Total lipid content, fatty acids and 4-desmethylsterols accumulation in developing fruit of Pistacia lentiscus L. growing wild in Tunisia

This research has determined oil, fatty acid and sterol contents of the Tunisian Pistacialentiscus (Lentisc) fruits during maturation. Low oil accumulation was observed during the first 35 days after the fruiting (DAF) date (from 1.83% to 2.57%). After that, two phases were distinguished (35th until the 60th and 105th to the 145th DAF), where the rate of oil accumulation increased significantly. At the last stage of maturation, the lentisc fruits had the highest percentage of lipid content, 42.54%. The changing profile of fatty acids during maturation had been marked mainly by an increase in oleic acid content (from 19.49% to 50.72%) paralleling a decrease in linoleic acid content (from 42.5% to 21.75%). At the 15th DAF, the alpha-linolenic acid was found with a maximum of 13.81%. At full maturity, the main fatty acids were oleic acid, followed by palmitic and linoleic acid. Other fatty acids were present in trace proportions, such as palmitoleic, stearic, linolenic, gadoleic and arachidic acid. In all stages of ripening only four sterols were identified and quantified. β-Sitosterol was the major 4-desmethylsterol in samples tested, followed by campesterol. Cholesterol and stigmasterol were detected in trace amounts. During the first stage of ripening, the amount of total sterols was about 5.19/100 g of oil. It decreased to 0.43/100 g in the last stage. Sitosterol and campesterol showed nearly the same profile during the ripening of P. lentiscus fruit which could be linked to the relation between these compounds during their biosynthesis.     

Fatty acid composition of seed oil of different Sorghum bicolor varieties

In order to find out new sources of premium quality edible oil in the country, seeds of ten varieties of Sorghum bicolor were initially analyzed for their total oil contents. The seed oil was later fractionated into eight fatty acids including two new saturated fatty acids. The oil contents were determined by Soxhlet method and compared with the results obtained by NMR analysis. The total oil contents in the seeds of sorghum ranged from 5.0 to 8.2 % (w/w), indicating non significant difference obtained by two different techniques. The results revealed that oleic acid (31.12–48.99%), Palmitoleic acid (0.43–0.56%), linoleic acids (27.59–50.73%), linolenic acid (1.71–3.89%), stearic acid (1.09–2.59%) and palmitic acid (11.73–20.18%) was present in the seed oil of different sorghum varieties when analyzed by GC–MS. It was observed that in most of the varieties polyunsaturated fatty acids (PUFA) were higher than monounsaturated fatty acids (MUFA). The two atypical SFAs, octanedioic (C8:0) and azelaic acid (C9:0) were found in some varieties. These results suggest that these S. bicolor varieties could be additional sources of edible oil due to presence of clinically important saturated and high concentration of unsaturated fatty acids. A large scale production of the seed oil after refining process can contribute towards alleviation of edible oil shortage in the country with increased use of premium quality oil.     

Chemical composition and DSC thermal properties of two species of Hylocereus cacti seed oil: Hylocereus undatus and Hylocereus polyrhizus

Two types of pitaya (Hylocereus cacti) seeds (Hylocereus undatus and Hylocereus polyrhizus) were investigated in this study. The fatty acid, phenolic, tocopherol, and sterol contents of the extracted seed oil were analysed. The results showed that the pitaya seeds contained a high amount of oil (18.33–28.37%). The three major fatty acids in the H. undatus seed oil (WFSO) and H. polyrhizus seed oil (RFSO) were linoleic, oleic, and palmitic acids. The total tocopherol contents in the WFSO and RFSO were 36.70 and 43.50 mg/100 g, respectively. The phytosterol compounds identified in the WFSO and RFSO were cholesterol, campesterol, stigmasterol, and β-sitosterol. Seven phenolic acid compounds were identified in the WFSO and RFSO, namely, gallic, vanillic, syringic, protocatechuic, p-hydroxybenzoic, p-coumaric, and caffeic acids. WFSO and RFSO can be differentiated by their T_off and T_on values in the DSC thermal curves. This study reveals that pitaya seed oil has a high level of functional lipids and can be used as a new source of essential oil.     

