scholarly journals Winogradsky's salts solution as a diluting medium for plate count of oligotrophic bacteria in soil.

1981 ◽  
Vol 27 (6) ◽  
pp. 517-518 ◽  
Author(s):  
MARGARET DABEK-SZRENIAWSKA ◽  
TSUTOMU HATTORI
2017 ◽  
Vol 4 (2) ◽  
pp. 87-91
Author(s):  
Ekamaida Ekamaida

The soil fertility aspect is characterized by the good biological properties of the soil. One important element of the soil biological properties is the bacterial population present in it. This research was conducted in the laboratory of Microbiology University of Malikussaleh in the May until June 2016. This study aims to determine the number of bacterial populations in soil organic and inorganic so that can be used as an indicator to know the level of soil fertility. Data analysis was done by T-Test that is by comparing the mean of observation parameter to each soil sample. The sampling method used is a composite method, which combines 9 of soil samples taken from 9 sample points on the same plot diagonally both on organic soil and inorganic soil. The results showed the highest bacterial population was found in total organic soil cfu 180500000 and total inorganic soil cfu 62.500.000


2020 ◽  
Author(s):  
Luke Elissiry ◽  
Jingwen Sun ◽  
Ann M. Hirsch ◽  
Chong Liu

Synthetic fertilizer is responsible for the greatly increased crop yields that have enabled worldwide industrialization. However, the production and use of such fertilizers are environmentally unfriendly and unsustainable; synthetic fertilizers are produced via non-renewable resources and fertilizer runoff causes groundwater contamination and eutrophication. A promising alternative to synthetic fertilizer is bacterial inoculation. In this process, a symbiotic relationship is formed between a crop and bacteria species that can fix nitrogen, solubilize phosphorus, and stimulate plant hormone production. The bacteria carrier developed here aims to maintain bacteria viability while in storage, protect bacteria while encapsulated, and provide a sustained and controllable bacterial release. This novel bacterial delivery method utilizes inorganic nanomaterials, silica microbeads, to encapsulate symbiotic bacteria. These microbeads, which were produced with aqueous, non-toxic precursors, are sprayed directly onto crop seeds and solidify on the seeds as a resilient silica matrix. The bacterial release from the carrier was found by submerging coated seeds in solution to simulate degradation in soil environments, measuring the number of bacteria released by the plate count technique, and comparing the carrier to seeds coated only in bacteria. The carrier’s effectiveness to enhance plant growth was determined through greenhouse plant assays with alfalfa (<i>Medicago sativa</i>) plants and the nitrogen-fixing <i>Sinorhizobium meliloti</i> Rm1021 strain. When compared to bacteria-only inoculation, the silica microbead carrier exhibited significantly (P < 0.05) increased holding capacity of viable bacteria and increased plant growth by a similar amount, demonstrating the capability of inorganic nanomaterials for microbial delivery. The carrier presented in this work has potential applications for commercial agriculture and presents an opportunity to further pursue more sustainable agricultural practices.


2020 ◽  
Author(s):  
Luke Elissiry ◽  
Jingwen Sun ◽  
Ann M. Hirsch ◽  
Chong Liu

Synthetic fertilizer is responsible for the greatly increased crop yields that have enabled worldwide industrialization. However, the production and use of such fertilizers are environmentally unfriendly and unsustainable; synthetic fertilizers are produced via non-renewable resources and fertilizer runoff causes groundwater contamination and eutrophication. A promising alternative to synthetic fertilizer is bacterial inoculation. In this process, a symbiotic relationship is formed between a crop and bacteria species that can fix nitrogen, solubilize phosphorus, and stimulate plant hormone production. The bacteria carrier developed here aims to maintain bacteria viability while in storage, protect bacteria while encapsulated, and provide a sustained and controllable bacterial release. This novel bacterial delivery method utilizes inorganic nanomaterials, silica microbeads, to encapsulate symbiotic bacteria. These microbeads, which were produced with aqueous, non-toxic precursors, are sprayed directly onto crop seeds and solidify on the seeds as a resilient silica matrix. The bacterial release from the carrier was found by submerging coated seeds in solution to simulate degradation in soil environments, measuring the number of bacteria released by the plate count technique, and comparing the carrier to seeds coated only in bacteria. The carrier’s effectiveness to enhance plant growth was determined through greenhouse plant assays with alfalfa (<i>Medicago sativa</i>) plants and the nitrogen-fixing <i>Sinorhizobium meliloti</i> Rm1021 strain. When compared to bacteria-only inoculation, the silica microbead carrier exhibited significantly (P < 0.05) increased holding capacity of viable bacteria and increased plant growth by a similar amount, demonstrating the capability of inorganic nanomaterials for microbial delivery. The carrier presented in this work has potential applications for commercial agriculture and presents an opportunity to further pursue more sustainable agricultural practices.


