Effects of natural plant tenderizers on proteolysis and texture of dry sausages produced with wild boar meat addition

This study was conducted to develop a method for improving tenderness and overall qualities of tough wild boar meat used to dry sausage  production with direct addition of raw pineapple (Ananas comosus), mango (Mangifera indica), kiwifruit - fuzzy kiwi (Actinidia deliciosa), or ginger (Zingiber officinale roscoe - ginger rhizome) juices contained a plant proteolytic enzyme. Dry-sausages were subjected to various chemical, mechanical and sensory evaluations. An increase in proteolysis was observed in all enzyme-treated samples compared to the control and as a consequence an improvement in juiciness, tenderness and overall acceptability scores were observed. Ginger or kiwifruit juice-treated sausages received better scores for texture, flavor, and overall acceptability. From these results, it is shown that those enzymes as a raw plant juices could be used as tenderizers in dry sausage production.Keywords: Dry sausages, wild boar meat, plant enzymes, proteolysis, texture, sensory properties.African Journal of Biotechnology Vol. 12(38), pp. 5670-567

Assessment of water quality in the Wiśniówka River considering circulation of organic matter

Variation of hydrochemical conditions, with special reference to adequacy of waters as fish habitats, was traced based on selected hydrochemical parameters obtained during the studies conducted from February 2013 till February 2014 year. The results were compared with earlier studies. The sources of organic pollution were identified, and the effects of biogenic substances on the biomass, as well as the self-purification capability of the river, were assessed. The total suspension exceeded the requirements for waters which are habitats of both salmonid and cyprinid fishes. Compared to the previous years, the load of organic and inorganic matter in the waters of Wiśniówka River increased; this may have resulted from external inflow, neighbourhood of the hatchery but also, to a small extent, from internal supply. The high availability of nitrogen-(NNH_4+; N-NO_2-, N-NO_3-) and phosphorus-(total phosphorus; P-PO_4 ^3-) based biogenic (substances favoured the biomass production, thus contributing to the increase in organic matter load in the river

Lichen response to ammonia deposition defines the footprint of a penguin rookery

Ammonia volatilized from penguin rookeries is a major nitrogen source in Antarctic coastal terrestrial ecosystems. However, the spatial extent of ammonia dispersion from rookeries and its impacts have not been quantified previously. We measured ammonia concentration in air and lichen ecophysiological response variables proximate to an Adèlie penguin rookery at Cape Hallett, northern Victoria Land. Ammonia emitted from the rookery was 15N-enriched (δ15N value +6.9) and concentrations in air ranged from 36–75 µg m−3 at the rookery centre to 0.05 µg m−3 at a distance of 15.3 km. δ15N values and rates of phosphomonoesterase (PME) activity in the lichens Usnea sphacelata and Umbilicaria decussata were strongly negatively related to distance from the rookery and PME activity was positively related to thallus N:P mass ratio. In contrast, the lichen Xanthomendoza borealis, which is largely restricted to within an area 0.5 km from the rookery perimeter, had high N, P and 15N concentrations but low PME activity suggesting that nutrient scavenging capacity is suppressed in highly eutrophicated sites. An ammonia dispersion model indicates that ammonia concentrations sufficient to significantly elevate PME activity and δ15N values (≥0.1 µg NH3 m−3) occurred over c. 40–300 km2 surrounding the rookery suggesting that penguin rookeries potentially can generate large spatial impact zones. In a general linear model NH3 concentration and lichen species identity were found to account for 72 % of variation in the putative proportion of lichen thallus N originating from penguin derived NH3. The results provide evidence of large scale impact of N transfer from a marine to an N-limited terrestrial ecosystem

Species and sex-specific variation in the antioxidant status of tench, Tinca tinca; wels catfish, Silurus glanis; and sterlet, Acipenser ruthenus (Actinopterygii) reared in cage culture

