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Influence of artificial light at night on communities of sessile invertebrates on hard substratum
No full textDo sada je poznat utjecaj umjetnog svjetla noću na pojedine vrste morskih organizama, no
utjecaj na razini njihovih zajednica vrlo je slabo istražen. Utvrđivanje ovih promjena, posebno
na razini zajednica sesilnih beskralježnjaka presudno je za razumijevanje temeljnih fizioloških
mehanizama i donošenje efikasnih mjera u gospodarenju obalnim prostorom. Stoga je cilj ovog
istraživanja bio utvrditi promjene u sastavu, bioraznolikosti i biomasi zajednica sesilnih
beskralježnjaka na tvrdoj podlozi uzrokovanih umjetnim žutim svjetlom noću kroz tri mjeseca.
Uzorkovanje je obavljano jednom mjesečno. Utvrđene su statistički značajne razlike u sastavu
zajednica pri prva dva uzorkovanja. Indeks bogatstva vrsta i Shannon indeks su bili statistički
značajno veći u zajednicama izloženim umjetnom svjetlu noću. Mokra biomasa je pri prvom
uzorkovanju bila statistički značajno veća u zajednicama koje nisu bile izložene umjetnom
svjetlu noću pri prvom uzorkovanju, dok se pri drugom i trećem nije značajno razlikovala. Suha
masa je bila statistički značajno veća u zajednicama izloženim umjetnom svjetlu noću. Ako se
rezultati ovog istraživanja usporede s rezultatima istraživanja provedenog istovremeno na istom
lokalitetu, ali s korištenim bijelim LED svjetlom, može se zaključiti da je bijela LED svjetlost imala
štetniji utjecaj na bioraznolikost promatranih zajednica.The influence of artificial light at night (ALAN) is investigated for single species, but it has been
poorly researched on community level. The determination of these changes, especially in
communities of sessile invertebrates, is crucial for understanding the underlying mechanisms
and efficient coastal area management. Therefore, the aim of this research was to determine
the changes in composition, biodiversity and biomass in communities of sessile invertebrates
on hard substratum caused by exposure to ALAN for three months. The communities were
sampled monthly. Statistically significant differences in community composition were recorded
in the first and second sampling. Species richness and Shannon index were significantly higher
in communities exposed to ALAN. Wet biomass was significantly bigger in the first sampling in
communities that were not exposed to ALAN and in the second and third sampling, no
statistically significant differences were found. Dry biomass was significantly bigger in
communities exposed to ALAN. If the results of this research are compared to results of a
research that was done at the same time and place with the same methodology, but white LED
light was used instead of yellow, it can be concluded that white light had a more negative effect
on biodiversity
Clostridium tyrobutyricum in milk and late blowing of cheese
No full textKasno nadimanje sira je česta mana tvrdih sireva u mljekarskoj industriji. Ovu manu
sira možemo prepoznati po šupljinama, atipičnim rupicama i po većem broju otvora koji su
razasuti u sirnome tijestu. Osim toga, možemo ga prepoznati i po žilavome sirnome tijestu,
bljutavome okusu i neugodnom mirisu. Još jedna od opasnosti kod sireva sa kasnim
nadimanjem je često površinsko pucanje kroz čije se pukotine otvara put drugim štetnim
bakterijama i plijesnima, u unutrašnjost sira, čime se kvarenje još više pojačava i ubrzava.
Glavni uzročnik kasnog nadimanja sira je gram pozitivna bakterija Clostridium tyrobutyricum
koja najčešće dolazi iz tla ili silaže. Ona provodi maslačno-kiselu fermentaciju, gdje iz laktata
nastaju maslačna kiselina, ugljikov dioksid i vodik. Time dolazi do stvaranja plina koji uzrokuje
stvaranje rupica i pukotina u sirnome tijestu. Osim bakterije C. tyrobutyricum, kasno
nadimanje sira mogu uzrokovati i ostale Clostridium vrste: C. butyricum, C. beijerinckii i C.
