Kinds Of Free Amino Acids Research Articles

Elucidation of potential relationship between endogenous proteases and key flavor substances in dry-cured pork coppa

Dry-cured meat products are considerably popular around the world due to unique flavor. Proteolysis is one of the enzymatic reactions from which flavor substances are derived, which is affected by endogenous proteases. The purpose aimed to reveal the potential relationship between endogenous proteases and key flavor substances in dry-cured pork coppa in this paper. The dynamic changes of endogenous proteases activity, free amino acids, and volatiles during dry-cured pork coppa processing were characterized. The results showed that 5 kinds of free amino acids, Glu, Lys, Val, Ala, and Leu, were identified as significant contributors to taste. Meanwhile, key volatiles, such as hexanal, nonanal, octanal, benzaldehyde, 3-methyl butanoic acid, 2-methyl propanoic acid, and ethyl octanoate, greatly contributed to the flavor characteristics of dry-cured pork coppa. Further partial correlation analysis was performed to better elucidate the relationship among parameters. The results revealed that close relationship between endogenous proteases and key substances. RAP not only significantly affected the accumulation of key active-amino acids, but also affected the accumulation of ethyl octanoate, 2,3-pentanedione, and 2,3-octanedione by regulating the accumulation of octanoic acid and Leu. In addition, cathepsin B and D, DPP Ⅱ, DPP Ⅳ and RAP notably affected accumulation of hexanal.

Different characteristics of 40 kinds of free amino acids and 5-amino levulinic acid between wines and sakes (Japanese rice wines)

Based on a systemic analysis for the global burden of disease study from 1990 to 2016, the Global Burden of Diseases (GBD) 2016 Alcohol Collaborators reported that alcohol use was a leading risk factor for global disease burden and caused substantial health loss. However, alcoholic drink (wines and sakes) contains abundant nutrients, particularly fermentable amino acids derived from grapes and rice. Amino acid nutrition and metabolism is strongly associated with health and prevention against various diseases. The purpose of this study was to elucidate 40 kinds of free amino acid (FAA) profiles in wines and sakes. In addition, the present study also provided the contents of 5-aminolevulinic acid (5-ALA) involved in the vital functionality of mitochondria. FAAs were detected and analyzed by use of an automatic amino acid analyzer. Aromatic amino acid, branched chain amino acid and Fischer ratio were calculated for each beverage. Individual FAAs showed significant differences between wines and sakes. Sakes abundantly contained almost all FAAs whereas wines had just a little content in some FAAs. Sake were rich in arginine, glycine, alanine, valine, glutamic acid and leucine, while wines were remarkably rich in proline (Pro). Wines showed increased FAA levels in 6 kinds of variables (4-hydroxyproline, 3-methyl histidine, β-alanine, α-aminobutyric acid, Pro and α-aminoadipic acid). In functionally characteristic FAAs, both wines and sakes were considerably abundant in γ-aminobutyric acid and 5-ALA. The total amount of aromatic amino acid and branched chain amino acid were markedly higher in sakes than in wines. These results revealed that there were the apparent different characteristics in FAA profiles between wines and sakes. This difference resulted from fermentation process in wines (single fermentation) and sakes (parallel double fermentation). Forty kinds of FAA profiles are more useful in investigating characteristics of the taste of wines and sakes. In future, detailed FAA analysis has the potential to find functional nutrients such as 5-ALA, whereas other foods generally contain little amount of these FAAs.

Properties investigations of rape stalks fermented by different salt concentration: Effect of volatile compounds and physicochemical indexes.

In order to find out the effect of salt concentration on fermented rape stalks, the physicochemical quality and volatile components was investigated using high performance liquid chromatography (HPLC) and headspace solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS). The results showed that there were abundant kinds of free amino acids (FAAs) in all samples, mainly presenting sweet, umami and bitter taste. Through taste activity value (TAV), His, Glu, and Ala contributed significantly to the taste of the sample. 51 volatile components were identified, of which the relative contents of ketones and alcohols were high. By the relative odor activity value (ROAV) analysis, the main components that had a great impact on the flavor were phenylacetaldehyde, β-Ionone, ethyl palmitate and furanone. Adjusting the appropriate salt concentration for fermentation could improve the comprehensive quality of fermented rape stalks and promote the development and utilization of rape products.

