JURNAL AGROTEKNOLOGI
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KARAKTERISTIK FISIKOKIMIA RICE PAPER DENGAN SUBSTITUSI TEPUNG PEKTIN ALBEDO SEMANGKA (Citrullus lanatus)
Edible rice paper is used for making fresh summer rolls (salad rolls) or fried spring rolls in Vietnamese cuisine, where the rice paper is called bánh tráng or bánh đa nem. Ingredients of the food rice paper include white rice flour, tapioca flour, salt, and water. However, in this study, watermelon albedo pectin flour was added to the formulation. The purpose of this study was to determine the concentration of pectin flour and the effect of watermelon albedo pectin addition on the physicochemical characteristics of rice paper. The addition of pectin flour can produce a product that is elastic, not easily torn, and translucent. The research method used a completely randomized design (CRD) with the research factor being the concentration of watermelon albedo pectin flour which consisted of 6 experimental levels and 4 replications. The concentrations of pectin used were 0.25%, 0.5%, 0.75%, 1%, 1.25%, and 1.5%. Data were analyzed using ANOVA (analysis of variance) and continued with duncan multiple range test (DMRT) at the level of 5%. The variables tested were water content, water activity and rehydration power. Based on the results of this study the addition of watermelon albedo pectin flour on rice paper as much as 1.25% was the best treatment, this was because the water content produced about 11.38% and the rehydration power about 233.27%. There was an increase in water content and water activity, but a decrease in rehydration power, however, the water content test showed that the pectin concentration had no significant effect on the physicochemical characteristics of rice paper. So that the concentration of watermelon albedo pectin only affects the water activity and rehydration power of rice paper.
Keywords: pectin, rice paper, watermelon albed
OPTIMASI KITOOLIGOSAKARIDA CANGKANG RAJUNGAN (Portunus pelagicus) MENGGUNAKAN ENZIM KITOSANASE DARI Bacillus sp.
Chitooligosaccharides (COS) are glycoprotein complex compounds derived from chitosan linked by 1,4 glucosidic bonds with chain lengths of 20 or less. Crab shell is a crustacean waste that contains 20-30% chitin as the basic material for making chitooligosaccharides. Chitooligosaccharide hydrolysis can be carried out enzymatically. Enzymatic hydrolysis is specific and controlled. Enzymes that can be used to hydrolyze chitosan into chitooligosaccharides are chitosanase enzymes. Chitosanase enzyme is a glycosyl hydrolase enzyme that catalyzes the hydrolysis of -1,4 glycosidic bonds of chitosan to produce low molecular weight chitooligosaccharides. One of the bacteria that produces chitosanase enzymes, namely Bacillus sp. The purpose of this study was to optimize the production of chitooligosaccharides by treating the enzyme concentration, hydrolysis time, and hydrolysis temperature. This research was conducted using a completely randomized design (CRD) with the following factors: enzyme concentration (0.5%, 1%, 1.5%, 2%, 2.5%) and hydrolysis temperature (30oC, 40oC, 50oC, 60oC, 70oC, 80oC) and time of hydrolysis (1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours and 8 hours). This enzyme works optimally at pH 4.5. The results showed that this chitosanase enzyme had optimum activity at a concentration of 2% (w/w) chitosan, a temperature of 50oC, and a hydrolysis time of 5 hours. The chitooligosaccharide has a reducing sugar content of 8.49 ± 0.38 mg/mL, a viscosity of 19.08 ± 0.01 cPs, and a molecular weight of 4.51 kDa.
Keywords: chitooligosaccharides, crab shells, chitosanase enzyme, hydrolysi
KARAKTERISTIK FISIK BUBUK KUNYIT (Curcuma domestica Val.) HASIL PENGERINGAN OVEN KONVEKSI
The water content in fresh turmeric is quite high so it is easily damaged. For this reason, this research is necessary as an effort to handle post-harvest which will increase the shelf life of turmeric. The purposes of this study were to determine the physical properties of turmeric and to determine the effect of differences in drying temperature and duration of flouring on the physical characteristics of turmeric powder. The procedure was started with cleaning and size reduction, drying at temperatures of 60, 70, and 80°C, flouring for 1, 3, and 5 minutes, sifting with no. mesh 60, and measurement of physical properties. Results showed that the lowest water content of turmeric flour dried on 80°C and the 1-minute flouring time was 8.11%. Based on the color analysis test, the drying temperature of 60°C and the time of flouring is 5 minutes with an L (lightness) value of 64.53, a value of 12.47, and b of 51.46. The highest bulk density value was 0,42 g/cm³, obtained from the treatment with a temperature of 60°C and a flouring duration of 3 minutes. The smallest angle of repose value was obtained from a drying temperature of 80°C with a flouring time of 1 minute, namely 42.96°. The highest oil absorption value was obtained from the 80°C temperature treatment and 1-minute flouring time, which was 1.74 mL/g. The most significant water absorption was obtained from the 80°C temperature treatment with 3 minutes of flouring, which was 4.82 mL/g. Based on the analysis of the ANOVA test in this study, the physical characteristics of turmeric powder that affected by drying temperature were only water content and in the correlation test it was found that the observed variables that correlated with temperature were moisture content, bulk density, angle of repose, oil absorption.
