Phytic acid is the principal storage form of phosphorus in plant seeds and an essential signalling molecule in several regulatory processes of plant development.However,it is known as an anti-nutrient compound owing t...Phytic acid is the principal storage form of phosphorus in plant seeds and an essential signalling molecule in several regulatory processes of plant development.However,it is known as an anti-nutrient compound owing to its potent chelating property.Thus,reducing the phytic acid content in crops is desirable.Studies involving regulation of MIPS and IPK1 genes to generate low phytate rice have been reported earlier.However,the functional significance of OsITPK and the effect of its down-regulation on phytic acid content and the associated pleiotropic effects on rice have not yet been investigated.In this study,tissue specific RNA interference(RNAi)-mediated down-regulation of a major ITPK homolog(OsITP5/6K-1)resulted in 46.2%decrease in phytic acid content of T2 transgenic seeds with a subsequent 3-fold enhancement in the inorganic phosphorus content.Silencing of OsITP5/6K-1 altered the transcript levels of essential phytic acid pathway genes,without significantly affecting the transcript levels of other OsITPK homologs.Furthermore,the mapping of elements through X-ray microfluorescence analysis revealed significant changes in the spatial distribution pattern and translocation of elements in low phytate seeds.Additionally,low phytate polished seeds exhibited 1.3-fold and 1.6-fold enhancement in iron and zinc content in the grain endosperm,respectively.Silencing of OsITP5/6K-1 also altered the amino acid and myo-inositol content of the transgenic seeds.Our results successfully established that RNAi-mediated silencing of OsITP5/6K-1 gene significantly reduced the phytate levels in seeds without hampering the germination potential of seeds and plant growth.The present study provided an insight into the mechanism of phytic acid biosynthesis pathway.展开更多
This study gives an overview on the nutritional value, bioactive compounds and antioxidant activity (ABTS and FRAP) of Bronte’s pistachio (Pistacia vera, L., cv. Bianca) from Sicily (Italy). Bronte’s pistachios are ...This study gives an overview on the nutritional value, bioactive compounds and antioxidant activity (ABTS and FRAP) of Bronte’s pistachio (Pistacia vera, L., cv. Bianca) from Sicily (Italy). Bronte’s pistachios are rich in fat, protein, dietary fiber, trace elements (Fe, Zn, Cu, Mn) and minerals (Ca, P, K, Mg, Na). Lipids mainly consist of MUFA (33.8 g/100g), primarily oleic acid (32.4 g/ 100g);PUFA is mostly represented by linoleic acid (7.49 g/100g). Bronte’s pistachios are also a valuable source of bioactive compounds such as total polyphenols (501.5 mg/100g), lutein (1.26 mg/100g), β-carotene (0.18 mg/100g), γ-tocopherol (19.2 mg/100g) and phytosterols (134.4 mg/100g). Among phytosterols, the main is β-sitosterol (86% of total content), followed by Δ5-avenasterol (6.3%). Phytic acid content is 1763 mg/100g;Ins(1,2,4,5,6)P5 and Ins(1,2,3,4,5,)P5 have been detected too (31 mg/100g and 10 mg/100g, respectively). The antioxidant activity was determined both in hydrophilic and lipophilic fraction of pistachios, showing >80% of the total antioxidant activity in the hydrophilic, predominately due to phenolic compounds.展开更多
A procedure for preparing of inositol triphosphate from sodium phytate was established.Hydrolysis was achieved by microwave rediation.When The hydrolysis rate of phytic acid was about 50%,the hydrolyzed solutions were...A procedure for preparing of inositol triphosphate from sodium phytate was established.Hydrolysis was achieved by microwave rediation.When The hydrolysis rate of phytic acid was about 50%,the hydrolyzed solutions were pumped into a column containing 717 strong anion-exchange resin,then delivered a linear gradient of 0.05～0.7MNaCl.the samples of each tube were digested and the phosphate was determined.the contents of tubes corre-sponding to the same individual inositol phosphate were pooled together,and precipitated by Ca2+.The cacium salt was then turned into IP3.Neutralized with sodium bydroxide,rotary evaporated under vaccum,lyophilized,the desired product was gotten.Each inositol phosphate was identified by HPLC and MS.展开更多
