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"Pinguins."
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The tragic tale of the great auk
\"For hundreds of thousands of years great auks thrived in the icy seas of the North Atlantic, bobbing on the waves, diving for fish, and struggling up onto rocky shores to mate and hatch their fluffy chicks. But by 1844, not a single one of these magnificent birds was alive ... Although undeniably tragic, the final demise of the Great Auk led to the birth of the conservation movement\"--Amazon.com.
Book
Guamara and Cocuixtle: Source of Proteases for the Transformation of Shrimp By-Products into Hydrolysates with Potential Application
Since the fruits of Bromelia pinguin and Bromelia karatas are rich in proteases, the aim of this research was to optimize the hydrolysis process of cooked white shrimp by-products due to the effect of these proteases. A robust Taguchi L16’ design was used to optimize the hydrolysis process. Similarly, the amino acid profile by GC-MS and antioxidant capacity (ABTS and FRAP) were determined. The optimal conditions for hydrolysis of cooked shrimp by-products were pH 8.0, 30 °C, 0.5 h, 1 g of substrate and 100 µg/mL of B. karatas, pH 7.5, 40 °C, 0.5 h, 0.5 g substrate and 100 µg/mL enzyme extract from B. pinguin and pH 7.0, 37 °C, 1 h, 1.5 g substrate and 100 µg/mL enzyme bromelain. The optimized hydrolyzates of B. karatas B. pinguin and bromelain had 8 essential amino acids in their composition. The evaluation of the antioxidant capacity of the hydrolyzates under optimal conditions showed more than 80% inhibition of in ABTS radical, B. karatas hydrolyzates had better higher ferric ion reduction capacity with 10.09 ± 0.02 mM TE/mL. Finally, the use of proteolytic extracts from B. pinguin and B. karatas to optimize hydrolysis process allowed obtaining hydrolyzates of cooked shrimp by-products with potential antioxidant capacity.
Journal Article
Isoelectric focusing, effect of reducing agents and inhibitors: partial characterization of proteases extracted from Bromelia karatas
The aim of this research is the partial characterization of proteases extracted from
B. karatas
; the isolation and purification of proteases from
B. karatas
fruits were achieved using precipitation, separation by size exclusion chromatography and anion-exchange chromatography; molecular mass (MM) was determined, and the effect of inhibitors, reducing agents and heat on enzyme activity was analyzed. These proteases were compared with proteases from
Bromelia pinguin
(
B. pinguin
) and evaluated under similar conditions. The isolation procedure was adequate; only a few protein bands are present in sodium dodecyl sulfate polyacrylamide gel electrophoresis. Furthermore, zymogram analysis showed protein bands with enzyme activity. Inhibitors, reducing agents and heat were unable to inactivate the proteases extracted from
B. karatas
and
B. pinguin
. The semi-purified extracts are a set of proteases with a MM of 66 kDa, but different isoelectric points (3.5–6.5 for
B
.
karatas
and 5–9 for
B
.
pinguin
), which are found in quaternary structures with proteolytic activity. When denatured, they segment into fragments of approximately 20 and 10 kDa. The data indicate that these plants could be used as sources of proteases since they present good proteolytic activity (21.93 U
T
for proteases from
B. karatas
and 43.58 U
T
for proteases from
B. pinguin
) and that
B. Karatas
has potential applications comparable to
B. pinguin
in the food and health industries.
Journal Article
Bromelia karatas and Bromelia pinguin: sources of plant proteases used for obtaining antioxidant hydrolysates from chicken and fish by-products
In the present study, we evaluated new sources of plant proteases from fruits of
Bromelia karatas
(BK) and
Bromelia pinguin
(BP) to obtain antioxidant hydrolyzates/bioactive peptides (BPs) derived from chicken by-products (CH) and fish by-products (FH). The profile of the peptides was identified by reverse-phase high-resolution liquid chromatography (RP-HPLC) and the size weight distribution by molecular exclusion chromatography (SEC). The hydrolysates obtained with BK in both sources of by-products showed greater antioxidant capacity compared to those obtained with BP, presenting similar or higher values when compared to a commercial plant enzyme. The use of new sources of plant proteases allowed to obtain hydrolysates of hydrophilic character with a high percentage (> 50%) of peptides with molecular weights < 17.5 kDa from chicken and fish by-products. Therefore, based on the results obtained in antioxidant capacity it is possible to consider the hydrolysates as potential ingredients, food additives, and pharmaceutical products.
