Bioactive phytochemicals

Supercritical fluid extraction — During the past two decades, important progress was registered in the extraction of bioactive phytochemicals from plant or food matrices. Most of the work in this area focused on non-polar compounds (terpenoid flavors, hydrocarbons, carotenes) where a supercritical (SFE) method with CO2 offered high extraction efficiencies. Co-solvent systems combining CO2 with one or more modifiers extended the utility of the SFE-CO2 system to polar and even ionic compounds, e.g., supercritical water to extract polar compounds. This last technique claims the additional advantage of combining extraction and destruction of contaminants via the supercritical water oxidation process."... 

Carmen Socaciu was bom in Cluj-Napoca, Romania and earned a BSc in chemistry in 1976, an MSc in 1977, and a PhD in 1986 from the University Babes-Bolyai in Cluj-Napoca, an important academic centre located in the Transylvania region. Dr. Socaciu worked as a researcher in medical and cellular biochemistry for more than 10 years, and became a lecturer in 1990 and full professor in 1998 in the Department of Chemistry and Biochemistry of the University of Agricultural Sciences and Veterinary Medicine (USAMV) in Cluj-Napoca. She extended her academic background in pure chemistry (synthesis and instrumental analysis) to the life sciences (agrifood chemistry and cellular biochemistry). Her fields of competence are directed especially toward natural bioactive phytochemicals (carotenoids, phenolics, flavonoids), looking to advanced methods of extraction and analysis and to their in vitro actions on cellular metabolism, their effects as functional food ingredients, and their impacts on health. 

Some of the bioactive phytochemicals found in fmits and vegetables are polyphenols, including flavonoids. This chapter provides a general overview of the relationship between flavonoids and health. The mechanisms of action believed to be behind the healthful effects of some compounds will also be mentioned. 

Lila MA. 2007. The nature-versus-nurture debate on bioactive phytochemicals The genome versus terroir. J Sci Food Agric 86 2510-2515. 

Many bioactive phytochemicals were systematically studied after their fractionation and characterization from many vegetables and fruits. New biological effects such as the differentiation-inducing activity of carotenoids— particularly vitamin A—were described in the 1930s. In addition, several experimental results suggested that various carotenoids might serve as dietary chemopreventive agents [6] because of their ability to quench excited molecules and excess radicals. 

Piacente, S. Pizza, C. Oleszek, W., Saponins and phenolics of Yucca schidigera Roezl Chemistry and bioactivity, Phytochem. Rev., 2005, 4, 177-190. 

Table 13. Feeding deterrency (ECJ0 and 95% confidence limits) of bioactive phytochemicals on two chrysomelidae beetles [19].

Covers identification of bioactive phytochemicals from tree nut byproducts (where available) for u.se as functional food ingredients and nutraceuticals... 

Dihydro-a-pyrones substituted at C-6, also called a,p-unsaturated 5-lactones (Fig. 16), are bioactive phytochemicals produced by some plant species their versatile therapeutic effects have been associated with the presence of the a,p-unsaturated 8-lactone moiety. 

Avocado (Persea americana Mill) is an important tropical fruit and a good source of lipophilic phytochemicals such as monounsaturated fatty acids, carotenoids, vitamin E and sterols [46]. It has several cultivars that present great variation on time of fruit production and oil content in the pulp. Studies have indicated that the avocado oil is similar to olive oil and can be used in cosmetics and also for human consumption [47, 48]. New Zealand, Mexico, Chile United States and South America are among the main avocado oil producers. Avocado oil has the advantage that can be obtained from the fruit by means of a cold extraction methods, which is an easy and low technology that allow maintain in the oil significant amounts of the bioactive phytochemicals present in the fruit [47]. 

In Timisia, the olive oil sector plays an important role in the economy, providing both employment and export revenues. Olive trees cover an area of 1.6 million ha with an annual oil production of 170 000 t (Rigane et al., 2011). The last decade, Timisian autochthonous varieties were extensively studied for their potential with regard to VOO quality characteristics. The oils obtained from healthy fruits using laboratory scale extraction, most of the time with the aid of an Abencor type mill and extractor (Oueslati et al., 2009). Thus, the amoimts of bioactive phytochemicals reported are rather high in comparison to what is reported for VOOs from the main producing coimtries. This illusive picture does not reflect necessarily the real content of this nutrient in the commercial products sold locally or of those exported. 

Plant extracts are continuously being tested for bioactivity, and in cancer research, major enterprises for screens of antiproliferative activity are sometimes carried out. In one of these screens, nearly 70,000 species of terrestrial plants were tested against leukemia cell lines [95]. The authors labeled plant genera as hot if they yielded three or more plant species that showed activity in the screens. Six Psychotria species gave active extracts, so Psychotria earned the title of hot genus [95], This type of approach, extensive analysis of plant extracts in the search of bioactive phytochemicals, is very expensive, time-consuming, and labor-intensive, but can unveil precious new drug leads, as was the case with paclitaxel [96]. 

Kostova I, Dinchev D (2005) Saponins in Tribulus terrestris - chemistry and bioactivity. Phytochem Rev 4 111-137... 

Suresh D, Mahesha HG, Rao AGA, Srinivasan K (2007) Binding of bioactive phytochemical piperine with human serum albumin a spectrofluorometric study. Biopolymers 86 265-275... 

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