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Effect of mulch and liquid organic fertilizer on shallot production (Allium cepa)
Full text linkShallot (Allium cepa) is an economically valuable and highly nutritious crop whose productivity can be increased through optimal cultivation practices. This study investigated the combined effects of mulch and liquid organic fertilizer (LOF) on onion yield and performance. A factorial randomized block design (RCBD) was used consisting of two factors, namely mulch type (no mulch, black and silver plastic mulch, rice husk mulch, and shallot skin mulch) and LOF dosage (no LOF, 1,000 L/ha, and 1,500 L/ha). Data were analyzed using Least Significant Difference (LSD) and Duncan's Multiple Range Test (DMRT) at = 5%. The application of rice husk mulch and LOF at a dose of 1,500 L/ha resulted in the highest number of bulbs, bulb diameter, wet weight, dry weight, soil microbial population, and peroxidase enzyme activity among all treatments. This study demonstrates that rice husk mulch and LOF at a dose of 1,500 L/ha can significantly enhance shallot production. Additionally, the findings indicate that the use of rice husk mulch and LOF at a dose of 1,500 L/ha can boost soil microbial population and increase peroxidase enzyme activity
Biodegradation of diisobutyl phthalate using fungi plastisphere isolated from plastic waste in mangrove Kadilangu area
Full text linkDiisobutyl phthalate, an additive in plastic production belonging to the group of xenobiotic substances, has a negative impact on human health, especially on the reproductive system. In Indonesia, the presence of plastisphere fungi is often used as a degrading agent for xenobiotic substances. Plastisphere fungi show enzymatic activity to degrade xenobiotic substances but have not been widely studied. Therefore, this research aims to assess the ability of several genera of plastisphere fungi to degrade diisobutyl phthalate and evaluate their enzyme activity and their tolerance under heavy metal stress. The method for determining degradation used an UV-VIS spectrophotometer at wavelength of 362 nm, fungal identification used profile matching method, the presence of oxidoreductase enzymes in fungi was assessed using qualitative method with selective media (ABTS 200 mg/L, phenol red 50 mg/L, and methylene blue 4%), and their tolerance to heavy metals at a concentration of 50 ppm was analyzed using tolerance index method. The identification results of fungi come from the genera Acremonium and Aspergillus, and tolerance index analysis revealed that these genera have high tolerance to very tolerant (0.91-1.23) to the metals (copper, chromium, and lead) induced stress. Evaluation of oxidoreductase enzyme activity showed that Aspergillus from isolate LT2(1) had laccase, lignin peroxidase, and manganese peroxidase enzymes. Analysis of diisobutyl phthalate degradation using an UV-VIS spectrophotometer with wavelength of 362 nm showed that all isolates were able to degrade diisobutyl phthalate within 14 days of incubation period at room temperature (20oC-23oC) under copper-induced stress, with the highest isolate degrading diisobutyl phthalate is Aspergillus LT2(1) (75.57%), followed by Acremonium PK2(2) (60.65%), and Aspergillus HT3(2) (36.79%). Based on these findings, it can be concluded that Aspergillus LT2(1) shows the best agent to degrade diisobutyl phthalate because it has the ability to regulate the flow of nutrients and energy through the structure of hyphae and mycelial tissues and produces oxidoreductase enzymes that are able to degrade recalcitrant compounds
Assessing the water quality in the Timbalun river watershed, Padang City, West Sumatra, Indonesia
Full text linkThe purpose of this study is to assess water quality, specifically pH, conductivity, total dissolved solids (TDS), salinity, and turbidity. The research utilizes quantitative methods and covers 15 sampling points across the Timbalun River basin in Padang City, West Sumatra, Indonesia. Samples were measured based on several parameters, with three repetitions for accuracy. The testing took place from August to September 2024. The results showed that some water quality parameters, such as pH and total dissolved solids, met the standards outlined by Ministry of Health Regulation No. 2 of 2023. However, other parameters, including salinity, conductivity, and turbidity, did not meet the specified thresholds. It is essential to implement treatment measures to ensure the water meets the required standards for its intended use
Oral glucose tolerance assay of extract from Mangifera foetida l. and Pandanus amaryllifolius roxb. leaves