Journal Article
Partial Characterization of the Proteolytic Properties of an Enzymatic Extract From “Aguama” Bromelia pinguin L. Fruit Grown in Mexico
Plant proteases are capable of performing several functions in biological systems, and their use is attractive for biotechnological process due to their interesting catalytic properties.
Bromelia pinguin
(aguama) is a wild abundant natural resource in several regions of Central America and the Caribbean Islands but is underutilized. Their fruits are rich in proteases with properties that are still unknown, but they represent an attractive source of enzymes for biotechnological applications. Thus, the proteolytic activity in enzymatic crude extracts (CEs) from wild
B. pinguin
fruits was partially characterized. Enzymes in CEs showed high proteolytic activity at acid (pH 2.0–4.0) and neutral alkaline (pH 7.0–9.0) conditions, indicating that different types of active proteases are present. Proteolytic activity inhibition by the use of specific protease inhibitors indicated that aspartic, cysteine, and serine proteases are the main types of proteases present in CEs. Activity at pH 3.0 was stable in a broad range of temperatures (25–50 °C) and retained its activity in the presence of surfactants (SDS, Tween-80), reducing agents (DTT, 2-mercapoethanol), and organic solvents (methanol, ethanol, acetone, 2-propanol), which suggests that
B. pinguin
proteases are potential candidates for their application in brewing, detergent, and pharmaceutical industries.
Journal Article
Antioxidant capacity of egg, milk and soy protein hydrolysates and biopeptides produced by Bromelia pinguin and Bromelia karatas-derived proteases
Given the lack of knowledge in the generation and biological activity of biopeptides (BP) produced by Bromelia pinguin and Bromelia karatas-derived proteases, the objective of this work was to evaluate the antioxidant capacity (AOX) of protein hydrolysates and peptide fractions from hydrolysis of egg, milk and soy proteins with enzymes extracted from Bromelia pinguin and Bromelia karatas fruits. The degree of hydrolysis (DH) of the mentioned proteins was measured. The hydrolysates were sequentially fractionated by ultrafiltration using different membrane pore sizes (≤30, ≤10, ≤5 and ≤1 kDa) to obtain biopeptide fractions (BPF). The antioxidant capacity (AOX) of protein hydrolysates and BPF were evaluated. AOX was performed using 2,2´-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+), ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC) assays. after the enzymatic action of B. pinguin and B. karatas proteases, the highest DH values for egg, milk and soy protein hydrolysates ranged from 50-61%, 55-68% and 73-81%, respectively. The AOX was higher for soy hydrolysates than for egg and milk hydrolysates. Additionally, the highest AOX from ABTS and FRAP assays was observed for BPF ≤30 kDa, PF ≤5 kDa and ≤1 kDa, respectively. These results highlight the potential of B. pinguin and B. karatas proteases to hydrolyze food proteins and release bioactive peptides. Moreover, it has been shown that the hydrolysis products are a mixture of BP of different molecular weights, which could present AOX through different mechanisms.
Journal Article
EXPLORING THE MILK-CLOTTING PROPERTIES OF EXTRACTS FROM Bromelia pinguin FRUIT
Plants represent an attractive source of milk-clotting proteases with potential use for chymosin substitution in cheesemaking process. A crude enzymatic extract from B. pinguin fruit showed capacity to clot milk efficiently in a short time. It showed a maximum milk-clotting activity around 4 U/mL in the range of 70-80 ºC. This value indicated that one mL of the extract was capable to clot around 400 mL of milk in 40 min at the specified condition. B. pinguin extract presented only 25% of its maximum activity under standard temperature (30-35 ºC) for cheese-making. Proteases inhibitors indicated that cysteine and serine proteases were present in the extract and could be responsible for the milk-clotting activity found. SDS-PAGE analysis of casein hydrolysis indicated that proteases in B. pinguin extract were more proteolytic than chymosin. The high presence of milk-clotting proteases in B. pinguin fruit offers an alternative new source of proteases for biotechnological processes.
