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This study aims to explore the potential of cassava extract (Manihot esculenta)-based growth media for isolating microorganisms from soil. The use of alternative culture media is crucial, especially in regions with limited access to commercial media such as Nutrient Agar or Potato Dextrose Agar, which are relatively expensive. Cassava, a tropical tuber rich in starch and widely available in Indonesia, offers significant promise as a natural substrate for microbial growth. Microbial isolation was performed using a serial dilution method on soil samples collected from an organic garden. The media was prepared from cassava juice mixed with agar and glucose, sterilized, and poured into petri dishes. After inoculation, microbes were incubated for seven days at room temperature. Colony morphology was observed macroscopically, and Gram staining was used to identify bacterial characteristics. The results revealed that cassava extract media effectively supported the growth of diverse microbial colonies, varying in shape, color, and edge structure. Most isolates were identified as Gram-positive, with rod and coccus forms. The presence of pigmented colonies indicates the potential of certain isolates to produce bioactive compounds. In conclusion, cassava extract-based media is a viable alternative for soil microbiology studies. It is not only cost-effective but also facilitates the exploration of local microbial diversity with potential applications in biotechnology, including bioremediation and enzyme production. This approach encourages the use of indigenous resources in scientific research, promoting sustainability and accessibility in microbiological practices.

Solid waste from the tapioca processing industry, which is based on cassava (Manihot esculenta), is a medium rich in organic matter, particularly starch, that supports the growth of various types of microorganisms, especially fungi and bacteria. This study aims to isolate and observe the morphology of microorganisms from solid waste of cassava from the tapioca industry using Potato Dextrose Agar (PDA) medium in a series of pharmaceutical microbiology practicum. Waste samples were taken from the tapioca processing site, then underwent a serial dilution process and inoculation into PDA medium, which was incubated at 28–30°C for 5 days. The isolation results showed the growth of microorganisms with diverse colony morphologies, which are suspected to originate from the genera Aspergillus, Penicillium, and Rhizopus, based on macroscopic and microscopic characteristics. The presence of these microorganisms indicates the potential utilization of cassava waste as a source of microbial isolates for biotechnological and pharmaceutical applications, such as enzyme production and development of bioactive compounds. This practicum activity also contributes to increasing students' understanding of isolation techniques, microorganism characterization, and their role in biological-based waste management.

Tempoyak is a traditional fermented product derived from the flesh of durian fruit (Durio zibethinus) that has undergone a spontaneous fermentation process. This product is very popular in various regions in Indonesia, especially in Sumatra and Kalimantan, and is usually consumed as a cooking spice or side dish. The fermentation process primarily involves the activity of lactic acid bacteria (LAB), a group of microorganisms capable of converting acidic sugars into lactate. LAB plays an important role in forming the distinctive taste of tempoyak, lowering pH, inhibiting the growth of pathogenic microbes, and potentially providing health benefits for consumers. This study aims to isolate and characterize LAB from tempoyak using a microbiological approach. Tempoyak samples were taken from traditional markets, then isolated using MRS agar measurement media. Characterization was carried out through observation of colony morphology, Gram staining, and biochemical tests such as catalase and fermentation of various types of sugars (glucose, sucrose, and maltose). The isolation results showed that all isolates had the typical LAB characteristics, namely Gram-positive, catalase-negative, and rod- and coccus-shaped. The different sugar fermentation abilities indicate species diversity, with the suspected dominant genera being Lactobacillus, Streptococcus, Enterococcus, and Lactococcus. Furthermore, several isolates demonstrated antibacterial activity against Escherichia coli, indicating the potential use of LAB from tempoyak as a probiotic or natural preservative in the food industry. The decrease in pH from 6.2 to 3.6 during the fermentation process also confirmed the metabolic activity of LAB in acid-producing lactate. These findings open up opportunities for utilizing local LAB from tempoyak as functional agents in the development of safe, healthy, and economically valuable fermented food products. Thus, tempoyak not only has cultural value but also has significant scientific and commercial potential.

