Regijsko srečanje mladih raziskovalcev 2020
Obdelava mlekarskih odpadnih vod z algami
Šola: Biotehniški center Naklo
Avtorica: Klara Žos
Mentor: Borut Lazar
Zaradi pospešenega gospodarskega razvoja v zadnjih letih vedno več materialov in surovin pristane v okolju v obliki odpadnih snovi. Med slednje spadajo tudi odpadne vode. Mlekarske odpadne vode vsebujejo visoke koncentracije organskih in anorganskih snovi, ki lahko ob izpustu v naravni ekosistem porušijo njegovo ravnovesje.
V raziskavi sem preučevala, kako lahko z uporabo algnih tehnologij razbremenimo mlekarske odpadne vode. Ugotovila sem, da alge učinkovito znižajo količino fosfatov, amonij pa v procesu nitrifikacije pretvorijo v nitrate in nitrite.
Tehnike čiščenja mlekarskih in drugih odpadnih vod bi lahko tako z izboljšanjem njihove učinkovitosti uporabljali širše. Na ta način bi manj obremenjevali okolje, alge pa so tudi uporabna izhodna surovina za industrijske ali druge procese, tudi za proizvodnjo biogoriv.
With accelerated economic development, more and more materials end up as waste. This also applies to wastewater. In particular, wastewater in the dairy industry has high concentrations of organic and inorganic substances, which can cause environmental degradation.
I researched how algae technologies can handle dairy wastewater. The results show that algae can reduce phosphate concentrations and convert ammonium to nitrates and nitrites through the process of nitrification and denitrification.
Such technology could be used on a larger scale. This would cause minor environmental damage and further algae biomass could be used for industrial use or even biofuels.
Mikrobiološka analiza športnih bidonov
Šola: Biotehniški center Naklo
Avtorji: Nejc Bucalo, Ambrož Gantar, Cene Hafner
Mentorica: mag. Marjetka Kastelic Švab
V današnjem času ima skoraj vsaka oseba za pitje pri sebi steklenico, plastenko ali bidon, ki je namenjen za vsakdanjo uporabo. Ljudje se ne zavedamo kaj vse se lahko naseli v naše plastenke v primeru, da je po uporabi ne očistimo dovolj temeljito in kako je to lahko nevarno. Zelo hitro lahko zbolimo, ne vede kaj je vzrok za to.
Z raziskovalno nalogo smo želeli ugotoviti ali je v uporabljenih bidonih prisoten kakšen patogen mikroorganizem, ki bi potencialno lahko ogrožal posameznikovo zdravje in kako bi se ga lahko na čim bolj preprost način znebili.
V raziskovalni nalogi smo se odločili, da bomo uporabili za vzorčne primere športne bidone, ki jih uporabljajo pri hokeju in ragbiju. Vseh vzorčnih bidonov je bilo skupaj dvajset. V nekaterih bidonih je bila vedno natočena in izpita le voda, v drugih pa tudi sladke pijače in celo proteinsko bogati napitki. Z raznovrstnostjo izbire športnih bidonov smo želeli dokazati prisotnost različnih mikrobnih kultur.
Pri delu je bilo izvedeno veliko mikrobioloških laboratorijskih tehnik: aseptično delo, odvzem vzorca, vzorčenje z izpirki, izolacija in gojenje kulture, pipetiranje, tehtanje, priprava gojišč, tehnika difuzijskega antibiograma, katera je bila uporabljena za določanje občutljivosti vzorčne kulture na potencialno zaviralne snovi.
Na koncu smo prišli do ugotovitev, da na plesni iz rodov Aspergillus, Penicillium in Phoma najbolj zaviralno deluje alkoholni kis. Jabolčni kis je zaviral rast rodov Phoma in Penicillium, medtem ko je 40 % etanol zavrl le rod Aspergillus. Ekstrakt jabolčnih pešk in citronska kislina nista zavirala rasti nobene plesni.
Nowadays, almost every person has his/her own bottle for everyday use. People were unaware of what could settle into our bottles, if we do not clean it properly after use and how dangerous that can be. We could get sick very quickly without knowing what coused it. In our research project we wanted to determine if any pathogenic microorganism was present in the used bottles, which could potentially threaten people health and how to get rid of it in the most simple way.
For the research assignment, we decided that we are going to use the sports bottles brought from hockey and rugby as role models. There were a total of twenty sample bottles. In some of bottles there was only water and in the others sweet drinks and even protein rich beverages. With diversity, we wanted to acquire more different cultures.
