The dietary consumption of grape and its products is associated with a lower incidence of degenerative diseases such as cardiovascular disease and certain types of cancers. Most recent interest has focused on the bioactive phenolic compounds in grape. Anthocyanins, flavanols, flavonols and resveratrol are the most important grape polyphenols because they possess many biological activities, such as antioxidant, cardioprotective, anticancer, anti-inflammation, antiaging and antimicrobial properties. This review summarizes current knowledge on the bioactivities of grape phenolics. The extraction, isolation and identification methods of polyphenols from grape as well as their bioavailability and potential toxicity also are included.

https://www.mdpi.com/1422-0067/11/2/622/pdf

Biological Activities of Polyphenols from Grapes

Biocompatibility of β-stabilizing elements of titanium alloys

Engineering biocompatible implant surfaces

Basic biochemical mechanisms behind the health benefits of polyphenols.

With an ageing population, war, and sports related injuries there is an ever-expanding requirement for hard tissue replacement such as bone. Engineered artificial scaffold biomaterials with appropriate mechanical properties, surface chemistry and surface topography are in a great demand for enhancing cell attachment, cell growth and tissue formation at such defect sites. Most of these engineering techniques are aimed at mimicking the natural organization of the bone tissues and thereby create a conducive environment for bone regeneration. As the interaction between the cells and tissues with biomaterials at the tissue–implant interface is a surface phenomenon, surface properties play a major role in determining both the biological response to implants and the material response to the physiological condition. Hence surface engineering of biomaterials is aimed at modifying the material and biological responses through changes in surface properties while still maintaining the bulk mechanical properties of the implant. Therefore, there has been a great thrust towards development of Ca–P-based surface coatings on various metallic and nonmetallic substrates for load bearing implant applications such as hip joint prosthesis, knee joint prosthesis and dental implants. Typical coating methodologies like ion beam assisted deposition, plasma spray deposition, pulsed laser physical vapor deposition, magnetron sputtering, sol–gel derived coatings, electrodeposition, micro-arc oxidation and laser deposition are extensively studied at laboratory scale. In the present article, attempts are made to give an overview of the basic principles behind the coating techniques as well as advantageous features such as bioactivity and biocompatibility associated with these coatings. A strong emphasis will be given on laser-induced textured and bioactive coatings obtained by the author's research group [A. Kurella, N.B. Dahotre, Journal of Biomedical Applications 20 (2005) 5–50; A. Kurella, N.B. Dahotre, Acta Biomaterialia 2 (2006) 677–688; A. Kurella, N.B. Dahotre, Journal of Minerals, Metals and Materials Society (JOM) 58 (2006) 64–66; A. Kurella, N.B. Dahotre, Journal of Materials Science: Materials in Medicine 17 (2006) 565–572; P.G. Engleman, A. Kurella, A. Samant, C.A. Blue, N.B. Dahotre, Journal of Minerals, Metals and Materials Society (JOM) 57 (2005) 46–50; R. Singh, A. Kurella, N.B. Dahotre, Journal of Biomaterials Applications 21 (2006) 46–72; S.R. Paital, N.B. Dahotre, Biomedical Materials 2 (2007) 274–281; S.R. Paital, N.B. Dahotre, 2009, Acta Biomaterialia, doi:10.1016/j.actbio.2009.03.004 ; R. Singh, N.B. Dahotre, Journal of Materials Science: Materials in Medicine 18 (2007) 725–751.]. Since cells are sensitive to topographical features ranging from mesoscale to nanoscale, formation of these features by both pulsed and continuous wave Nd:YAG laser system will be highlighted. This can also be regarded as advancement towards third generation biomaterials which are bioinert, bioactive and which once implanted will stimulate cell adhesion, proliferation and growth at the interface. Further, an overview of various bio-implants and bio-devices and materials used for these kinds of devices, performance factors such as mechanical and corrosion behavior and surface science associated with these materials are also explained. As the present article is aimed at describing the multidisciplinary nature of this exciting field it also provides a common platform to understand this subject in a simple way for students, researchers, teachers and engineers in the fields ranging from medicine, dentistry, biology, materials science, biomedicine, biomechanics to physics.

Calcium phosphate coatings for bio-implant applications: Materials, performance factors, and methodologies

The influence of niobium and vanadium on passivity of titanium-based implants in physiological solution.