Mandai is a traditional fermented food made from the inner skin of the cempedak fruit (Artocarpus champeden) and is widely known in South Kalimantan. Its distinctive sour taste is a result of microbial activity during the natural fermentation process. This study highlights the important role of lactic acid bacteria (LAB) as the dominant agents in Mandai fermentation. The main objective of this research is to isolate and characterize LAB from fermented Mandai samples. The methods used in this study include serial dilution, inoculation on Nutrient Agar (NA) media, incubation at room temperature, colony morphology observation, and Gram staining using crystal violet. The results showed the presence of round colonies with a creamy white color and smooth surfaces, which indicate the characteristics of lactic acid bacteria. Most of the isolates showed Gram-positive properties, supporting their identification as lactic acid bacteria. This research not only enriches our understanding of the microbial ecology in Mandai fermentation but also opens up opportunities for utilizing LAB as a natural preservative or functional probiotic in both traditional and modern food products. The presence of LAB in Mandai fermentation suggests the potential to enhance the quality and health benefits of this traditional food, making it a viable source of probiotics beneficial for digestive health. Additionally, the use of LAB in Mandai processing could increase the appeal of this product in broader markets, both locally and internationally. Overall, this study provides a solid foundation for further development in utilizing microbes in traditional food fermentations. Moreover, it opens opportunities to improve the quality and sustainability of Mandai products while raising awareness about the importance of fermentation in enhancing the nutritional value and health benefits of traditional food products.

Batang Bungo River faces severe pollution from domestic waste and illegal gold mining, which has led to an increase in skin diseases and diarrhea among residents of Tanjung Gedang, exacerbated by poor physical-chemical water quality, including low pH and high levels of Total Suspended Solids (TSS) and Chemical Oxygen Demand (COD), all of which foster the growth of pathogenic microorganisme. This study aimed to identify bacteria and fungi present in Batang Bungo River water, characterizing their colony morphology and microscopic structures to understand the impact of pollution on microbial communities. The methodology involved serial dilution of water samples, followed by inoculation onto Nutrient Agar (NA) media using the pour plate technique, and incubation at 37°C for 24-48 hours. Macroscopic observations of colonies (color, shape, texture) were performed, and representative colonies were stained with crystal violet for microscopic observation at 1000x magnification to identify cellular and hyphal structures. The results indicated the presence of various microorganisms, including Gram-positive bacteria, filamentous fungi, and possibly protozoa, with colonies exhibiting characteristics such as off-white color, rough surfaces, and irregular edges. Microscopic examination after crystal violet staining revealed rod-shaped (bacilli), spherical (cocci) structures, and branched filamentous structures resembling hyphae, consistent with a mixture of bacteria and filamentous fungi. The identification of pathogens like Clostridium, Dermatophilus, and Escherichia coli in previous studies, coupled with the poor water quality, confirms significant microbiological and chemical contamination. Crystal violet proved effective as a stain for microscopic identification of microorganism structures. In conclusion, the water quality of Batang Bungo River is highly concerning and requires serious attention for monitoring and management to safeguard public health and the river ecosystem.  

Fermentation of ikan bekasam is a traditional process that involves the activity of microorganisms to produce a product with distinct taste, aroma, and texture. This process includes various microorganisms, such as bacteria, fungi, and yeasts, that play a crucial role in the transformation of fish properties during fermentation. This study aims to isolate, identify, and characterize the microorganisms involved in the fermentation of ikan bekasam using Gram staining and specific staining techniques. The isolation process was carried out using selective media to grow microorganisms from the bekasam samples, including both the fish and the fermentation liquid. Microorganism identification was performed by observing colony morphology, microscopic characteristics, and biochemical reactions. Gram staining was used to differentiate between Gram-positive and Gram-negative bacteria, while specific staining techniques were employed to detect certain cellular structures that aid in the identification of microorganisms. The characterization of microorganisms included an analysis of their physiological and biochemical properties, such as their ability to produce enzymes or secondary metabolites that play a role in fermentation and the development of the characteristic bekasam flavor. The results of the study showed that ikan bekasam contains a variety of microorganisms, including lactic acid bacteria such as Lactobacillus spp. and Pediococcus spp., which play a primary role in fermentation by providing the characteristic sourness. In addition, yeasts such as Saccharomyces cerevisiae were found in the bekasam samples, contributing to the fermentation process. Fungi, such as Aspergillus spp., were also isolated, although their role in the fermentation of ikan bekasam is more limited. This study provides insights into the diversity of microorganisms involved in the fermentation of ikan bekasam and their potential applications in the food industry. These findings open up opportunities to optimize the fermentation process by utilizing these microorganisms to produce more consistent and high-quality bekasam. Future research could further explore the optimal conditions for improving the quality of this fermented product.