Influence of strawberry tree (Arbutus unedo L.) fruit ripening stage on chemical composition and antioxidant activity

Arbutus unedo is a widespread shrub with economic importance, derived from the use of its berries in the production of alcoholic beverages and in folk medicine. This work intends to evaluate for the first time the effect of fruit ripening stage on antioxidant activity, total phenolic content, fatty acid profile and tocopherol composition. Ripe fruits shown higher extraction yield (45.04 ± 2.23%) when compared to other fruit ripening stages. By contrast, total phenol contents were higher in the unripe and intermediate stage of ripeness (108 and 111 mg GAES/g dry fruit, respectively, against 60 mg/g dry fruit when ripe). Ripe and intermediate fruits shown the lower EC₅₀ values on the DPPH radicals (0.25 ± 0.02 mg/mL) and reducing power assay (1.09 ± 0.05 mg/mL), respectively. A significant correlation was established between antioxidant activity and fruits ripening stage. Fatty acid profiles were very similar between the ripening stages, being alfa-linolenic, linoleic and oleic, the three major ones. Polyunsaturated fatty acids (PUFA) represent as much as 60% of the total fatty acids, with a highly favorable omega 3/omega 6 ratio. From the analysis of the vitamin E vitamers, the most important was ??-tocotrienol, with a clear reduction in the total free vitamin E content with ripening.These results highlight that the fruits of intermediate ripeness can be regarded important sources of biologically active compounds with a fatty acid profile rich in omega-3 PUFA, properly supplemented with high vitamin E amounts.     

Nutritional composition of the kernels from Canarium album L.

The kernels from Canarium album L. (also called Chinese olive), largely cultivated in the southeast of China, were analyzed for their nutritional composition. The kernels had a high percentage of fats (52.8%) and proteins (29.5%). Soxhlet extracted kernel oil presented acid, iodine and saponification values of 0.56, 84.6 and 192, respectively. Gas chromatography–mass spectroscopy (GC–MS) analysis of kernel oil revealed that oleic acid (30.5%) and linoleic acid (41.8%) were the major unsaturated fatty acids, while palmitic acid (18.0%), stearic acid (7.83%) and arachidic acid (0.39%) were the main saturated ones. Potassium, calcium and magnesium were the predominant mineral elements present in the kernels. Sodium, iron, manganese and zinc were also detected in appreciable amounts. The kernel proteins were rich in arginine, glutamic and aspartic acids (3.19%, 5.02% and 2.47%, respectively) while the limiting amino acids were methionine and lysine.     

Complex formation, thermal properties, and in-vitro digestibility of gelatinized potato starch-fatty acid mixtures

Effects of the type and amount of fatty acid (0-2.0 mmol/g-starch of lauric, myristic, palmitic, stearic, oleic, and linoleic acids) on the complex formation, thermal properties, and in-vitro digestibility of gelatinized potato starch-fatty acid mixtures were investigated. Complex index (CI) evaluated by the reduction in the iodine binding capacity of starch increased with an increase in the amount of fatty acids, and reached a plateau depending on the type of fatty acid. The maximum CI value was higher in the order of lauric (49.9%), linoleic (47.6%), myristic (42.4%), oleic (36.7%), stearic (35.3%), and palmitic acid (30.9%). From the calorimetric study, it was demonstrated that melting temperature of the complexes was higher in the order of stearic (96.7 °C) > lauric, myristic, palmitic, and oleic (89.6-92.1 °C) > linoleic acid (78.3 °C). Melting enthalpy for complexes was roughly related to the CI value (R² = 0.667). From the in-vitro digestibility measurement, it was found that a certain amount of fatty acid reduced the starch content hydrolyzed at a given condition. Among them, 0.50 mmol/g-starch lauric and oleic acid samples showed the largest reduction in the hydrolyzed starch content. This result was related to the extent of complex formation characterized by CI value and its helical order characterized by melting temperature. In addition, there was a possibility of the complex formation between amylose and unsaturated fatty acid during the hydrolysis of gelatinized starch.     