Effects of microbial community structure and its co-occurrence on the dynamic changes of physicochemical properties and free amino acids in the Cantonese soy sauce fermentation process

The soy sauce produced by Cantonese fermentation has a unique flavor, among which brine fermentation plays an important role. In this fermentation process, 61 volatile compounds, including 19 esters, 10 aldehydes, 9 alcohols, 5 phenols, and 18 others, were identified by headspace solid-phase microextraction–gas chromatography–mass spectrometry. Seventeen kinds of free amino acids were detected by high-performance liquid chromatography. Results showed that Touyou, which comprised 1.5 g/100 g total nitrogen, 1.0 g/100 mL amino acid nitrogen, 3.66 g/100 g reducing sugar, 1.44 g/100 mL total acid, 17.04 g/100 mL salt content, and 27.3% umami free amino acids, had excellent quality. High-throughput sequencing was used to identify microorganisms. The top 3 of bacteria were Weissella, Staphylococcus, and Lactobacillus, and the top 3 fungi were Aspergillus, Zygosaccharomyces, and Candida. The co-occurrence network analysis of microorganisms showed that the top-ranked microorganisms were Plectosphaerella, Aureobasidium, unidentified_Mortierellales_sp, Glutinomyces, Faecalibacterium, and Cladophialophora. Then, eight microorganisms (VIP[pred] > 1) were obtained by two-way orthogonal partial least squares model, namely, Staphylococcus, Candida, Weissella, Aspergillus, Zygosaccharomyces, Lactobacillus, Monilinia, and Clavispora. Correlation analysis showed that these microorganisms were strongly related to flavor metabolites. This study explored the dynamics of traditional Cantonese fermentation, which has positive implications for optimizing this traditional fermentation process.

Combination of Glycinamide and Ascorbic Acid Synergistically Promotes Collagen Production and Wound Healing in Human Dermal Fibroblasts.

The purpose of this study is to present a novel strategy to enhance collagen production in cells. To identify amino acid analogs with excellent collagen production-enhancing effects, human dermal fibroblasts (HDFs) were treated with 20 kinds of amidated amino acids and 20 kinds of free amino acids, individually at 1 mM. The results showed that glycinamide enhanced collagen production (secreted collagen level) most effectively. Glycine also enhanced collagen production to a lesser degree. However, other glycine derivatives, such as N-acetyl glycine, N-acetyl glycinamide, glycine methyl ester, glycine ethyl ester, and glycyl glycine, did not show such effects. Glycinamide increased type I and III collagen protein levels without affecting COL1A1 and COL3A1 mRNA levels, whereas transforming growth factor-β1 (TGF-β1, 10 ng mL−1) increased both mRNA and protein levels of collagens. Ascorbic acid (AA, 1 mM) increased COL1A1 and COL3A1 mRNA and collagen I protein levels. Unlike TGF-β1, AA and glycinamide did not increase the protein level of α-smooth muscle actin, a marker of differentiation of fibroblasts into myofibroblasts. The combination of AA and glycinamide synergistically enhanced collagen production and wound closure in HDFs to a level similar to that in cells treated with TGF-β1. AA derivatives, such as magnesium ascorbyl 3-phosphate (MAP), 3-O-ethyl ascorbic acid, ascorbyl 2-O-glucoside, and ascorbyl tetraisopalmitate, enhanced collagen production, and the mRNA and protein levels of collagens at 1 mM, and their effects were further enhanced when co-treated with glycinamide. Among AA derivatives, MAP had a similar effect to AA in enhancing wound closure, and its effect was further enhanced by glycinamide. Other AA derivatives had different effects on wound closure. This study provides a new strategy to enhance cell collagen production and wound healing using glycinamide in combination with AA.

