fermentation

Class : Biomass Technology and Production.
Lecture :  Pak Ngadiman
March, 24th 2015.

FERMENTATION

Fermentation have two meaning, first from "Microbiologist" and second from "Biochemist".
From Microbiologist, fermentation is any process for the production of a product by the mass culture of microorganism.
From Biochemist, fermentation is an energy generation process in which organic compound act as both electrons donor and acceptor that is anaerobic process.

Fermentation basis.
This is an picture of growth microorganism.

 

source : http://academic.pgcc.edu/~kroberts/Lecture/Chapter%206/06-20_MicrobialGrowth_L.jpg

There are four phase of growth microorganism.

From here, can determine, what the phase what you will take the result.

If you just need primary metabolite, so you just need the log phase. In these phase, the microorganism have higher activity. They will grow maximal. Primary metabolite is produce product for biomass cell. Example : If you need cellulose, you can take in log phase (middle until end phase).

But, if you need secondary metabolite, you must wait until stationary phase. Microorganism product secondary metabolite when they in stress environment so they produce that for survive their live. In stationary phase, the microorganism also have an sustainability about grow and death.

stationary phase > grow = death

Secondary metabolite that can produce in stationary phase is not for cell biomass of bacteria. Secondary metabolite also sensitive with external factors.

bagaimana cara memutus kapilaritas air?

Kapilaritas merupakan suatu peristiwa naik atau turunnya suatu zat cair dalam suatu pipa kapiler. 

Salah satu contoh zat cair disini adalah air. Air selain yang kita jumpai di permukaan tanah, ternyata ada juga air yang di dalam tanah. Air tanah mampu menembus permukaan tanah dan juga air dari permukaan tanah bisa masuk ke dalam tanah. Mungkin ketika air permukaan tanah dapat masuk ke dalam tanah bisa disebabkan oleh infiltrasi. Hal ini disebabkan oleh gaya gravitasi. Tetapi ada kalanya ada air tanah dapat naik ke permukaan. Bagaimana bisa?

Hal ini disebabkan dalam tanah terdapat pori tanah. Nah pori tanah itu kecil jadi dapat dianalogikan sebagai pipa. Kita mengenal berbagai macam jenis tanah nih, seperti tanah lempung (clay), tanah pasir (sand). Tetapi ada juga tanah ideal yang merupakan komposisi ideal dari keduanya, yaitu tanah loam. 

Sebenernya aku pengen cerita aja sih, jadi tadi kan aku dapat kelas Pengelolaan Air, dengan dosen Pak Anjal. Nah, bapaknya cerita tentang suatu masyarakat di entah mana aku lupa, dia berhasil memotong kapilaritas air. Bagaimana ceritanya? Sebenarnya masyarakat itu adlaah petani biasa, tapi beliau berdasarkan pengalaman dan hasil coba-coba beliau berhasil memotong ikatan kapiler air tanah. Hasil coba-coba beliau berhasil menyelamatkan kakao karena kekeringan yang terjadi, dimana kakao milik masyarakat lain banyak yang mati, tapi punya beliau masih bertahan hidup.

Ternyata oh ternyata bapak tersebut hanya meng-"kesrik" atau mencangkul dangkal pada permukaan tanah disekeliling tanaman kakao.

Bagaimana hal sepele seperti itu dapat menyelamatkan kakao? Hanya dengan meng"kresik" tanah disekitarnya? Nah, dengan adanya mengkresik tanah disekitar pohin kakao, ini ternyata dia dapat memutus kapilaritas air. Kapilaritas air yang seharusnya naik terus ke permukaan, dengan adanya sedikit pengolahan, maka dia tidak langsung ke permukaaan. Hal ini disebabkan dengan adanya pengolahan tanah, maka mengakibatkan pori tanah menjadi lebih besar.

 

http://www.daviddarling.info/images2/capillarity.jpg

Penjelasannya ada disini, ketika pori  tanah kecil maka kecepatan kapilaritas air sangat cepat, sedangkan pada saat pori tanah besar, maka pori tanah besar.

Wah keren ya bapaknya.. Point, hari ini, bergurulah pada siapa aja, hehe...

Cryoprotectants

Cryprotectants is a compound that used to formed glass.

Cryoprotectants: the essential antifreezes to protect life in the frozen state. In the fifty years since the establishment of the cryoprotective effect of glycerol, cell banking by cryopreservation has become routine in many areas of biotechnology and medicine. Cryoprotectant addition has become a rather mundane step within the overall protocol. However, for future advances in cryobiology and to meet new challenges in the clinical use of cryopreserved cells or tissues, it will be essential to have an understanding of the development and current status of the biological and chemical knowledge on cryoprotectants (CPA). This review was undertaken to outline the history of CPA use, the important properties of CPA in relation to freezing damage, and what can be learnt from natural freezing-tolerant organisms. The conflicting effects of protection and toxicity resulting from use of CPA are discussed, and the role of CPA in enhancing glassy states in the emerging field of vitrification are also set out. 

source : Fuller, B.J. 2004. Cryoprotectants: the essential antifreezes to protect life in the frozen state. Cyro Letters 25 : 375-388.

 Yeah, today I study about cryoprotectants. From the explain my lecture, I curios about honey. I think honey is a thing that can used as cryoprotectants. Why I think like that? I read an article last, there were explain that honey cannot be freeze. I think, in honey have an cryoprotectants. It is so simple right? Honey cannot be freeze, cryoprotectans is a compound that uses formed glass. I think, there are related.

But, unfortunately, when I search one article for reference, my hipotesis is break !! read it..

On a final note, you might also notice that, over time, honey tends to crystallise and solidify. Because honey’s water content is so low, it can be considered to be a super-saturated solution of the various sugars; a solution is considered saturated when as much solid as is possible has been dissolved in it. Over time, glucose will precipitate out of the solution, forming solid crystals. The honey is still perfectly fine to eat, and this doesn’t constitute spoilage – to revert it back to its liquid form, all that’s required is immersion in warm water for a few minutes. 

source : http://www.compoundchem.com/2014/08/21/chemistryofhoney/

Okay, fine! Lets imagine again :p