Background. Oxidative stress poses a serious threat to farmed fish, exemplified by depressed growth, decreased disease resistance, and reduced flesh quality. Therefore, the aim of this study was to examine differences in activity of antioxidant enzymes and concentration of selected biochemical parameters between blood plasma of both sexes of three species important for sustainable development of aquaculture: tench, Tinca tinca (Linnaeus, 1758); wels catfish, Silurus glanis Linnaeus, 1758; and sterlet, Acipenser ruthenus Linnaeus, 1758. Materials and methods. Experimental fishes were fed ad libitum for 60 days with a formulated diet (45% proteins, 20% fat, 16% carbohydrates, 8% ash and 2% fibre). At the end of the study venous blood samples were collected and 11 biochemical parameters were assessed: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), total antioxidant capacity (FRAP), alanine transaminase (ALT), aspartate transaminase (AST), lactate dehydrogenase (LDH), bilirubin, albumin, and uric acid. Results. Comparison between species revealed that the most significant differences were observed for tench and sterlet (in FRAP, GPx, CAT, GST LDH, ALT, bilirubin, and uric acid), less significant—for sterlet and wels (in FRAP, GST, LDH, AST, bilirubin, uric acid), followed by tench and wels catfish (in FRAP, GPx, GST, AST, and uric acid). Moreover, significant variations in the level of biochemical markers were also detected between sexes within each species, where the highest number was observed for tench (in FRAP, GPx, albumin, and uric acid), next wells catfish (in SOD, albumin, and bilirubin), and the lowest in sterlet (in ALA). Additionally, numerous differences in antioxidant potential (FRAP), antioxidant defence indices, as well as in markers of liver function, heart dysfunction, and markers of nutritional status were observed as species-specific and sex-specific. Conclusion. Results obtained in this study for the first time demonstrated species- and sex-related differences in plasma activity of antioxidant enzymes and concentration of selected biochemical parameters between tench, wels catfish, and sterlet reared in cage culture. The presented findings provide significant contribution not only to the existing knowledge of fish physiology but will also help to design optimal feeding practices to achieve sustainable cage aquaculture

Changes in abiotic conditions of a small river considering the effect of discharge from fish ponds

Ocena zmian warunków abiotycznych cieku z uwzględnieniem wpływu wód zrzutowych ze stawów karpiowych została wykonana w ciągu 6 miesięcy na górnym odcinku rzeki Młynówki. Wybrane wskaźniki hydrochemiczne wody, pobranej w czterech stanowiskach kontrolnych, oznaczano zgodnie z metodykami APHA. Wody cieku charakteryzowały się typową dla niewielkich rzek północnej Polski zmiennością termiki wody wraz z ich biegiem, lekko zasadowym odczynem (pH = 7,5– 7,7) dobrym natlenieniem – stężenie tlenu rozpuszczonego w wodzie (ang. DO – dissolved oxygen) zawierało się w przedziale 7,4–9,1 mg O2∙dm–3, a natlenienie 67,6–76,7% O2, z wyjątkiem miesięcy zimowych. Zawartość materii organicznej (BZT5, ChZTCr, chlorofil a) charakteryzowała się dużą zmiennością i sezonowością z biegiem rzeki. Dla BZT5 wartości zawierały się w przedziale 3,8–9,5 mg O2∙dm–3, dla ChZTCr 8,4–73,9 mg O2∙dm–3, a dla chlorofilu a w przedziale 3,7–94,1 mg·m–3. Badany odcinek rzeki należy uznać za zasobny w pierwiastki biogeniczne. Średnie stężenie azotu nieorganicznego wynosiło 2,166 mg N∙dm–3, a fosforu reagującego 0,078 mg P∙dm–3, wartości te były odpowiednio 18 i 7,8 razy większe od koncentracji notowanych w wodach niepoddanych antropopresji. Wykazano podwyższone, niespełniające wymogów dla ryb karpiowatych wartości BZT5, zawiesiny ogólnej (ang. TSS – total suspended solids), N-NO2 – i fosforu całkowitego (ang. TP – total phosphorus). Na jakość wody w rzece Młynówce istotny wpływ, oprócz naturalnych czynników hydrologicznych i zlewniowych, mogą mieć wprowadzane wody poprodukcyjne ze stawów karpiowych.Changes in abiotic conditions, considering the effect of water discharged from carp ponds were assessed in the upper section of the Młynówka River (within 6 months). The analyses of hydrochemical indicators were conducted according to methodology recommended by APHA. The river’s water was characterised by a variation in temperature with the distance from the source, which is typical of rivers of northern Poland, slightly alkaline reaction (pH = 7.5–7.7), good oxygenation (DO – dissolved oxygen concentration within 7.4–9.1 mg O2∙dm–3, oxygenation 67.6–76.7% O2) except for winter months. Organic matter content (BOD5, CODCr, chlorophyll a) was characterised by a large seasonal variation and varied with the river course. For BOD5 the values were within 3.8–9.5 mg O2 dm–3, for CODCr within 8.4–73.9 mg O2∙dm–3 and for chlorophyll a within 3.7–94.1 mg∙m–3. The studied river section should be regarded as rich in biogenic substances. The mean concentration of inorganic nitrogen was 2.166 mg N∙dm–3 and the reactive phosphorus 0.078 mg P∙dm–3, the values were respectively 18 and 7.8 times higher than those recorded for waters not subject to anthropopressure. The values of BOD5, TSS (total suspended solids), N-NO2 – and TP (total phosphorus) were increased, not meeting the requirements for cyprinid fishes. Besides the natural hydrological and catchment area features, the water quality in the Młynówka River was significantly affected by the discharge of water from the carp ponds