The key enzymes and flavor precursors involved in formation of characteristic flavor compounds of low-salt fermented common carp (Cyprinus carpio L.)

Unique flavor is the key quality of fermented fish. In this study, the precursors and key enzymes related to the flavor of Suanyu were analyzed. The results showed that 17 kinds of free amino acids and 22 kinds of free fatty acids were detected during the fermentation. According to variable importance for predictive components values (VIP), amino acids including aspartate, phenylalanine, methionine, glutamic acid, leucine, valine, isoleucine, cysteine and fatty acids including C16:0, C20:5, C20:4, C18:1, C22:6, C18:0 and C16:1 were screened as key precursors affecting the characteristic flavor of Suanyu. Moreover, the changes of enzyme activities in different metabolic processes of flavor were determined. Phosphofructokinase (PFK), pyruvate kinase (PK), lipoxygenase (LOX), hydroperoxidase lyase (HPL) and alcohol acyltransferase (AAT) activities reached the maximum in the first week of fermentation. However, hexokinase (HK), branched chain amino acid transferase (BCAT), aromatic amino acid transferase (ARAT) and esterase activities significantly decreased with the fermentation. Furthermore, ARAT, HPL, esterase, BCAT, AAT and HK were screened as the key enzymes that affected the characteristic flavor of Suanyu. All these results indicated that the control of key flavor precursors and enzymes during fermentation was a potential method to improve the flavor of fermented fish.

Effect of infection by Beauveria bassiana on hemolymph and free amino acid in Xylotrechus rusticus

AbstractThe purpose of this study was to clarify changes in the immune response of the hemolymph after infection with Beauveria bassiana in Xylotrechus rusticus larvae in order to reveal the physiological regulating mechanism of the pathogenic fungi. The results showed that B. bassiana was infectious to X. rusticus adults. The main infection sites were the thoracic internodes, lower wings, and abdomen. After infection with B. bassiana, the number of blood cells in the X. rusticus larvae was significantly higher than the control. The number of plasma cells and granulocytes in the hemolymph of the insect was largest. The total number of blood cells was mainly affected by the changes in number of plasma cells and granulocytes. The trehalose content in X. rusticus larvae after B. bassiana treatment continued to decrease compared to the control. The glucose content in the larvae hemolymph increased first, then decreased. The acid trehalase activity was significantly higher than the control, and the high activity was maintained for 60–84 h after infection with B. bassiana. Nineteen kinds of free amino acids were detected in the larvae hemolymph infected by B. bassiana. After infection, the total amount of free amino acids in the larvae hemolymph presented a trend where the amount first declined, then rose. Proline, arginine, and glutamine were the main amino acids required for the growth and development of B. bassiana in X. rusticus larvae. The amount of hemolymph and free amino acids played an important role in immunity during the infection with B. bassiana.

Analysis of the basic components and free amino acid composition of pineapple fruit vinegar

Acetic acid fermentation is an essential step in producing high-quality vinegar. In this study, the alcoholic medium was used as a seed broth for acetic fermentation using Acetobacter aceti as the inoculum for approximately 7 days at 32℃ to obtain 45.87g/L acetic acid. During the Acetic acid fermentation stage, the content of the total polyphenols decreased first and then increased. Based on amino acid analyzer analysis, pineapple vinegar contains 18 kinds of free amino acids. And the contents of sweet and umami free amino acids are the main free amino acids, followed by bitter amino acids.

