No abstract

Tumbuhan Andrographis paniculata (Sambiloto) memproduksi beragam metabolit sekunder dengan berbagai aktivitas biologi, termasuk antibakteri. Selain dari tumbuhan alami, potensi senyawa antibakteri dari tumbuhan A. paniculata dapat dieksplorasi dari jamur endofitiknya. Tujuan dari penelitian ini adalah melakukan kajian terkait potensi jamur endofitik yang berkolonisasi dalam jaringan bunga tumbuhan A. paniculata. Secara garis besar penelitian ini terdiri dari isolasi, kultivasi, ekstraksi, uji antibakteri dan uji kandungan metabolit sekunder dari jamur endofitik pada bunga tumbuhan A. paniculata. Hasil uji aktivitas antibakteri terhadap ekstrak EtOAc jamur BS-1 yang diisolasi dari bunga tumbuhan A. paniculata menunjukkan kemampuannya dalam menginhibisi pertumbuhan semua bakteri uji pada konsentrasi 1%, 3%, dan 5%. Studi terkait senyawa yang berkontribusi dalam sifat antibakteri ini perlu dilakukan lebih lanjut. Untuk infomasi bagi kita semua bahwa penelitian terkait kajian sifat antibakteri dari jamur yang hidup pada bunga A. paniculata baru pertama kali dilakukan pada kesempatan ini.

This descriptive research was done on atomic structure and periodic table topics in SMAN 7 Padang. On these topics, students had difficulties on achieving learning goals where only 38% students could achieve the minimum defined criteria. This research aims to determine percentage of learning difficulties in all learning indicators and find factors that cause learning difficulties. 57 tenth grade students as research sample were obtained through cluster sampling technique. Research instruments used were diagnostic test and questionnaire and data were then analyzed descriptively. Analysis showed that learning difficulties were 91.2%, 13.2%, 88.3%, 51.5%, 70%, 64%, 84%, 84%, and 74.9% in the indicator of describing subatomic particles and their discovery; determining atomic number and mass number of elements and isotopes; describing atomic model according to Dalton, Thomson, Rutherford, Bohr, and wave mechanics; explaining electron configuration and orbital diagrams; determining quantum number and orbital shape; describing development of periodic system; modern periodic system; periods and groups in periodic table; and periodic trends of elements respectively. Students’ learning difficulties were influenced by school factors including teaching methods 35.8%, curriculum 47.5%, teacher relation with students 49.1 %, relation among students 41.7%, time and school discipline 33.3%, teaching tools 39.4% and school building condition 17.7%.

This research is to create a practical guide alternative based environment forsenior high school students and determine the validity, practicality, and effectivity level of the practical guide itself. The type of this research is Research and Development (R & D). The development model used in this research is the Plomp model which consists of three phases: preliminary research, prototyping phase, and assessment phase. The research instrumentis questionnaire of validity, practicality, and effectivity sheet. Practical guide alternative-based environment validated by 4 validators and tested to 17 students of class XII IPA 3 SMAN 1 Rambatan and 29 students of class XI IPA 4 SMA N 1 Kec. Guguak of the academic year 2017/2018. The moment kappa of validity was 0.79. The practicality level of the teacher's response questionnaire was 0.84. Based on the questionnaire of student response, the value of moment kappa is 0,77 in SMAN 1 Rambatanand and 0,90 in SMAN 1 Kec.Guguak with high category practicality for small group test and moment kappa value is 0,81 in SMAN 1 Rambatan and 0,84 in SMAN 1 Kec. guguak with the highest category practicality on the field test. The effectivity level of the teacher's response questionnaire was 0,89. Based on the questionnaire of student response, the value of momen kappa is 0,76. The results of the research can be concluded that the practical guide alternative based environmentfor senior high school students has a high validity category, highest practicality category, high effectivity category from students, and highest effectivity from teachers.

The amine material is part of the functional group of carbon compounds studied in the even semester in the class of 3rd grade High School. This material is closely related to everyday life, especially the structures, nomenclature, physical properties, chemical properties, synthesis, uses and spectra inframerah (IR). Natural and synthetic amines play a role in human physiological and biological activities, including hormones, amino acids, nicotine, anti-irritant shampoos, engine lubricants, and drugs classified as Narcotics, Psychotropics and Additives (Napza). Students can be given a problem in the learning process related to reality. One of the learning models that can be used in discussing amine material is the Problem Based Learning (PBL) learning model because amines are close to life. This research aim is to develop LKPD and determine the validity test. The type of research is R&D (Research and Development) with a 4-D model, namely define, design, develop and disseminate, which is limited to create on validity tests using research instruments in the form of questionnaires. The research was conducted by testing the validity of the resulting LKPD. The research data by five expert validators were analyzed through the Aiken's V formula scale. Based on the analysis of the actual validity of test questionnaires, Problem Based Learning-based worksheets have been produced, especially on the excellent amine material (0.87).