Diameter Of Clear Zone Research Articles

Antimicrobial and Preservative Effects of the Combinations of Nisin, Tea Polyphenols, Rosemary Extract, and Chitosan on Pasteurized Chicken Sausage

This study was conducted to evaluate the antimicrobial and preservative effects of the combinations of nisin (NS), tea polyphenols (TP), rosemary extract (RE), and chitosan (CS) on pasteurized chicken sausage. An orthogonal test revealed that the most effective preservative was a mixture of 0.05% NS plus 0.05% TP plus 0.03% RE plus 0.55% CS (weight by sausage weight). This mixture had antimicrobial and antioxidant effects in pasteurized chicken sausage and extended the shelf life to >30 days at 4°C. The inhibitory effects of NS, TP, RE, and CS were also evaluated against Pseudomonas aeruginosa, lactic acid bacteria (LAB), and Staphylococcus aureus, the dominant spoilage and pathogenic bacteria in pasteurized chicken sausage. NS had the greatest inhibitory effect on LAB and S. aureus, with inhibitory zone diameters of 19.7 and 17.8 mm, respectively. TP had the largest inhibitory effect on P. aeruginosa, with a clear zone diameter of 18.2 mm. These results indicate that the combination of NS, TP, RE, and CS could be used as a natural preservative to efficiently inhibit the growth of microorganisms in pasteurized chicken sausage and improve its safety and shelf life.

Distinguish between two Species of streptococcus by sk gene

This study aims at the possibility of using the sk gene encoding the Streptokinase protein to differentiatebetween the different species belonging to the genus Streptococcus which can produce this protein., 12bacterial isolates belonging to the genus Streptococcus were obtained, and by using thecaseinolytic assaytest, all the studied isolates gave a positive result with different clear zone diameters around the wells. DNAwas then extracted from the isolated bacteria and used as a template for the amplification of the sk gene usingspecific primers for the gene. The 1300 bp was amplified as PCR product comparing them with the DNAladder. The target gene was obtained from of S. pyogenes and S. dysgalactiae subsp. equisimilis. . The resultwas confirmed by identifying the gene sequences and comparing it with the database in NCBI, which showeda similarity of more than 98% and the percentage of similarity between the genes of the different specieswas more than 99%. The sk gene for both species were digested with BtgZI and MboII restriction enzymes.The results of the agarose gel electrophoresis showed that the gene belonging to the S. pyogenes possessesrestriction sites for BtgZI restriction enzymes that differ in location from that of the S. dysgalactiae subsp.equisimilis. Where the bundles appeared in different locations, which means that the location and numberof restriction sites differ between the two types, and this feature can be used to differentiate between them.

Ethanolic extract of local sorghum seedcoat (Sorghum bicolor [L.] Moench) as a potential bacterial growth inhibitor

Research on the antibacterial activity of ethanol extract from seedcoat of local Sorghum (Sorghum bicolor [L.] Moench) against Staphylococcus aureus and Escherichia coli has been conducted. The purpose of this study was to determine the minimum inhibitory concentration of extract against both gram-positive and negative bacteria. The extraction method used in this study was a maceration method using ethanol as a solvent. Antibacterial activity test was carried out with several concentrations, namely 1 g/mL, 0.8 g/mL, 0.6 g/mL, 0.4 g/mL, 0.2 g/mL, 0.1 g/mL, 0.05 g/mL, 0.025 g/mL, and 0.01 g/mL. The results showed that the extract inhibited bacterial growth in a wide range of concentrations. The smallest inhibition was at a concentration of 0.05 g/mL with a clear zone diameter of 10.29 mm in Staphylococcus aureus and 11.70 mm in Escherichia coli. Ethanol extract of local Sorghum seedcoat exhibited a strong inhibition ability and probably a potential antibacterial agent source.