Many microbiological laboratory techniques were performed at the work: aseptic work, sample collection, isolation into culture cultivation, pipetting, weighing, preparation of culture media, diffusion antibiogram technique used to determine sensetivity of the culture against potential
inhibitory substances.
In the end we figured out that spirit vinegar hinders fungus from genuses Aspergillus, Penicillium and Phoma. Apple cider vinegar hindered genuses Phoma and Penicillium, while 40% ethanol hindered just genus Aspergillus. Extrakt from apple seeds and citric acid did not hindered any of fungus.
Dokazovanje antimikotičnega delovanja vodnih ekstraktov na kvasovko Candida albicans
Šola: Biotehniški center Naklo
Avtorice: Lara Markelj, Neža Perko, Maša Repinc
Mentorica: mag. Marjetka Kastelic Švab
Candida albicans (C. albicans) je gliva kvasovka, ki pri človeku povzroča mikoze oziroma glivične okužbe. C. albicans je del naše naravne mikrobiote, nahaja se v ustni votlini, sluznicah trebušne votline in spolovil, vendar vpliv različnih dejavnikov, največkrat padec odpornosti, lahko poruši ravnovesje v našem telesu in število teh oportunističnih gliv naraste. Tako lahko postanejo zajedavske in praviloma še bolj oslabijo naš imunski sistem in lahko napadejo tudi respiratorne organe.
Glavni namen raziskovalne naloge je sestaviti čim ugodnejše gojišče za uspešno kultivacijo C. albicans in s pomočjo difuzijskega antibiograma odkriti različne antimikotične učinkovine, ki naj bi zaviralno delovale na rast glive C. albicans.
Praktični del smo pričeli s pridobivanjem brisov sluznic ustnih votlin oseb, ki naj bi trpele za kandidozo. Vzorce smo nato prenašali na različno pripravljena sestavljena gojišča, kajti poleg izoliranja čiste kulture, so nas zanimali tudi vplivi različnih gojišč in različnih spodbujevalcev rasti (kave in mleka) na uspešnejšo razrast C. albicans. Opravili smo tudi pregled morfoloških značilnosti kolonij C. albicans in identifikacijo le te s pomočjo klaisčnih identifikacijskih morfoloških in biokemijskih metod (katalazni test, enostavno barvanje z metilenskim modrilom in mikroskopiranje). Z metodo difuzijskega antibiograma smo ugotavljali antimikotično delovanje treh potencialnih učinkovin, ki naj bi zavirale rast kandide, perkolata grenivkinih pešk, perkolata zelenega čaja ter ekstrakta domačega propolisa. Dilucijski antibiogram smo izvajali na PDA gojišču z dodatkom krvi in antibiotika. Ugotovili smo, da perkolat zelenega čaja ni zaviral rast kandide. Zaviralen učinek je bil prisoten pri ekstraktu grenivkinih pešk, največji pa pri propolisu, pri katerem so bile inhibicijske cone največje.
Candida albicans (C. albicans) is a yeast fungus that causes mycosis or fungal infections in humans. C. albicans is a part of our natural microbiota, it is found in the oral cavity, mucous membranes of the abdomen and genitals, but the influence of various factors, most often a weakened immune system, can break the balance in our body and the number of these opportunistic fungi increases. As a result, they can become parasitic and, as a rule, further weaken our immune systems and can attack the respiratory organs as well.
The main purpose of this research paper is to construct the most appropriate medium for the successful cultivation of C. albicans and to identify, through a diffusion antibiogram, various antifungal substances, which are supposed to have an inhibitory effect on C. albicans.
The practical part started with taking oral mucous swabs of people who are supposed to suffer from candidiasis. The samples were then transferred to differently prepared composed media, because apart from isolating the pure culture, we were also interested in the effects of different media and different growth stimulator (coffee and milk) on the more successful growth of our culture. We also examined the morphological characteristics of C. albicans colonies and identified them by using biochemical identification methods (a catalase assay, simple staining with methylene blue and microscopy). The method of diffusion antibiogram was used to determine the antifungal activity of three potential substances that are expected to inhibit the growth of candida: perchlorate of grapefruit seed, perchlorate of green tea and the concoction of homemade propolis. Diffusion antibiogram was performed on PDA medium supplemented with blood and antibiotic. We have found out that green tea percolate did not inhibit candida growth. The inhibitory effect was present in grapefruit pawn extract and the greatest in propolis, where the inhibition zones were the highest.
