Fatty acid, tocopherol composition and the antioxidant activity of the lipid extract from the sorghum grains growing in Algeria

Biochemical composition of selected lines from sorghum (Sorghum bicolor L.) landraces

Present findings revealed a great variation in protein, oil, starch, tannin and phytic acid-like biochemical attributes of sorghum genotypes. GT bi-plot analysis was used for assessment of biochemical analysis results. Sorghum is quite resistant to negative environmental conditions. Thus, it has become the basic source of nutrient in majority of developing countries. It is also used as a supporting product against several diseases. In this study, biochemical composition of new 154 sorghum lines, selected from Turkish sorghum landraces through morphological, biochemical and molecular studies, was determined. Present findings revealed based on average of two years that crude protein content of 80 lines (> 9.65%), digestible protein content of 94 lines (> 56.25%), crude oil content of 75 lines (> 3.87%), resistant starch ratio of 32 lines (> 3.93%), starch content of two lines (> 77.07%) and amylose content of 10 lines (> %25.26) were greater than standard cultivar with the greatest values and amylopectin contents of 74 lines (< 47.75%) were lower than the standard cultivar with the lowest values. As the average of years, phytic acid contents and condense tannins contents of the lines, respectively, varied between 0.02 (IS 12850/1)-6.49% (PI 177161 03/2) and 0.09 (IS 12819/1)-5.38% (PI 255738 02/3). With this study, several sorghum lines superior than the standard cultivars were identified. Those lines can be used for direct cultivar registration in short run and can be used as parent materials in further breeding studies to be conducted for various purposes in long run.

Losses of nutrients and anti-nutrients in red and white sorghum cultivars after decorticating in optimised conditions

The aims were to optimise pearling process of red and white sorghum by assessing the effects of pearling time and grain moisture on endosperm yield and flour ash content and to assess nutrient and anti-nutrient losses produced by pearling different cultivars in optimised conditions. Both variables significantly affected both responses. Losses of ashes (58%), proteins (9.5%), lipids (54.5%), Na (37%), Mg (48.5%) and phenolic compounds (43%) were similar among red and white hybrids. However, losses of P (30% vs. 51%), phytic acid (47% vs. 66%), Fe (22% vs. 55%), Zn (32% vs. 62%), Ca (60% vs. 66%), K (46% vs. 61%) and Cu (51% vs. 71%) were lower for red than white sorghum due to different degree of extraction and distribution of components in the grain. Optimised pearling conditions were extrapolated to other hybrids, indicating these criteria could be applied at industrial level to obtain refined flours with proper quality and good endosperm yields.

Lipids characterization of ultrasound and microwave processed germinated sorghum

Background

Cereal crops and oilseeds provide diverse pool of fatty acids with characteristic properties. Sorghum (Sorghum bicolor (L.) Moench) provides the staple food with serving as main source of energy and protein. Germination of sorghum generally increases the nutritive value of seeds and the effects of germination on lipids composition of seeds vary greatly with processing conditions. Therefore, the current study was conducted to compare the effect of emerging processing techniques such as ultrasound (US) and microwave (MW) on fatty acids composition and oil yield of sorghum seeds before and after germination.

Methods

Initially sorghum grains were soaked with 5% NaOCl (sodium hypochlorite) for surface sterilization. Afterwards, grains were soaked in excess water for 22 h at room temperature and were divided into four portions. The first portion (100 g grains) was subjected to germination without applying any microwave and ultrasonic treatment (T₀). Second portion was further divided into four groups (T₁, T₂, T₃, T₄) (100 g of each group) and grains were subjected to ultrasonic treatments using two different ultrasonic intensities (US₁: 40%; US₂: 60%) within range of 0–100% and with two different time durations (t_US1: 5 min; t_US2: 10 min) at constant temperature. Third portion was also divided into four groups (T₁, T₂, T₃, T₄) (100 g of each group) and exposed to microwave treatments at two different power levels (MW₁: 450 watt; MW₂: 700 watt) within the range of 100-900 W for two different time durations (t_MW1: 15 s; t_MW2: 30s). Similarly, fourth portion was divided into four groups (T₁, T₂, T₃, T₄) (100 g of each group). Each group was exposed to both MW (MW₁, MW₂) (100–900 watt power) & US (US₁, US₂) (0–100% intensity) treatments at two different time levels (t_US, t_MW). Then, germination was carried out and pre-treated raw and pre-treated germinated sorghum grains were analyzed for total oil yield, fatty acid composition and unsaturated fatty acids (Un-SFA)/saturated fatty acids (SFA) ratio by gas chromatography.