Zastosowanie membran ceramicznych do oczyszczania wód poprodukcyjnych z hodowli ryb w obiegach zamkniętych

The aim of the study was to analyze and assess the possibility of using a two-stage filtration system with ceramic membranes: a 3-tube module with 1.0 kDa cut-off (1st stage) and a one-tube module with 0.45 kDa cut-off (2nd stage) for treating effluent water from a juvenile African catfish aquaculture. The study revealed that during the 1st filtration stage of the effluent water, the highest degrees of retention were obtained with respect to: suspended solids SS (rejection coefficient RI=100%), turbidity (RI=99.40%), total iron (RI=89.20%), BOD5 (RI=76.0%), nitrite nitrogen (RI=62.30%), and CODCr (RI=41.74%). The 2nd filtration stage resulted in a lower reduction degree of the tested indicators in comparison to the 1st filtration stage. At the 2nd stage, the highest values of the rejection coefficient were noted in for the total iron content (RIV=100%), CODCr (RIV=59.52%; RV=64.28%, RVI=63.49%) and turbidity (RIV and RV = 45.0%, RVI=50.0%). The obtained results indicate that ceramic membranes (with 1.0 and 0.45 kDa cut-offs) may be used in recirculation aquaculture systems as one of the stages of effluent water treatment.Celem pracy była analiza i ocena możliwości wykorzystania dwustopniowego systemu filtrowania z zastosowaniem membran ceramicznych w postaci modułu 3 rurowego o granicznej rozdzielczości membrany (z ang. cut-off) wynoszącej 1.0 kDa (I stopień) i modułu jednorurowego o granicznej rozdzielczości membrany wynoszącej 0.45 kDa (II stopień), do procesu oczyszczania wód poprodukcyjnych pochodzących z hodowli narybku suma afrykańskiego. Podczas I stopnia procesu filtracji wody poprodukcyjnej badania wykazały, że w najwyższym stopniu zatrzymywane były: zawiesina ogólna SS – RI= 100,0%, mętność RI=99.40%, zawartość żelaza ogólnego RI=89.20%, BZT5 RI=76.0%, oraz azot azotynowy RI=62.30% i ChZTCr RI=41.74%. II stopień procesu filtracji powodował mniejszy stopień redukcji wartości badanych wskaźników niż I stopień procesu filtracji. Wówczas najwyższy współczynnik retencji odnotowano w przypadku zawartości żelaza ogólnego RIV=100%, CODCr RIV=59.52%; RV=64.28%, RVI=63.49% i mętności RIV i RV= 45.0%, RVI=50.0%. Uzyskane wyniki wskazują na możliwość wykorzystania membran ceramicznych (o cut-off 1.0 i 0.45 kDa) w recyrkulacyjnych systemach akwakultury, jako jeden z etapów oczyszczania wód poprodukcyjnych

Wpływ zrzutu wód poprodukcyjnych ze stawów pstrągowych na jakość wody w rzece Gowienicy