Antifungal activities of lactic acid bacteria and yeast isolated from various types of Tempe

Mycotoxin-producing fungi are harmful contaminants in food and feed products. Lactic acid bacteria (LAB) and yeast groups are known to produce antifungals. Indonesia is known as a Tempe-producing country, an important functional fermented food. Soybean Tempe has been commonly known and well-studied, while other types of Tempe such as Tempe Gembus, Tempe Koro, Tempe Lamtoro and Oncom have not been well studied. This study aimed to determine LAB and yeast population in various types of Tempe and to select antifungal activity against mycotoxin-producing fungi. Research methods included total aflatoxin analysis in Tempe products, enumeration and isolation of LAB and yeast, and antifungal assay. The results showed that the total aflatoxins in all Tempe products were 1.99 - 3.84 ppb and it was qualified as food for consumption. The total LABs were 7.16 - 8.25 log10 cfu/g while the total yeast was 4.48 - 7.38 log10 cfu/gram. The highest antifungal activities in mycotoxin-producing fungi such as Aspergillus parasiticus and Penicillium citrinum, shown by LAB G1 isolates which were identified as Lactobacillus sp. and yeast G6K1 and G6K2 which were identified as Saccharomyces spp. All the selected isolates were isolated from Tempe Gembus. The clear zone diameter of antifungals was 15-20 mm and 3.5 mm respectively for LAB G1 and G6K1-G6K2. These selected LAB and yeast had the potential to be used as natural bio-preservatives in functional food products to prevent the growth of mycotoxin-producing fungi.

Production of cellulase enzyme by Aspergillus niger, Aspergillus terreus and Penicillium sp. isolated from soil

This research was aimed to isolate cellulolytic fungi showing hyper-cellulase activity. Potential cellulase-producing fungi were isolated from different soil samples, particularly near agro-wastes dumping sites. Among the various isolates obtained from different sampling sites, three different fungi were selected depending upon the clear zone diameter produced in Carboxymethyl Cellulose (CMC) agar. CMC hydrolysis by all three fungal strains exhibited their activities at pH 5.5-7.5, whereas maximum activity occurred at pH 5.5. Enzymes were also pH stable. Based on K m and V max values, the endoglucanase and β-glucosidase enzymes of Aspergillus niger were most efficient. The characterization of these fungi may also provide an opportunity to screen the cellulase enzymes for their further utilization in bio-ethanol production using lignocellulosic agro-wastes.

Nitrogen Optimization on Rhamnolipid Biosurfactant Production from Pseudoxanthomonas sp. G3 and Its Preservation Techniques

Biosurfactant is a microbial bioproduct that is used to reduce the surface tension, and can acted as emulsifier, dispersant, and anti-adhesive. Optimization of biosurfactant production needs to be done, not only to increase its production quantity, but also to reduce overall production cost. This study aims to determine the most suitable and optimum concentration of nitrogen source for biosurfactant production and its preservation techniques. The biosurfactant was produced by Pseudoxanthomonas sp. G3 using minimal salt medium with 2% light crude oil as carbon source and different nitrogen sources in the form of urea, sodium nitrate, and ammonium nitrate. The activity of biosurfactants were measured by emulsification index (E24), interfacial tense (IFT), oil drop assay, and dry weight. Potassium sorbate 0.2% (w/v) was used as preservative agent. The results showed that biosurfactant production using sodium nitrate as a nitrogen source provides the highest activity and yield. The E24 value was 76.63% and the clear zone diameter observed was 0.875 cm. The overall decreased in IFT was 35.4% and the biosurfactant dry weight was 0.45 gL-1. Microbial contamination occurred after 3 weeks of storage in the treatment without the addition of preservative. It also showed that the activity of biosurfactants (emulsification and IFT) were gradually decreased during storage. In conclusion, the optimum biosurfactant production by Pseudoxanthomonas sp. G3 was obtained by the addition of sodium nitrate 0.3% (w/v). Meanwhile, the most effective biosurfactant preservation method was by adding potassium sorbate which was stored at 4 ℃.

Synergistic bactericidal effect of clove oil and encapsulated atmospheric pressure plasma against Escherichia coli O157:H7 and Staphylococcus aureus and its mechanism of action

We investigated the bactericidal effect of clove oil and encapsulated atmospheric pressure plasma (EAP), individually or in combination, against Escherichia coli O157:H7 and Staphylococcus aureus. The bactericidal effect of the combined treatment was also investigated in inoculated beef jerky. For both pathogens, clove oil and EAP single treatments resulted in less than 3.0-log reductions, whereas the combined treatment resulted in more than 7.5-log reductions. The disc-diffusion assay and gas chromatography-mass spectrometry showed no changes in both the clear zone diameter and chemical composition of clove oil before and after the EAP treatment. Significant changes in cell membrane permeability and cell morphology resulting from the combined treatment of clove oil and EAP were evidenced by increased in UV absorption of cell supernatants, increased cell staining with propidium iodide, and changes in cell structure revealed by transmission electron microscopy. The synergistic bactericidal effects of clove oil and EAP against both pathogens were also observed in inoculated beef jerky, but the treatments were less effective against S. aureus, presumably due to thicker peptidoglycan layer. Experiments also demonstrated that the synergistic bactericidal effects between clove oil and EAP are due to clove oil increasing the susceptibility of the bacteria to subsequent EAP treatment, and does not involve alteration of the antibacterial activity of clove oil by EAP.