sporogenes. One spadaju u termorezistentnu skupinu bakterija koje preživljavaju standardnu
temperaturu pasterizacije (63 °C). Stoga se tijekom procesa proizvodnje sira dodaje enzim
lizozim radi prevencije pogreške nadimanja. Lizozim se proizvodi iz bjelanjka jajeta, može
uzrokovati alergijske reakcije pa ga pri deklariranju na listi sastojaka sira potrebno istaknuti
masnim slovima.Late blowing of cheese is a cheese fault of hard cheeses that frequently occurs in the
dairy industry. This defect can be identified by cavities, atypical holes, and an increased
number of openings scattered throughout the cheese mass. Additionally, it can be recognized
by a tough cheese texture, bland taste, and unpleasant odor. Another danger with late
blooming cheeses is that they often develop surface cracks, which provide pathways for other
harmful bacteria and moulds to penetrate into the interior of the cheese, thereby intensifying
and accelerating spoilage. The primary cause of late blowing in cheese is the gram-positive
bacterium Clostridium tyrobutyricum, which usually originates from soil or silage. This
bacterium produces butyric acid, carbon dioxide, and hydrogen from lactate. This results in
gas formation, causing holes and cracks in the cheese mass. Besides C. tyrobutyricum, other
Clostridium species such as C. butyricum, C. beijerinckii, and C. sporogenes can also cause late
blowing of cheese. These bacteria belong to the thermoresistant group, surviving the usual
pasteurization temperatures. Therefore, during cheese production, the enzyme lysozyme is
added to prevent this defect. Lysozyme is produced from egg white, so it needs to be
highlighted in bold letters in the list of cheese ingredients, as it can cause allergic reactions
Product positioning using the multidimensional scaling method on the example of artisanal bread
No full textAnketno ispitivanje provedeno je na uzorku od 100 potrošača kruha na zagrebačkom tržištu. Za utvrđivanje tržišne pozicije zanatskog kruha korištena je metoda multidimenzionalnog skaliranja. Zanatski kruh brenda Bread Club, uključen u istraživanje, zauzima jasno različitu tržišnu poziciju u odnosu na industrijske brendove kruha (Dubravica, Mlinar, Pan-pek). Kako bi se utvrdile razlike između kruhova, dodatno je provedeno ocjenjivanje njihovih organoleptičkih obilježja, koja su uključivala okus, miris, prozračnost teksture te hrskavost korice. Ispitanici različito percipiraju organoleptička svojstva zanatskog i industrijskog kruha, pri čemu zanatski kruh ima bolji imidž. Rezultati istraživanja daju vrijedne informacije proizvođačima zanatskog kruha za izradu marketinških strategija.A survey was conducted on a sample of 100 bread consumers in the Zagreb market. A significant number of respondents were unaware of the difference between industrial and artisanal bread. The method of multidimensional scaling was used to determine the market position of artisanal bread. The artisanal bread from the Bread Club brand, included in the study, occupies a clearly defined market position in relation to industrial bread brands (Dubravica, Mlinar, Pan-pek, Mlinar). To identify the differences between the breads, an additional sensory evaluation was conducted, assessing attributes such as taste, aroma, texture airiness, and crust crispiness. Respondents perceive the organoleptic properties of artisanal and industrial bread differently, with the artisanal type having a better image. The research results provide valuable information for artisanal bread producers in developing marketing strategies
The effect of nitrogen and boron fertilization on the phenolic profile of olive (Olea europaea L.) vegetative organs and its antifungal effect on Verticillium dahliae Kleb.
