Characterization of β-Galactosidase from Lactose Utilizing Yeast Isolated from the Dairy Sample
Bivek Dahal1#, Sujan Karki1#,
Nabaraj Adhikari2, Upendra Thapa Shrestha2, 3*
1 Universal
Science College, Pokhara University, Baneshwor, Kathmandu
2 Central
Department of Microbiology, Tribhuvan University, Kirtipur, Kathmandu
3 Research
Laboratory for Biotechnology and Biochemistry (RLABB), Kathmandu
# Both the
authors have equal contributions.
*Corresponding author: Upendra Thapa Shrestha, Central Department of Microbiology, Tribhuvan
University, Kirtipur, Kathmandu. Email: upendra.thapashrestha@cdmi.tu.edu.np
ABSTRACT
Objectives: The objective of the study was to isolate lactose positive yeasts from dairy samples collected from local markets of Kathmandu, to extract crude β-galactosidase from the lactose positive yeast and to characterize the enzyme for optimum time duration, pH, temperature, Michaelis-Menten constant (Km) and maximum activity (Vmax).
Methods: Four
lactose positive yeast strains were isolated from dairy samples collected from
local market of Kathmandu by pour plate method. Single strain having maximum
lactose positive activity was selected for the study. The mass culture of the
lactose positive yeast strain was lysed by 2% Chloroform and the yeast cell
lysate containing β-galactosidase (i.e. crude enzyme extract) was characterized
by using ONPG (Ortho-Nitrophenyl-β-D-galactopyranoside) as substrate. ONPG is a
colorless substrate for the enzyme assay which is hydrolyzed by the enzyme into
yellow colored product ONP (Ortho-Nitrophenol). The concentration of product
formed was monitored spectrophotometrically at 420 nm to determine the enzyme
activity and to characterize the enzyme.
Results: The
enzyme had wide range of working temperature from 0-50ºC, with optimal
temperature of 37ºC. However, greater than 50% hydrolyzing ability was
maintained in the range of 14-40ºC. Optimum time of reaction was 70 min. The
enzyme had maximum activity in the near-neutral pH of 6.8. Michaelis-Menten
constant of the enzyme was found to be 2.23 mM of ONPG and Vmax was 58.82 nmol/min/ml.
Enzyme activity was 27.88 nmol/min/ml, Specific enzyme activity was 59.97 nmol/
min/mg and total enzyme activity was 3346.33 nmol/min.
Conclusion: The
activity over a wide range of temperature 0-50ºC with low Km value shows that
the enzyme has a commercial application in clearance of lactose pollution in
wastewater in different environmental conditions.
Keywords: Yeast,
β-galactosidase, enzyme activity, ONPG, Km
DOI: https://doi.org/10.3126/tujm.v7i0.33874
Full text: Download
Hello everyone. I was heartbroken because i had very small penis, not nice to satisfy a woman, i had so many relationship called off because of my situation, i have used so many product which i found online but none could offer me the help i searched for. i saw some few comments about this specialist called Dr OLU and decided to email him on drolusolutionhome@gmail.com
ReplyDeleteso I decided to give his herbal product a try. i emailed him and he got back to me, he gave me some comforting words with his herbal pills for Penis t, Enlargement Within 5 day of it, i began to feel the enlargement of my penis, ” and now it just 2 weeks of using his products my penis is about 10 inches longer and am so happy..feel free to contact DR OLU on (drolusolutionhome@gmail.com) or whatsapp him on this number +2348140654426
How can i ever stop saying thank you to Dr olu
I really want to thank Dr Emu for saving my marriage. My wife really treated me badly and left home for almost 3 month this got me sick and confused. Then I told my friend about how my wife has changed towards me. Then she told me to contact Dr Emu that he will help me bring back my wife and change her back to a good woman. I never believed in all this but I gave it a try. Dr Emu casted a spell of return of love on her, and my wife came back home for forgiveness and today we are happy again. If you are going through any relationship stress or you want back your Ex or Divorce husband you can contact his whatsapp +2347012841542 or email emutemple@gmail.com website: Https://emutemple.wordpress.com/ Https://web.facebook.com/Emu-Temple-104891335203341
ReplyDelete
ReplyDeleteNaghahanap ako ng tulong sa internet upang maibalik ang aking dating asawa pagkatapos na hiwalayan niya ako 5 buwan na ang nakakaraan, napansin ko ang napakaraming mga patotoo mula sa iba't ibang mga tao at lahat sila ay nagsasalita tungkol sa kamangha-manghang taong ito na tinawag na Doctor AKHERE kung paano niya sila tinulungan upang makatipid ang kanilang kasal at mga relasyon at nakipag-ugnay din ako sa kanya sa kanyang email (AKHERETEMPLE@gmail.com) at ipinaliwanag sa kanya ang aking problema at gumawa siya ng isang magandang trabaho sa pamamagitan ng pagtulong sa akin na maibalik ang aking diborsyo na asawa sa loob ng 48 na oras .. Hindi ako naniniwala na ganoon ang mga bagay na tulad nito ay maaaring posible ngunit ngayon ako ay isang buhay na patotoo dito sapagkat talagang binalik ng Doctor AKHERE ang aking kasintahan, Kung mayroon kang anumang mga problema sa relasyon bakit hindi makipag-ugnay sa Doctor AKHERE para sa tulong sa pamamagitan ng email: AKHERETEMPLE@gmail.com o tumawag / whatsapp : +2349057261346
Pagkatapos ipinapangako ko sa iyo na pagkatapos ng 48 na oras magkakaroon ka ng mga dahilan upang ipagdiwang tulad ko.