Detection and analysis of free amino acids in waxy maize DH lines by HPLC in north-east China

Composition of free amino acid in waxy maize DH lines was analysed and the nutritional quality of waxy maize germplasm resources was evaluated by o-phthaladehyde (OPA) pre-column derivatization reversed-phase high performance liquid chromatography (HPLC). Results obtained showed that there were at least 14 kinds of free amino acids, DH57 line had the highest (25.185 mg/g), and DH21 line had the lowest (6.203 mg/g) and the average was 12.226 mg/g. The contents of essential amino acids varied from 2.59 to 14.09 mg/g, accounting for 29.55 - 75.64% of the total free amino acids. The quality of free amino acids was evaluated by comprehensive indices with principal component analysis and the first top three DH lines were DH57, DH59 and DH55. The contents of free amino acids in 60 waxy maize DH lines had obvious genetic diversity. As to the free amino acid content, the amino acids quality of DH57, DH59 and DH55 were the best, while DH21 was the worst. Results provide a theoretical guidance for the cultivation of new varieties of waxy maize with good quality.

Chemical Composition, Antioxidant and Antihyperglycemic Activities of the Wild Lactarius deliciosus from China.

The wild mushroom Lactarius deliciosus from China was studied for the first time to obtain information about its chemical composition, antioxidant, and antihyperglycemic activities. Nutritional value, dietary fiber, fatty acids, metal elements, free sugars, free amino acids, organic acids, flavor 5′-nucleotides, and volatile aroma compounds were determined. Potential antioxidant and antihyperglycemic activities were also tested by investigating 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals scavenging activities, ferric ion reducing activity, as well as α-amylase and α-glucosidase inhibitory activities using ethanol and aqueous extracts. The results showed that L. deliciosus was a good wild mushroom with high protein, carbohydrate, and dietary fiber contents, while low in fat and calorie, extensive unsaturated fatty acids contents, with negligible health risks about harmful metal elements. Twenty kinds of free amino acids were detected with a total content 3389.45 mg per 100 g dw. Flavor 5′-nucleotides including 5′-CMP, 5′-UMP, 5′-IMP, and 5′-AMP were 929.85, 45.21, 311.75, and 14.49 mg per 100 g dw, respectively. Mannitol (7825.00 mg per 100 g dw) was the main free sugar, and quininic acid (729.84 mg per 100 g dw) was the main organic acid. Twenty-five kinds of volatile aroma compounds were identified, acids (84.23%) were the most abundant compounds based on content, while aldehydes (15 of 25) were the most abundant compounds based on variety. In addition, both ethanol and aqueous extracts from L. deliciosus exhibited excellent antioxidant activity. While in antihyperglycemic activity tests, only ethanol extracts showed inhibitory effects on α-amylase and α-glucosidase.

Changes in pericarp metabolite profiling of four litchi cultivars during browning

The pericarp browning is an important physiological index during the postharvest storage, which seriously shortens the shelf-life of litchi fruit. In this study, the browning index of four litchi cultivars were compared, and the shelf-life, from longer to shorter, was ‘Feizixiao (FXZ)’, ‘Jingganghongnuo (JGHN)’, ‘Huaizhi (HZ)’ and ‘Nuomici (NMC)’, respectively. Then, comparative metabolomics were performed in the pericarp of four litchi cultivars during browning. Finding results showed that a total of 119 kinds of metabolites were detected in litchi pericarp, including 30 kinds of primary metabolites, 44 kinds of volatile compounds, 29 kinds of free amino acids and 16 kinds of hydrolytic amino acids. After ANOVA and OPLS-DA, 52 kinds of metabolites were important with predictive VIP > 1 and p < 0.05. In FZX pericarp, the contents of many amino acids increased significantly, which might be related to the yellow-green pericarp and play an important role in delaying browning. In the pericarp of JGHN, NMC and HZ, a great number of soluble sugars and some free amino acids were induced during browning, which was negatively correlated with the browning speed of three red pericarp cultivars. The browning induced a large number of sesquiterpenes in the pericarp of FZX, NMC and HZ, which was positively correlated with the browning index. In addition, the correlation analysis showed that the amino acids were negatively correlated with the volatile compounds, suggesting that pericarp browning could induce the conversion of metabolic products from amino acids to terpenes.