2016 ◽  
Vol 10 (1) ◽  
pp. 13-23 ◽  
Author(s):  
Agustina Arianita Cahyaningtyas ◽  
Wiwik Pudjiastuti ◽  
Ilham Ramdhan

One attempt to reduce the number of pathogenic microbes in milk is through the pasteurization process. This research aims to determine the effect of storage temperature on the organoleptic, acidity (pH) and growth of coliform bacteria in pasteurized milk. Pasteurized milk is stored at the varies of temperature  4°C (observed for 14 days), 10°C-15°C (observed for 14 days) and 25°C-27°C (observed for 22 hours), as well as also conducted an initial analysis pasteurized milk. The parameters were observed among other organoleptic (smell, taste, color, texture), pH and total coliform bacteria. Testing acidity using pH paper, while the growth of coliform bacteria testing done using Total Plate Count method based on ISO 2897 in 2008. The results of this study indicate that storage at 4°C for 14 days, organoleptic pasteurized milk is still good until the day ke- 8, pH progressively decreases, and the growth of coliform bacteria obtained the highest score of 3100x101 CFU / ml. Storage at 10°C-15°C for 14 days, organoleptic pasteurized milk is still good until the 6th day, the pH progressively decreases, and the growth of coliform bacteria obtained the highest score of 5729x101 CFU / ml. Storage at 25°C-27°C for 22 days, organoleptic pasteurized milk is still good until the 9th, pH progressively decreases, and the growth of coliform bacteria obtained the highest score of 4.3 x106 CFU / ml.ABSTRAKSalah satu usaha untuk mengurangi jumlah mikroba patogen pada susu adalah melalui proses pasteurisasi. Penelitian ini bertujuan untuk mengetahui pengaruh suhu penyimpanan terhadap organoleptik, derajat keasaman (pH) dan pertumbuhan bakteri Coliform pada susu pasteurisasi. Susu pasteurisasi disimpan pada suhu yang bervariasi yaitu suhu 4°C (diamati selama 14 hari), suhu 10°C-15°C (diamati selama 14 hari) dan suhu 25°C-27°C (diamati selama 22 jam), serta dilakukan pula analisa awal susu pasteurisasi. Parameter yang diamati antara lain organoleptik (bau, rasa, warna, tekstur), pH dan jumlah bakteri Coliform. Pengujian derajat keasaman menggunakan kertas pH, sedangkan pengujian pertumbuhan bakteri Coliform dilakukan dengan menggunakan metode Total Plate Count berdasarkan SNI 2897 Tahun 2008. Hasil penelitian ini menunjukkan bahwa penyimpanan pada suhu 4°C selama 14 hari, organoleptik susu pasteurisasi masih baik sampai dengan hari ke-8, pH semakin lama semakin menurun, dan pertumbuhan bakteri Coliform didapatkan nilai tertinggi sebesar 3100x101 Cfu/ml. Penyimpanan pada suhu 10°C-15°C selama 14 hari, organoleptik susu pasteurisasi masih baik sampai hari ke-6, pH semakin lama semakin menurun, dan pertumbuhan bakteri Coliform didapatkan nilai tertinggi sebesar 5729x101 Cfu/ml. Penyimpanan pada suhu 25°C-27°C selama 22 hari, organoleptik susu pasteurisasi masih baik sampai jam ke-9, pH semakin lama semakin menurun, dan pertumbuhan bakteri Coliform didapatkan nilai tertinggi sebesar 4,3 x106 Cfu/ml.Kata kunci : bakteri coliform, derajat keasaman, suhu penyimpanan, organoleptik, susu pasteurisasi


2020 ◽  
Vol 6 (1) ◽  
pp. 087
Author(s):  
Rosy Hutami ◽  
M Fakih Kurniawan ◽  
Henna Khoerunnisa