Naghahanap ako ng tulong sa internet upang maibalik ang aking dating asawa pagkatapos na hiwalayan niya ako 5 buwan na ang nakakaraan, napansin ko ang napakaraming mga patotoo mula sa iba't ibang mga tao at lahat sila ay nagsasalita tungkol sa kamangha-manghang taong ito na tinawag na Doctor AKHERE kung paano niya sila tinulungan upang makatipid ang kanilang kasal at mga relasyon at nakipag-ugnay din ako sa kanya sa kanyang email (AKHERETEMPLE@gmail.com) at ipinaliwanag sa kanya ang aking problema at gumawa siya ng isang magandang trabaho sa pamamagitan ng pagtulong sa akin na maibalik ang aking diborsyo na asawa sa loob ng 48 na oras .. Hindi ako naniniwala na ganoon ang mga bagay na tulad nito ay maaaring posible ngunit ngayon ako ay isang buhay na patotoo dito sapagkat talagang binalik ng Doctor AKHERE ang aking kasintahan, Kung mayroon kang anumang mga problema sa relasyon bakit hindi makipag-ugnay sa Doctor AKHERE para sa tulong sa pamamagitan ng email: AKHERETEMPLE@gmail.com o tumawag / whatsapp : +2349057261346
Pagkatapos ipinapangako ko sa iyo na pagkatapos ng 48 na oras magkakaroon ka ng mga dahilan upang ipagdiwang tulad ko.
i am here to give my testimony about a doctor who save my life. i was infected with HERPES for than 2 years, I tried different doctors over a period of time but no one work, but when i came on the Internet i saw great testimony about DR USELU how he was able to cure someone from HERPES virus with the help of herbal medicine I contacted him and he promised to cure my herpes virus.well i decided to give him a try, DR USELU put his best in it and gave me good and effective result just as he has promised. well after taking all the treatment sent to me by Dr USELU i went back to the Hospital for check up, and now i have been confirmed HERPES Negative. You can contact him if you have any kind of sickness like, HERPES, HIV, CANCER, PILE, HEPATITIS, DIABETES, and alot more you can contact him ON Whatsapp (+2347052898482) or Email dr.dr.uselucaregiver@gmail.com
ReplyDeleteI am so happy, i never believe i will be this happy again in life, I was working as an air-hoster ( cabby crew ) for 3years but early this year, i loose my job because of this deadly disease called Herpes virus (HSV), I never felt sick or have any symptom, till all workers were ask to bring their doctor report, that was how i got tested and i found out that am HSV positive that make me loose my job, because it was consider as an STD and is incurable disease, i was so depress was thinking of committing suicide, till i explain to a friend of mine, who always said to me a problem share is a problem solved, that was how she directed me to DR.USELU, that was how i contacted him and get the medication from this doctor and i got cured for real, I just went back to my work and they also carry out the test to be real sure and i was negative. Please contact this doctor if you are herpes positive or any STD diseases his email is: dr.uselucaregvier@gmail.com or you can call or whatsApp his mobile number on +2347052898482
ReplyDeleteI can’t believe this. A great testimony that i must share to all HERPES SIMPLEX VIRUS patient in the world i never believed that there could be any complete cure for Herpes or any cure for herpes,i saw people’s testimony on blog sites of how Dr OKITI prepare herbal cure and brought them back to their normal health again. i had to try it too and you can't believe that in just few weeks i started using it all my pains stopped gradually. Right now i can tell you that few months now i have not had any pain, and i have just went for test last week and the doctor confirmed that there is no trace of any herpes system in my body. Glory be to God for leading me to this genuine Doctor Dr OKITI I am so happy as i am sharing this testimony. My advice to you all who thinks that there is no cure for herpes that it's Not true, Here is his email: drokitiherbalherbalhome100@gmail.com or WhatsApp number +1 (484) 393‑5484
ReplyDeleteNatural Herbal Medicine To Cure {HERPES DISEASE} TOTALLY HERE
ReplyDeleteDo you need a solution to cure your Herpes Disease contact Chief Dr Lucky to help and he will surely help you to cure your Herpes Virus .. I have suffered from Herpes-2 Virus for 4years ago that almost took my life. But one day I was searching the internet and I found Chief Dr Lucky saw so many testimonies on how Chief Dr Lucky helps people in curing their deadly diseases, and I contacted Chief Dr Lucky, asked him for solutions and he started the remedies for my health. He prepared herbal medicine for me and I received the herbal medicine and after using it for 2 weeks my condition has greatly improved, all my symptoms including Abdominal pain, Nausea and vomiting, Loss of appetite stopped, so I went to my doc and was confirmed negative. I am Herpes Virus free! contact the herbal doctor via his email> chiefdrlucky@gmail.com also visit his page> http://facebook.com/chiefdrlucky or his cell number / WhatsApp> +2348132777335
I lost my job few months back and there was no way to get income for my family, things was so tough and I couldn't get anything for my children, not until a met a recommendation on a page writing how Mr Bernie Wilfred helped a lady in getting a huge amount of profit every 6 working days on trading with his management on the cryptocurrency Market, to be honest I never believe it but I took the risk to take a loan of $800 and I contacted him unbelievable and I was so happy I earn $12,500 in 6 working days, the most joy is that I can now take care of my family I don't know how to appreciate your good work Mr. Bernie Doran God will continue to bless you for being a life saver I have no way to appreciate you than to tell people about your good services.
ReplyDeleteFor a perfect investment and good strategies contact Mr Bernie Doran via WhatsApp :+1(424)285-0682 or Telegram : @Bernie_doran_fx or Email : Bernie.doranfx01@gmail.com