Full text linkThis study examines the potential antidiabetic activity of a combination of Mangifera foetida L. and Pandanus amaryllifolius Roxb. leaves. Mangifera leaves contain a compound called mangiferin, which acts as an antidiabetic and antioxidant. On the other hand, Pandanus leaves, are rich in terpenoids and steroids that also possess anti-diabetic effects. An Oral Glucose Tolerance Test (OGTT) was conducted on male mice of the Babl/c strain to assess the antidiabetic effects. The test involved administering a combination of ethanolic leaf extracts from Mangifera foetida L. and Pandanus amaryllifolius Roxb. in a 1:1 ratio. The study followed a pre-test design with a control group, comprising six treatment groups, each consisting of four male mice. The groups were described as follows: Group 1 was served as the normal group without any treatment. Groups II-IV received single extracts or combinations of extracts at doses of 62.5 mg/200g BW, 125 mg/200g BW, and 250 mg/200g BW. Group V acted as the positive control and was given oral glucose and glibenclamide at a dose of 0.09 mg/200g BW. Group VI was served as the negative control, receiving oral glucose and distilled water. The group that exhibited the highest percentage of decreased blood sugar levels was the one given oral glucose at a dose of 0.078g/20g BW of mice, along with the combination of Mangifera foetida L. and Pandanus amaryllifolius Roxb. leaves extract (1:1) at a dose of 35 mg/20g BW. This group demonstrated a decrease of 71.985 4.858 in blood glucose levels. The ANOVA analysis confirmed that the percentage decrease in blood sugar levels was significantly different from the positive control, indicating a higher effectiveness of the combination treatment in reducing blood glucose levels than the positive control
Phytochemical screening and antibacterial activity testing of n-hexane extract from Barringtonia asiatica seeds
No full textBarringtonia asiatica, a marine plant belonging to the Lecythidaceae family, exhibits bioactivity in all parts of the plant. In the Simeulue region, the seeds of this plant are used for fish trapping. The polar extracts of B. asiatica seeds has shown antibacterial activity, but the non-polar extracts has not been studied yet. Therefore, this study aimed to determine the secondary metabolites of B. asiatica using a non-polar solvent (n-hexane) and evaluate its activity against Gram-positive and Gram-negative bacteria. The extraction method employed using soxhlet extraction, and the antibacterial activity was determined using the Kirby-Bauer method. The presence of secondary metabolites in the B. asiatica seed extract was assessed using phytochemical tests, and its chemical composition was analyzed using Gas Chromatography Mass Spectrophotometry (GC-MS). The yield of n-hexane extract from B. asiatica seeds was 1.7%, and the phytochemical analysis revealed that the B. asiatica seeds n-hexane extract contains only terpenoids compounds. The B. asistica seeds n-hexane extract at concentration of 10% (w/v) showed the highest zone of inhibition against Staphylococcus aureus (9.3 mm) followed by Escherichia coli (9,9 mm). The GC-MS analysis showed that B. asiatica seeds n-hexane extract contains Guaiene, Guaiene, Ledene, 9,12-Octadecadienoic acid, and Ethyl linoleate. Based on these findings, it can be concluded that B. asiatica seed's n-hexane extract exhibited antibacterial activity against S. aureus and E. coli
Genetic diversity of Ulva lactuca from the intertidal zone in Ulee Lheue beach Aceh, Indonesia
Full text linkUlee Lheue Beach in Banda Aceh was developed for tourism. The macroalgae and seaweed species found in this area have been widespread but never exploited. Among these species is the green seaweed, Ulva lactuca, commonly known as sea lettuce. The physiological variations and genetic features of the seaweed can be attributed to the variations in the coastal environment. This study aims to describe the molecular identity of the genetic diversity of U. lactuca from the intertidal zone at Ulee Lheue Beach. The development of molecular biotechnology has enabled identification the gene expression through genomic DNA to PCR amplification. Genetic distance was determined using UPGMA. The results from 600-bp fragments were analyze the genetic diversity. A total of 15 (31%) expression identified as polymorphic (0.500). Heterozygosity (He) and allelic differential (Na) diversity were found of 1.5003.000. The highest PIC was observed in the rbcL1, with a correlation between subpopulations of 0.459. PCR amplification using the degenerate primer rbcL1 produced fragments ranging from 300 to 460 bp, whereas the expression of UL2 was detected at 448 and 500 bp using the rbcL2 primer. The phylogenetic identify are shown two (2) clusters. The populations of UL1, UL3, and UL4 were found a close relationship. Furthermore, the UL1 and UL2 populations were further divided into distinct clusters but related to the main branch of UL3. Based on this research, the concern of U. lactuca species for industrial and biotechnology destinations, we can describe a suitable method for obtaining he genetic distances between species
