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Lecanicillium and Verticillium species from Indonesia and Japan including three new species saksenae) are proposed from the fungi isolated from epiphytic and subterranean arthropods collected in East Kalimantan.Abstract Forty-six Lecanicillium strains and one Verticillium strain were isolated from subterranean and epiphytic arthropods, soil, and other sources collected in Indonesia and Japan. These strains were identifi ed as nine Lecanicillium and one Verticillium species including six undescribed species based on light microscopy and the sequences of the ITS-1 and ITS-2 regions including 5.8S ribosomal DNA. Four of the ten species (L. araneicola, L. kalimantanense, Lecanicillium sp. 4, and V. indonesiacum) were recovered from Indonesia, fi ve of the ten (L. attenuatum, L. fusisporum, L. psalliotae, Lecanicillium sp. 1, and Lecanicillium sp. 3) were from Japan, and L. saksenae was from both countries. In this article, new species (L. araneicola, L. kalimantanense, and V. indonesiacum) and a new combination (L.

ABSTRAKBakteri Aeromonas hydrophila bersifat patogen mengakibatkan kematian sebanyak 50% pada ikan nila di keramba jaring apung. Penelitian ini bertujuan untuk meneliti patogenisitas dan virulensi dari dua enzim dan satu toksin haemolisin yang dihasilkan oleh A. hydrophila pada ikan nila yang sehat. Analisis LC-50 menggunakan metode Dragsted Bahrens menghasilkan nilai 4,9 x 10 6 cfu/mL. Virulensi A. hydrophila diuji menggunakan metode Postulat Koch pada ikan nila sehat menyebabkan tubuh menjadi kemerah-merahan, perdarahan pada permukaan tubuh dan luka borok yang akhirnya menyebabkan kematian.

This study's aim was to determine the identity of antibacterial compounds produced by Pseudomonas aeruginosa strain UICC B-40 and describe the antibacterial compounds' mechanisms of action for damaging pathogenic bacteria cells. Isolation and identification of the compounds were carried out using thin layer chromatography (TLC), nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography mass spectrometry (LC-MS) analyses. Antibacterial activity was assayed via minimum inhibitory concentration (MIC) and the antibacterial compound mechanism was observed morphologically through scanning electron microscopy (SEM). This study successfully identified the (2E,5E)-phenyltetradeca-2,5-dienoate antibacterial compound (molecular weight 300 g/mol), composed of a phenolic ester, fatty acid and long chain of aliphatic group structures. MIC values for this compound were determined at 62.5 μg/ml against Staphylococcus aureus strain ATCC 25923. The mechanism of the compound involved breaking down the bacterial cell walls through the lysis process. The (2E,5E)-phenyltetradeca-2,5-dienoate compound exhibited inhibitory activity on the growth of Gram-positive bacteria.

Abstract. Dewijanti ID, Mangunwardoyo W, Dwiranti A, Hanafi M, Artanti N. 2020. Short communication: Effects of the various source areas of Indonesian bay leaves (Syzygium polyanthum) on chemical content and antidiabetic activity. Biodiversitas 21: 1190-1195. Bay leaves (Syzygium polyanthum (Wight) Walp) are from an Indonesian plant species belonging to the Myrtaceae family. The Indonesian name for this plant is salam; it is found in Sumatra, Kalimantan, and the Java Islands. Its leaves are the part of the plant commonly used. Salam leaves are usually consumed by people as a food flavoring, but are also used as a traditional antidiabetic medicine. The purpose of this study was to discover the effects of salam leaves’ origins on their chemical content and antidiabetic activity. For this reason, salam leaf samples were collected from three different provinces in Java (West Java, Central Java, and East Java). The samples were extracted by boiling in water. Phytochemical screening, chemical analysis using TLC, HPLC, LC-MSMS, and FTIR, and antidiabetic in vitro testing using alpha-glucosidase inhibition methods were conducted on the salam leaves’ water extracts. The results showed that salam leaf extracts from all three provinces contained quercetin. However, the salam originating from East Java also contained coniferin, the salam from Central Java contained juncusol, and the salam from West Java contained retucine. The salam leaves originating from East Java showed the lowest antidiabetic activity, whereas salam leaf extract showed significantly higher antidiabetic activity. As conclusion, a plant’s growth origin affects its chemical content and antidiabetic activity.