Antibacterial activity of curcuminoid derivatives resulted from hydrogenation reaction with Pd-C catalyst from turmeric (Curcuma longa) rhizomes extract

Turmeric (Curcuma longa) is one of the most commonly used plants for traditional medicine especially for antibacterial activity. However, because of its color, it is necessary to conduct a transformation reaction that can change the color of curcuminoid into colorless but still have antibacterial activity. The aim of this research was to analyze the antibacterial activity of tetrahydrocurcuminoid, derived from hydrogenation of curcuminoid isolated from turmeric extract towards Staphylococcus aureus and Fusobacterium nucleatum. Hydrogenation reaction was carried out using H2 gas with Pd-C catalyst to remove the conjugated double bond in curcuminoid to form tetrahydrocurcuminoid. Tetrahydrocurcuminoid then was purified by using silica gel column chromatography and characterized using UV-Vis and FTIR spectral data. Antibacterial activity of curcuminoid and tetrahydrocurcuminoid were tested against S. aureus and F. nucleatum using disc diffusion method. The antibacterial activity showed that tetrahydrocurcuminoid had a better antibacterial activity against S. aureus and F. nucleatum with average diameter of clear zone were 5.5 and 2.75 mm, respectively, than curcuminoid with 2 and 2.5 mm, respectively.

Antibacterial Activity Test of Wet and Dried Extracts of Calabash Tree (Crescentia cujete L.) against Aeromonas hydrophilla

Study to determine the antibacterial activity of wet and dry extract of the leaf, fruit, and bark of Calabash tree (Crescentia cujete L.) against the growth of Aeromonas hydrophila. The solvent extraction process was done by using 96% ethanol in the maceration method. Antibacterial test results using diffusion agar to decide clear zone and tube series of dilution test to provide MIC and MBC. Fresh leaf extract produces the highest clear zone diameter (20.06 mm), after which fresh bark extract (12.81 mm), and the last is fresh fruit extract (3.22 mm). In contrast to fresh extracts, the dried extracts are have not clear zone. MIC (Minimum Inhibitory Concentration) of Calabash Tree fresh leaf extract against Aeromonas hydrophila is 80%, and MBC (Minimum Bactericidal Concentration) is 100%.

<i>In Vitro</i> Assessment of Antioxidant, Thrombolytic, Antimicrobial Activities of Medicinal Plant <i>Pandanus odoratissimus L.</i> Leaves Extract

The present study was carried out to investigate phytochemical, antioxidant; antimicrobial, thrombolytic activity and estimate total phenolic, total flavonoid content of Pandanus odoratissimus (p.odoratissimus) leaves of methanol extract. In thrombolytic activity, aqueous soluble fraction (AQSF) exhibited highest percentage (46.58 %) of potential to lyse blood clot compared to standard drug streptokinase (69.52 %). In antimicrobial assay, dichloromethane soluble fraction (DCMSF) explored the highest diameter of clear zone of inhibition against both gram positive (19.60 ± 0.12 mm) and gram negative (20.00 ± 0.20 mm) bacteria compared to standard antibiotic, Kanamycin (50.00 ± 0.19). Levels of antioxidant were determined by DPPH assay followed by calculated IC50 values of different Kupchan extracts. The methyl soluble fraction (MSF) showed the lowest level of IC50 value (36.70 ± 0.32 µg/mL) in comparison to ascorbic acid (12.48 ± 0.09 µg/mL) while MSF disclosed the maximum level (62.19 ± 0.26 mg of GAE/g of extract) of total phenolic content in the extracts of P. odoratissimus. This study was conducted to validate the P. odoratissimus leaves used as a folk medicine such as, antioxidant, thrombolytic, and antimicrobial potential.