Sumedang tofu is one of favorite foods for Indonesian society. But many sellers or producers are not aware to the food safety of sumedang tofu. The aims of this study were to analyze the microbial, formalin, and lead (Pb) contents in ready-to-eat sumedang tofu which were sold in traffic jams area in Cicurug, Ciawi, and Cisarua. The analysis were carried out by Total Plate Count (TPC) testing for microbial analysis, potassium permanganate reaction (KMnO4) testing for formaldehyde analysis, and atomic absorption spectrophotometry (AAS) method for lead content analysis in the samples. The results obtained for the microbial analysis were sumedang tofu that were sold in the traffic jam areas of Cicurug, Ciawi, and Cisarua contained contaminant above the treshold (1.4 x 105 colonies / gram to 2.2 x 105 colonies / gram of microbes). All of the samples of sumedang tofu were positive containing formaldehyde. Otherwise, there were no lead (Pb) content in all samples regarding to AAS analysis. This study concluded that the ready-to-eat sumedang tofu those were sold in traffic jam area in the Cicurug, Ciawi, and Cisarua were not suitable for consumption because it contained exceed microbial contamination and formalin which are harmful for human health.Keywords : formalin, microbes, sumedang tofu, lead, traffic jam


Author(s):  
J Aquarista Ingratubun ◽  
Frans G Ijong ◽  
Hens Onibala

Food fermentation is one of various food processing techniques that has sufficient benefits of nutrition values, and also contains lactic acid bacteria which potentially inhibit pathogenic bacteria, thus prolong shelf life of  products. Bakasang is a traditional fermented food from North Sulawesi since many years ago. Reported research of bakasang previously had described that lactic acid bacteria was the dominant isolates and therefore current research  aimed to isolate and identify the lactic acid bacteria which associated during fermentation day 1 and day 15, respectively. Raw materials used were 5 kg intestine and liver of skipjack brought from local market Bersehati Manado. The intestine and liver of skipjack were washed and smashed and mixed with 10% salt  and 5% rice  from weight of the samples and then filled into bottle to be fermented for 15 days. Every 3 days (1,3,6,9,12,15), the samples were collected and analyzed for total lactic acid bacteria by using Total Plate Count Method on de Mann Rogosa Sharpe Agar after incubation at 37°C for 24 h. The colonies  grown were transferred to Tryptic Soy Broth and followed by streaking them on Tryptic Soy Agar and the free growing colony on agar medium were isolated into slant agar which were used for biochemical test such as Gram’s staining, motility test, catalase test, oksidase test, H2S test, IMVIC test (Indole, Methyl Red, Voges Proskauer, Citrate) and carbohydrate fermentation. The results showed that Lactobacillus sp., Bacillus sp., Eubacterium sp., and Bifidobacterium sp. All these four bacteria were distributed from day 1 to day 15 of the fermentation process© Fermentasi bahan pangan merupakan salah satu dari sekian banyak teknik pengolahan makanan yang mempunyai banyak manfaat dari kualitas gizi, mengandung bakteri asam laktat sehingga menghambat bakteri patogen sehingga daya simpan lebih panjang. Bakasang merupakan makanan fermentasi tradisional masyarakat Sulawesi Utara yang sudah ada sejak lama. Penelitian yang telah dilakukan terhadap bakasang menghasilkan informasi bahwa terdapat bakteri asam laktat pada bakasang sehingga menjadi tujuan untuk mengisolasi dan identifikasi bakteri asam laktat selama proses fermentasi 1-15 hari. Bahan baku bakasang ialah jeroan (usus dan hati) ikan cakalang Katsuwonis pelamis sebanyak 5 kg yang diambil dari pasar Bersehati Manado. Sampel jeroan dibersihkan kemudian dihancurkan, ditambahkan garam 10% dan nasi 5% kemudian difermentasi selama 15 hari dengan mengambil tiap-tiap sampel setiap 1, 3, 6, 9, 12, dan 15 untuk dihitung jumlah bakteri asam laktat dengan menggunakkan metode Total Plate Count pada media de Mann Rogosa Sharpe Agar dan koloni yang tumbuh di tumbuhkan  kembali pada media Tryptic Soy Broth  dan digores kembali pada media Tryptic Soy Agar, koloni yang tumbuh digores pada media slant agar yang selanjutnya diidentifikasi bakteri asam laktat berdasarkan uji biokimia yaitu uji pewarnaan Gram, uji motility, uji katalase, uji oksidase, uji H2S dan uji IMVIC (Indole, MethylRed, Voges Proskauer, Citrate). Hasil menunjukkan bahwa selama proses fermentasi berlangsung terdapat 4 genera bakteri asam laktat sesuai yaitu Lactobacillus sp., Bacillus sp., Eubacterium sp., dan Bifidobacterium sp., ke 4 genera ini tersebar pada fermentasi hari 1 sampai hari ke 15©


