The effect of H-Ion concentration upon aerobic polysaccharide synthesis by resting cells of Saccharomyces cerevisiae

1969 ◽  
Vol 64 (4) ◽  
pp. 315-318 ◽  
Author(s):  
C. J. Barwell ◽  
R. V. Brunt
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Ion Concentration ◽  
Resting Cells ◽  
Polysaccharide Synthesis

Net synthesis of sterols in resting cells of Saccharomyces cerevisiae

1954 ◽  
Vol 13 ◽  
pp. 591 ◽  
Author(s):  
Harold P. Klein ◽  
Norman R. Eaton ◽  
John C. Murphy
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Resting Cells

scholarly journals Biosorpsi logam Zn oleh biomassa Saccharomyces cerevisiae *) Biosorption of Zn metal by Saccharomyces cerevisiae biomass

2016 ◽  
Vol 75 (2) ◽  
Author(s):  
Irma KRESNAWATY ◽  
. TRI-PANJI
Keyword(s):  
Waste Water ◽  
Saccharomyces Cerevisiae ◽  
Heavy Metal ◽  
Industrial Waste ◽  
Contact Time ◽  
Sorption Process ◽  
Ion Concentration ◽  
Excess Base ◽  
Maximum Limit ◽  
Latex Rubber

SummaryHeavy metal in waste water potentiallycauses environmental pollution. Generally,heavy metal pollutions come from metalplating, textile, latex-rubber goods, and otherindustries. The process of latex-rubber goodindustries uses heavy metal in the form ofZnO as accelerator for rubber vulcanizationprocess, so that Zn 2+ ion exists in wastewatereffluents in concentration as much as 300 ppm,whereas the maximum limit allowed is 2.5 ppm.The chemical way generally used to decreaseZn 2+ concentration in wastewater effluents isby adding bases, NaOH or Ca(OH) 2 until pHreached 11, hence this metal is precipitated asits hydroxide. However, the way is done, isvery high cost and has a risk of the emergencesecondary pollution caused by excess base. Analternative way to absorb Zn 2+ consideredinexpensive is by using biosorbent in the formof Saccharomyces cerevisiae biomass frombioethanol industrial waste. The research wasconducted using artificial wastewater withZn 2+ ion concentration of 300 ppm and the pHwas adjusted to the range between 3-7.Biosorption was conducted by addition of freeS. cerevisiae biomass as well as byimmobilized cells on filter paper. Observationwas carried out for Zn 2+ concentration aftercontact time of two and five hours. The resultsof the research indicated that free andimmobilized S. cerevisiae biomass couldabsorb Zn 2+ metal and decreased itsconcentration from 250-300 ppm to 20-50 ppm.The optimum contact time was reached at onehour, while optimum sorption process occurredat pH 5. At low concentration, less than20 ppm S. cerevisiae biomass absorbed lessZn 2+ The NaOH-treated biomass showed bettersorption capabilities compared to cells treatedby formaldehyde or heat treatments. Thecontinue experiment showed the high capacityof biomass treated with NaOH to absorb Zn 2+ ,until concentration 24,02- 47,95 ppm in thefirst sampling and 1,15-10,99 ppm in thesecond sampling. Combination adsorptionprocess using charcoal and zeolite couldadsorp remain concentration of Zn 2+ , so thatcould reached the limit concentration-allowed.RingkasanLogam berat di dalam air limbahmerupakan penyebab pencemaran lingkunganyang potensial. Pencemaran logam berat padaumumnya berasal dari industri penyepuhanlogam, tekstil, barang jadi lateks, serta industrilain. Pada proses industri barang jadi lateksdigunakan logam berat dalam bentuk ZnOsebagai akselerator proses vulkanisasi karet,sehingga ion Zn 2+ terbawa dalam air limbahindustri barang jadi dengan konsentrasimencapai 300 ppm, sedangkan ambang bataskonsentrasi yang diperbolehkan maksimaladalah 2,5 ppm. Cara kimia yang umum di-gunakan untuk menurunkan kandunganZn 2+ dalam air limbah adalah dengan caramenambahkan basa, umumnya NaOH atauCa(OH) 2 , sampai pH sekitar 11, sehinggalogam berat ini diendapkan sebagai hidroksida-nya. Namun demikian, cara ini sangat mahaldan beresiko munculnya pencemaran sekunderakibat kelebihan basa. Salah satu alternatifyang murah untuk penyerapan Zn 2+ adalahmenggunakan biosorben berupa biomassaSaccharomyces cerevisiae yang berasal darilimbah pabrik bioetanol.Penelitian dilakukan dengan mengguna-kan air limbah artifisial yang mengandung ionZn 2+ dengan konsentrasi 300 ppm. Limbahartifisial diatur pHnya antara 3-7. Biosorpsidilakukan dengan menambahkan biomassaS. cerevisiae bebas maupun yang diamobilisasidengan kertas saring. Pengamatan dilakukanterhadap kandungan Zn 2+ setelah waktu kontakdua dan lima jam. Hasil penelitian menunjuk-kan bahwa biomassa S. cerevisiae bebasmaupun amobil mampu menyerap logam Zn 2+dan menurunkan konsentrasinya dari 250-300 ppm menjadi 20-50 ppm. Waktu kontakoptimum dicapai setelah satu jam, sedangkanproses sorpsi optimum terjadi pada pH 5.Biomassa S. cerevisiae kurang efektifmenyerap logam Zn 2+ pada konsentrasi rendah,di bawah 20 ppm. Perlakuan biomassa meng-gunakan NaOH menunjukkan kemampuanpenyerapan yang lebih baik jika dibandingkandengan yang diperlakukan menggunakanformaldehida dan pemanasan. Percobaan padaaliran kontinyu yang menggunakan biomassayang diperlaukan menggunakan NaOH,menunjukkan bahwa limbah artifisial Zn 2+dapat diturunkan sampai konsentrasi 24,02-47,95 ppm pada sampling pertama, dan 1,15-10,99 ppm pada sampling kedua. Kombinasipenyerapan menggunakan arang aktif danzeolit dapat menyerap sisa Zn 2+ mencapai batasyang diperbolehkan.

scholarly journals Determination of the Cellular Ion Concentration in Saccharomyces cerevisiae Using ICP-AES

BIO-PROTOCOL ◽  
2020 ◽  
Vol 10 (16) ◽  
Author(s):  
Louise Thines ◽  
Anne Iserentant ◽  
Pierre Morsomme
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Ion Concentration

scholarly journals Energetics of Cd2+ efflux system in cadmium-resistant Staphylococcus aureus 17810R.

1995 ◽  
Vol 42 (1) ◽  
pp. 119-123
Author(s):  
Z Tynecka ◽  
A Malm
Keyword(s):  
Staphylococcus Aureus ◽  
Membrane Potential ◽  
Sodium Phosphate ◽  
Ion Concentration ◽  
Resting Cells ◽  
Efflux System ◽  
Phosphate Ion ◽  
Sodium Phosphate Buffer ◽  
High Phosphate

Energetics of 109Cd efflux in resting cells of cadmium-resistant Staphylococcus aureus 17810R was assayed in 1 or 100 mM potassium/sodium phosphate buffer, pH7 (PB). Experiments with the use of inhibitors and ionophores showed that Cd2+ extrusion in this organism required ATP and either a pH gradient (delta pH) in 1 mM PB or membrane potential (delta psi) in 100 mM PB. The role of high phosphate ion concentration in delta psi-dependent Cd2+ efflux is discussed.

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