Gadjah Mada University

About: Gadjah Mada University is a education organization based out in Yogyakarta, Indonesia. It is known for research contribution in the topics: Population & Adsorption. The organization has 17307 authors who have published 21389 publications receiving 116561 citations. The organization is also known as: University of Gajah Mada & Universitas Gadjah Mada.

Improvement of biogas production from orange peel waste by leaching of Limonene

Abstract: Limonene is present in orange peel wastes and is known as an antimicrobial agent, which impedes biogas production when digesting the peels. In this work, pretreatment of the peels to remove limonene under mild condition was proposed by leaching of limonene using hexane as solvent. The pretreatments were carried out with homogenized or chopped orange peel at 20–40°C with orange peel waste and hexane ratio (w/v) ranging from 1 : 2 to 1 : 12 for 10 to 300 min. The pretreated peels were then digested in batch reactors for 33 days. The highest biogas production was achieved by treating chopped orange peel waste and hexane ratio of 12 : 1 at 20°C for 10 min corresponding to more than threefold increase of biogas production from 0.061 to 0.217 m3 methane/kg VS. The solvent recovery was 90% using vacuum filtration and needs further separation using evaporation. The hexane residue in the peel had a negative impact on biogas production as shown by 28.6% reduction of methane and lower methane production of pretreated orange peel waste in semicontinuous digestion system compared to that of untreated peel.

Assessment of ecosystem services in homegarden systems in Indonesia, Sri Lanka, and Vietnam

Abstract: Numerous studies have been conducted on homegarden systems by researchers from different disciplines and countries, but most of them focus on ecological structure or specific ecosystem services in a selected study area. Few studies take a comprehensive look at the ecosystem services provided by homegardens, especially on a regional scale. This paper shows how these homegardens are ecologically, socially, and economically diversified and how beneficial they are to human well-being as ecosystem services. It also investigates the impacts of drivers on homegarden systems in rural areas in three countries. These studies involved comprehensive literature reviews and field survey along with a framework of the Millennium Ecosystem Assessment. Four types of ecosystem services—provision, regulation, cultural, and support—were assessed and compared. We found that traditional homegardens maintain high ecosystem diversity especially in rural areas; however, recent socio-economic changes are converting subsistence-oriented homegardens into commercial ones. Future challenges for further research include how to enhance the resilience of homegarden systems against socioeconomic and global climate changes by integrating traditional homegarden systems, modern technology, and the global economy.

Structural Changes of Oil Palm Empty Fruit Bunch (OPEFB) after Fungal and Phosphoric Acid Pretreatment

Abstract: Oil palm empty fruit bunch (OPEFB) was pretreated using white-rot fungus Pleurotus floridanus, phosphoric acid or their combination, and the results were evaluated based on the biomass components, and its structural and morphological changes. The carbohydrate losses after fungal, phosphoric acid, and fungal followed by phosphoric acid pretreatments were 7.89%, 35.65%, and 33.77%, respectively. The pretreatments changed the hydrogen bonds of cellulose and linkages between lignin and carbohydrate, which is associated with crystallinity of cellulose of OPEFB. Lateral Order Index (LOI) of OPEFB with no pretreatment, with fungal, phosphoric acid, and fungal followed by phosphoric acid pretreatments were 2.77, 1.42, 0.67, and 0.60, respectively. Phosphoric acid pretreatment showed morphological changes of OPEFB, indicated by the damage of fibre structure into smaller particle size. The fungal-, phosphoric acid-, and fungal followed by phosphoric acid pretreatments have improved the digestibility of OPEFB's cellulose by 4, 6.3, and 7.4 folds, respectively.

Plasmodium malariae Infection Associated with a High Burden of Anemia: A Hospital-Based Surveillance Study.

Abstract: Background Plasmodium malariae is a slow-growing parasite with a wide geographic distribution. Although generally regarded as a benign cause of malaria, it has been associated with nephrotic syndrome, particularly in young children, and can persist in the host for years. Morbidity associated with P. malariae infection has received relatively little attention, and the risk of P. malariae-associated nephrotic syndrome is unknown. Methodology/Principal Findings We used data from a very large hospital-based surveillance system incorporating information on clinical diagnoses, blood cell parameters and treatment to describe the demographic distribution, morbidity and mortality associated with P. malariae infection in southern Papua, Indonesia. Between April 2004 and December 2013 there were 1,054,674 patient presentations to Mitra Masyarakat Hospital of which 196,380 (18.6%) were associated with malaria and 5,097 were with P. malariae infection (constituting 2.6% of all malaria cases). The proportion of malaria cases attributable to P. malariae increased with age from 0.9% for patients under one year old to 3.1% for patients older than 15 years. Overall, 8.5% of patients with P. malariae infection required admission to hospital and the median length of stay for these patients was 2.5 days (Interquartile Range: 2.0–4.0 days). Patients with P. malariae infection had a lower mean hemoglobin concentration (9.0g/dL) than patients with P. falciparum (9.5g/dL), P. vivax (9.6g/dL) and mixed species infections (9.3g/dL). There were four cases of nephrotic syndrome recorded in patients with P. malariae infection, three of which were in children younger than 5 years old, giving a risk in this age group of 0.47% (95% Confidence Interval; 0.10% to 1.4%). Overall, 2.4% (n = 16) of patients hospitalized with P. malariae infection subsequently died in hospital, similar to the proportions for the other endemic Plasmodium species (range: 0% for P. ovale to 1.6% for P. falciparum). Conclusions/Significance Plasmodium malariae infection is relatively uncommon in Papua, Indonesia but is associated with significant morbidity from anemia and a similar risk of mortality to patients hospitalized with P. falciparum and P. vivax infection. In our large hospital database, one in 200 children under the age of 5 years with P. malariae infection were recorded as having nephrotic syndrome.

Effect of natural and Lactobacillus plantarum fermentation on in-vitro protein and starch digestibilities of sorghum flour

Abstract: Sorghum flour was either naturally fermented or inoculated by Lactobacillus plantarum at 37 1C for 36 h. Changes in bacteria, pH, acidity, protein, in-vitro protein digestibility (IVPD), starch content and in-vitro starch digestibility (IVSD) were monitored every 4 h. Pasting properties were carried out only in the native sorghum flour, and two types of fermented flour with highest improved IVPD and IVSD. Results showed that both fermentation types increased total bacteria by 5 log, lactic acid bacteria (LAB) by 5 log, and proteolytic bacteria by 2-3 log cycles. The pH decreased from 5 to 3 with the increased of titratable acidity. Natural and L. plantarum fermentations for 36 h improved IVPD by 46.89% and 92.08%, respectively, and increased IVSD by 71.48% and 65.63%, respectively. The highest IVSD enhancement (78.69%) was shown by L. plantarum for 28 h. Fermentation decreased gelatinization temperature (GT), increased peak viscosity (PV) and hot paste viscosity (HPV). The greatest improved viscosities were shown by L. plantarum.