Variation in the composition of Cretan avocado cultivars during ripening

The effect of ripening on the chemical characteristics of fruits of the avocado (Persea americana) cultivars Ettinger, Fuerte and Hass was investigated. A study of some quality parameters of these main avocado cultivars grown on the island of Crete was performed. As the fruit ripened, a decrease in the moisture content was observed, with a high degree of correlation for all the cultivars. At the same time an increase in the fat and protein contents was measured. The content of total sugars was high in the unripe fruit but decreased during ripening. The fatty acid composition of the oil extracted from the fruit pulp was determined by gas chromatographic analysis. The oil of the edible portion of the fruit was rich in oleic, palmitic, linoleic and palmitoleic acids, while stearic acid was present in small quantities. During the ripening process the amount of palmitic acid decreased and that of oleic acid increased in all the cultivars. The ratio of polyunsaturated to saturated fatty acids, which is considered as an indicator of the nutritional value of the fruit, was also calculated. No significant differences were observed between the cultivars. Principal component analysis was also performed to examine the relationship among the quality variables of the cultivars. From these data, Fuerte was considered to be the cultivar with the best characteristics. Copyright © 2004 Society of Chemical Industry     

Evaluation and characterisation of Citrullus colocynthis (L.) Schrad seed oil: Comparison with Helianthus annuus (sunflower) seed oil

The physicochemical properties, fatty acid, tocopherol, thermal properties, ¹H NMR, FTIR and profiles of non-conventional oil extracted from Citrullus colocynthis (L.) Schrad seeds were evaluated and compared with conventional sunflower seed oil. In addition, the antioxidant properties of C. colocynthis seed oil were also evaluated. The oil content of the C. colocynthis seeds was 23.16%. The main fatty acids in the oil were linoleic acid (66.73%) followed by oleic acid (14.78%), palmitic acid (9.74%), and stearic acid (7.37%). The tocopherol content was 121.85 mg/100 g with γ-tocopherol as the major one (95.49%). The thermogravimetric analysis showed that the oil was thermally stable up to 286.57 °C, and then began to decompose in four stages namely at 377.4 °C, 408.4 °C, 434.9 °C and 559.2 °C. The present study showed that this non-conventional C. colocynthis seed oil can be used for food and non-food applications to supplement or replace some of the conventional oils.     

Assessment and profiling of the fatty acids in two ackee fruit (Blighia sapida Köenig) varieties during different ripening stages

BACKGROUND: The ripening of fruits is characterized by physical, chemical and biochemical compositional changes such as color, sugars and phenolic compounds. Ackee fruit is famous in Jamaica and the Caribbean. This study aimed to assess the variation of fatty acids in two varieties (cheese and butter) ackee (Blighia sapida) fruits during five different ripening stages. RESULTS: The total fatty acid content of ackee fruit was much higher in arils and ranged from 283.4 to 465.1 g kg^?1 dry weight (DW), while in husk they ranged from 235.2 to 465.1 g kg^?1 DW in both varieties. Total fatty acid content declined in the arils and the husks as the fruit ripened. Five major fatty acids were found: palmitic acid (C16:0) and stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2) and linolenic acid (C18:3). In the arils, oleic acid was found at the highest concentration, followed by palmitic, stearic, linoleic and last linolenic acid. The unsaturated:saturated ratio of fatty acids varied from 1.23 to 3.26 in the arils of both varieties, and from 1.03 to 5.05 in the husk. Monounsaturated:polyunsaturated fatty acids ranged from 8.56 to 25.19 in the arils and from 0.62 to 2.33 in the husk. CONCLUSION: The results show that ackee arils contain much higher levels of fats than the husk and the major fatty acid in the arils was oleic acid (Δ9‐cis‐oleic acid, an omega n‐9), while in the husk unsaturated fatty acids were higher than the saturated ones. Oleic acid was the major fatty acid in both varieties, and aril fatty acid content was 10–20 times higher than in the husk. In both varieties, unsaturated fatty acids were relatively higher than saturated ones; however, total fatty acids showed a decline with ripening for arils and husk tissues. © 2012 Society of Chemical Industry     

Chemical composition and functional properties of Ulva lactuca seaweed collected in Tunisia

