Judul: Aktivitas Antibakteri dan Antikanker Plantarisin E dari Lactococcus lactis terhadap Enteropathogenic Escherichia coli K1.1 dan Sel Human Cervical Carcinoma (HeLa).
Abstrak: Bakteriosin adalah senyawa antibakteri yang disintesis dalam ribosom dan diproduksi oleh bakteri sebagai mekanisme pertahanan diri terhadap lingkungannya. Bakteriosin bersifat alami, tidak beracun dan tidak meninggalkan residu pada tubuh. Bakteriosin memiliki potensi besar untuk terapi medis, probiotik, serta sebagai pengawet makanan dan pakan. Bakteriosin Plantarisin E diproduksi melalui inang yang bersifat aman pangan yaitu Lactococcus lactis. Tahapan pemurnian Pln E dilakukan melalui beberapa tahap, yaitu pengendapan dengan ammonium sulfat, kromatografi filtrasi gel, penukar ion, dan interaksi hidrofobik. Perhitungan kemurnian menunjukkan tingkat kemurnian tertinggi didapatkan melalui tahap kromatografi interaksi hidrofobik dan tingkat kemurnian terendah didapatkan dari ekstrak kasar Pln E. Protein Pln E memiliki aktivitas antibakteri terhadap bakteri patogen dari kelompok Gram positif dan Gram negatif, yaitu Escherichia coli, Listeria monocytogenes, dan Staphylococcus aureus. Hasil uji sitotoksisitas terhadap sel HeLa menunjukkan penghambatan setelah pemberian ekstrak kasar Pln E dengan dosis 100 mg/mL dan hasil purifikasi Pln E dengan dosis 10 mg/mL. Nilai IC50 menunjukkan bahwa ekstrak kasar Pln E aman dikonsumsi di bawah dosis 107.453 mg/mL, sedangkan hasil purifikasi Pln E aman dikonsumsi di bawah dosis 11.613 mg/mL.
Keyword: aktivitas antibakteri, bakteriosin, Lactococcus lactis, pemurnian, sitotoksisitas, Pln E

Judul: Studi Sitotoksitas Komponen Intra Dan Ekstraseluler Lactobacillus Plantarum Iia-1a5 Dan Lactobacillus Acidophilus Iia-2b4 Terhadap Sel Hela
Abstrak: Bakteri asam laktat khususnya Lactobacillus diketahui berperan dalam mencegah beberapa penyakit yang diakibatkan oleh sel kanker. Tujuan dari penelitian ini adalah menganalisis sifat sitoksisitas dari bakteri asam laktat dengan menggunakan sel HeLa sebagai model sel kanker. Parameter yang diamati dalam penelitian ini yaitu kadar protein dan profil protein menngunakan SDS-PAGE, aktivitas BAL dengan menggunakan metode sitotoksik MTT assay, nilai IC50, dan morfologi sel hela yang telah diberi perlakuan dengan ekstrak bakter asam laktat. Hasil penelitian menunjukkan bahwa ekstrak intraseluler L. acidophilus IIA-2B4 mempunyai nilai penghambatan terbesar (74.16%) sedangkan ekstrak L. plantarum IIA-1A5 mempunyai nilai penghambatan kurang dari 50% Ektrak secara intraseluler menunjukkan adanya fenomena dose dependent response. Kesimpulan dari hasil penelitian ini yaitu Ekstrak intraseluler L. plantarum IIA-1A5 dan L. acidophilus IIA-2B4 dapat menghambat proliferasi sel kanker serviks HeLa sebesar ±70% dengan konsentrasi 200 μg/mL. Ekstrak L. acidophilus IIA-2B4 memiliki aktivitas sitoksisitas terbaik dengan nilai IC50 sebesar 120 μg/mL yang dapat diklasifikasikan kedalam kategori cukup toksik.
Keyword: Bakteri Asam Laktat, Proliferasi, Sel Kanker

Judul: Characteristic of Overshooting Top (OT) Based on  Himawari  8  Satellite  as  a  Convective  Cloud  Feature  that  Generates  Extreme Weather in the Java Island Region
Abstrak: Overshooting Top (OT) is a feature at the top of a convective cloud that is associated with extreme weather. Research on OT in tropical Indonesia is still very limited. The existence of geostationary satellites with wide area coverage and fast frequency observations is useful for observing the fast dynamics of the OT life cycle. Therefore, this study intends to analyze the relationship between OT and extreme weather, updraft and thermodynamic conditions of OT when extreme weather occurs, the best objective method for detecting OT in the day time and night time, and the spatiotemporal distribution of OT in the tropical region of Java Island during the 2018-2021 period. Based on visual analysis using visible channel and Himawari 8 sandwich products, 87% of extreme weather events in Java were accompanied by the appearance of OT. It indicates that the presence of the OT pattern is a convection cloud pattern or feature that is closely related to extreme weather events for the Java Island region. The existence of a time lag between the appearance of OT and extreme weather events on Java Island indicates that the OT of convection cloud can be used as a precursor or nowcasting for the appearance of extreme weather. Most of the convective cloud OT features during extreme weather events on Java Island have altitude that were only able to exceed the altitude of the equilibrium level and few were able to exceed the tropopause level of 9 km – 16 km. The difference in atmospheric conditions during extreme weather events on Java Island, which is in the tropics and subtropics, is a strong and unstable convective energy condition characterized by a larger CAPE, as well as unstable KI, LI, SI and TTI values. It is offset by kinematic factors in the form of a weak vertical wind shear (bulk wind shear 0-6 km) and a higher freezing point height. The difference between extreme weather events in the Java Island region and other tropical regions compared to subtropical regions is the strong updraft speed of convection clouds. The IRW Texture COMB algorithm based on the IRW-Texture Gradient modification and the COMB algorithm shows a significant increase in quality for detecting OT and non-OT pixels in Java. Rainy days with rainfall > 50 mm/day are very common in areas with an altitude of > 500 m. On the other hand, the level of convection activity which is indicated by the presence of OT and lightning is significantly reduced in this area. OT of convective clouds appear more frequently during the DJF season and less frequently during the JJA season. OT often appears during the day time and rarely at night time. Most OTs appear in the central part, away from the south and north coasts of Java Island during the day, while OTs that appear near the south and north coasts of Java Island can appear in the morning or afternoon.
Keyword: convective clouds, extreme weather, Overshooting Tops, Himawari 8 Satellite