Keywords: drying, physical characteristics, turmeric powde
Aktivitas Antikanker Nanokapsul Ekstrak Mengkudu (Morinda citrifolia L.) dengan Pengujian in Vivo pada Fibrosarkoma Mencit Jantan Balb/c
Noni (Morinda citrifolia L.) is one of the many herbs which known as an anticancer agent. Nanoencapsulated form of noni extracts could help the body absorption and able to inhibit the proliferation of cancer cells in vitro. This study was conducted to examine the anticancer activity of nanoencapsulated noni extracts in vivo as the anti-proliferation agent of cancer cells. Noni extract was obtained by maceration method using water as a solvent. The nanocapsule of noni extracts was made using the ionic gelation method by magnetic stirrer with the speed of 1500 rpm. In vivo anticancer activity test was conducted in Balb/c male mice by comparing the treatment of nanoencapsulation noni extracts and non-encapsulated extracts. The result showed that the nanoencapsulated noni extracts have a particle size of 27-59 nm. Percent of inhibition of nanocapsule on cancer cells (specifically on fibrosarcoma of Balb/c male mice) were equal to 54.75% (P2), while non-encapsulated is 49.72% (P1). Nanocapsule of noni extracts has anticancer activity better than non-encapsulated form on fibrosarcoma of Balb/c male mice.
Keywords: anticancer, nanoencapsulation, noni extrac
Risk-aware motion planning in partially known environments
Recent trends envisage robots being deployed in areas deemed dangerous to humans, such as buildings with gas and radiation leaks. In such situations, the model of the underlying hazardous process might be unknown to the agent a priori, giving rise to the problem of planning for safe behaviour in partially known environments. We employ Gaussian process regression to create a probabilistic model of the hazardous process from local noisy samples. The result of this regression is then used by a risk metric, such as the Conditional Value-at-Risk, to reason about the safety at a certain state. The outcome is a risk function that can be employed in optimal motion planning problems. We demonstrate the use of the proposed function in two approaches. First is a sampling-based motion planning algorithm with an event-based trigger for online replanning. Second is an adaptation to the incremental Gaussian Process motion planner (iGPMP2), allowing it to quickly react and adapt to the environment. Both algorithms are evaluated in representative simulation scenarios, where they demonstrate the ability of avoiding high-risk areas
Purifying selection determines the short-term time dependency of evolutionary rates in SARS-CoV-2 and pH1N1 influenza
High throughput sequencing enables rapid genome sequencing during infectious disease outbreaks and provides an opportunity to quantify the evolutionary dynamics of pathogens in near real-time. One difficulty of undertaking evolutionary analyses over short timescales is the dependency of the inferred evolutionary parameters on the timespan of observation. Crucially, there is an increasing number of molecular clock analyses using external evolutionary rate priors to infer evolutionary parameters. However, it is not clear which rate prior is appropriate for a given time window of observation due to the time-dependent nature of evolutionary rate estimates. Here, we characterise the molecular evolutionary dynamics of SARS-CoV-2 and 2009 pandemic H1N1 (pH1N1) influenza during the first 12 months of their respective pandemics. We use Bayesian phylogenetic methods to estimate the dates of emergence, evolutionary rates, and growth rates of SARS-CoV-2 and pH1N1 over time and investigate how varying sampling window and dataset sizes affects the accuracy of parameter estimation. We further use a generalised McDonald-Kreitman test to estimate the number of segregating non-neutral sites over time. We find that the inferred evolutionary parameters for both pandemics are time-dependent, and that the inferred rates of SARS-CoV-2 and pH1N1 decline by ∼50% and ∼100%, respectively, over the course of one year. After at least 4 months since the start of sequence sampling, inferred growth rates and emergence dates remain relatively stable and can be inferred reliably using a logistic growth coalescent model. We show that the time-dependency of the mean substitution rate is due to elevated substitution rates at terminal branches which are 2-4 times higher than those of internal branches for both viruses. The elevated rate at terminal branches is strongly correlated with an increasing number of segregating non-neutral sites, demonstrating the role of purifying selection in generating the time-dependency of evolutionary parameters during pandemics
Localized hypermutation drives the evolution of colistin heteroresistance
These data were created by counting bacterial colonies after serially diluting and plating cultures of Pseudomonas aeruginosa that were incubated in culture medium containing colistin
Self-reported neurotoxic symptoms in hip arthroplasty patients with highly elevated blood cobalt: A case-control study
Objectives
This study aimed to investigate the prevalence of self-reported neurotoxicity and cognitive defects in hip replacement patients with markedly raised blood cobalt.
