Article Per Year (5 Year)
p-Index From 2021 - 2026
1.037
P-Index
This Author published in this journals
All Journal ILMU KELAUTAN: Indonesian Journal of Marine Sciences Pharmaciana: Jurnal Kefarmasian Bioeksperimen: Jurnal Penelitian Biologi Jurnal Pengabdian Papua SPEKTRA: Jurnal Kajian Pendidikan Sains
Djohan Djohan
Universitas Kristen Satya Wacana
Agriculture, Biological Sciences & Forestry Humanities Earth & Planetary Sciences Education Languange, Linguistic, Communication & Media Medicine & Pharmacology Other

Published : 5 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 5 Documents
Search

 1 
Exploration of Plastic-Degrading Bacteria From Marina Beach, Semarang, Central Java Awalina Choirunnisa Rachmawati; Anggara Mahardika; Djohan Djohan; A.B. Susanto; Bibin Bintang Andriana
ILMU KELAUTAN: Indonesian Journal of Marine Sciences Vol 26, No 4 (2021): Ilmu Kelautan
Publisher : Marine Science Department Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/ik.ijms.26.4.247-253

Abstract

Plastic waste has threatens the environment and affect to the economic and tourism sectors, marine life, coastal ecosystems and human health. World Wide Fund for Nature (WWF) states that 85% of waste in the oceans is plastic. The Ministry of Environment and Forestry also noted that Indonesia experienced an increase in plastic waste from 14% in 2013 to 16% in 2016.  By 2020 the volume of plastic waste in Indonesia predicted to reach 67.8 million tons. Plastic waste takes 100-500 years to completely decompose. An alternative solution is to involve microorganisms to decompose plastic polymers. However, plastic waste reducing bacteria isolated from coastal ecosystem has not been much explored. In this study, an exploration of natural bacteria that degrades plastic waste from coastal ecosystems is carried out. Plastic samples were collected from the Marina Beach Semarang, Central Java. Plastic samples were taken from a depth of 0-10 cm in three coastal ecosystems: coastal sand sediments, rocks and mangroves. Samples then isolated and screened to obtain bacteria that have the potential to degrade polyethylene. Selected bacteria were identified by biochemical physiology according to the method of Cappuccino and Sherman and classified to genus level according to Bergey's Manual of Determinative Bacteriology and Bergey's Manual of Systematic Bacteriology. The results showed that three genera of bacteria had high polyethylene degradation potential with the speed of degradation: Enterobacteriaceae 0.0091%; Moraxella spp. 0.0066%; and Pseudomonas spp. 0.0076% per week.
Efek Probiotik EM4 pada Sistem Akuaponik terhadap Pertumbuhan, dan Mortalitas Ikan Guppy, serta Pertumbuhan Tanaman Mint Dimas Andre Adi Wibowo; Sucahyo Sucahyo; Djohan Djohan
Bioeksperimen: Jurnal Penelitian Biologi Vol 9, No 1: March 2023
Publisher : Universitas Muhammadiyah Surakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23917/bioeksperimen.v9i1.19330

Abstract

The determination of antioxidant and lead content of hemiparasite Dendrophthoe vitellina (F. Muell) Tiegh on Nutmeg Anna Helena Sabandar; Sri Kasmiyati; Djohan Djohan
Pharmaciana Vol 13, No 3 (2023): Pharmaciana
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/pharmaciana.v13i3.26780

Abstract

 Mistletoe, a parasitic plant growing on nutmeg trees, is conventionally perceived as a parasitic entity with limited regard for its potential medicinal value. On the other hand, mistletoe has a remarkable potential source of valuable medicinal compounds, particularly in traditional healthcare, due to its secondary metabolites such as flavonoid, phenolic, ascorbic acid, and antioxidant activity. Nevertheless, both the host tree and the environment, like Pb, influence the adaptive responses of secondary metabolites. This study aimed to determine the secondary metabolites, such as flavonoids, phenolics, ascorbic acid, antioxidant activity, and Pb content in the leaves of D. vitellina and nutmeg (M. fragrans). The samples were obtained via maceration using ethanol. The spectrophotometric analysis method was used to measure several parameters, using particular reagents for phenolic compounds using Folin-Ciocalteu, flavonoids using AlCl3, and ascorbic acid using sulfosalicylic acid), antioxidant activity using DPPH, and Pb using the AAS method. The results indicated that D. vitellina possesses a higher concentration of flavonoid and phenolic compounds, followed by 3.36 ± 1.92 % (w/w) and 18.45 ± 2.35 % (w/w) respectively. Conversely, nutmeg had a significant ascorbic acid concentration of 3.99 ± 4.38 % (w/w). The significant presence of phenolics and flavonoids had a crucial role in the antioxidant activity seen in D. vitellina, which exhibited exceptionally potent antioxidant properties. All samples contain Pb, ranging from 0.00001–0.00021 % (w/w), within the maximum allowable limits. Therefore, mistletoe is notable for being a reliable and encouraging plant species that can provide a natural supply of antioxidants and be safely used in traditional medicine.
Pelatihan Pembuatan Produk Olahan Sampah Organik Kepada Ibu-Ibu PKK Dliko Indah, Blotongan, Salatiga Susanti P. Hastuti; Sucahyo Sucahyo; Rully A. Nugroho; Agna S. Krave; Andreas B.A. Sukmana; V. I. Meitiniarti; Sri Kasmiyati; Elizabeth B.E. Kristiani; Natalia R. Keliat; Desti C. Cahyaningrum; Risya P. Situmorang; Marisa C. Tapilouw; Djohan Djohan; Risky H. Poluan; Cocok A.M. Berutu; Marchella G. Putricia; Easter G. Tuandali; Ciputra S. Mangesa; Shabrina R.A. Fernanda; Imel T.Y. Zebua
JURNAL PENGABDIAN PAPUA Vol 10 No 2 (2026)
Publisher : LPPM Uncen