Konkurenčnost probiotičnih sevov rodu Bacillus na patogeno črevesno bakterijo Escherichia coli
Šola: Biotehniški center Naklo
Avtorice: Nika Drinovec, Maruša Godler, Lara Ropič Bizjak
Mentorica: mag. Marjetka Kastelic Švab
V našem črevesju najdemo raznovrstno mikrofloro, ugodne kot škodljive mikroorganizme. Med ugodnimi bakterijami spadajo tudi probiotiki oziroma probiotične bakterije, ki našim prebavilom pomagajo pri presnavljanju hrane, sintetizirajo vitamine, aminokisline in maščobne kisline, skrbijo za peristaltiko in preprečujejo naselitev patogenim mikroorganizmom v črevesju. Poleg našega črevesja, jih najdemo v mlečnih izdelkih, prehranskih dodatkih, v še večjih količinah pa skoncentrirane v probiotičnih zdravilih. Probiotiki podpirajo razvoj in delovanje našega imunskega sistema. Sintetizirajo protimikrobne snovi, ki ovirajo preživetje in razvoj škodljivih bakterij. V raziskovalni nalogi smo preučevali ali bi lahko probiotike uporabljali kot vzporednica antibiotikom, v smislu zaviranja rasti in razmnoževanja patogenih mikroorganizmov kot sta lahko Escherichia coli (E. coli) in Salmonella typhi. To vprašanje je bilo povod naši raziskovalni nalogi. Najprej smo izolirali E. coli iz hlevskega gnoja (bakterije rodu Salmonella nam ni uspelo izolirati) in jo namnožili na optimalnem gojišču za rast– EMB gojišču. Probiotične seve Bacillus smo pridobili iz kapsul MegaSporeBiotic. V raziskovanju smo se posvetili iskanju in pripravi pravega, najugodnejšega gojišča za ugotavljanje konkurenčnosti, na katerem uspevajo tako bakterije E. coli kot probiotični rod Bacillus (Bacillus licheniformis, Bacillus coagulans, Bacillus indicus HU36, Bacillus subtilis HU58, Bacillus clausli). Ugotovili smo, da z mešanjem EMB in CBL gojišč, dobimo zelo ugodne razmere za rast in razmnoževanje obeh vrst kultur. Kulture smo po uspešni izolaciji do čistih kultur, aseptično prenesli na gojišča paralelk v približno enakem razmerju, kot jih najdemo v naravnem okolju. V času inkubacije smo na dva dni opazovali razrast obeh kultur. Ugotovili smo, da probiotiki rodu Bacillus lahko delujejo zaviralno na E. coli, torej inhibirajo rast le teh v ugodnih razmerah patogenih bakterij in s tem preprečujejo njihovo večjo razrast in posledično povzročanje bolezni.
We can find a very diverse microflora in our body, specifically in our intestines. From good microorganisms to harmful ones. Good bacteria include probiotics that is also known as probiotic bacteria which help us process food, synthesize vitamins, amino acids and fatty acids, they take care of our peristalsis etc. Beside in our intestines, we can also find them in dairy products, nutritional supplements, and in even greater quantities in probiotic medicines.
Probiotics also support development in our immune systems and its activity. More specifically they synthesize antimicrobials that obstruct the survival and the development of harmful bacteria. We were wondering if probiotics could be used as antibiotics to decelerate the growth and reproduction of pathogenic bacteria such as Escherichia coli in Salmonella typhi. This question became the basis of our research.
We first isolated E. coli from manure (we could not isolate the bacteria Salmonella) and multiplied it on the most favorable medium – EMB medium. Probiotics were obtained from MegaSporeBiotic capsules. We sought a common medium for successful growth of both E. coli and Bacillus (our probiotics; Bacillus licheniformis, Bacillus coagulans, Bacillus indicus HU36, Bacillus subtilis HU58, Bacillus clausli). We have found that by mixing EMB in CBL mediums, you get a very favorable growth environment for the propagation of those two cultures. The cultures were aseptically transferred to the medium in an approximate ratio as found in the natural environment and incubated. We observed the numbers of colonies of both cultures every second day since the incubation.
We have come to the conclusion that probiotics can be used as ainhibitors and inhibit the growth of pathogenic bacteria, thereby preventing their infections.