Domiati cheese is the most popular brand of cheese ripened in brine in the Middle East in terms of consumed quantities. This study was performed to investigate the impact of the microbiological quality of the used raw materials, the applied traditional processing techniques and ripening period on the quality and safety of the produced cheese. Three hundred random composite samples were collected from three factories at Fayoum Governorate, Egypt. Collected samples represent twenty-five each of: raw milk, table salt, calf rennet, microbial rennet, water, environmental air, whey, fresh cheese, ripened cheese & swabs from: worker hands; cheese molds and utensils; tanks. All samples were examined microbiologically for Standard Plate Count (SPC), coliforms count, Staphylococcus aureus (S. aureus) count, total yeast & mould count, presence of E. coli, Salmonellae and Listeria monocytogenes (L. monocytogenes). The mean value of SPC, coliforms, S. aureus and total yeast & mould counts ranged from (79×102 CFU/m3 for air to 13×108 CFU/g for fresh cheese), (7×102 MPN/ cm2 for tank swabs to 80×106 MPN/ml for raw milk), (9×102 CFU/g for salt to 69×106 CFU/g for fresh cheese) and (2×102 CFU/cm2 for hand swabs to 60×104 CFU/g for fresh cheese), respectively. Whereas, E. coli, Salmonella and L. monocytogenes failed to be detected in all examined samples. There were significant differences in all determined microbiological parameters (p ≤0.05) between fresh and ripened cheese which may be attributed to different adverse conditions such as water activity, pH, salt content and temperature carried out to improve the quality of the product.


2020 ◽  
Vol 16 (4) ◽  
pp. 592-600
Author(s):  
Sajad A. Wani ◽  
Tariq A. Bhat ◽  
Nawaz A. Ganie ◽  
Pradyuman Kumar

Background: The extrusion cooking is the most widely used process so the development and consumption of extruded snack products having health and nutritious benefits would help increase the health status of the population. Objective: The aim of this study was to investigate the effect of storage days on physical, microbial activity and sensory characteristics of extruded snacks and kinetics of extruded snacks. Methods: Extruded snacks were produced by extrusion cooking at optimized conditions of temperature, moisture and screw speed of 110°C, 12% (db) and 200 rpm. The products were packed in lowdensity polyethylene (LDPE) and laminated pouches (LP) and were stored at an accelerated temperature condition of 40 ± 2°C. The storage stability in terms of quality parameters such as moisture, hardness, bulk density, color, lateral expansion, sensory characteristics and total plate count was investigated. Results: An increase (p≤0.05) in the value of moisture, bulk density, a*, and total plate count was observed during the storage period, whereas hardness, L*, b*, ΔE and sensory characteristics showed significant (p≤0.05) decreased order with storage period. No significant effect on the lateral expansion of the extruded product was observed. A significant decrease in total carbohydrate, fat and protein content was found during the storage period. The average sensory score and microbial analysis suggested that extruded snacks packed in LDPE pouches can only be acceptable up to the 60th day and extruded snacks packed in LP can be acceptable to more than 90th day. The kinetics of color and hardness suggest first order kinetics. Conclusion: Overall investigation suggested that extruded snacks were more stable in the LP as compared to LDPE pouches.


2017 ◽  
Vol 1 (1) ◽  
pp. 19-23
Author(s):  
Nur Ramadhani

AbstrakKonsumsi selada mentah sangat rentan terhadap kontaminasi bakteri patogen, karena rendahnyamutu mikrobiologis sayuran segar yang ada di Indonesia. Penelitian ini bertujuan untukmenggambarkan status jumlah kuman total (Total Plate Count) pada selada di tingkat pedagang.Metode yang digunakan dalam penelitian ini adalah survey dan pemeriksaan laboratorium denganpendekatan cross sectional. Populasi dalam penelitian ini adalah seluruh selada yang dijual di pasarinduk tradisional dan pasar swalayan di Kota Semarang. Sampel selada berjumlah 32. Hasilpenelitian menunjukkan bahwa dari 32 sampel selada diperoleh jumlah kuman total pada seluruhselada yang diperiksa melebihi batas standar cemaran (lebih dari 103 koloni/ml) tertinggi sebesar1,51 x 107 koloni/ml dan terendah sebesar 4,16 x 105 koloni/ml. Dibutuhkan penanganan seladayang baik selama penjualan oleh pedagang dengan lebih memperhatikan sanitasi, higiene dankesehatan pedagang.Kata kunci: selada, jumlah kuman total, pedagang


Sign in / Sign up

Export Citation Format

Share Document