Gunawan Wijonarko
Program Studi Teknologi Pangan Jurusan Teknologi Pertanian Fakultas Pertanian Universitas Jenderal Soedirman, Purwokerto Indonesia

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Enzimatic Kinetics of Cellulose Hydrolysis using Cellulase from Goat Rumen Fluids Gunawan Wijonarko; Ike Sitoresmi Mulyo Purbowati; Ali Maksum
Indonesian Journal of Food Technology Vol 1 No 1 (2022): Indonesian Journal of Food Technology
Publisher : Program Studi Teknologi Pangan Fakultas Pertanian UNSOED

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (492.575 KB) | DOI: 10.20884/1.ijft.2022.1.1.6121

Abstract

In line with the depletion of petroleum reserves from fossils, humans have forced people to look for alternative renewable energy sources. Nipah plant stems are organic material that contains a lot of lignocellulose. Cellulose in lignocellulose can be hydrolyzed to glucose to produce bioethanol. Problems arise because hydrolysis using pure cellulase requires relatively high costs, so it is necessary to find an alternative source of cheap cellulase. One of the cheap sources of cellulase is goat rumen fluid. Until now, there is not much information regarding the reaction kinetics and cellulase characteristics of goat rumen fluid. The purpose of this study was to isolate crude cellulase extract, determine the KM and Vmax values ​​and determine the optimum temperature and pH. The research was carried out at the Unsoed Agricultural Technology Laboratory. The samples used were seven rumen fluids. The study began with isolation followed by enzymatic kinetics studies. Fractionation was carried out by adding ammonium sulfate salt (50, 60,70, and 80 %), and centrifugation at 7,000 rpm at 4 oC for 15 minutes. Crude cellulase extract with the highest enzyme activity value was used for the study of enzymatic reaction kinetics and characterization. The crude cellulase resistance test to temperature was carried out at 45, 55 and 65 oC and the pH was carried out at pH 4, 5, 6, 7 and 8. The KM and Vmax values ​were determined by measuring the activity of crude cellulase extract at various concentrations of CMC (1, 1 ,5, 2, 2.5, and 3 %). The results showed that crude cellulase extract had an average specific activity of 1.7356 IU/mg. The highest enzyme activity was 0.9854 IU/ml. The optimum crude cellulase extract was at pH 6 with an activity of 1.1015 IU/ml and a temperature of 60 oC with an activity of 0.7829 IU/ml. At a CMC concentration of 2.5% crude cellulase extract had an activity of 0.3179 IU/ml with a Vmax value of 0.0045 IU/ml and a KM of 0.0252 %.
The Influence of Agroclimate, Gandatapa Village, Sumbang Subdistrict on Microbial Profile, Brix Values, and Total Sugar, Naturally Spread Coconut Sap Gunawan Wijonarko; Ike Sitoresmi Mulyo Purbowati; Tatang Widjojoko; Ali Maksum
Indonesian Journal of Food Technology Vol 1 No 2 (2022): Indonesian Journal of Food Technology
Publisher : Program Studi Teknologi Pangan Fakultas Pertanian UNSOED

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (260.308 KB) | DOI: 10.20884/1.ijft.2022.1.2.7226

Abstract

Temperature and relative humidity are factors that affect the microbial profile and brix value of coconut sap. High temperature and relative humidity tend to support microbial growth. On the other hand, high relative humidity will reduce the brix value and total coconut sap sugar. Therefore, it is necessary to study the relationship between agro-climatic conditions with microbial profile, brix value and total sugar in organically run coconut sap in Gandatapa Village. This research is expected to provide benefits for those who need coconut sap as a source of S. cerevisiae and as a raw material for the manufacture of brown sugar. Coconut sap samples were taken using a simple random technique. Temperature and relative humidity were recorded for each sampling. 250 ml of coconut sap was put into a sterile plastic bottle and then using an ice box, it was taken to the Agricultural Technology Laboratory for analysis. The analysis carried out included total microbes, total yeast, total bacteria, yeast percentage, brix value and total coconut sap sugar. The data were analyzed using Pearson correlation to determine the relationship and the degree of closeness. The results showed that temperature and relative humidity were positively correlated with the microbial profile of organically dissolved coconut sap. At an air temperature of 28.4oC and an air humidity of 81%, the total microbes of organically run coconut sap were 6.45 logs, the total yeast was 4.28 log cfu/ml, the total bacteria were 2.52 log cfu/ml and the yeast percentage was 72, 75%. Brix values ​​and total sugar under the same conditions were 16.7% and 8.25%. The value of brix and total sugar of coconut sap is negatively correlated with temperature and relative humidity. There is a strong relationship between temperature and total microbial, brix value and total sugar. The correlation coefficient is 0.71, respectively; -0.81 and -0.78. Strong correlations were also observed between relative humidity and total microbial, total yeast and brix values. The correlation coefficient is 0.85, respectively; 0.82; and -0.83.
Potential Analysis of Brown Sugar Industry Liquid Waste as Raw Material on Making Nata de Coco Gunawan Wijonarko; Ike Sitoresmi Mulyo Purbowati; Ali Maksum
Indonesian Journal of Food Technology Vol 2 No 1 (2023): Indonesian Journal of Food Technology
Publisher : Program Studi Teknologi Pangan Fakultas Pertanian UNSOED

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20884/1.ijft.2023.2.1.9105

Abstract

Brown sugar industry liquid waste is a type of waste that has potential as a medium for making nata. This is because coconut sugar industry liquid waste still contains a lot of sugar as a source of nutrition for the growth of Acetobacter xylinum. In this study, a comparative analysis will be carried out to determine the feasibility of brown sugar industry liquid waste as a medium for making nata. The research was conducted for 2 months at UKM Ngudi Lestari Jaya, Kalisalak Village. Samples were taken randomly using sterile plastic bottles. Sample analysis includes viscosity, color, aroma, degree of brix and pH. Observations on viscosity, color and aroma were carried out before and after boiling. Variable measurements were carried out 3 times. The sensory properties of the samples were analyzed by descriptive qualitative. Brix degree and pH value were analyzed using SPSS version 2.1 with the independent t test method at an alpha value of 5%. The sensory and chemical properties of brown sugar industry liquid waste were compared with coconut water as a standard. The results showed that the liquid waste from the brown sugar industry had a dilute to slightly thick viscosity, light brown to brown color and normal aroma. The results of a comparative analysis showed that there was no difference in sensory properties between the liquid waste and coconut water before and after boiling. The brix degree and the pH value of brown sugar industry liquid waste were respectively 4.3% and 6.3. Meanwhile, the degree of brix and the pH value of coconut water were 5.1% and 5.6, respectively. Based on this, it can be concluded that the liquid waste of brown sugar industry has very good potential as a medium for making nata.