Results

The results revealed that oil yield in sorghum before and after germination ranged from 6.55 to 7.84% and 6.28 to 7.57%, respectively. All the microwave and ultrasound processed samples showed significant difference in oil yield than the raw sorghum grains. The highest tested yield was 7.84 ± 0.31% when combination of microwave power (700 W) and ultrasound intensity (60%) was applied for 30s and 10 min, respectively. The results further demonstrate that the raw sorghum contained palmitic (13.73 ± 0.10%), palmitoleic (0.43 ± 0.02%), stearic (1.07 ± 0.04%), oleic (37.15 ± 0.10%), linoleic (43.33 ± 0.21%), linolenic (1.55 ± 0.04%), arachidic acid (0.13 ± 0.01%) and eicosenoic acid (0.37 ± 0.02%), respectively. The highest fatty acid percentage for palmitic, stearic and arachidic acid was 13.75 ± 0.07%, 1.11 ± 0.09% and 0.15 ± 0.03% at 60% US intensity for 10 min (T₄), respectively. Maximum amount observed was 1.60 ± 0.09% of linolenic acid while amount of eicosenoic acid decreased from 0.37 ± 0.02% to 0.31 ± 0.01% after processing. In case of applying combination of microwave and sonication treatments, the change in eicosenoic acid increased from 0.35 ± 0.02% to 0.40 ± 0.04% while there was no significant change in other fatty acids. The ungerminated sorghum oil possessed 14.93–15.05% and 82.83–83.12% of SFA and Un-SFA, respectively. After germination, percentage of saturated fatty acids increased (16.4–16.55%) while decreased for unsaturated fatty acids (80.13–80.56%) were noted.

Conclusions

The results of the present study conclude that the yield of oil from sorghum grains increased by emerging processing. Fatty acid analysis of sorghum oil suggested that pre-treatment strategies will not affect the quality of the oil with respect to essential fatty acids content. Overall, the composition of saturated fatty acid in germinated grain is improved than ungerminated grains after processing.

Sorghum (Sorghum bicolor L.): Nutrients, bioactive compounds, and potential impact on human health

Sorghum is the fifth most produced cereal in the world and is a source of nutrients and bioactive compounds for the human diet. We summarize the recent findings concerning the nutrients and bioactive compounds of sorghum and its potential impact on human health, analyzing the limitations and positive points of the studies and proposing directions for future research. Sorghum is basically composed of starch, which is more slowly digested than that of other cereals, has low digestibility proteins and unsaturated lipids, and is a source of some minerals and vitamins. Furthermore, most sorghum varieties are rich in phenolic compounds, especially 3-deoxyanthocyanidins and tannins. The results obtained in vitro and in animals have shown that phenolics compounds and fat soluble compounds (polycosanols) isolated from sorghum benefit the gut microbiota and parameters related to obesity, oxidative stress, inflammation, diabetes, dyslipidemia, cancer, and hypertension. The effects of whole sorghum and its fractions on human health need to be evaluated. In conclusion, sorghum is a source of nutrients and bioactive compounds, especially 3-deoxyanthocyanidins, tannins, and polycosanols, which beneficially modulate, in vitro and in animals, parameters related to noncommunicable diseases. Studies should be conducted to evaluate the effects of different processing on protein and starch digestibility of sorghum as well as on the profile and bioavailability of its bioactive compounds, especially 3-deoxyanthocyanidins and tannins. Furthermore, the benefits resulting from the interaction of bioactive compounds in sorghum and human microbiota should be studied.

Biochemical changes in phenols, flavonoids, tannins, vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties

OBJECTIVE

To investigate the changes in total phenols, flavonoids, tannins, vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties.

METHODS

The changes in total phenols, total flavonoids, tannins, phenolic acids compounds, flavonoid components, vitamin E, β-carotene and antioxidant activity during soaking of sorghum grains were determined.

