KEANEKARAGAMAN ORGANISME PADA RHIZOSFER GULMA SIAM DI LAHAN VULKANIK, PESISIR, DAN KARST

Penelitian ini bertujuan untuk membandingkan kondisi edafik, hubungan antara kondisi edafik dan keanekaragaman organisme tanah, serta perbedaan keanekaragaman organisme tanah pada berbagai ekosistem rhizosfer gulma Siam (Chromolaena odorata) yang tumbuh di lahan vulkanik, pesisir, dan karst. Penelitian dilakukan dengan mengambil sampel tanah dari ekosistem rhizosfer gulma Siam di lahan vulkanik, karst, dan pesisir Daerah Istimewa Yogyakarta; mengamati komposisi organisme tanah di laboratorium, yaitu collembola, nematoda, dan mikoriza. Hasil penelitian menunjukkan bahwa tanah pada rhizosfer gulma Siam yang tumbuh di lahan karst menunjukkan tingkat kesuburan tertinggi yang ditunjukkan oleh kandungan N, K, dan C-organik tanah, sedangkan tanah pesisir memiliki kandungan P tertinggi. Tekstur tanah pada rhizosfer gulma Siam lebih berpengaruh terhadap keanekaragaman organisme tanah dibandingkan kandungan hara tanah dan sifat tanah lainnya yang diteliti. Keragaman organisme tanah rhizosfer gulma Siam lebih besar di lahan pesisir dibandingkan di lahan karst dan vulkanik. Implikasi dari hasil tersebut adalah bahwa tanah dengan tekstur berpasir akan lebih bermanfaat bagi pertumbuhan gulma Siam dengan keanekaragaman organisme rhizosfer yang lebih tinggi.ORGANISM DIVERSITY IN THE RHIZOSPHERE OF SIAM WEEDS IN VOLCANIC, COASTAL AND KARST LANDThe research aims to compare the edaphic condition, the relationship between the edaphic condition and soil organism diversity, and the differences of soil organism diversity in different rhizosphere ecosystems of Siam weed growing in volcanic, coastal and karts areas. The research was conducted by taking soil samples from the Siam weed rhizosphere ecosystems in volcanic, karst and coastal areas of the Special Region of Yogyakarta and observing the composition of the soil organisms in the laboratory, including collembola, nematode, and mycorrhiza. The results find that soil from rhizosphere of Siam weed growing in karst area shows the highest level of fertility indicated by the N, K, and C-organic contents of the soil, whereas soil from coastal area has the highest P content. Soil texture in the rhizosphere of Siam weed has more effect on the diversity of soil organisms than the soil nutrient content and other soil properties investigated. The diversity of soil organisms of Siam weed rhizosphere is greater in coastal area than those in karst and volcanic areas. The implication of the results is that soil with a sandy texture will be more beneficial for the growth of Siam weed with a higher diversity of rhizosphere organisms

Antifungal Liposomes Directed by Dectin-2 Offer a Promising Therapeutic Option for Pulmonary Aspergillosis

ABSTRACT Invasive fungal diseases cause millions of deaths each year. There are currently approximately 300,000 acute cases of aspergillosis, most of which result from a pulmonary infection of immunocompromised patients by the common soil organism and opportunistic pathogen Aspergillus fumigatus. Patients are treated with antifungal drugs, such as amphotericin B (AmB). However, AmB has serious limitations due to human organ toxicity. AmB is slightly less toxic if loaded in liposomes, such as AmBisome or AmB-loaded liposomes (AmB-LLs). Even with antifungal therapy, recurrent infections are common, and 1-year fatality rates may exceed 50%. We have previously shown that coating AmB-LLs with the extracellular oligomannan-binding domain of the C-type lectin receptor Dectin-2 (DEC2-AmB-LLs) effectively targets DEC2-AmB-LLs to cell walls, exopolysaccharide matrices, and biofilms of fungal pathogens in vitro. In vitro, DEC2-AmB-LLs reduce the effective dose of AmB for 95% inhibition and killing of A. fumigatus 10-fold compared to that of untargeted AmB-LLs. Herein we tested the antifungal activity of DEC2-AmB-LLs relative to that of untargeted AmB-LLs in immunosuppressed mice with pulmonary aspergillosis. Remarkably, DEC2-AmB-LLs bound 30-fold more efficiently to A. fumigatus at sites of infection in the lungs. Furthermore, Dectin-2-targeted liposomes delivering AmB at a dose of 0.2 mg/kg of body weight significantly reduced the fungal burden in lungs compared to results with untargeted AmB-LLs at 0.2 mg/kg and micellar voriconazole at 20 mg/kg and prolonged mouse survival. By dramatically increasing the efficacy of antifungal drugs at low doses, targeted liposomes have the potential to create a new clinical paradigm to treat diverse fungal diseases. IMPORTANCE Invasive aspergillosis (IA) generally results from a pulmonary infection of immunocompromised patients by the common soil organism and opportunistic pathogen Aspergillus fumigatus. The susceptible population has expanded rapidly due to the increased number of cancer patients with immunocompromising chemotherapy and transplant patients taking immunosuppressants. Patients are treated with antifungals, such as liposomal amphotericin B, with per-patient costs exceeding $50,000 in the United States. However, AmB has serious side effects due to host toxicity, which limits its usage and contributes to the lack of fungal clearance in patients at safe doses. Fifty percent of IA patients die within a year. Herein, we employed liposomal amphotericin B coated with the innate immune receptor Dectin-2 to direct antifungals specifically to the fungal pathogen. Using two mouse models of pulmonary aspergillosis, we demonstrate that Dectin-2-targeted delivery of amphotericin B to A. fumigatus resulted in remarkably higher efficacy than that of the untargeted antifungal formulations.

Study on Abundance and Distribution Pattern of Collembola on Three Types of Land Utilizations in Banjar Regency, South Kalimantan

Collembola is one of soil organism which classified as mesofauna. This reseach is aims to study the abundance and distribution patterns of Collembola on three types of land utilization in Banjar District, South Kalimantan Province. This research was conducted on April 2020 by using a purposive sampling method. Based on results of Collembola identification obtained at the sampling location, there are 12 genera, 6 families, and 2 orders of Collembola. The highest abundance is found in oil palm plantations. While the Collembola distribution pattern on the three types of land clearing is the same, which is clustering. The results of this study are expected to provide information on the study of abundance and distribution patterns of Collembola in South Kalimantan Province related to environmental factors also help in carrying out sustainable ecosystem development.