文摘Phytic acid is the principal storage form of phosphorus in plant seeds and an essential signalling molecule in several regulatory processes of plant development.However,it is known as an anti-nutrient compound owing to its potent chelating property.Thus,reducing the phytic acid content in crops is desirable.Studies involving regulation of MIPS and IPK1 genes to generate low phytate rice have been reported earlier.However,the functional significance of OsITPK and the effect of its down-regulation on phytic acid content and the associated pleiotropic effects on rice have not yet been investigated.In this study,tissue specific RNA interference(RNAi)-mediated down-regulation of a major ITPK homolog(OsITP5/6K-1)resulted in 46.2%decrease in phytic acid content of T2 transgenic seeds with a subsequent 3-fold enhancement in the inorganic phosphorus content.Silencing of OsITP5/6K-1 altered the transcript levels of essential phytic acid pathway genes,without significantly affecting the transcript levels of other OsITPK homologs.Furthermore,the mapping of elements through X-ray microfluorescence analysis revealed significant changes in the spatial distribution pattern and translocation of elements in low phytate seeds.Additionally,low phytate polished seeds exhibited 1.3-fold and 1.6-fold enhancement in iron and zinc content in the grain endosperm,respectively.Silencing of OsITP5/6K-1 also altered the amino acid and myo-inositol content of the transgenic seeds.Our results successfully established that RNAi-mediated silencing of OsITP5/6K-1 gene significantly reduced the phytate levels in seeds without hampering the germination potential of seeds and plant growth.The present study provided an insight into the mechanism of phytic acid biosynthesis pathway.
文摘This study gives an overview on the nutritional value, bioactive compounds and antioxidant activity (ABTS and FRAP) of Bronte’s pistachio (Pistacia vera, L., cv. Bianca) from Sicily (Italy). Bronte’s pistachios are rich in fat, protein, dietary fiber, trace elements (Fe, Zn, Cu, Mn) and minerals (Ca, P, K, Mg, Na). Lipids mainly consist of MUFA (33.8 g/100g), primarily oleic acid (32.4 g/ 100g);PUFA is mostly represented by linoleic acid (7.49 g/100g). Bronte’s pistachios are also a valuable source of bioactive compounds such as total polyphenols (501.5 mg/100g), lutein (1.26 mg/100g), β-carotene (0.18 mg/100g), γ-tocopherol (19.2 mg/100g) and phytosterols (134.4 mg/100g). Among phytosterols, the main is β-sitosterol (86% of total content), followed by Δ5-avenasterol (6.3%). Phytic acid content is 1763 mg/100g;Ins(1,2,4,5,6)P5 and Ins(1,2,3,4,5,)P5 have been detected too (31 mg/100g and 10 mg/100g, respectively). The antioxidant activity was determined both in hydrophilic and lipophilic fraction of pistachios, showing >80% of the total antioxidant activity in the hydrophilic, predominately due to phenolic compounds.
文摘A procedure for preparing of inositol triphosphate from sodium phytate was established.Hydrolysis was achieved by microwave rediation.When The hydrolysis rate of phytic acid was about 50%,the hydrolyzed solutions were pumped into a column containing 717 strong anion-exchange resin,then delivered a linear gradient of 0.05～0.7MNaCl.the samples of each tube were digested and the phosphate was determined.the contents of tubes corre-sponding to the same individual inositol phosphate were pooled together,and precipitated by Ca2+.The cacium salt was then turned into IP3.Neutralized with sodium bydroxide,rotary evaporated under vaccum,lyophilized,the desired product was gotten.Each inositol phosphate was identified by HPLC and MS.