The chemical composition and some functional properties of the dried “Ulva lactuca” algae, collected from the littoral between the Taboulba and Sayada area, were determined. The dried “U. lactuca” algae were investigated for their soluble, insoluble and total dietary fibre content, mineral amount, amino acid and fatty acid profiles, swelling capacity (SWC), water holding capacity (WHC) and oil holding capacity (OHC). Results showed that “U. lactuca” alga powder was characterised by a high content of fibres (54.0%), minerals (19.6%), proteins (8.5%) and lipids (7.9%). The neutral fibres contain hemicellulose (20.6%), cellulose (9.0%) and lignin (1.7%). The proteinic fraction analysis indicated the presence of essential amino acids, which represent 42.0% of the total amino acids. The fatty acids profile was dominated by the palmitic acid, which represents about 60.0% of the total fatty acids, followed by oleic acid (16.0%). The study of the functional properties proved that SWC, WHC and OHC of this alga varied with temperatures and that were comparable to those of some commercial fibre rich products.     

Characteristics of Prunus serotina seed oil

Oils from Prunus serotina raw and toasted seeds extracted with hexane and supercritical CO₂ were evaluated for their physicochemical characteristics. Supercritical CO₂ extracted the least oil (21.3%), with high absorbing carotenoid pigments. P. serotina oil had characteristically high refractive index and density with three typical absorbance peaks in the UVC (100–290 nm) range centred at 260, 270 and 280 nm. The oil was highly polyunsaturated and abundant in oleic (35%), α-elostearic (27%), linoleic (27%), palmitic (4%), stearic (4%) and β-elostearic (1%) acids. P. serotina seed oil exhibited at least three distinct thermal structural transitions between −35 and −13 °C with two reversing transitions between −19 and −12 °C. Thermal oxidation by differential scanning calorimetry (DSC) revealed a three step oxidation of P. serotina seed oil with the mean onset and oxidation temperatures at 121 and 130–273 °C, respectively, depending on processing. Supercritical CO₂ extraction and toasting significantly affected the thermal and oxidation characteristics, fluorescence, and fatty acids of oils.     

Dynamic accumulation of 4-desmethylsterols and phytostanols during ripening of Tunisian Meski olives (Olea europea L.)

Eleven 4-desmethylsterols and two phytostanols were identified by GC–MS during the ripening of Meski olive. The maximum levels of 4-desmethylsterols (1300 mg/100 g oil) and phytostanols (7.5 mg/100 g oil) were reached at the 26th week after the flowering date (WAFD) of fruit. β-Sitosterol (72–86% of total 4-desmethylsterols) was the major 4-desmethylsterols during the maturity of fruit, while sitostanol was the predominant phytostanols (75–85% of total phytostanols). Δ5-Avenasterol (2–18%) and campesterol (1.6–4%) were the second and the third 4-desmethylsterol levels detected, respectively, during the ripening of Meski olive. The levels of campestanol varied from 15% to 25% of phytostanols. The rate of accumulation of those compounds occurred before 30th WAFD. Some of these compounds (4-desmethylsterols and phytostanols) showed nearly the same profile during the ripening of Meski olive which could be linked to the relation between these compounds during their biosynthetic pathway.     

Fatty acids of neutral and phospholipids of three endangered trout: Salmo trutta caspius Kessler, Salmo trutta labrax Pallas and Salmo trutta macrostigma Dumeril

Total (TL), neutral (NL) and phospholipid (PL) amounts and fatty acid (FA) composition of female Salmo trutta caspius, Salmo trutta labrax and Salmo trutta macrostigma were investigated during one year. Twenty-three FAs were identified in both NLs and PLs. The principal FAs of both fractions were palmitic acid in saturated fatty acid, oleic acid in monounsaturated fatty acid, docosahexaenoic acid (DHA) in n-3 polyunsaturated fatty acids (n-3 PUFAs) and linoleic acid in n-6 PUFAs. The highest values for TLs, NLs and PLs were found in winter. As a general trend, the highest n-3/n-6 ratios and eicosapentaenoic acid (EPA) + DHA amounts were found in the winter and this coincided with the lowest gonado-somatic index.     