On locating-chromatic number of helm graph H_m FOR 10m28
No full textLet G = (V,E) be a connected graph and c be a k-coloring of G. The color class S_i of G is a set of vertices given color i, for 1 i k. Let = {S_1,S_2,,S_k} be an ordered partition of V(G). The color code of a vertex v (element) V(G) is defined as the ordered k--tuplec_ (v)=(d(v,S_1),d(v,S_2),...,d(v,S_k)),where d(v,S_i) = min{d(v,x)| x (element) S_i} for 1 i k. If distinct vertices have distinct color codes, then c is called a locating-coloring of G. The locating-chromatic number _L (G) is the minimum number of colors in a locating-coloring of G. This paper discusses the locating-chromatic number of helm graph H_m for 10 m 28. Helm graph H_m is constructed by adding some leaves to the corresponding vertices of wheels W_m, for m 3
BHF and copula models in small area estimation for household per capita expenditure in Bogor District
Full text linkSmall area statistics are required when the sample size is small to produce estimates with adequate precision. The assumptions underlying Battese Harter Fuller (BHF) unit-level models may often be unrealistic in some applications. Copula is an alternative approach when the assumptions are violated. This research discusses the performance of BHF and Copula in small area estimation (SAE) for estimating household per capita expenditure in sub-district levels. This study presents household per capita expenditure, which has a skewed distribution. Due to the fact that the data contains outliers, an appropriate method to handle outliers is also considered. In this research, the Gaussian and the Clayton Copulas are used. The results showed that the performance of BHF was better than Gaussian and Clayton Copulas, as indicated by small root mean square error (RMSE) with an average of 1.14, while the average RMSE of Gaussian copula was 2.71 and Clayton copula was 2.63. Furthermore, the coefficient of variation (CV) of BHF was also smaller compared to Gaussian and Clayton Copulas, and the resulting estimates can be categorized as reliable based on the CV of less than 25%
Preparation and characterization of physical properties of molded pulp from empty fruit bunches of oil palm
Full text linkThis research aims to determine the impact of pretreatment on empty fruit bunches (EFB) of palm oil fibers before the pulping process on the quality of the molded pulp produced. The study includes EFB fiber pretreatment processes, pulp production, pulp molding, physical characteristic analysis, and molded pulp performance evaluation. The pulp production process involves acid-base hydrolysis reactions. The produced molded pulp is done manually. Characterization of the molded pulp includes measurements of paper grammage, thickness, density, and moisture content. The characteristics of pulp produced from pretreated EFB fibers are as follows: an average grammage value of 415.48 g/m, paper thickness of 1.53 mm, water absorption capacity of 13.33-33.33%, density of paper of 0,026 x 106 - 0,027 x 106 g/m3, and a smooth surface morphology. Meanwhile, the characteristics of pulp produced from without pretreatment EFB fibers include an average grammage value of 372.18 g/m, paper thickness of 0.77 mm, water absorption capacity of 20.34-43.21%, density of paper of 0,004 x 106 - 0,008 x 106 g/m3, and a rough surface morphology due to pores on the fiber surface
On the dynamics of spring-pendulum system: an overview of configuration space and phase space
Full text linkThe dynamics of the spring-pendulum system with two degrees of freedom were studied. The motion of this system is restricted to be in a vertical plane so that the chosen generalized coordinates are the increased length of the spring and the swing angle of pendulum . Hamiltonian of the system is obtained from the Legendre transformation of Lagrangian. Hamiltons equation yields four differential equations that represent the dynamic of the system. The obtained results were visualized in configuration space and phase space trajectories. It is shown that generally the greater the initial swing angle, the more complex pattern will occur followed by the appearance of chaotic phenomena