Identification of listeriosis and potency of antimicrobial probiotics by in vitro test on beef cattle

The study aimed to identify listeriosis in cattle by using conventional and molecular diagnostic methods and to test the implementation of probiotics as inhibitors of listeriosis in cattle in vitro. Laboratory tests conducted to diagnose listeriosis and antimicrobial activity. Parameters included the color, shape, size, and surface of the colony, shape, and gram staining. Molecularly, the observed variable: the size of the molecular weight of PCR products. Results showed that the conventional method diagnoses of Listeria monocytogenes isolate having the green colonies, round shapes, 1 mm size, shiny convex surfaces, gram-positive, 1-2 μm × 0.5 μm short stem and Listeria innocua isolate had white colonies, round shape, slippery surface, 1-2 mm size, gram-positive, short stem size 0.3 - 0.5 μm. Additionally, conventional method diagnosis found 12 listeriosis isolates [37.5%]. Molecular diagnosis using specific PCR to Listeria monocytogenes and Listeria innocua, produce a product with 1500 bp in size and found in 8 listeriosis isolates [25%]. The highest inhibition zone was obtained from Weissella paramesentroides LAB strain 259 with 22 mm clear zone diameter in the Listeria monocytogenes test bacteria and LAB Pediacoccus pentosaceus CTSPLI strain with a 24 mm clear zone diameter in the Listeria innocua test bacteria. In conclusion, probiotics can inhibit the growth of Listeria monocytogenes and Listeria innocua from uterine isolates.

Isolation and screening of extracellular enzymatic activity of endophytic fungi isolated from Thai orchids

Endophytes living inside plant tissues are known to be a rich source of unique bioactive compounds. In the current study, endophytic fungi were isolated from the leaves, stems and roots of five species of epiphytic orchids: Doritis pulcherrima, Dendrobiuma phyllum, Dendrobium anosmum, Ascocentrum curvifolium and Aerides falcata. In total, 52 endophytic isolates were obtained from the orchid samples, with the most (27) being obtained from leaf segments followed by roots and stems. All of the endophytic isolates were assessed for their potential role in producing extracellular enzymes, including amylase, protease, cellulase, pectinase and lipase on solid media. The results showed that 67%, 56%, 49%, 39% and 25% of the endophytic isolates had the ability to produce lipase, cellulase, pectinase, protease and amylase enzymes, respectively. One endophytic isolate, DapR 02, isolated from the root of Dendrobium aphyllum produced significantly more pectinase enzyme secretion with a ratio of the clear zone diameter to the colony diameter of 23. It was identified as Pseudopestalotiopsis theae using morphological characteristics and molecular analysis. This was the first report of the pectinase enzyme production potential of the endophyte Pseudopestalotiopsis theae. Therefore, an experiment was conducted to optimize the pectinase production in the DapR 02 isolate. High pectinase production of 1.524 U/mL was observed under culture conditions of 30 °C and pH 3.

Isolation of Cellulolytic Bacteria from Mangrove Sediment in Dumai Marine Station Riau and the Antibacterial Activity against Pathogens

Cellulolytic bacteria are a group of bacteria that have an ability to degrade material containing cellulose and have potency to inhibit the growth of pathogenic bacteria. The bacteria can be found in soil or sediment in the mangrove ecosystem. This research aimed to: 1) isolate cellulolylitic bacteria from mangrove sediments in Dumai Marine Station, of Riau, Indonesia, 2) to examine the antagonism against pathogenic bacteria (Escherichia coli, Pesudomonas aeruginosa, Vibrio alginolyticus), and 3) to identify and the phenotype and genetic characters of the potential isolates. The bacteria were isolated on Zobell Marine Agar 2216 added with carboxymethyl cellulose (CMC). Cellulolytic index value was obtained by reducing clear zone diameter with the bacterial colony diameter. Disc diffusion agar method was used to examine antagonism of selected isolates against pathogens. The isolates were observed for the colony and cell morphology, biochemical and genetically characters. Twenty four isolates showed cellulolytic activity and index values ranged from 1.00 to 2.86 and 0.01 to 2.12, respectively. Nine of selected isolates performed ranges of zone inhibition against E. coli, P. aeruginosa and V. alginolyticus from 2.38 ± 0.21 mm to 3.58 ± 0.83 mm, 2.75 ± 0. 59 mm - 4.81 ± 0.57 mm and 2.28 ± 0.45 mm - 4.68 ± 1.40 mm, respectively. Based on the 16S rDNA sequence analysis, three cellulolytic isolates indicated similarity to Bacillus toyonensis (99.53 %).

Formulation of anti-acne concealer containing cinnamon oil with antimicrobial activity against Propionibacterium acnes.