No full textMaslina je voćna vrsta prirodno raširena na području Mediterana, a na području Republike Hrvatske zastupljen je i opisan značajan broj sorata ove gospodarski značajne kulture. Pravilna gnojidba masline neophodna je u proizvodnji visoko kvalitetnih maslinovih ulja. Gnojidba dušikom (N) i borom (B) može imati pozitivan ili negativan utjecaj na maslinu i okoliš. Navedeni makro- i mikroelementi mogu različito utjecati na razvoj masline i metaboličke promijene na njezinim vegetativnim organima. Nadalje, gnojidba N i B može utjecati na tolerantnost masline prema različitim štetnim organizmima. Fenolni spojevi sudjeluju u obrambenom odgovoru masline, a mogu značajno doprinijeti tolerantnosti na verticilijsko venuće masline (Verticillium dahliae Kleb). Stoga, cilj ovog rada bio je utvrditi utjecaj primjene različitih molarnih koncentracija N i B na koncentraciju fenolnih spojeva (mg/100 g ST) u vegetativnim organima (korijen, izbojak, list) masline kako bi se ispitao učinak ekstrakata fenola na izolat V. dahliae V-263 u uvjetima in vitro. Kako bi se utvrdio utjecaj gnojidbe N i B na rast i razvoj masline, utvrđena su vegetativna svojstva izbojka (duljina izbojka, broj internodija, broj listova) i korijena (duljina, volumen, površina i promjer korijena) masline. S ciljem određivanja koncentracije N (g/kg ST) i B (mg/kg ST) te koncentracije fenola (mg/100 g ST) masline analizirani su uzorci korijena, izbojka i lista. Nadalje, protugljivični učinak ekstrakata fenola masline (korijen, izbojak, list), prethodno modificiranih primjenom gnojidbenih tretmana s N ili B, istražen je u uvjetima in vitro. Primjena gnojidbenih tretmana značajno je utjecala na vegetativna svojstva masline. Primjena viših molarnih koncentracija N i B pozitivno je utjecala na njihovo usvajanje korijenom te daljnju translokaciju u ostale vegetativne organe masline. Primjena gnojidbenih tretmana s N i B različito je utjecala na koncentraciju pojedinačnih fenolnih spojeva (mg/100 g ST), utvrđenih u vegetativnim organima masline. Ekstrakti fenola vegetativnih organa masline imali su različit inhibitorni učinak na klijavost konidija, porast i morfološka obilježja micelija V. dahliae V-263 u uvjetima in vitro.Olive (Olea europaea L.) has great cultural and economic importance in the Mediterranean basin. Olive oil production is an important source of revenue for many countries in the region and contributes to the growth of their economies. The production of olives and olive oil depends on numerous factors, including the correct application of nutrients. When it comes to olive production and the environment, the type of fertilization used can make a significant difference. Nitrogen (N) and boron (B) fertilization, in particular, can have varying effects on olive production.
Fertilization can greatly impact olive growth, nutrient uptake and distribution, phenolic content in olive, and olive tolerance to phytopathogenic fungus Verticillium dahliae Kleb. This study aimed to investigate the effects of N and B fertilization on their content in various parts of olive, including the roots, stem, and leaves. Additionally, this study aimed to evaluate the impact of these nutrients on olive growth traits. This study also examined the effect of N and B fertilization on the phenolic content (root, stem, leaves) and the antifungal activity of phenolic extracts on V. dahliae V-263.
Fertilization experiments were conducted separately for N (experiment 1) and B (experiment 2). Seven different treatments were adopted in each experiment, representing seven molar concentrations of either N or B. The control treatments were N0 and B0. The study was conducted on one-year-old plantlets of the Istarska bjelica cultivar, which were grown in an inert substrate under controlled conditions. Measurements were taken periodically, including air temperature, substrate moisture, substrate pH, and olive growth traits. At the end of the experiment, samples of roots, stems, and leaves were collected and prepared for further analysis. The growth traits of olive roots were analyzed at the end of the experiment. Chemical analyses were conducted to evaluate the content of N (g/kg dry weight (DW)) or B (mg/kg DW), total and individual phenolic compounds (mg/100 g DW) in roots, stems, and leaves. In vitro antifungal activity of phenolic extracts, obtained from fertilization treatments with N or B, was assessed against V. dahliae V-263 (experiment 3 a,b; experiment 4).
The growth traits of olive were positively affected by the applied N fertilization treatments (N1 – N6), resulting in a greater root and shoot growth compared to the growth resulting from control treatment N0. The uptake and translocation of N from roots to stem and leaves were significantly affected by the application of different N fertilization treatments (N0 – N6).
The lowest content of N (g/kg DW) in olive (root, stem, leaves) was found in the control fertilization treatment N0. The content of total and individual phenolic compounds was negatively affected by the applied fertilization treatments (N4 – N6). This study reports the antifungal activity of phenolic extracts (EF), EF-N0 – EF-N6, (root, stem, leaves) modified by N fertilization treatments (N0 – N6). The application of phenolic extracts (treatments EF-N0 – EF-N6) on V. dahliae V-263 had no inhibitory effect on the conidial germination, therefore showing lack of antifungal activity.