Aspergillus oryzae와 단백질 분해효소 첨가에 따른 콩알메주 된장의 이화학적 특성 변화

The purpose of this study was to investigate the physiochemical properties of Doenjang was fermented by added with fungi and protease. The moisture content and pH of Doenjang added with protease (WP) were lower than those of control w/o protease while the contents of titratable acidity, reducing sugar, and amino-type nitrogen in WP were higher than control. The α-amylase activities of Doenjang added with single and mixed Protease B were the highest at 4 weeks of fermentation period and protease activity of WP was about 4 times higher than that of control. The 4-9 kinds of free amino acids (proline, isoleucine, leucine, and phenylalanine etc.) in WP was increased in comparison with control. The DPPH radical scavenging activity and total polyphenol content were higher in WP than control. Total aerobic bacterial and fungal numbers were decreased depending on fermentation time regardless of addition of protease. In conclusion, the protease can be used as additives improving the quality and taste of fermented Doenjang.

Effect of Different Ratio of Cake Fertilizer and Inorganic Fertilizer on Free-amino Acids in Burley Leaves

A Reversed-Phase High Performance Liquid Chromatographic method was developed for determining free Amino Acids in Burley Tobacco. The test was done by OPA/3-mercaptopropionic Acid as the pre-column derivatising reagent. Chromatographic column was Elitte C18 column (4.6 mm×250 mm i.d., 5 um). Mobile phase A was 18 mol/L NaAc (PH7.2) including 0.002% (v/v) trimethylamine and 0.3% (v/v) furanidine. Mobile phase B was 100 mol/L NaAc (PH7.2) -Acetonitrile-methanol (v/v = 1:2:2). The column temperature was 40°C and the flow rate was 1.0 mL/min. The fluorescence detector was used with 350 nm excitation wave length and 450 nm emission wave length. The average recoveries of the method ranged 95.3 to 100.7% with the relative standard deviation of 2.32~9.24%. The method is simple, accurate and has good repeatability. The results of the determination of seventeen kinds of free Amino Acids in burley leaves which were produced by way of different ratio of cake fertilizer and inorganic fertilizer. The results show that Aspartic acid has the highest content however ratio of cake fertilizer and inorganic fertilizer. The contents most of free Amino Acids are increased and then gradually decreased with the increase of organic manure. The contents most of free Amino Acids are very close at 15:85% ratio and 30:70% ratio of cake fertilizer and inorganic fertilizer. The total amount of free Amino Acids is the highest at 30:70% ratio of cake fertilizer and inorganic fertilizer. Considering comprehensively, the quality of burley leaves is the best at 30:70% ratio of cake fertilizer and inorganic fertilizer.

Determination of free amino acids in burley tobacco by high performance liquid chromatography

A reversed-phase high performance liquid chromatographic method was developed for determining free amino acids in burley tobacco. The test was done by OPA/3-mercaptopropionic acid as the pre-column derivatizing reagent. Chromatographic column was Elitte C18 column (4.6mm×250mm i.d., 5μm). Mobile phase A was 18mol/l NaAc (pH7.2) including 0.002%(v/v) triethylamine and 0.3%(v/v) furanidine. Mobile phase B was 100mol/l NaAc (pH7.2)–acetonitrile–methanol (v/v=1:2:2). The column temperature was 40°C and the flow rate was 1.0ml/min. The fluorescence detector was used with 350nm excitation wave length and 450nm emission wave length. The average recoveries of the method ranged from 95.3–100.7% with the relative standard deviation of 2.32–9.24%. The method is simple, accurate and has good repeatability. The results of the determination of seventeen kinds of free amino acids in burley leaves were produced by the way of different ratios of cake fertilizer and inorganic fertilizer. The results show that Aspartic acid has the highest content however ratio of cake fertilizer and inorganic fertilizer. The contents of most of the free amino acids are increased and then gradually decreased with the increase in organic manure. The contents of most of the free amino acids are very close at 15:85% ratio and 30:70% ratio of cake fertilizer and inorganic fertilizer. The total amount of free amino acids is the highest at 30:70% ratio of cake fertilizer and inorganic fertilizer. Considering comprehensively, the quality of burley leaves is the best at 30:70% ratio of cake fertilizer and inorganic fertilizer.