Vpliv sirotkinega proteina na prirast biomase kefirnih zrn
Šola: Biotehniški center Naklo
Avtorice: Anja Kozjek, Ana Jenc, Janja Sikošek
Mentorica: Tadeja Polajnar
V nalogi so predstavljeni izsledki raziskave vpliva sirotkinega proteina na prirast biomase kefirnih zrn. Poskus je bil izveden z dvema različnima koncentracijama sirotkinega proteina 2 in 6 % (5 g predstavlja 2 %, 15 g predstavlja 6 %) v dveh različnih vrstah mleka (1,5 in 3,5 % m. m.). Fermentacija je bila ponovljena večkrat, pri tem pa je bila spremljana masa kefirnih zrn, število mlečnokislinskih bakterij, kvasovk ter sprememba pH in kislinske stopnje po Soxhlet-Henklu med mlečnokislinsko fermentacijo.
Največji prirast mase kefirnih zrn je bil dosežen pri fermentaciji delno posnetega mleka z 1,5 % m. m. z dodatkom (2 %) sirotkinih beljakovin. Sledil je prirast mase kefirnih zrn pri fermentaciji mleka z enako količino maščobe in z dodanimi (6 %) beljakovinami.
Največje povečanje količine mlečnokislinskih bakterij je bilo zabeleženo pri fermentaciji delno posnetega mleka (1,5 % m. m.) z dodanima 2 % sirotkinih beljakovin. Največje povečanje kvasovk pa pri fermentaciji polnomastnega mleka (3,5 % m. m.) s 6 % sirotkinih beljakovin. Torej je skupno število mikroorganizmov v kefirnem zrnu naraslo, nekje na račun mlečnokislinskih bakterij, nekje pa na račun kvasovk. Iz tega je moč sklepati, da se mlečnokislinske bakterije razmnožujejo intenzivnejše v okolju z manj maščobe (1,5 % m. m.) in z manjšo koncentracijo sirotkinih beljakovin (2 %). Kvasovke pa se intenzivneje razmnožujejo v okolju z več maščobe (3,5 % m. m.) in višjo koncentracijo sirotkinih beljakovin (6 %).
Z opazovanjem spreminjanja pH-vrednosti je bilo dokazano, da je najbolj intenzivna fermentacija potekla pri vzorcu 1,5 % m. m. z dodanima 2 % sirotkinih beljakovin, glede na spremembo kislinske stopnje pa pri vzorcu 1,5 % m. m. in 6 % dodatka sirotkinih beljakovin.
The research was based on finding out the positive effects of whey protein on the biomass of kefir grains after fermentation. The experiment was executed with two different concentrations of kefir grains (2 and 6 %, 5 g represents 2 % and 15 g presents 6 %) in two different types of milk (low fat milk- 1,5 % milk fat, and whole milk- 3,5 % milk fat). This fermentation was repeated multiple times, during which we observed the change in the biomass of kefir grains, the number of lactic acid bacteria, the number of yeast cells, pH rate change and SH rate change during the entire fermentation process.
The highest mass increase was reached with kefir made from low fat milk with added 2 % of whey protein, the second one with the biggest increase was seen to be the one made from low fat milk with added 6 % of whey protein.
The biggest increase in number of lactic acid bacteria was recorded at kefir made from low fat milk with added 2 % of whey protein. The biggest increase in number of yeast was recorded at kefir made from whole milk with added 6 % of whey protein. The total number of microorganisms in kefir had therefore increased after fermentation. In one sample it was increased at the expense of lactic acid bacteria and in the other at the expense of yeast.
Due to these results we can derive that lactic acid bacteria reproduce better in an environment which contains less milk fat (in low fat milk) and lower concentration of whey protein (2 %). What can also be seen is that yeast reproduces better in an environment with a higher milk fat concentration (whole milk) and higher concentration of whey protein (6 %).
Looking at the pH rate results the highest fermentation intensity was in the sample with 1,5 % milk fat and added 2 % of whey protein.
SH value was detected highest in the sample made of milk with 1,5 % of milk fat with added 6 % of whey protein.