The application of higher molar concentrations of B (fertilization treatments B3 – B6) positively affected olive growth traits when compared to the control fertilization treatment B0. The lowest content of B (mg/kg DW) was observed in the control fertilization treatment B0 of all investigated parts of olive. The applied fertilization treatments B1 – B6 had varying effects on the content of total and individual phenolic compounds (mg/100 g DW) in the different parts of olive. The results of this study demonstrated that the phenolic extracts of roots and leaves had a significant antifungal effect on V. dahliae V-263. Specifically, phenolic extracts of roots (treatments EF-B0, EF-B3, and EF-B4), as well as phenolic extracts of stems (treatment EF-B2), significantly inhibited the conidial germination of V. dahliae V-263 therefore exhibiting antifungal effect. Additionally, significant inhibitory and antifungal effects were observed on the mycelium growth of V. dahliae V-263 when phenolic extracts from olive roots (treatments EF-B0 – EF-B6) and leaves (treatments EF-B0, EF-B2 – B5) were applied. The applied phenolic extracts (treatments EF-B0 – EF-B6) had different effects on the morphological characteristics of V. dahliae V-263 mycelium in vitro.
The findings of this study contribute to a better understanding of the complex interaction between nutrient fertilization, phenolic compounds, and the relation between modified phenolic extracts and V. dahliae V-263 conidial germination and mycelium growth. Further studies are required to identify the effect of N or B fertilization on the content of phenolic compounds in the olive tree and their role in olive tolerance to V. dahliae V-263
Plan upravljanja istraživačkim podacima na projektu IP-2019-04-3325
No full textNutritivna i funkcionalna vrijednost koprive (Urtica dioica L.) primjenom suvremenih hidroponskih tehnika uzgoj
Physicochemical and organoleptic properties of bierbrand (beer brandy)
No full textBierbrand ili eau de vie de biere je jako alkoholno piće dobiveno izravno
destilacijom svježeg piva, tako da destilat zadrži organoleptička svojstva piva. U
pregledu literature prikazan obrađeni su svi osnovni postupci u proizvodnji piva.
Objašnjen je proces destilacije, destilacijski postupci u proizvodnji jakih alkoholnih
pića te dvije osnovne vrste destilacijskog uređaja koje su najzastupljenije u
proizvodnji. Obrađeni su i postupci dozrijevanja destilata kao i kemijske promjene
koje se zbivaju u destilatu tijekom procesa dozrijevanja. U praktičnom dijelu rada
svježe pivo destilirano je na složenom destilacijskom uređaju s kolonom i
deflegmatorom čime je proizveden bierbrand. Provedena je i osnovna fizikalnokemijska
analiza pojedinih frakcija destilata čiji su rezultati također prikazani.Bierbrand or eau de vie de biere is a strong alcoholic beverage obtained
directly by distilling fresh beer, so the distillate retains the organoleptic properties of
the beer. The literature review covers all the basic procedures in beer production.