Methods
Case group comprised 53 patients with metal-on-metal (MoM) implants and a history of blood Co ≥20 μg/L for a median of 3 years (interquartile range, 2–5 years). The control group comprised 53 patients with ceramic-on-ceramic prostheses and blood Co <1 μg/L. Median age was 67 years (interquartile range, 60–74 years). The participants completed the Neurotoxic Symptom Checklist-60, Diabetic Neuropathy Score, Douleur Neuropathique-10, and Systemic Symptom Checklist, and underwent the Mini-Mental State Examination.
Results
The MoM and ceramic-on-ceramic groups were compared, the results were as follows: Neurotoxic Symptom Checklist-60 (median): cognitive defects (2.0 versus 1.9; P = 0.002), chest complaints (1.3 versus 1.3; P = 0.042), balance disturbances (1.3 versus 1.0; P < 0.001), sleep disturbances (2.7 versus 2.0; P = 0.004), mood disorders (2.0 versus 1.5; P = 0.001), sensorimotor disorders (1.6 versus 1.2; P < 0.001), physical complaints (2.0 versus 1.4; P = 0.009), fatigue (2.0 versus 1.6; P = 0.001), and total score (108 versus 90; P < 0.001); abnormal Diabetic Neuropathy Score/Douleur Neuropathique-10 (%): 60.3/13.2 versus 24.5/1.9 (P < 0.001/P = 0.028). Systemic Symptom Checklist (in percent): feeling cold (37.7 versus 17; P = 0.01), weight gain (18.9 versus 1.9; P = 0.008), metallic taste (26.4 versus 3.8; P = 0.002), worsening eyesight (37.7 versus 15.1; P = 0.008) and hearing (24.5 versus 7.5; 0.032), ankle swelling (32.1 versus 7.5; P = 0.002), shortness of breath on exertion (9.4 versus 5.7; P = 0.015), and generalized rash (28.3 versus 7.5; P = 0.01); and Mini-Mental State Examination (median): 29 versus 30 (P = 0.017). Patients in the MoM group were aware of their high cobalt levels and displayed a higher tendency to overreport symptoms (P < 0.001), which could have contributed to the higher scores.
Conclusions
Frequency of reporting a number of symptoms was markedly higher in MoM patients, but clinically significant neurotoxicity was not observed (possibly due to the short exposure to elevated cobalt). Patients with repeated blood Co ≥20 μg/L measurements should be questioned about possible systemic health complaints at follow-up
Trade persistence and trader identity - evidence from the demise of the Hanseatic League
How do trade networks persist following disruptions of political networks? We study different types of persistence following the decline of the Hanseatic League using a panel of 21,590 city-level trade flows over 190 years, covering 1,425 cities. We use the Sound Toll data, a dataset collected by the Danish crown until 1857 that registered every ship entering or leaving the Baltic Sea, forming one of the most granular and extensive trade data sets. We measure trade flows by counting the number of ships sailing on a particular route in a given year and estimate gravity equations using PPML and an appropriate set of fixed effects. Bilateral gravity estimation results show that trade among former Hansa cities only shows persistence after its dissolution in 1669 for about 30 years, but this persistence is not robust across different regression specifications. However, when we incorporate the flag under which a ship is sailing and consider trilateral trade (where an observation is a combination of origin, destination, and flag), we find that trade persistently exceeds the gravity benchmark: Hansa cities continued to trade more with each other, but only on ships that were owned in another former Hansa city and thus sailed under a Hansa flag. Similar effects are found for trade among former Hansa cities and their trading posts abroad, yet again only conditional on the ship sailing under a former Hanseatic flag. Trade flows among the same pair of origin and destination cities, but under a different flag, do not show this persistence. Our main result shows that the identity of traders persists longer and more strongly than other forms of trading relationships we can measure. Apart from these new quantitative and qualitative insights on the persistence of trade flows, our paper is also of historic interest, as it provides new and detailed information on the speed of decline of trade amongst members of the Hanseatic League