Andaliman fruit (Zanthoxylum acanthopodium) is a typical spice from North Sumatra with a unique, spicy flavor and is widely used in traditional Batak cuisine. Although this fruit is known for its natural antimicrobial compounds, which have the potential to prevent the growth of pathogenic microorganisms, andaliman fruit is still at risk of contamination by various microorganisms during post-harvest handling and unhygienic storage. This study aims to assess the potential presence of microbes in andaliman fruit, as well as review methods for isolating and identifying existing microorganisms. Based on a literature review, several microorganisms frequently found in fruits include bacteria from the genera Bacillus, Pseudomonas, and Escherichia, as well as molds from the genera Aspergillus and Penicillium. In the process of microbial isolation, multilevel dilution techniques and cultivation on spectrum media are common methods used. Meanwhile, microbial identification can be carried out through morphological techniques by observing the shape and color of colonies, biochemical tests to examine the characteristics of microbial metabolism, and molecular techniques such as PCR to detect specific microbial DNA. A microbiological understanding of andaliman fruit is crucial to ensure food safety, especially in traditional culinary processing that uses this fruit as a spice. Therefore, efforts are needed to raise awareness of the importance of proper post-harvest handling and storage to minimize the potential for microbial contamination and ensure the quality and safety of andaliman fruit used in cooking. Furthermore, it is crucial to develop effective processing methods to reduce the risk of microbial contamination in andaliman fruit, such as washing or heating before use in cooking. The use of modern processing technologies, such as natural preservatives or processing techniques that can maintain its quality and safety, is also crucial.

Traditional bamboo shoot fermentation is a hereditary practice still preserved by the people of Panti Village, Pasaman Regency. This process not only serves as a natural preservation method but also makes an important contribution to the formation of distinctive flavors and increases the nutritional value of bamboo shoots. One key aspect of this fermentation process is the activity of microorganisms, particularly lactic acid bacteria, which play a role in the production of metabolites such as lactic acid, which functions as a natural preservative, inhibits the growth of pathogenic microbes, and contributes to the distinctive flavor and aroma of fermentation. The main objective of this study was to isolate and identify the types of lactic acid bacteria found in traditionally fermented bamboo shoots. Fermented bamboo shoot samples were taken from several local production houses in Panti Village. The microbial isolation process was carried out using selective media MRS (de Man, Rogosa, and Sharpe) agar, which is commonly used for the growth of lactic acid bacteria. The obtained isolates were then analyzed through colony morphology observation, Gram staining, and microscopic tests to determine initial characteristics. Further identification was carried out through a series of biochemical tests to determine the genus and species of the bacteria. The results of the study showed the presence of several Gram-positive, rod-shaped bacterial isolates that are strongly suspected to belong to the lactic acid bacteria group, such as Lactobacillus plantarum. This bacterium is known to have probiotic potential and functional benefits in fermented food products. These findings indicate that traditional fermented bamboo shoots can be a potential source of functional bacterial isolates that are beneficial for the food industry, particularly in the development of probiotic products, natural preservatives, and food additives based on local fermentation. This study emphasizes the importance of preserving local wisdom in food fermentation practices as a foundation for sustainable, culturally aware food technology innovation and supporting food security based on local resources.

Tempoyak is a traditional fermented product made from durian and widely consumed in Sumatra. Tempoyak fermentation involves lactic acid bacteria (LAB), which are known to have potential as probiotics and as producers of antioxidant compounds. The tempoyak fermentation process plays an important role in increasing nutritional value and health benefits, primarily due to its ability to produce bioactive compounds such as lactic acid and antioxidants that are beneficial for the human body. This study aims to isolate lactic acid bacteria from local fermented tempoyak from Sumatra and evaluate their potential antioxidant activity. Isolation was carried out using the spread method on MRS agar media, which is specifically designed to support the growth of lactic acid bacteria. Next, the obtained isolates were analyzed based on colony morphology, Gram staining, and catalase test for initial identification of the types of bacteria present in tempoyak. After isolation, selected isolates were tested for antioxidant activity using the DPPH test, which is one method to measure the ability of a compound to neutralize free radicals. Vitamin C was used as a positive control in this test. The results showed that several LAB isolates from tempoyak had varying antioxidant activity, with some isolates showing significant potential. The detected antioxidant activity indicates that LAB isolates from tempoyak have the potential to be applied as probiotics with health benefits and as functional food ingredients that can help prevent cell damage caused by free radicals. This study provides evidence that tempoyak, besides being a traditional food, also has the potential to be further developed in the functional food and probiotic industries. These findings add insight into the potential of traditional fermented products, such as tempoyak, which provide not only culinary benefits but also health benefits.