The distillation process is explained, including distillation procedures in the
production of strong alcoholic beverages, and the two main types of distillation
equipment most commonly used in production. The aging procedures of the distillate
and the chemical changes that occur in the distillate during the aging process are
also discussed. In the practical part of the work, fresh beer was distilled using a
complex distillation apparatus with a column and a dephlegmator, producing
bierbrand. A basic physicochemical analysis of individual distillate fractions was
conducted, and the results are also presented
Dioxins in meat : toxic compounds in our diet
No full textDioksini su skupina vrlo toksičnih kemijskih spojeva čija prisutnost u okolišu i prehrambenom lancu predstavlja ozbiljan rizik za javno zdravlje. Ovi spojevi nastaju kao nusproizvodi industrijskih procesa, poput spaljivanja otpada, proizvodnje pesticida i papira. Dioksini su vrlo stabilni spojevi, što znači da se teško razgrađuju i mogu se akumulirati u okolišu. Njihova pojava u mesu izaziva zabrinutost jer je dugotrajno izlaganje dioksinima povezano je s nizom zdravstvenih problema kao što su reproduktivni i razvojni poremećaji, oštećenje imunološkog sustava, ometanje rada hormona te kancerogenost. Najpoznatiji dioksin je 2,3,7,8-tetrahidrodioksin (TCDD), koji se smatra jednim od najtoksičnijih unutar ove skupine spojeva. Dioksini se akumuliraju u tlu i biljkama, ali najveća opasnost dolazi od kontaminirane hrane koja ulazi u prehrambeni lanac. Zbog biokoncentracije i lipofine prirode, glavni izvor izloženosti za ljude je hrana bogata mastima poput mesa, ribe i mliječnih proizvoda. Istraživanja pokazuju da koncentracije dioksina u mesu variraju ovisno o vrsti mesa i geografskom području, pri čemu meso iz određenih regija može imati značajno veće razine dioksina, što je posljedica lokalnih izvora zagađenja poput industrijskih emisija i zagađenja tla. Smanjenje izloženosti dioksinima zahtijeva suradnju regulatornih tijela, industrije i poljoprivrednika, uz primjenu čišćih tehnologija, sustavnog nadzora hrane te edukacije potrošača o sigurnim prehrambenim navikama radi zaštite javnog zdravlja.Dioxins are a group of highly toxic chemical compounds whose presence in the environment and the food chain poses a serious public health risk. These compounds are by-products of industrial processes such as waste incineration, pesticide production, and paper manufacturing. Dioxins are highly stable compounds, meaning they are resistant to degradation and can accumulate in the environment. Their occurrence in meat raises concerns because long-term exposure to dioxins is linked to various health problems, including reproductive and developmental disorders, immune system damage, hormonal disruptions, and cancer. The most well-known dioxin is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), considered one of the most toxic compounds within this group. Dioxins accumulate in soil and plants, but the greatest danger comes from contaminated food entering the food chain. Due to bioconcentration and their lipophilic nature, the main source of exposure for humans is fatty foods such as meat, fish, and dairy products. Research shows that dioxin levels in meat vary depending on the type of meat and geographic area, with meat from certain regions potentially containing significantly higher dioxin levels due to local pollution sources such as industrial emissions and soil contamination. Reducing exposure to dioxins requires cooperation among regulatory bodies, industry, and farmers, along with the implementation of cleaner technologies, systematic food monitoring, and educating consumers on safe dietary practices to protect public health
Smart gardens
No full textPametni vrtovi predstavljaju inovativno rješenje koje kombinira modernu tehnologiju s
hortikulturom kako bi se optimiziralo uzgoj biljaka u urbanim i ruralnim sredinama. Ovaj rad
istražuje koncept pametnih vrtova, njihove komponente, prednosti i izazove u implementaciji.
Pametni vrtovi koriste senzore, IoT (Internet of Things) uređaje i automatizirane sustave za
praćenje i upravljanje uvjetima uzgoja. Senzori prate parametre kao što su vlažnost tla,
temperatura, razina svjetlosti i kvaliteta zraka, pružajući korisnicima podatke za donošenje
informiranih odluka. Glavne prednosti pametnih vrtova uključuju smanjenje potrošnje vode,
povećanje prinosa, unapređenje kvalitete biljaka i smanjenje ljudskog napora. Nadalje, pametni
vrtovi mogu imati važnu ulogu u urbanom vrtlarstvu, omogućujući proizvodnju svježih
namirnica u gradskim sredinama i doprinoseći održivosti urbanih zajednica. Međutim,
implementacija pametnih vrtova suočava se s određenim izazovima, uključujući visoke početne
troškove, ograničen uzgojni prostor i potencijalne rizike povezane s IoT uređajima. Unatoč tim
izazovima, očekuje se da će napredak tehnologije i povećana svijest o održivosti potaknuti širu
primjenu pametnih vrtova u budućnosti.Smart gardens represent an innovative solution that combines modern technology with
horticulture to optimize plant cultivation in both urban and rural settings. This paper explores
the concept of smart gardens, their components, advantages, and challenges in implementation.