Določanje makrohranil in mikrohranil pri živilih, primernih za ledvične bolnike
Šola: Biotehniški center Naklo
Avtorji: Eva Bečan, Nina Borštnar, Luka Zorman
Mentorica: Maša Škrlep
Prehrana je pri ledvičnem bolniku zelo pomembna, saj pripomore k temu, da si bolnik ne poslabša stanja bolezni in da lahko njegovo zdravljenje lažje napreduje. Kronična ledvična bolezen pomeni okvaro strukture ali delovanja ledvic, ki traja več kot tri mesece. Ker kronična okvara sčasoma povzroči slabšanje ledvičnega delovanja, jo lahko poimenujemo tudi kronično ledvično popuščanje. Večje tveganje za obolevanje imajo sladkorni bolniki, kadilci, predebeli, starejši (nad 60), ljudje z boleznimi srca in ožilja in zvišanim krvnim tlakom. Ker ledvice same ne morejo opravljati primarne naloge, čiščenja krvi, je potrebno zdravljenje z dializo, ki jo delimo na hemodializo in peritonealno dializo. Bolniki na dializi so prikrajšani za normalno življenje, kar lahko, zaradi psihičnih in fizičnih dejavnikov, privede do izgube volje do življenja in premajhne telesne aktivnosti, zato je zelo pomembno, da je njihova prehrana prilagojena in ne vodi v podhranjenost. Namen naloge je bila izdelava gradiva za dializne bolnike. Za metodo dela smo uporabili spletno apklikacijo Odprta platforma za klinično prehrano (OPKP). V tej platformi smo iskali različna živila, ki bodo primerna za ledvične bolnike. Podatke o energijski vrednosti, makrohranilih in mikrohranilih, ki smo jih pridobili smo prenesli v Excel tabelo in uredili glede na razmerje med beljakovinami in fosforjem, ki sta pomembna kazalnika za ledvične bolnike. Rezultate smo primerjali s hipotezami, ki smo jih deloma ovrgli.
Nutrition is very important when someone is suffering with kidney disease, because it helps to prevent the decline of state of the disease and makes it easier to improve patient’s health. Chronic kidney disease (CKD) means a defect of the structure or the function of kidneys, that lasts more than three months. Because chronical impairment leads to impaired renal functionality over time, it can also be called chronic renal failure. People, who are most likaly to get CKD are diabetics, smokers, people, who are obsess, older people (over 60), people, whose relatives also have CKD, people with cardiovascular diseases and people, who struggle with high blood pressure. Dialysis treatment is necessary, because kidneys can not purify that amount of blood. The treatment type may be hemodialysis or peritoneal dialysis. Due to mental and physical factors (loss of will to live and lack of physical activity) is even more important, that their diet is adjusted. The purpose of the assignment was to explore which micronutrients and macronutrients are present in frequently consumed food. As the metod of our work, we used the program Open Platform for Clinical Nutrition (OPEN). In this platform, we searched for different foods, that would be suitable for kidney patients. We transferred the data, that we have gathered, to Excel spreadsheet and edited it. Refuted hypotheses helped us to come along the results.
Uporaba energijskih pijač med dijaki Biotehniškega centra Naklo
Šola: Biotehniški center Naklo
Avtorice: Marjeta Podobnik, Nika Bajd, Katarina Kovač
Mentorica: Vanja Šubic
Energijske pijače so brezalkoholne osvežilne pijače s sestavinami kofein, tavrin, glukoronolakton in ostalimi sestavinami, ki naj bi vplivale na naš centralni živčni sistem in nas oskrbele z energijo. Večina jih vsebuje tudi velike količine sladkorja ali sladil, rastlinske izvlečke in vitamine. Študije so pokazale, da imajo energijske pijače negativne učinke na zdravje. Raziskava Evropske agencije za varno hrano je pokazala, da te pijače najpogosteje uživajo najstniki, stari od 10 do 18 let.
Z raziskavo smo želeli ugotoviti, koliko dijakov Biotehniškega centra Naklo posega po energijskih pijačah, kakšen je razlog in katere znamke kupujejo. Raziskavo o porabi energijskih pijač med dijaki smo izvedle s pomočjo anketnega vprašalnika. V raziskavo smo zajele 578 od 833 dijakov naše šole. 408 ji uživa energijske pijače, to je 71 % anketiranih dijakov. Slaba polovica teh po energijskih pijačah seže le ob posebnih priložnostih, vendar pogosto v kombinaciji z alkoholom. Dobra četrtina dijakov poseže po energijskem napitku od enkrat do večkrat mesečno, slaba četrtina pa od enkrat do večkrat tedensko. 21 dijakov jih uživa vsak dan. Dijaki še navajajo, da je glavni razlog uživanja okus pijače, od blagovnih znamk pa najbolj segajo po Red Bullu.
Glede na veliko število dijakov, ki segajo po energijskih pijačah, se postavlja vprašanje, koliko dijaki vedo o njihovi škodljivosti. Predlagamo, da se zato na šolah izvajajo predavanja o nevarnostih, ki jih prinaša uživanje energijskih pijač.