Crude palm oil from interspecific hybrid Elaeis oleifera × Elaeis guineensis: Fatty acid regiodistribution and molecular species of glycerides

The composition and structure of triacylglycerols (TAGs) and partial glycerides of crude palm oil obtained from interspecific hybrid Elaeis oleifera × Elaeis guineensis, grown in Colombia, were fully characterised and compared to data obtained by analysing crude African palm oil. Hybridisation appears to substantially modify the biosynthesis of fatty acids (FAs) rather than their assembly in TAGs. In fact, total FAs analysis showed significant differences between these two types of oil, with hybrid palm oil having a higher percentage of oleic acid (54.6 ± 1.0 vs 41.4 ± 0.3), together with a lower saturated fatty acid content (33.5 ± 0.5 vs 47.3 ± 0.1), while the percentage of essential fatty acid, linoleic acid, does not undergo significant changes. Furthermore, 34 TAG types were identified, with no qualitative differences between African and E. guineensis × E. oleifera hybrid palm oil samples. Short and medium chain FAs (8:0, 10:0, 12:0, 14:0) were utilised, together, to build a restricted number of TAG molecular species. Oil samples from the E. guineensis × E. oleifera hybrid showed higher contents of monosaturated TAGs (47.5–51.0% vs 36.7–37.1%) and triunsaturated TAGs (15.5–15.6% vs 5.2–5.4%). The sn-2 position of TAGs in hybrid palm oil was shown to be predominantly esterified with oleic acid (64.7–66.0 mol% vs 55.1–58.2 mol% in African palm oil) with only 10–15% of total palmitic acid and 6–20% of stearic acid acylated in the secondary position. The total amount of diacylglycerols (DAGs) was in agreement with the values of free acidity; DAG types found were in agreement with the representativeness of different TAG species.     

Changes in fatty acid and essential oil composition of sage (Salvia officinalis L.) leaves under NaCl stress

Fatty acids and essential oils from hydroponically cultivated Salvia officinalis leaves were analyzed by GC and GC–MS. Four different levels of NaCl (25, 50, 75 and 100 mM) were applied. The first results showed that salt treatment reduced significantly the plant growth by 61% and the total fatty acids (TFA) content by 32% at 100 mM NaCl. Alpha-linolenic, gadoleic, palmitic and oleic acids were the major fatty acids. Moreover, the polyunsaturated fatty acids decreased, while the monounsaturated ones increased with respect to increasing salinity. Regarding the essential oil composition, the main compounds were α-and β-thujone, 1,8-cineole, camphor, α-humulene, viridiflorol and manool at all salt treatments. The yield had a maximum increase at 75 mM NaCl. Hence, sage can be considered as moderately salt sensitive.     

GC-MS quantification of fatty acid profile including trans FA in the locally manufactured margarines of Pakistan

Ten margarine brands of Pakistan were analyzed for their fatty acid composition with emphasis on trans fatty acids (TFA) using GC-MS. Saturated, cis-monounsaturated and polyunsaturated fatty acids were present at 24.2–58.1, 5.7–35.4 and 3.8–37.4% of total fatty acids, respectively. Among the saturated fatty acids, palmitic acid (16.9–33.8%) was dominant in all analyzed margarine brands and its higher amount indicates that palm oil was a major contributor in the margarine manufacturing. Among samples tested only one contained a low level of TFA (2.2%) while the rest contained very high amounts of TFA (11.5–34.8%) which clearly shows that hydrogenated oils were used in the formulation of margarines. Fatty acid profiles demonstrated that all samples belong to the hard margarine category containing high amounts of trans and saturated fatty acids which is an alarming issue for the health of consumers.     

Chemical,amino acid and fatty acid composition of Sterculia urens L. seed

The chemical, amino acid and fatty acid compositions of Sterculia urens seeds are reported. The cotyledons were found to be rich in protein (30.88%) and lipids (39.2%). The major amino acids in defatted Sterculia urens cotyledon flour (DSCF) were determined as glutamic acid, arginine and aspartic acid. Cysteine, methionine, tyrosine and histidine were observed in minor quantities. The ratio of essential to non-essential amino acids was observed to be 0.45. Among the essential amino acids, isoleucine was found to be higher than the reported FAO/WHO requirements. The GC-FID and GC–MS analysis revealed that the major fatty acids of the total lipid were stearic acid (31.72%), linoleic acid (28.83%) and palmitic acid (26.79%). Eicosadienoic acid (4.98%) and eicosatrienoic acid (2.96%) were also found in the total lipid.     