This study aimed to isolate and culture bacteria from well water samples as a first step in identifying microorganisms found in domestic water environments. Well water was chosen because it is one of the main water sources for communities, especially in rural areas, but is highly susceptible to contamination due to human activities such as household waste, agricultural waste, and poor sanitation systems. The isolation process was carried out using the pour plate and scratch plate methods using Nutrient Agar (NA) and MacConkey Agar (MAC) media, which function to detect various types of bacteria, both pathogenic and non-pathogenic, including gram-positive and gram-negative bacteria. Samples were incubated at 37°C for 24–48 hours to allow colony growth. After the incubation period, the growing colonies were observed morphologically based on the color, shape, and edge of the colonies. Next, the colonies were cultured to obtain pure cultures for further analysis. Preliminary results showed a diversity of colony shapes indicating the presence of several bacterial species, such as Escherichia coli, Pseudomonas sp., and possibly Enterobacter sp., which are indicators of air quality and the level of fecal contamination. This study provides a preliminary overview of the microbiological status of well water and the importance of regular testing of domestic water sources. Early identification through isolation and culture is crucial for mitigating public health risks and providing a basis for any necessary air treatment or sanitation interventions. Therefore, the results of this study are expected to serve as a reference for the community and government in sustainably maintaining the quality and safety of well water. The recommended next step is to conduct antibiotic resistance testing to determine the potential hazards of the identified pathogenic bacteria.

Bekasam is a traditional fermented fish-based food popular in various regions in Indonesia, including Batanghari, Jambi. This product is produced through a spontaneous fermentation process that utilizes the activity of microorganisms, particularly lactic acid bacteria (LAB), which play an important role in the formation of distinctive flavors, food safety, and potential health benefits. One type of fish used is lambak fish (Labiobarbus ocellatus), which is commonly found in local waters. Given the high prevalence of cardiovascular disease associated with cholesterol levels, exploring the probiotic potential of local fermented foods presents a strategic opportunity to support public health. This study aims to isolate and identify LAB from bekasam lambak fish from Mersam, Batanghari, and evaluate its initial potential as a candidate for cholesterol-lowering probiotics. The research method was carried out in the laboratory through a series of dilutions (10⁻¹–10⁻⁶) of bekasam samples, followed by cultivation on Nutrient Agar (NA) media using the pour and streak method. Incubation was carried out at 37°C for 24–48 hours. The growing colonies were then observed morphologically and tested using Gram staining. Observations revealed spherical, milky-white colonies with Gram-positive rod-shaped characteristics, indicating they likely belonged to the Lactobacillus genus. This genus is known to lower cholesterol through bile acid binding and free cholesterol assimilation mechanisms in the digestive tract. These findings reinforce the notion that bekasam lambak fish contains local LAB isolates that have the potential to be developed as a natural probiotic raw material. This potential can be utilized in the development of functional fermented food products or nutraceuticals that not only maintain the traditional value of bekasam but also provide preventative health benefits, particularly in controlling cholesterol levels.

Pekasam is a traditional fermented fish product that involves microbial activity, particularly lactic acid bacteria, during its fermentation process. This study aims to isolate and identify bacterial species involved in the fermentation of gabus fish (Channa striata). Samples were collected at different stages of fermentation and analyzed microbiologically. The isolation procedure utilized selective media such as MRS agar and Nutrient Agar (NA). The resulting colonies were observed based on morphology and further identified through biochemical tests, Gram staining, and oxidase tests. The results indicated the dominance of several bacterial isolates, primarily from the Lactobacillus genus. Identification confirmed that lactic acid bacteria played a crucial role in the fermentation process and contributed to the characteristic flavor of the pekasam. This research contributes to the scientific understanding of traditional fish fermentation and offers potential for utilizing local probiotic strains in traditional food products.

Escherichia coli (E. coli) is an indicator bacteria that is often used to assess the level of microbial contamination in food and plants. This study aims to isolate and identify the presence of E. coli from Coleus amboinicus plants which are known to have antibacterial activity. Fresh leaf samples of C. amboinicus were taken from the home yard environment. Isolation was carried out using the serial dilution method and planting on eosin methylene blue (EMB) placement media. Identification was carried out based on colony morphology, Gram staining, and biochemical tests including IMViC (Indole, Methyl Red, Voges-Proskauer, Citrate). The results showed the presence of metallic green colonies on EMB, which showed the characteristics of E. coli. Biochemical tests showed Indole (+), Methyl Red (+), Voges-Proskauer (-), and Citrate (-), which confirmed the isolate as E. coli. The presence of E. coli in C. amboinicus indicates the possibility of environmental fecal contamination, and is a concern in the processing and consumption of this medicinal plant.