Energy drinks are nonalcoholic drinks containing caffeine, taurine, glucuronolactone and other ingredients which claim to effect the central nervous system and supplement us with energy. Most of those drinks additionally include great amounts of sugar or sweeteners, plant extracts and vitamins. Studies have demonstrated the negative health effects of those drinks. Research by European Agency for Food Safety showed most energy drinks are consumed by the adolescents aged 10 to 18.
Our research focused on how many students from Biotechnology center Naklo consumes energy drinks, what’s their motivation and which brands do they consume. We conducted our research using a questionnaire. We included 578 out of 833 students of our school. Out of 578 students questioned, 408 consumes energy drinks, which is 71%. A bit less than a half of those questioned consume energy drinks only on special occasions, however, often times in combination with alcohol. A bit more than a quarter of students consumes energy drinks from one to a few times a month. A bit less than a quarter consumes drinks from one to a few times a week. 21 students questioned consume energy drinks on a daily basis. Based on the answers in the questionnaire, the primary reason for consuming the energy drinks is their flavor, while the most consumed brand is Red Bull.
Given the large number of students drinking energy drinks, one can raise a question how many students are aware of the dangers associated with consumption of energy drinks. We recommend schools to have an educational lecture about the dangers brought about by drinking energy drinks.
Senzorična kakovost in mikrobiološka varnost spontano fermentiranega korenja
Šola: Biotehniški center Naklo
Avtorice: Anja Šubic, Manca Selak, Nika Zaplotnik
Mentorica: Vanja Šubic
Cilj naše raziskovalne naloge je ugotoviti, ali je mogoče izdelati senzorično ustrezno in mikrobiološko varno fermentirano zelenjavo, pripravljeno s spontano mlečnokislinsko fermentacijo, in kakšno vlogo ima pri tem koncentracija kuhinjske soli v slanici. Korenje iz konvencionalne pridelave smo zrezali na ploščice, debeline 2 mm, jih polnili v steklene kozarce, razdelili na 5 šarž in zalili z 1 %, 2 %, 3 %, 4 % in 5 % slanico. Mlečnokislinsko fermentacijo, ki je potekala na sobni temperaturi, smo spremljali z merjenjem topne suhe snovi in pH-vrednosti. Po končani fermentaciji smo določali število enterobakterij na gojiščih VRBD in EMB. Analiza na prisotnost enterobakterij je bila pozitivna, zato smo število prisotnih enterobakterij skušali zmanjšati z dodatkom zelnice. Ob tem smo merili tudi število mlečnokislinskih bakterij na gojišču MRS.
Rezultati analiz kažejo, da koncentracija soli ne vpliva na potek mlečnokislinske fermentacije. V vseh vzorcih smo dosegli pH-vrednost pod 3,7, vendar to ni zagotovilo mikrobiološke varnosti. Najnižje število enterobakterij smo ugotovili v vzorcu s 4 % slanico, ki ima istočasno najvišje število mlečnokislinskih bakterij, ki so morebiti preprečile razrast enterobakterij. Sklepamo, da je število mlečnokislinskih bakterij pomembnejši pokazatelj varnosti izdelka kot pH-vrednost, zato za pripravo fermentiranih izdelkov priporočamo uporabo kultur mlečnokislinskih bakterij, ki zagotavljajo uspešen potek fermentacije in varen končni izdelek.
The aim of our research assignment was to assess whether it is possible to produce sensorially viable and microbiologically safe fermented vegetables through the process of spontaneous lactic acid fermentation and the role of salt concentration in the process. We cut conventionally grown carrots were to plates of thickness 2 mm and put them in glass containers. We split them in 5 batches and filled them with 1, 2, 3, 4, and 5% salt solution. The batches were stored at a room temperature. We followed the process of lactic acid fermentation by measuring solvable dry mass and pH-value. After the fermentation process finished, we assessed the number of enterobacteria on VRBD and EMB media. The analysis showed the presence of enterobacteria, which is why we tried to reduce the number of enterobacteria by adding fermented cabbage juice. Alongside, we also measured lactic acid bacteria on the MRS media.