Chemical analysis and preliminary toxicological evaluation of Garcinia mangostana seeds and seed oil

The chemical analysis and preliminary toxicological evaluation of Garcinia mangostana seeds and seed oil have been investigated in order to determine the possibility of using them for human and/or animal consumption. Proximate analysis showed that the seeds had high amount of carbohydrate and were rich in oil (21.68 ± 6.18%) but have a low protein content. The physical properties of the oil extracts showed the state to be liquid at room temperature (25 ± 1 °C) and the colour of the oil golden-orange. The specific gravity of the oil was 0.98 ± 0.01. Among the chemical properties of the oil extracts, acid value, saponification number, iodine value, percent free fatty acid and peroxide value compared well with those of conventional edible oils. The seed flour was found to be a good source of minerals. It contained considerable amounts of potassium (7071 mg/kg), magnesium (865 mg/kg) and calcium (454 mg/kg). Fatty acid composition of the seed oil indicated that the oil contained one essential fatty acids small proportions: linoleic acid (1.30%). The most prevalent fatty acids were palmitic acid (49.5%) and oleic acid (34.0%). Weanling albino rats appeared to suffer no toxicological effects when fed with G. mangostana seed oil in their diet for 8 weeks. Weekly monitoring of the rats showed good physical appearance and steady weight increase. Histological examination of sections of the heart, liver, kidney, spleen and lung revealed that the kidney of some of the rats had some degrees of pathology which included diffuse glomerular and tubular degeneration. No lesion was found in the heart and liver of the rats. The seed oil could be useful as an edible oil and for industrial applications.     

Assessment of the antioxidant potential and fatty acid composition of four Centaurea L. taxa from Turkey

This paper focused on the assessment of antioxidant property and fatty acid composition of four Centaurea species. The antioxidant activity of its methanol extract was evaluated by several in vitro experiments including phosphomolybedum assay, DPPH assay, β-carotene/linoleic acid, ferric and cupric reducing power. Total phenolic and flavonoid contents were also evaluated. The methanol extract of Centaurea pulcherrima var. pulcherrima showed the superior free radical scavenging activity, linoleic acid inhibition capacity, reducing power and also had the highest total phenolic content. A significant relationship between antioxidant capacity and total phenolic components was found. The oils of Centaurea taxa were also analysed for fatty acid concentration by gas chromatography. The principal fatty acids in the species were palmitic acid (23.38–30.49%) and linoleic acid (20.19–29.93%). These findings suggest that the Centaurea species could be used as a potential source of new natural antioxidants and unsaturated fatty acids in food industry, cosmetics and pharmaceutical preparations.     

New trends in the seafood market. Sutchi catfish (Pangasius hypophthalmus) fillets from Vietnam: Nutritional quality and safety aspects

Sutchi catfish (Pangasius hypophthalmus) produced in the freshwater basins of Vietnam, available on the Italian market as frozen or thawed fillets, were studied for their nutritional quality and safety aspects. Proximate composition, mineral content, fatty acid profile, unsaponifiable components of the lipid fraction and drip loss during thawing at 5 °C were determined on the fillets. Fillets were characterised by high moisture levels (80–85%) and low protein (12.6–15.6%) and lipid (1.1–3.0%) contents. Total lipids were characterised by low cholesterol levels (21–39 mg/100 g), high percentages of saturated fatty acids (41.1–47.8% of total fatty acid) and low percentages of polyunsaturated fatty acids (12.5–18.8% of total fatty acids), which were mainly represented by linoleic acid (44–59% of total polyunsaturated fatty acids). The mineral composition was characterised by a high sodium content (222–594 mg/100 g), probably partially due to the sodium tripolyphosphate (E 451) used to retain moisture. As regards safety aspects, the quality of the samples analysed was good, with low residue levels of mercury, organochlorine pesticides and polychlorinated biphenyls.