Bacillus subtilis 균주로 발효한 죽순발효액의 품질특성

To make fermented bamboo shoot liquid, we isolated and classified a microorganism growing in bamboo shoot and investigated its quality characteristics. Crude fiber, crude ash, nitrogen-free extracts, and total sugar contents were higher after fermentation. For free amino acids, only alanine was detected in the control group. Detected 13 kinds of free amino acids were detected in fermented bamboo shoot liquid. In organoleptic test, fermented bamboo shoot beverage containing 20 percent strawberry showed the highest consumer preference.

Comparative Analysis of Amino Acid Composition in Antarctic Krill and White Shrimp

The purpose of this experiment is to evaluate the nutritional value of amino acids and its commercial value in the fish processing sector in Antarctic krill with cross-referenced in the white shrimp. For determination of the composition of 17 amino acids in the two shrimp muscle, free amino acids were measured using sulfosalicylic acid method, hydrolysed amino acid using hydrochloric acid hydrolysis.17 kinds of hydrolysed amino acids are measured in the muscle of Antarctic krill and White shrimp, which total content is 513.59±18.56mg/g and 537.61±16.8mg/g respectively.16 kinds of free amino acids are measured, which total content is 616.88±44.61mg/100g and 1276±75.67mg/100g respectively, while cysteine is not found. According to amino acid score (AAS), chemical score (CS), the limiting amino acid of Antarctic krill and White shrimp is valine and methionine + cysteine. The umani amino acids accounted for 27.76% of free amino acids and 35.69% of hydrolysed amino acids in Antarctic krill, while White shrimp is 41.08% and 31.52% respectively. The amino acids in Antarctic krill, TAV of which is greater than 1, include glutamic acid, alanine, lysine and arginine.

흑마늘 첨가에 따른 청국장의 항산화 및 아미노산의 변화

의성흑마늘영농조합법인The antioxidant activity and amino acid composition of various Cheonggukjang extracts, such as the water extract from Cheonggukjang (CWE), the alcohol extract from Cheonggukjang (CEE), the water extract from Cheonggukjang with black garlic (BWE) and the alcohol extract from Cheonggukjang with black garlic (BEE), were examined to investigate the effect of black garlic on the sensory quality and functional properties of Cheonggukjang. The total polyphenol contents of various extracts were 7.03 mg/100 g (BWE), 3.64 mg/100 g (CWE), 2.88 mg/100 g (BEE) and 0.81 mg/100 g (CEE). The radical scavenging activity of the DPPH radical was highest in BWE (91.83%), followed by BEE (37.35%), CWE (25.54%) and CEE (14.80%), in that order. The SOD-like activity was highest in BWE (20.20%), followed by BEE (9.22%), CWE (7.91%) and CEE (6.45%). The thiobarbituric acid reactive substances (TBARS) were highest in BWE (35.18%), followed by BEE (28.33%), CWE (17.40%) and CEE ((14.93%). The total amino acid content of Cheonggukjang (CC) was higher than that of Cheonggukjang with black garlic (CCWB), but the essential amino acid content of CCWB (43.18%) was higher than that of CC (42.27%). The 27 kinds of free amino acid were found in CC, but only 23 kinds were found in CCWB. The L-lysine content was highest (9.23%) in CC, and the L-phenylalanine content was highest (23.14%) in CCWB. The free amino acids (L-threonine, L-serine, L-sarcosine, L-proline, L-alanine, L-valine and D,L-β-aminoisobutyric acid) were found in CC but not in CCWB. The γ-amino-n-butyric acid (GABA) was found in CCWB but not in CC. These results suggest that the addition of black garlic has beneficial effects on the functionality of Cheonggukjang without decreasing its sensory characteristics.Key wordsgarlic, Cheonggukjang, antioxidant, amino acid