The results of the analysis show that salt concentration had no effect the lactic acid fermentation. All samples achieved a pH-value below 3,7, which, however, did not ensure microbiological safety. The lowest count of enterobacteria was found in the batch with 4% salt solution. The same batch also had the highest number of lactic acid bacteria, which might have suppressed the multiplication of enterobacteria. Based on that we postulate that the amount of lactic acid bacteria is a more important indicator of the product safety as the pH value. Thus, we recommend the use of lactic acid culture in the preparation of fermented products since they ensure a successful fermentation process and a safe final product.
Kakovost pitne vode
Šola: Biotehniški center Naklo
Avtorici: Vanja Benedik, Natalija Dolinar
Mentorica: Kristina Frlic
V nalogi je predstavljena mikrobiološka analiza vode iz domačega zajetja, v kateri smo ugotavljali skupno število mikroorganizmov pri 22 °C in 37 °C, prisotnost koliformnih mikroorganizmov, bakterije E. coli, enterokokov in plesni ter skladnost vzorcev s pravilniki.
Vzorci vode so bili odvzeti iz kuhinjske pipe, kjer priteče voda iz domačega zajetja. Prišli smo do precejšnjih nihanj rezultatov zaradi vremenskih sprememb (temperature in količine padavin).
Ugotovili smo, da voda ni v skladu s Pravilnikom o pitni vodi.
The project work deals with microbiological analysis of water taken from our home water reservoir. The purpose of the research was to find out the total number of microorganisms at 22 °C and 37 °C, the presence of coliform microorganisms, the presence of E. coli bacteria, enterococci bacteria and the presence of molds as well as to what extent the samples taken are
in accordance with the regulations. Water samples were taken from a kitchen faucet, where the
origin of water is water reservoir. We came to the considerable fluctuations in results because of the weather changes (temperature and rainfall). We have come to the conclusion that the water does not comply with the Drinking Water Regulations.
Vpliv sredstva za krepitev rastlin na kakovost in količino pridelka korenčka ( Daucus carota l)
Šola: Biotehniški center Naklo
Avtorice: Valerija Benedičič, Lucija Dolinar, Helena Mihevc
Mentorica: dr. Nataša Šink
V nalogi smo ugotavljali vpliv sredstev za krepitev rastlin Mineral na rast in razvoj rastlin ter na vsebnost sladkorja v korenih. Uporabili smo šest sredstev Mineral (Mineral zeleni, Mineral modri, Mineral rdeči, Mineral rumeni, Mineral rdeči forte in Mineral rumeni forte) v različnih kombinacijah. Kontrolno gojenje je bilo brez uporabe sredstev Mineral. Korenček smo sejali dvakrat (prva setev je bila izvedena aprila, druga pa maja), zato so bile razlike v povprečni temperaturi rasti. Ugotovili smo, da sredstva Mineral na rast rastlin vplivajo, vpliv pa je odvisen od kombinacije posameznih sredstev, časa setve rastline in klimatskih razmer. Od tega je odvisen tudi pridelek in vsebnost sladkorja v korenčku.
The aim of the study was to determine the effect of Mineral plant enhancers on plant growth and development as well as on the sugar content of the roots. We used six Mineral agents (Mineral green, Mineral blue, Mineral, Red, Mineral yellow, Mineral red forte and Mineral yellow forte) in different combinations. Control cultivation was without the use of Mineral substances. Carrots were sown twice (the first sowing was done in April and the second in May), so there were differences in the average growth temperature. We have found that Mineral agents effect the plant growth. The effect depends on the combination of individual agents, on the time of planting and on the climate conditions. The crop and sugar content of the carrots depends on it as well.
Socializacija otrok v vrtcu
Šola: Biotehniški center Naklo
Avtorica: Ema Primožič
Mentor: Andraž Kalamar
Namen raziskovalne naloge je bil ugotoviti, kakšen je vpliv vrtca na otrokovo socializacijo. Ob podrobnejši opredelitvi vseh treh stopenj socializacije teoretični del vključuje tudi glavno razlikovanje med vzgojo in socializacijo, pojasnjuje pojem predšolska vzgoja in prikazuje razvoj le-te na Slovenskem. Ugotoviti sem želela tudi, kakšna je vloga staršev in vzgojiteljev pri enem od pomembnejših dejavnikov socializacije, tj. igri, kolikšen je pomen športnih dejavnosti v vrtcu in vpliv okolice, igre in vzgojiteljev na otrokovo socializacijo. V raziskovalnem delu je uporabljena metoda intervjuja in anketiranja. Intervjuvala sem diplomirani vzgojiteljici iz zasebnega in javnega vrtca, Nežo Črljenec in Niko Arnolj, ankete pa so izpolnjevali starši, ki imajo otroke v vrtcu Agata v Poljanah. Ugotoviti sem želela, ali je otrok v vrtcu vedno več; je po mnenju staršev najboljši dejavnik socializacije v vrtcu igra; ali se otroci, ki so bili v vrtcu, lažje in hitreje socializirajo kot tisti, ki v vrtec niso bili vključeni; ali starši pri otrokovem razvoju v ospredje postavljajo disciplino in kolikšno vlogo pripisujejo vzgojiteljevi prilagodljivosti, komunikativnosti in strogosti.
