkan masalah pada siswa sekolah menengah pertama, khususnya yang berfokus pada Perubahan Iklim. Partisipan dalam penelitian ini adalah 272 siswa SMP XYZ Rangkasbitung yang terdiri dari kelas 8 dan 9 selama semester genap tahun ajaran 2022/2023. Instrumen yang digunakan berupa pilihan ganda yang telah divalidasi sebelumnya dengan empat pilihan jawaban. Data yang terkumpul dianalisis menggunakan SPSS 23 untuk menentukan korelasi dan Winstep 5.4.1 untuk mengkategorikan kemampuan siswa. Hasil temuan menunjukkan bahwa siswa memperoleh skor rata-rata 42,82 untuk berpikir kritis dan 43,53 untuk keterampilan pemecahan masalah. Koefisien korelasi dihitung menjadi 0,74, menunjukkan hubungan yang kuat dan positif antara berpikir kritis dan kemampuan memecahkan masalah. Terlihat bahwa peningkatan skor berpikir kritis dibarengi dengan peningkatan skor pemecahan masalah. Selain itu, nilai determinasi sebesar 0,546 menunjukkan bahwa keterampilan berpikir kritis dapat menjelaskan 54,6% varian keterampilan pemecahan masalah, sedangkan sisanya sebesar 45,4% dipengaruhi oleh faktor lain

SCIENCE, ENGINEERING, AND TECHNOLOGY OF DYE SENSITIZED SOLAR CELLS: A DIDACTICAL DESIGN BASED ON TECHNOCHEMISTRY EDUCATION

This research was conducted to build a view of the nature of science and technology (VNoST) chemistry education students' ability through the didactical design reconstruction. The material taken is Dye-Sensitized Solar Cells (DSSCs) topic with technochemistry education model. It is a model that looked at education from the perspective of engineers and scientists who work not only on inquiry but also on a design perspective. Based on literature research, Indonesian students had low academic literacy performance as revealed in PISA (Program for International Student Assessment) study from 2000-2015. This problem can be caused by a weak teacher's abilities of the nature of science and technology (VNoST). This research's method is Research and Development (R&D) through the Model of Educational Reconstruction (MER). The instruments used were the VNoST questionnaire, interview guidelines, and content analysis guidelines. This study's subjects were 25 prospective chemistry education students in the 6th semester for pre-conception study and ten students for implementation study at one of State Universities in Indonesia. The didactical design of learning that has been developed had several advantages, including the prediction of student responses and the anticipation of educators as well as the essential material that is a barrier to student learning. Analysis of the VNoST understanding construction patterns is explored further so that the reasons that underlie students in defining science and technology and their relationship are obtained. The implementation study proved that understanding VNoST students after attending didactical design learning improved by changing students' views on science and technology to be more accurate

Chemistry Learning via Distance Learning during the Covid-19 Pandemic

This research is a descriptive study that describes the learning of chemistry during the Covid-19 pandemic. The respondents in this study were 127 high school students from the West Java and Banten provinces. A Google Form questionnaire was used to collect the data. The results showed that the most widely used online class applications were WhatsApp Group feature, Google Classroom, and Zoom. Students also used printed textbooks, e-books, and student worksheets as learning media. Students did laboratory practice at home using easily found tools and materials. However, a small portion of the respondents ( 11 %) used materials purchased from a chemical store, and another small portion of the respondents ( 14 %) used virtual laboratories. They reported the results of their practice by making a laboratory practice report as well as through video activities and Microsoft PowerPoint for presentation. Students learn from home with varying durations. Most students experienced obstacles during the learning process so that they prefer learning face-to-face in class as usual. Therefore, the teacher must prepare a variety of strategies for distance learning so that the students can learn chemistry from home with fun. Some strategies that can be applied are providing audio-visual learning media or computer/android-based games for chemistry, using the online class application that accommodates interactions similar to face-to-face learning, providing laboratory practice using tools and materials that can be easily found around the house, providing virtual lab application, and providing more opportunities for students to ask questions about chemistry topics that they do not understand