Electrochemical–corrosion properties of Ti, Ti6Al6Nb and Ti6Al4V implant materials coated with calcium phosphate (CaP) coatings were investigated in vitro at the open circuit potential using non-destructive electrochemical impedance spectroscopy (EIS) technique in simulated physiological-Hank's Balanced Salt Solution (HBSS). Characterization of the structure and composition of CaP coatings obtained by the sol–gel method was performed using X-ray diffraction analysis. The interpretation of the EIS results was based upon a two-layer model of the surface film consisting of an inner barrier TiO2 (CaTiO3) layer and the outer porous hydroxyapatite (HAP)+β-tricalcium phosphate (β-TCP) layer, described by using the high frequency time constant (τ1HF) and the low frequency time constant (τ2LF), respectively. Spontaneously passivated surfaces of naturally grown surface films on all three substrates in HBSS were used for reference. The chemical composition of the substrate as well as the composition and crystallinity of the CaP coating have a direct influence on electrochemical–corrosion properties of the implant materials under in vitro conditions. Well-crystallized HAP and β-TCP exhibited a beneficial corrosion protection effect on the substrate during prolonged exposure to HBSS. In the case of poorly crystallized coatings containing a greater amount of carbonate incorporated in the structure of HAP, the total impedance of the system markedly changed with prolonged exposure to physiological solution due to degradation of the coating.

An in vitro study of Ti and Ti-alloys coated with sol–gel derived hydroxyapatite coatings

Catechin antioxidant action at various pH studied by cyclic voltammetry and PM3 semi-empirical calculations

Plavac mali and Zinfandel (syn. Primitivo) ( Vitis vinifera L.) have previously been shown to be distinct cultivars but close relatives. They were analyzed, together with 33 cultivars from vineyards in the Croatian region of Dalmatia, at 16 to 25 microsatellite loci in order to further investigate their relationship to each other. Microsatellite alleles and subsequent likelihood analysis showed with a very high degree of probability that Plavac mali is the progeny of Zinfandel and Dobrieiae. The shoot tips of Plavac mali are similar to those of Zinfandel, while its mature leaves reflect the influence of both parents. All three have similar berry and cluster morphology. Zinfandel is earlier than Plavac mali and Dobrieiae with respect to both budbreak and fruit ripening. Many of the alleles present in Zinfandel and Dobrieiae are more common in the Croatian gene pool than in the general population of V. vinifera cultivars. This observation, together with our finding that four additional Croatian cultivars are closely related to Zinfandel, leads us to conclude that Zinfandel originated in Croatia. Vines of the cultivars Crljenak kastelanski and Pribidrag, found in two different locations in Dalmatia in 2001 and 2002, respectively, were shown to match the microsatellite genotype of Zinfandel.

Zinfandel, Dobricic, and Plavac mali: The Genetic Relationship among Three Cultivars of the Dalmatian Coast of Croatia

In this study, we discovered that flavonoids belonging to the subclasses: (flavanone, flavone, and flavonol) display differential effects on the synthesis of collagen in human dermal fibroblasts. At 80 μg/ml flavonoids quercetin-3,3′,4′, 5,7-pentahydroxyflavone, 3-methyl quercetin, and 7-hydroxyflavone significantly decreased the total protein concentration which was a direct consequence of their cytotoxic effect, while naringenin exhibited no effect on total collagen and total protein concentration. Quercetin-3,3′4′,7-tetramethyl ether, 4′-hydroxyflavanone, flavanone, and fisetin significantly decreased collagen concentration while morin, rutin, and chrysin increased collagen concentration without changing the overall protein concentration. The initial screening performed in this study enables the identification of compounds that exert significant effects on fibroblast function and show potential as starting material for pharmaceutical preparations targeted against various disorders centered around disturbed collagen metabolism.

Jasenka Piljac

Papers

The influence of niobium and vanadium on passivity of titanium-based implants in physiological solution.

An in vitro study of Ti and Ti-alloys coated with sol–gel derived hydroxyapatite coatings

Catechin antioxidant action at various pH studied by cyclic voltammetry and PM3 semi-empirical calculations

Zinfandel, Dobricic, and Plavac mali: The Genetic Relationship among Three Cultivars of the Dalmatian Coast of Croatia

Effect of different flavonoids on collagen synthesis in human fibroblasts.