Journal Article
Effects of Bromelia pinguin (Bromeliaceae) on soil ecosystem function and fungal diversity in the lowland forests of Costa Rica
BACKGROUND: Bromelia pinguin (Bromeliaceae) is a terrestrial bromeliad commonly found under forest stands throughout the Neotropics that has been shown to have antifungal activity in vitro. We have hypothesized that this bromeliad would also have an effect on the fungal populations in nearby soil by decreasing fungaldiversity and negatively impacting C and N cycle-related activities. A previous study in the lowland forest of Costa Rica showed the soil beneath these bromeliads had decreased fungal ITS DNA and differences in C and N levels compared to adjacent primary forest soils. RESULTS: In this follow-up study, we found that the bromeliad soils had lower rates of C and N biomass development and lower phenol oxidase activity (suggesting less decreased fungal decomposition activity). The results of T-RFLP and cloning-based taxonomic analyses showed the community level diversity and abundance of fungal ITS DNA was less in bromeliad soils. Sequence analysis of fungal ITS DNA clones showed marked differences in fungal community structure between habitats of Basidiomycota (Tremellales, Agricales, Thelephorales), Ascomycota (Helotiales), and Zycomycota populations. CONCLUSIONS: The data show there to be differences in the soil nutrient dynamics and fungal community structure and activity associated with these bromeliads, as compared to the adjacent primary forest. This suggests the possibility that the anti-fungal activity of the bromeliad extends into the soil. The bromeliad-dense regions of these primary forest habitats provide a unique natural micro-habitat within the forests and the opportunity to better identify the role of fungal communities in the C and N cycles in tropical soils.
Journal Article
Purification and Characterization of Four New Cysteine Endopeptidases From Fruits of Bromelia pinguin L. Grown in Cuba
Bromelia pinguin
L. is a plant broadly distributed in Central America and Caribbean islands. The fruits have been used in traditional medicine as anthelmintic, probably owed to the presence of a mixture of cysteine endopeptidases, initially termed pinguinain. This work deals with the purification and characterization of the four main components of that mixture, two of them showing acid pI and the other two alkaline pI. Molecular masses (SDS-PAGE and MALDI-TOF), N-terminal sequence and the reactivity and kinetic parameters versus synthetic substrates (
p
-nitrophenyl-N-α-CBZ-amino acid esters, PFLNA, Z-Arg-Arg-
p
-NA, and Z-Phe-Arg-
p
-NA) of the studied peptidases are given, as well as the N-terminal sequences of the enzymes and the homology degree with other plant endopeptidases.
Journal Article
Happy Feet in a hostile world? The future of penguins depends on proactive management of current and predictable threats
Penguins face a wide range of threats. Most observed population changes have been negative and have happened over the last 60 years. Today, populations of 11 penguin species are decreasing. Here we present a review that synthesizes details of threats faced by the world's 18 species of penguins. We discuss alterations to their environment at both breeding sites on land and at sea where they forage. The major drivers of change appear to be climate, and food web alterations by marine fisheries. In addition, we also consider other critical and/or emerging threats, namely human disturbance near nesting sites, pollution due to oil, plastics and chemicals such as mercury and persistent organic compounds. Finally, we assess the importance of emerging pathogens and diseases on the health of penguins. We suggest that in the context of climate change, habitat degradation, introduced exotic species and resource competition with fisheries, successful conservation outcomes will require new and unprecedented levels of science and advocacy. Successful conservation stories of penguin species across their geographical range have occurred where there has been concerted effort across local, national and international boundaries to implement effective conservation planning.
Journal Article