Smart gardens use sensors, IoT (Internet of Things) devices, and automated systems to monitor
and manage growing conditions. Sensors track parameters such as soil moisture, temperature,
light levels, and air quality, providing users with data to make informed decisions. The main
advantages of smart gardens include reduced water consumption, increased yields, improved
plant quality, and reduced human effort. Furthermore, smart gardens can play a significant role
in urban gardening, enabling the production of fresh produce in urban areas and contributing to
the sustainability of urban communities. However, the implementation of smart gardens faces
certain challenges, including high initial costs, limited growing space, and potential risks
associated with IoT devices. Despite these challenges, technological advancements and
increased awareness of sustainability are expected to drive the broader adoption of smart
gardens in the future
Cultivation possibilities of oyster mushrooms (Pleurotus spp.) on coffee grounds
No full textCilj ovog rada je prikazati mogućnosti uzgoja gljiva bukovača na talogu kave. Bukovača je gljiva koja se uzgaja u cijelom svijetu, a može se pronaći kao samonikla vrsta na prirodnim stanišnima. Značajna je po bogatom sadržaju bjelančevina, masnih kiselina, minerala i vitamina. Uzgoj bukovače je u stalnom porastu zbog jednostavnog načina uzgoja te mogućnosti korištenja raznih supstrata za uzgoj. Prvobitno se bukovača uzgajala na oblicama listopadnog drveća, dok se danas uz oblice koriste pripremljeni supstrati - slama žitarica (pšenična, zobena, ječmena slama), livadsko sijeno, kukuruzovina, ali i na talogu od kave. Uzgoj na talogu od kave je dobar ekološki način upotrebe taloga za uzgoj gljiva. Prednosti uzgoja gljive na talogu od svježe kave je supstrat koji je već pasteriziran kroz proces kuhanja kave. Pored toga, otpadni talog od kave proizvodi metan nakon raspadanja što dovodi do povećanja razine metana na odlagalištima, a zatim u atmosferi. Kako bi se navedeno spriječilo, talog kave može se koristiti za proizvodnju gljiva, osiguravajući kompost za uzgoj bukovača, a što pozitivno djeluje na smanjenje emisije metana.The aim of this paper is to present the possibilities of growing oyster mushrooms on coffee grounds. The oyster mushroom is a globally cultivated mushroom that also occurs as a wild form in natural habitats. It is characterized by its high content of proteins, fatty acids, minerals and vitamins. The cultivation of oyster mushrooms is constantly increasing due to the simple cultivation methods and the possibility of using different substrates. Originally, oyster mushrooms were grown on the trunks of deciduous trees, but today prepared substrates such as cereal straw (wheat, oat, barley straw), meadow hay, corn stalks and even coffee grounds are also used. Growing mushrooms on coffee grounds is an environmentally friendly way of using the soil for mushroom cultivation. One advantage of growing mushrooms on fresh coffee grounds is that the substrate has already been pasteurized by the coffee brewing process. In addition, coffee grounds produce methane after decomposition, which contributes to increased methane levels in landfills and thus in the atmosphere. To prevent this, coffee grounds can be used for mushroom cultivation, creating compost for oyster mushroom cultivation, which has a positive effect on reducing methane emissions
Possibility of adaptation of fruit production to climate changes
No full textPosljednjih desetljeća sve su izraženije klimatske promjene koje imaju znatan utjecaj na poljoprivrednu proizvodnju općenito, pa tako i na voćarsku proizvodnju. Dosadašnjom tehnologijom proizvodnje i sortimentom ne postiže se zadovoljavajuća kvaliteta ni kvantiteta priroda. Cilj rada je na temelju literaturnih izvora utvrditi aktualne probleme u voćarskoj proizvodnji koji su posljedica pojave neuobičajenih vremenskih prilika te ukazati na mogućnost prilagodbe sortimenta i tehnologije uzgoja u cilju postizanja redovitih i viših priroda kao i bolje kakvoće plodova.In recent decades, climatic changes have become increasingly noticeable, with a significant impact on agricultural production in general, including fruit production. The current production technology and assortment do not achieve a satisfactory quality or quantity of yield. The aim of the paper is to identify, based on literature sources, the current problems in fruit production due to unusual weather conditions and to show the possibility of adapting the assortment and cultivation technology to achieve a consistent and higher yield and better fruit quality