This study aimed to develop an anti-acne concealer containing essential oil with anti-Propionibacterium acnes activity. Antimicrobial activity of cinnamon oil, galangal oil, and eucalyptus oil against P. acnes DMST 14916 was assayed using agar disc diffusion and the broth dilution method. Cinnamon oil showed the maximum inhibitory activity against P. acnes with a clear zone diameter of 36.75 ± 1.06 mm, compared to 14.67 ± 0.58 and 41.83 ± 1.04 mm for tea tree oil and clindamycin, respectively. The minimum inhibitory concentration value of cinnamon oil was 5 mg/mL. Among five formulations of concealer incorporating 0.5% w/w cinnamon oil, F4 provided good texture, coverage, and spreadability with anti-P. acnes activity and stable under determined storage conditions. Cinnamon oil could be a promising cosmetic ingredient for anti-acne products, and F4 concealer may be useful for both covering skin imperfections and the management of acne.

Distribusi Bakteri Penghasil Enzim Ekstraseluler Pada Saluran Pencernaan Lobster Mutiara (Panulirus ornatus)

The activity of the digestive function of animals is influenced by the secretion of extracellular enzymes from bacteria in the digestive tract. This study aims to evaluate the distribution of bacteria producing protease enzyme, amylase and lipase from the digestive tract of pearl lobster, Panulirus ornatus. Bacterial isolates that have extracellular enzyme activity are based on their ability to form clear zones in the test media. The results showed that of 51 bacterial isolates from the digestive tract of P. ornatus, proteolytic bacteria were 27.45%, amylolytic bacteria were 23.53% and lipolytic bacteria were 21.77%. Based on bacterial dominance in the gastrointestinal segment, namely the cardiac, piloric and intestinal sections, it was dominated by amylolytic bacteria at 33.33%, proteolytic at 37.50% and lipolytic at 29.41%. The activity of proteolytic, amylolytic and lipolytic bacteria based on the highest clear zone diameter was achieved respectively by SP5 isolates of 12 mm, SK10 isolates of 21 mm and SU15 isolates of 20 mm. The three bacterial isolates were potential as probiotic aquacultur candidates

Uji Efektivitas Antibiotik Ekstrak Daun Belimbing Wuluh (Averrhoa Billimbi L) Terhadap Pertumbuhan Staphyloccus aureus Secara In Vitro

Infection is the most common disease in Indonesia. Infection diseases are caused by microorganisms such as the Staphylococcus aureus. While in fact, many plants can be used as traditional medicine, one of those is the leaves of belimbing wuluh tree (Averrhoa bilimbi L.) This study aims to determine the inhibitory power of leaves of Cucumber tree (Averrhoa bilimbi L.) on growth of Staphylococcus aureus in vitro. This study used an experimental method. The technique used to measure antibiotic activity is the method of disk diffusion and continued by Kruskal- Wallis test and Mann-Whitney test. Leaves of belimbing wuluh tree (Averrhoa bilimbi L.) at concentrations of 40%, 60%, 80%, 100%, amoksisilin, and aquabidest resulted in average diameter of clear zone. leaves of belimbing wuluh tree (Averrhoa bilimbi L.) have an inhibitory power against Staphylococcus aureus. Keywords: Leaves of belimbing wuluh tree (Averrhoa bilimbi L.), Staphylococcus aureus.

Effectiveness of Durian Peel Extract as A Natural Anti-Bacterial Agent

Durian (durio zibertinus) is a native tropical fruit from Southeast Asia, especially Indonesia. Durian peel is the highest composition of durian fruit (60-75%), and is still considered as waste that causes environmental problems. This study aimed to analyze the content of secondary metabolites extract, to analyze the anti-bacterial activity of durian peel extract against gram-negative and gram-positive bacteria, and to calculate the effectiveness of durian skin durian peel extract as a natural anti-bacterial ingredient in hand sanitizer products by using the paper disc method. Durian peel was extracted with ethanol to obtain extract solution which was then separated from the solvent and applied as an ingredient for hand sanitizer. The Analysis results showed that durian peel extract contains triterpenoids, alkaloids, and saponins, which are phytochemical compounds that anti-bacterial function. Durian peel extract at concentration of 1% wt. inhibited the growth of Escherichia coli, Salmonella thyposa and Sthapylococcus aureus with a clear zone diameters of 7.4 mm, 8.2 mm and 8.6 mm, respectively. In anti-septic tests, hand sanitizer samples containing durian peel extract showed that the interaction between the concentration of durian peel extract and the sampling duration simultaneously gave a significant effect in reducing the number of microorganism colonies.

