Pectin determination, extraction

The aim of the investigation was to study the influence of calcium and sodium ions, pectin containing extracts of aromatic vegetative raw materials and mumio on the carbopol gelation to develop the procedure of calcium and sodium ions mass part determination in extracts of aromatic vegetative pectin containing raw materials to establish the macro- and microelement composition of mumio. 

Arabinan. This highly soluble polymer is found in the extracts of many fmits and seeds, in the boiling water extracts of pine wood (127), in the extracts of marshmallow roots (A/t/jaea officina/is) (128), and aspen (63) and willow (Sa/ix a/ba F) (129) bark. Because arabinan can be isolated from mildly degraded pectin fractions, it is often difficult to determine whether it is a hemiceUulose or a labile fragment of a larger polysaccharide and/or lignin complex. Arabinans have a complex stmcture composed almost entirely of 5-linked a-L-arabinofuranosyl units with similar residues linked to them at C-2 and/or C-3 and is soluble in 70% aqueous methanol solution. 

Determination of Na " and Na" ions in raw cosmetic materials was conducted with the developed method of flame photometry. A necessity of development of method of samples preparation arose up in the work process, as this spicily-aromatic raw material contained pectin in amount 0.1-0.5% and that prevented preparation of samples by standard method of extracts dilution and required incineration of analyzed sample, time of analysis was increased in 60 times. It was established that CaCl, solution with the concentration 0,4 % caused destmctions of the carbopol gel. It was established that the addition of 0,1% CaCl, and 0,1% NaCl salts solutions into the system intensified the effect of negative action of these salts onto the gel stmcture and the gel destmcted completely. 

The determined macro- and microelement stmcture of mumio specifies onto the expediency of the application of this biologically active substance as a cosmetic raw material in the cosmetic compositions, which do not contain carbopol. The developed procedure for calcium and sodium ions determination in pectin-containing vegetative extracts is express and it is recommended for application at elaboration of cosmetic production compositions on the carbopol base. 

Table II. Carbohydrate compositions (weight percentage) of individual oligomer peaks purified (QAE-Sephadex or HPLC ion-exchange separation, respectively) from mixtures of citrus pectin oligomers or B fruit extracts Compositions shown are for peaks whose biological activity is described in Figure 4. Uronic acid values are based on colorimetric assay. Proportions of neutral sugars were determined by GC and adjusted so that totals equal 100%. In fact, some oligomers (G7 peaks 8, 9 and 10. B extract peak 10) produced small (less than 1 % of the total integrated area), unknown peaks in the GC chromatograms.

Enzyme Assay The crude enzyme was extracted from the solid state culture with 100 ml of 0.33% toluene at 4°C. The enzyme activity was assayed by the determination of substrate viscosity diminishing using Ostwald viscometer (5). The enzyme reaction was done at 37°C in 0.05 N acetate buffer pH 5.25. One unit of enzyme was defined as the amount of enzyme that could reduce the viscosity of 2% pectin by 50% in 10 min. 

In these experiments adult, male Fischer-344 rats were fed a purified diet, AIN-76A, containing 5 or 10% citrus pectin replacing cornstarch or one of two cereal based diets, Purina Rodent Chow 5002 and NIH-07. After 28 days of dietary treatment rats were given a single oral dose of tritiated DNT (10 or 75 mgAg). Twelve hours after dosing, animals were killed and CVB was determined by exhaustive extraction. The cecum was also excised from these animals and microflora characterized by anaerobic culture techniques (10). 

A more complex extraction scheme than those of Hewitt, Bowen, and Reilly described above, was used to show that 65Zn is primarily associated with pectin in the root residue (Peterson, 1968). This was modified and used to indicate the association of copper in Armeria maritima (Mill) Willdenow (Farago et al., 1980) and Ni in Hybanthus floribundus (Farago and Mahmoud, 1983). The scheme is shown Fig. 10-1, and some typical results are shown in Table 10-1. In these last two investigations radiotracers were not required, since the plants accumulated Cu and Ni, respectively, and metal determinations were carried out by flame atomic absorption spectrometry on the individual fractions. 

Since the determination of the water, oxalate and alkaline soluble pectin is just an extraction followed by a precipitation, this loss could be either the result of a poorer extractability or of a degradation into lower molecular weight pectin fractions which no longer can be precipitated by ethanol. Obviously the degradation is negligible, because the viscosity of pectin solutions which should be a sensitive indicator for the breakage of already few bonds is not altered by the application of HP. 

With the aid of the molar absorptivity value of 31600 at pH 10, as given by Fry (13), we have determined the feruloylester content of the four pectins. These are quite different (Table I). Acid-soluble and alkali-soluble pectins contain many more feruloylester groups on average one such group per pectin molecule. It is tempting to presume a relationship between feruloylester content and ease of extraction of the pectins, but this requires further study. 

Procedure. The method of acid extraction and demethylation of pectin from apple pomace at 60 C. was essentially that previously described (17), up to the point of clarification of the pectin extract. Prior to clarification, the temperature of the extract was raised to about 50 C. in order to aid dispersion of the pectinates. Following the clarification and removal of starch, the pectin was precipitated as calcium pectinate by adding 20% calcium chloride solution to the extract at room temperature. The quantity of calcium chloride was such that any excess of the salt did not give a further precipitate after the precipitated material had stood from 1 hour to overnight as a practical handling procedure. After the calcium pectinate had been filtered off through muslin by hand, the relative completeness of precipitation was estimated by determining the relative viscosity (Ostwald at 26 C.) of the liquid pressed out. A relative viscosity of 1.2 or less indicated practically complete precipitation. 

Pronic acid analysis. Carbazol colorimetric method (7) was used for the determination of total pectins in the dilute alkali extract of the alcohol-insoluble solids. The solution has to be diluted in order for the concentration to fall within the range of determination by this method. 

The extraction of pectin is determined by the intended field of application. If it is to act as a gelling agent, then the plants are extracted with water with the addition of acid, when pectin precipitates out on adding alcohol. Pectin as thickener is extracted with alkali. A distinction can be made between gelling agent grades with and without Ca ... 

Pectin in almond kernels can be determined by extracting ground samples with water (soluble pectins) and then 0.05 M HCL at 100 °C for 90 min (insoluble pectins). Pectins can be determined as uronic acid by the carbazole method, using galacturonic acid as standard (Bitter and Muir 1962). 

Liang and others in 2012 [48] used leaves of creeping fig Ficus pumila), a plant belonging to Moraceae, which is spread in Pacific Asia, China, Japan, the Philippines, and Taiwan. They determined that the pectin extracted had an LDE and achieved yields of6% (w/w) onadiy basis. They concluded that the extraction conditions impact the performance, biochemical characteristics. 

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