The aim of the research paper is to find out how kindergarten influences the socialization of children. Theoretical part includes more detailed definition of all three stages of socialization as well as the main difference between education and socialization. Additionally, it explains the term of preschool education and shows development of preschool education in Slovenia. I also wanted to figure out what the role of parents and preschool teachers at one of the most important factors of socialization – play is, what importance sports activities have in kindergarten and how parents, preschool teachers and the environment influence the child socialization. In the research part of the paper I used the methods of interview and questionnaire. I interviewed the preschool teachers Neža Črljenec from private kindergarten and Nika Arnolj from public kindergarten. I carried out the questionnaire among the parents of children who attend kindergarten Agata in Poljane. My aim was to figure out whether the number of children in kindergartens is increasing, whether according to parents the best factor in socializing at kindergarten is play, whether the children who have been attending kindergarten socialize faster and easier than those who have not attended kindergarten, whether parents put the discipline in the first place at child’s development and how important the preschool teacher’s adaptability, strictness and communicativeness are for them.
Glasba na Slovenskem
Šola: Biotehniški center Naklo
Avtor: Matic Leskovec
Mentor: Andraž Kalamar
Kaj je tisto, kar vsako družbo ohranja, jo neguje, razvija in dela posebno? Vsi najprej pomislimo na jezik in kulturo, med katero spada tudi glasba.
Ker se mi zdi, da velikokrat pozabimo na svojo avtohtono glasbo, sem v tej nalogi raziskal razvoj slovenske glasbe – od takrat, ko na naših tleh še ni bilo Slovencev in do danes. V vsakem obdobju je bilo moje vprašanje tudi, kako je takratna glasba vplivala na razvoj človeka, njegove osebnosti in socializacije.
Slovenska glasba je namreč sestavni del zahodnoevropske glasbene kulture in je tesno povezana s sosednjimi državami, torej lahko rečem, da je naša glasba nekakšna mešanica glasbe sosednjih držav s svojimi značilnostmi.
Prek ankete sem ugotavljal, kako, predvsem mladi, poznamo slovensko glasbo in kaj pomeni za narodov in osebni razvoj. Z opravljenima intervjujema pa sem izvedel, kako poklicni glasbeniki razmišljajo o naši narodni glasbi.
Proizvodnja električne energije z uporabo biokulture
Šola: Biotehniški center Naklo
Avtorja: Lucija Dolžan, Matej Zupan
Mentor: Jure Ausec
V literaturi najdemo številne zapise o možnosti izkoriščanja biokultur za pridobivanje električne energije. Med mnogimi opisi poskusov, ki sva jih preizkusila tudi sama, sva opazila kar nekaj možnosti za izboljšave, zato sva se odločila analizirati delovanje pri različnih parametrih in jih čim bolj optimizirati.
Analizirala sva tako mikrobiološke dejavnike kot tudi fizikalne, ki vplivajo na delovanje izbrane biokulture in proizvodnjo električne energije. Spopadala sva se z mnogimi vprašanji, na katera sva si pomagala odgovoriti s številnimi eksperimenti. Odkrila sva optimalne parametre in jih uporabila za proizvodnjo električne energije, s katero sva uspela pognati elektronske komponente. Na koncu sva preračunala še finančno plat poskusa ter zapisala zaključke.
In literature many articles about the various uses of microbiological culture for generating electricity are available. Among many descriptions of the experiments that we tested ourselves, we discovered some opportunities for improvements. Therefore we decided to analyse how a microbiological culture works, using different parameters and optimizing them.
We analysed microbiological and physical parameters which affect our chosen biological culture and production of electricity. We were faced with many unanswered questions and only the many experiments we conducted brought us answers to those question. We figured out the optimal parameters and used them in experiments to produce electricity for powering electrical components. In the end, we calculated finances that would be needed for the experiments in commercial use and wrote down our conclusions.