RESULTS

Total phenols, total flavonoids, tannins, vitamin E, β-carotene and antioxidant activity in raw sorghum were ranged from 109.21 to 116.70, 45.91 to 54.69, 1.39 to 21.79 mg/100 g, 1.74 to 5.25, 0.54 to 1.19 mg/kg and 21.72% to 27.69% and 25.29% to 31.97%, respectively. The above measured compounds were significantly decreased after soaking. p-Hydroxybenzoic acid, vanillic acid, syringic acid and cinnamic acid represent the major phenolic acids in Dorado variety. While ferulic acid, p-coumaric acid, gallic acid and caffeic acid represent the major phenolic acids in Shandaweel-6. On the other hand, protocatechuic acid represents the major phenolic acids in Giza-15. Regarding flavonoids components, Dorado was the highest variety in kampferol and naringenin while Shandaweel-6 was the highest variety in luteolin, apigenin, hypersoid, quercetin and christen. Finally, Giza-15 was the highest variety in catechin. Phenolic acids, flavonoid compounds and antioxidant activities were decreased after soaking.

CONCLUSIONS

Sorghum varieties have moderate quantities from total phenols, total flavonoids, tannins, phenolic acids compounds, flavonoid components, vitamin E, β-carotene and antioxidant activity which decreased after soaking.

Chemical Composition and Antioxidant Activity of Seed oil of Two Algerian Date Palm Cultivars (Phoenix dactylifera)

The fatty acid composition of date seed oil from two different date palm ( Phoenix dactylifera L.) cultivars, locally known as Degla-Baïdha and Tafezouine, were investigated. GC analysis revealed the presence of five dominant fatty acids: oleic C18:1 (46.51; 39.15%), lauric C12:0 (22.1; 28.5%), myristic C14:0 (10.7; 11.4%), palmitic C16:0 (9.6; 8.7%) and linoleic C18:2 (6.9; 6.1%). The oils was characterised by a low content of tocopherols (0.53; 1.41 μg/g). The antioxidant activity of the oils was investigated using the DPPH•(1,1-di-phenyl-2-picryl-hydrazyl) scavenging assay. The oils had a weak bleaching effect on DPPH• free radicals. This study showed that the qualities of the tested oils are highly comparable with those of some commercial seed oils of other plants. Furthermore, a statistical analysis using the hierarchy ascendant classification method was conducted in order to highlight the similarities and/or the differences regarding the contents of the main fatty acids found in some common plants and in the five most famous cultivars of Phoenix dactylifera of south eastern Algeria (Tafezouine, Degla-Baïdha, Deglet-Nour, Ghars, Tamdjouhert).

In vitro starch digestion in sorghum flour from Algerian cultivars

This work aims to evaluate starch digestion in whole sorghum grains. Nine sorghum cultivars were sampled from the Sahara of Algeria. The structural characteristics of sorghum grains were measured. Total starch (TS) varied between 67.67% and 74.82%, digestible starch (DS) between 64.34% and 69.70%, and resistant starch (RS) ranged from 2.55% to 7.98%. The kinetic of starch digestion displayed first-order model. For all sorghum cultivars, starch were digested with different extents, DS at infinite time (D ∞) ranged from 52.58 to 102.13 g/100 g dry starch, while the hydrolysis index (HI) ranged from 41.55% to 76.93% and high average glycemic index (GIavg) ranged from 65.97 to 94.14. The results showed that there are differences in grain quality of Algerian sorghum cultivars. The starch fractions have acceptable nutritional value with good in vitro digestibility characteristics suitable for human health and nutrition.

Chemical Composition and Antioxidant Activity of the Essential Oil and Fatty Acids of the Flowers of Rhanterium Adpressum

The essential oil obtained by hydrodistillation of the flowers of Rhanterium adpressum Coss. & Durieu was analyzed using GC and GC-MS. The essential oil was very rich in monoterpene compounds. The major components identified were the monoterpene hydrocarbons: camphene (21.8%), myrcene (19.3%) and α-pinene (17.4%). Other compounds, including limonene, β-pinene and terpinol-4-ol, were present in low content (4–6%). The composition of the fatty acids in the lipid extract obtained from the flowers was also investigated by GC and GC-MS. The main fatty acids identified were palmitic (47.4%), oleic (12.9%) and stearic acids (10.6%). The total phenolic contents and the antioxidant activities were also evaluated for both extracts. The total phenolic contents were determined using the Folin-Ciocalteu reagent and the antioxidant activities were measured using three different assays: DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging activity, FRAP (ferric reducing antioxidant potential) and a molybdenum assay. As a result of these tests, the lipid extract exhibited the highest antioxidant activities in comparison with the essential oil extract.