Isolation and identification of the same type LMG1242 of biosurfactant-producing strain of Pseudomonas aeruginosa from different oil contaminated soils

Emulsification is a major rate limiting step in any biological conversion of heavy hydrocarbons. Here, thirty bacterial strains were isolated from seven native consortia and screened for biosurfactant-producing activities which could enhance emulsification of heavy oils. The consortia were obtained by sampling from oil contaminated soils of different petroleum refineries of Iran. The oil spreading test, drop collapse test, emulsification index (E24) and surface tension measurements were used to evaluate the biosurfactant producing activities of the strains. A total number of 5 strains out of 30 were finally selected as the best biosurfactant-producing bacteria. The clear zone diameters in their oil spreading test were 4 to 5 cm, and E24 were 48 to 92%. The selected strains also properly lowered the surface tensions of the supernatants to 23.5-32 mN/m when grown on heavy diesel. All the selected strains were identified by 16S rRNA sequencing analysis as Pseudomonas aeruginosa LMG1242 (99.9% homology) which is a newly isolated type in oil polluted soils. The results suggest P. aeruginosa LMG1242 as a predominant and highly active biosurfactant producing bacterium which could be further evaluated in petroleum bioremediation and bioprocessing applications.

DAYA HAMBAT EKSTRAK BUAH ANDALIMAN (Zanthoxylum acanthopodium DC) DALAM ETIL ASETAT TERHADAP PERTUMBUHAN Escherichia coli

This study aims to determine the Minimum Inhibitory Consentration (MIC) of andaliman fruit extract (Zanthoxylum acanthopodium DC) in ethyl acetate against the growth of Escherichia coli bacteria. The design of this study used an experimental method with 10 extract concentrations for MIC testing, namely 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and 100% with 2 repetitions so that they were obtained 20 experimental units. The variables observed were the formation of clear zones, namely the inhibition produced by the presence of antimicrobial activity from andaliman fruit extract in ethyl acetate against the growth of Escherichia coli. Data from research results are presented in the form of tables, figure and discussed descriptively. Andaliman fruit extracts in ethyl acetate have varying inhibitory forces, namely at the concentrations of concentrations of 10% to 20% was 0.65 mm to 3.15 mm with weak inhibition categories, concentrations of 30% to 50% was 5.25 mm to 6, 60 mm in the moderate inhibition category and concentrations of 60% to 100% showed strong inhibition categories with inhibition diameters of 7.20 mm to 9.60 mm. Minimum Inhibitory Concentration (MIC) for the growth of Escherichia coli was at the concentration of 60% with a clear zone diameter of 7.2 mm with a strong category.
 
 
 Keywords : Andaliman fruit, Escherichia coli, antibacterial.

Short Communication: Isolation and characterization of thermophilic actinobacteria as proteolytic enzyme producer from Ie Seuum Hot Spring, Aceh Besar, Indonesia

Abstract. Fitri L, Putri KA, Suhartono, Ismail YS. 2019. Short Communication: Isolation and characterization of thermophilic actinobacteria as proteolytic enzyme producer from Ie Seuum Hot Spring, Aceh Besar, Indonesia. Biodiversitas 20: 2802-2808. Proteases are enzymes who catalyze the breakdown of peptide bonds in proteins. This enzyme could be produced from thermophilic bacteria that are able to grow at temperatures of 45-80ºC and are stable to heat. The samples were collected at Ie Seu'um hot spring, Aceh Besar. This study aimed to isolate, to characterize and to determine actinobacteria that were capable of producing protease enzymes. The sampling method in this study was conducted by purposive sampling at temperatures of 50, 60 and 70ºC. Isolation of thermophilic actinobacteria was carried out in Humic Acid Vitamin B (HV) Agar medium and morphological characterization was carried out in Yeast Malt Agar (YMA), Yeast Starch Agar (YSA), Oatmeal Agar (OA) media. Microscopic characterization and measurement of clear zone diameter formed were carried out in skim milk medium. The results showed that one actinobacteria isolate was obtained at a temperature of 50ºC and five isolates at a temperature of 60ºC, meanwhile, no actinobacteria could be obtained at a temperature of 70ºC. A total of 4 isolates obtained were able to produce protease enzymes. The highest Proteolytic Index (IP) value was obtained from IS01 which was 3.8.