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31957/jpp.v10i2.5840

Abstract

Knowledge regarding the handling of waste generated by human activities—and familiarity with the associated technologies—has not yet widely reached housewives. This is due to constraints on their time and energy, as well as a lack of hands-on exposure to these technologies within the household setting. Public understanding regarding the composition of waste (both dry and wet) remains limited, and there is a prevailing tendency—particularly in terms of attitudes and behavior—to rely on the government for waste management. Although the potential for utilizing organic waste is immense, implementation at the community level faces obstacles such as regulatory issues, technological limitations, and low collective awareness. Therefore, it is urgent to enhance knowledge and develop technologies for converting organic waste into value-added products, especially for housewives who deal with organic waste generation on a daily basis. The partners for this activity are 65 housewives who are members of the PKK (Family Welfare Empowerment) group in RT01/RWXI Dliko Indah, Blotongan, Salatiga. The implementation team comprises fifteen lecturers and five students from the Biology study program. The program is executed in two stages: a preparation phase and a product production phase. The preparation phase involves initial planning by the community service team in coordination with the partners. The product production phase entails material preparation and the creation of products such as compost, liquid organic fertilizer (POC), and eco-enzymes. These activities include hands-on practice, followed by continuous monitoring to evaluate the program's success. 
EFFECTIVENESS OF AQUAPARTBOX NATURAL SCIENCE IIC IN SUBSTANCE AND PARTICLE MODEL SUB MATERIAL CLASS 7 Yohanes Advent Susprimadhi; Marisa Christina Tapilouw; Djohan Djohan
SPEKTRA: Jurnal Kajian Pendidikan Sains Vol. 11 No. 1 (2025): SPEKTRA: Jurnal Kajian Pendidikan Sains
Publisher : Physics Education Study Program, Faculty of Education and Teacher Training, UNSIQ

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32699/spektra.v11i1.8943

Abstract

Laboratory work by using laboratory equipment. It is important to develop simple and affordable laboratory equipment for learning natural science. It is expected that the learning laboratory work will increase from 15% to almost all learners achieve. Due to this condition, students could not understand the phenomenon of natural science. Therefore, the purpose of the research 1) to design a tool for laboratory work, AquapartBox IIC 2) to measure the chances of student achievement with interaction of AquapartBox IIC. IIC was developed using the ADDIE model development research method (Analyze, Design, Development, Implementation, and Evaluation). Based on the analysis, there is potential for developing natural science IIC instructional media. At the design stage, a sketch was produced which became the basis for the development of the IIC. At the development stage, the AquapartBox IIC and learning tools were validated and tested. The validators consist of a biology lecturer, a physics lecturer and a science teacher. At this stage students are given a pre-test and post-test. The pretest score obtained was 80.14 and the posttest score obtained was 87.6. This second value is included in calculating the NGain calculation, the N-Gain obtained is 0.38. Next, a final evaluation was carried out by teachers (4.15) and students (3.89) which showed that IIC was effective.
Co-Authors Agna S. Krave Andreas B.A. Sukmana Anggara Mahardika Anna Helena Sabandar Antonius Budi Susanto Awalina Choirunnisa Rachmawati Bibin Bintang Andriana Ciputra S. Mangesa Cocok A.M. Berutu Desti C. Cahyaningrum Dimas Andre Adi Wibowo Easter G. Tuandali Elizabeth B.E. Kristiani Imel T.Y. Zebua Marchella G. Putricia Marisa Christina Tapilouw Natalia R. Keliat Risky H. Poluan Risya P. Situmorang Rully A. Nugroho Shabrina R.A. Fernanda Sri Kasmiyati Sri Kasmiyati Sucahyo Susanti P. Hastuti V. I. Meitiniarti Yohanes Advent Susprimadhi