Search results for "Biochemistry"
showing 10 items of 20172 documents
Simultaneous determination of nine phytohormones in seaweed and algae extracts by HPLC-PDA.
2016
An RP-HPLC-PDA method for the simultaneous analysis of 9 compounds deriving from the phytohormones class was developed and optimized, namely indoleacetic acid (IAA), indolebutyric acid (IBA), phenyleacetic acid (PAA), naphtyleacetic acid (NAA), trans-zeatin (TZ), kinetin (KA), isopentenyladenine (IA), 6-benzylaminopurine (6-BA) and abscisic acid (ABA). Validation of the method was performed on the SFE-CO2 extract made out of the mixture of Baltic algae. The regression coefficients for plant hormones were in the range from 0.997 to 0.999. The LOD and LOQ were on the levels from 0.05–0.29 and 0.15–0.88 mg/L, respectively. Developed method was used for the separation and determination plant ho…
Effect of pH on malolactic fermentation in southern Italian wines
2018
This study investigated the influence of pH on malolactic fermentation (MLF) in white wines (adjusted to pH 3.2, 3.4 and 3.8, respectively) from Falanghina grapes and red wines (adjusted to pH 3.4 and 3.8, respectively) from Tintilia grapes. The wines were inoculated with Oenococcus oeni and Lactobacillus plantarum strains, and a mix of them (50:50), in red Tintilia only. The time required to complete MLF in wines from white Falanghina grapes at pH 3.4 and 3.8 was lower with O. oeni, while MLF did not occur at pH 3.2. In red Tintilia, MLF was always completed within 35 days; at high pH (3.8) a significant increase in histamine was detected, while the decrease in citric acid concentration ca…
An isoleucine-leucine substitution in chloroplastic acetyl-CoA carboxylase from green foxtail (Setaria viridis L. Beauv.) is responsible for resistan…
2002
The cDNAs encoding chloroplastic acetyl-CoA carboxylase (ACCase, EC 6.4.1.2) from three lines of Setaria viridis (L. Beauv.) resistant or sensitive to sethoxydim, and from one sethoxydim-sensitive line of Setaria italica (L. Beauv.) were cloned and sequenced. Sequence comparison revealed that a single isoleucine-leucine substitution discriminated ACCases from sensitive and resistant lines. Using near-isogenic lines of S. italica derived from interspecific hybridisation, we demonstrated that the transfer of the S. viridis mutant ACCase allele into a sethoxydim-sensitive S. italica line conferred resistance to this herbicide. We confirmed this result using allele-specific polymerase chain rea…
Effect on the Antioxidant, Lipoperoxyl Radical Scavenger Capacity, Nutritional, Sensory and Microbiological Traits of an Ovine Stretched Cheese Produ…
2021
An innovative ovine cheese enriched with red grape pomace powder (GPP) was produced to improve the functional properties of Vastedda cheese typology. Vastedda cheese making was performed adding GPP and four selected Lactococcus lactis strains (Mise36, Mise94, Mise169 and Mise190). For each strain, 40 L of pasteurized ewe’s milk was divided into two aliquots representing control and experimental trials. Control cheese (CC) production did not contain GPP, while the experimental cheese (EC) production was enriched with 1% (w/w) GPP. GPP did not slow down starter development and acid generation. Plate counts and randomly amplified polymorphic DNA (RAPD)-PCR analysis confirmed the dominance of t…
Silver Nanoparticles Affect Functional Bioenergetic Traits in the Invasive Red Sea Mussel Brachidontes pharaonis
2016
We investigated the functional trait responses to 5 nm metallic silver nanoparticle (AgNPs) exposure in the Lessepsian-entry bivalveB. pharaonis. Respiration rate (oxygen consumption), heartbeat rate, and absorption efficiency were evaluated across an 8-day exposure period in mesocosmal conditions. Basal reference values from not-exposed specimens were statistically compared with those obtained from animals treated with three sublethal nanoparticle concentrations (2 μg L−1, 20 μg L−1, and 40 μg L−1). Our data showed statistically significant effects on the average respiration rate ofB. pharaonis. Moreover, complex nonlinear dynamics were observed as a function of the concentration level and…
From elicitins to lipid-transfer proteins: a new insight in cell signalling involved in plant defence mechanisms.
2002
Elicitins and lipid-transfer proteins are small cysteine-rich lipid-binding proteins secreted by oomycetes and plant cells, respectively, that share some structural and functional properties. In spite of intensive work on their structure and diversity at the protein and genetic levels, the precise biological roles of lipid-transfer proteins remains unclear, although the most recent data suggest a role in somatic embryogenesis, in the formation of protective surface layers and in defence against pathogens. By contrast, elicitins are known elicitors of plant defence, and recent work demonstrating that elicitins and lipid-transfer proteins share the same biological receptors gives a new perspe…
Escaping the evolutionary trap: Can size-related contest advantage compensate for juvenile mortality disadvantage when parasitoids develop in unnatur…
2021
Abstract The quality of hosts for a parasitoid wasp may be influenced by attributes such as host size or species, with high quality for successful development usually coincident with high quality for larger offspring. This is not always the case: for the Scelionid wasp Trissolcus basalis, oviposition in eggs of the Brown Marmorated Stink Bug, Halyomorpha halys, rather than of the normal host, the Southern Green Stink Bug, Nezara viridula, leads to lower offspring survival, but survivors can be unusually large. Adult female T. basalis engage in contests for host access. As larger contestants are typically favoured in contests between parasitoids, the larger size of surviving offspring may co…
Dynamic complexities in host-parasitoid interaction
1999
In the 1970s ecological research detected chaos and other forms of complex dynamics in simple population dynamics models, initiating a new research tradition in ecology. However, the investigations of complex population dynamics have mainly concentrated on single populations and not on higher dimensional ecological systems. Here we report a detailed study of the complicated dynamics occurring in a basic discrete-time model of host-parasitoid interaction. The complexities include (a) non-unique dynamics, meaning that several attractors coexist, (b) basins of attraction (defined as the set of the initial conditions leading to a certain type of an attractor) with fractal properties (pattern of…
Environmental Variability and Semelparity vs. Iteroparity as Life Histories
2002
Research on the evolution of life histories addresses the topic of fitness trade-offs between semelparity (reproducing once in a lifetime) and iteroparity (repeated reproductive bouts per lifetime). Bulmer (1994) derived the relationship v+P(A)<1 (P(A) is the adult survival;vb(S) and b(S) are the offspring numbers for iteroparous and semelparous breeding strategies, respectively), under which a resident semelparous population cannot be invaded by an iteroparous mutant when the underlying population dynamics are stable. We took Bulmer's population dynamics, and added noise in juvenile and adult survival and in offspring numbers. Long-term coexistence of the two strategies is possible in much…
Effects of patch number and dispersal patterns on population dynamics and synchrony.
2000
In this paper, we examine the effects of patch number and different dispersal patterns on dynamics of local populations and on the level of synchrony between them. Local population renewal is governed by the Ricker model and we also consider asymmetrical dispersal as well as the presence of environmental heterogeneity. Our results show that both population dynamics and the level of synchrony differ markedly between two and a larger number of local populations. For two patches different dispersal rules give very versatile dynamics. However, for a larger number of local populations the dynamics are similar irrespective of the dispersal rule. For example, for the parameter values yielding stab…