This study aims to isolate and identify microorganisms in the form of bacteria and fungi in tilapia fish waste and to demonstrate the effectiveness of turmeric extract (Curcuma longa Linn.) as an antimicrobial agent. Tilapia fish waste samples were fermented for seven days and then microorganisms were isolated using Nutrient Agar (NA) media for bacteria and Potato Dextrose Agar (PDA) for fungi. Turmeric extract treatment was carried out using the disc diffusion method. The results showed the presence of several species of Gram-positive and Gram-negative bacteria, as well as fungal colonies with dominant characteristics of Aspergillus sp. and Fusarium sp. Turmeric extract with a concentration of 20% showed a significant inhibition zone against the growth of pathogenic bacteria and fungi. The content of secondary metabolites such as alkaloids, tannins, and phenolics in turmeric extract is thought to be the main factor in antimicrobial activity.

Proteolytic bacteria are bacteria that can degrade proteins by producing extracellular protease enzymes. Proteolytic bacteria can be found in mangrove soil. This is because the dry weight of mangrove leaf litter contains 61% protein. The purpose of this study was to determine the presence of proteolytic bacterial isolates from mangrove soil in Pandaratan Beach, Sarudik District, Central Tapanuli Regency and to characterize them. This study used a laboratory experimental method which was analyzed descriptively. Soil sampling was carried out at two location points I (sandy) and location II (muddy) which were isolated using SMA media with the streak plate method. Characterization includes macroscopic and microscopic observations as well as biochemical tests. The results of the study found that there were 15 isolates of proteolytic bacteria isolated from the mangrove soil of Pandaratan Beach, Central Tapanuli. The highest activity test of the proteolytic index (IP) was obtained 0.82 mm by the Micrococcus (L1) and 0.09 mm lowest by Brevibacillus (L2). A total of 11 genera of proteolytic bacteria were found, including Curtobacterium (P1 and L7), Bacillus (P2, P4, and P7), Enterococcus (P3), Brevibacillus (P5 and L2), Carnobacterium (P6), Paenibacillus (P8), Micrococcus (L1), Vagococcus (L3), Marinococcus (L4), Halobacillus (L5), Sporosarcina (L6).

Pemeliharaan circuit breaker dengan media gas SF6 di PT.Indonesia Power suralaya merupakan suatu pemeliharaan yang dilakukan selama 2 tahun sekali dengan meggunakan sistem overhoul. Pengecekan ini meliputi pengukuran  tahanan isolasi, keserempakan pembukaan dan penutupan kontak dan tahanan kontak. Data yang diambil merupakan data pengecekan yang diambil dari data perdua tahunan dan merupakan data yang pasti. Selain pemeliharaan overhoul circuit breaker ini juga dilakukan pengecekan secara rutin selama satu bulan sekali, untuk memastikan bahwasannya tidak ada permasalahan pada alat yang digunakan sebagai sistem proteksi untuk penanganan penyaluran aliran listrik.                                                       

Komponen yang beroperasi selama 24 jam setiap hari memungkinkan terjadinya penurunan kondisi peralatan secara tiba-tiba dan tidak dapat terduga. Seperti halnya pada GIS Labuan 150kV PT. PLN (Persero) ULTG Rangkasbitung terjadi kebocoran pada pipa fleksibel kompartemen GS 200 Fasa S sehingga mengakibatkan terjadinya penurunan tekanan gas SF6 yang sangat signifikan yaitu dari 0,42 Mpa menjadi 0,38 Mpa. Hal tersebut dapat memungkinkan terjadinya short circuit dan gangguan sistem pada peralatan sehingga dapat menyebabkan berkurangnya kehandalan sistem operasi kelistrikan. Penelitian ini bertujuan untuk memahami bagaimana fungsi gas SF6 (Sulfur Hexafluoride) sebagai media isolasi dan pemadam busur api pada GIS (Gas Insulated Switchgear) serta mengetahui bagaimana kualitas gas SF6 pada GIS Labuan 150kV PT. PLN (Persero) ULTG Rangkasbitung. Penelitian ini menggunakan metode penelitian secara langsung dengan melaksanakan observasi lapangan dan wawancara. Hasil dari penelitian yang telah dilakuan berupa pemahaman mengenai sistem operasi GIS (Gas Insulated Switchgear) yang menggunakan Gas SF6 sebagai media isolasi.