Fish farming and especially rearing and breeding of rainbow trout and carp is one of potential sources of surface water pollution. The study was aimed at assessing the effect of a rainbow trout farm on water quality in the Gowienica River in winter. Temperature, pH, electrolytic conductivity, total suspended solids, dissolved oxygen, BOD5, CODCr, alkalinity, water hardness, calcium, magnesium, ammonium-nitrogen, nitrate-nitrogen (III and V) and total phosphorus were determined according to Polish Norms and APHA [1995] in water samples collected in winter up- and downstream the study object. The increment of pollutant concentrations in rainbow trout farm effluents was referred to the requirements in Rozporządzenie MŚ [2006]. Performed studies and literature review show that effluents from the assessed fish farm did not worsen water quality of the river. Increased concentrations of total suspended solids and CODCr in effluents were noted only in March. According to data from the report on environmental status in zachodniopomorskie province in the years 2008–2011, poor water quality of the Gowienica River is recorded already upstream the rainbow trout farm. Pollution of this stretch of the river may originate from uncontrolled waste water management and from nutrient runoff from fields.Jednym z potencjalnych źródeł zanieczyszczenia wód powierzchniowych jest gospodarka rybacka zajmująca się głównie chowem i hodowlą pstrąga tęczowego i karpia. Celem pracy była ocena wpływu działalności gospodarstwa pstrągowego na jakość wód Gowienicy w sezonie zimowym. W okresie zimowym w pobranych próbkach wody w punktach powyżej i poniżej obiektu oznaczano następujące wskaźniki: temperaturę, pH, przewodność elektrolityczną, zawiesinę ogólną, tlen rozpuszczony w wodzie, BZT5, ChZTCr, zasadowość, twardość, wapń, magnez, azot amonowy, azot azotanowy (III) i (V), fosfor ogólny – zgodnie z wybranymi Polskimi Normami i zaleceniami APHA [1995]. Określano przyrost zanieczyszczeń w wodach poprodukcyjnych z hodowli pstrągów, który odnoszono do wymogów zawartych w Rozporządzeniu MŚ [2006]. Jak wynika z przeprowadzonych badań oraz z przeglądu literatury, wody poprodukcyjne pochodzące z działalności ocenianego gospodarstwa rybackiego nie wpływały na pogorszenie jakości wody badanej rzeki. Uzyskane w pracy wyniki wykazały przyrost stężenia zawiesin ogólnych i ChZTCr, w wodach poprodukcyjnych tylko w marcu. Zgodnie z danymi zawartymi w raportach o stanie środowiska w woj. zachodniopomorskim w latach 2008–2011, niezadowalająca jakość wód Gowienicy jest notowana już na odcinku powyżej gospodarstwa pstrągowego. Źródłem zanieczyszczeń występujących na tym odcinku Gowienicy może być nieuregulowana gospodarka kanalizacyjna w gminie, jak również spływy składników biogennych z pól

Investigation of the effectiveness of the cleaning flume system applied on the Młynówka River (Lubusz voivodeship)

Przeprowadzono roczną ocenę funkcjonowania systemu filtrów wypełnionych kształtkami z polipropylenu i keramzytem, usytuowanych w korycie rzeki, których zadaniem była redukcja zawiesin ogólnych oraz biogenów w wodzie przed jej odprowadzeniem do śródmiejskiego jeziora. Wykazano, że z powodu złej konserwacji i małej ilości zabiegów czyszczących, skuteczność systemu znacznie spadła w stosunku do okresu prawidłowej eksploatacji. Dotyczyło to przede wszystkim wyczerpania możliwości zatrzymywania głównego pierwiastka biogennego – fosforu. W okresie monitorowania obiekt utrzymał zdolność do redukcji zanieczyszczeń organicznych, zawiesin i azotu.An annual assessment pertaining to the functioning of the filter systems filled with polypropylene and gravelite profiles, located in the river bed, to reduce total suspensions and biogenic compounds in the water before it was directed to the city lake, was carried out. It has been shown that due to poor maintenance and a small number of cleaning operations, the efficiency of the system has decreased considerably, comparing to the period of correct operation. This was mainly related to the exhaustion of the ability to retain the main biogenic element – phosphorus. Througout the monitoring period, the facility retained the ability to reduce organic pollutants, suspended solids and nitrogen

Selected elements in surface waters of Antarctica and their relations with the natural environment

The aim of the study was to specify the concentration of selected chemical elements in surface waters of King George Island, off the western coast of the Antarctic Peninsula. The research encompassed six streams, a lake and an artificial water reservoir located on the western coast of Admiralty Bay. Measured hydrochemical parameters included pH, conductivity, total dissolved solids (TDS), and total and dissolved forms elements such as Al, Co, Ni, Cu, Zn, Cd, Pb, Mn, Fe, As and Se. The values of pH, conductivity and TDS had the following ranges: 6.09–8.21, 6.0–875 µS cm−1 and 7.0–975 mg/L, respectively, and were typical for surface waters of Antarctica. Wide disparities were discovered regarding concentrations of the investigated elements, ranging from <0.01 µg/L for Cd to 510 µg/L for Fe, and differing from one water body to another. The investigated elements are discussed with reference to environmental conditions and anthropogenic factors. Concentrations of total and dissolved forms of elements are considered in connection with the composition of soil in their surroundings and with atmospheric deposition, mostly such as that took place locally. The increased levels of Pb and Zn concentrations in the immediate proximity of a research station suggested anthropogenic contamination