국내산과 미국산 블루베리의 이화학적 품질특성

경북대학교 식품외식산업학과 We investigated the quality characteristics of the Korean and American blueberry. There was a similarity between the general composition and sugar content of the Korean and American values. The pH values showed a low of 3.46 in American blueberries to a high of 4.49 in Korean blueberries. The L (lightness), a (redness), and b (yellowness) value scores of the American blueberry were higher than the Korean blueberry. The levels of total phenol content and DPPH radical scavenging abilities were 205 mg%, 93.48% in the Korean blueberry and 182 mg%, 84.32% in the American blueberry, respectively. The free sugar levels showed fructose 2,514 mg%, glucose 2,315 mg%, and sucrose 69 mg% in the Korean blueberry, while the free sugar levels of the American blueberry showed fructose 2,106 mg%, glucose 1,825 mg%. The contents of organic acid were lactic acid and tartaric acid in the Korean blueberry, while the organic acid in the American blueberry contained tartaric acid, succinic acid, oxalic acid, and lactic acid. The Korean blueberry has 12 kinds of free amino acids, while the American blueberry has 9 kinds of free amino acids. Furthermore, the Korean blueberry contains 390 mg% of total amino acids, which was higher than 32% in the American blueberry with 295 mg% of total amino acids. The fatty acid contents of the American blueberry (2,897 mg%) was higher than that of the Korean blueberry (2,783 mg%) as well as in the oleic acid, linoleic acid, and palmitic acid. The mineral contents of all the samples were P>K>Ca>Mg, respectively. Given the above results, the Korean blueberry bioactive chemicals or properties were thought to be somewhat higher than the American blueberry. Key wordsblueberry, quality characteristics, total phenol, DPPH radical scavenging

Nutritional Attributes and Health Application of Seabuckthorn (Hippophae rhamnoides L.) – A Review

Seabuckthorn is a rich source of nutrients and bioactive components beneficial for human health. Fruit juice is rich in sugar, organic acids, amino acids, essential fatty acids, phytosterol, flavonoids, vitamins and mineral elements. There are 24 minerals and 18 kinds of free amino acids in seabuckthorn juice. The total quantity of phytosterol in seabuckhtorn exceeds soybean oil by 4-20 times. Seabuckthorn seed is a source of valuable oil characterized by high oleic acid content and one to one ratio of omega-3 and omega-6 fatty acids. The oil absorbs ultraviolet light and promotes healthy skin. The leaves contain many nutrients and bioactive substances such as carotenoids, free and esterified sterols, triterpenols, and isoprenols. Seabuckthorn has been used in traditional system of medicine for centuries. Beneficial effects of seabuckthorn on human health have been extensively investigated and substantiated by studies, suggesting a great potential of the plant for maintaining and promoting human health. Recent research has supported and extended the traditional uses of the plant for treatment of various diseases. The unique and valuable characteristics of seabuckthorn shrub serve as a storehouse for researchers in the field of biotechnology, nutraceutical, pharmaceutical, cosmetic and environmental sciences. Traditional usage coupled with commercial value and modern scientific research has immense scope to benefit the modern society from the lesser known shrub.

Suppression of glutamate synthase genes significantly affects carbon and nitrogen metabolism in rice (Oryza sativa L.)

Rice (Oryza sativa) glutamate synthase (GOGAT, EC 1.4.1.14) enzymes have been proposed to have great potential for improving nitrogen use efficiency, but their functions in vivo and their effects on carbon and nitrogen metabolism have not been systematically explored. In this research, we analyzed transcriptional profiles of rice GOGAT genes using a genome-wide microarray database, and investigated the effects of suppression of glutamate synthase genes on carbon and nitrogen metabolism using GOGAT co-suppressed rice plants. Transcriptional profiles showed that rice GOGAT genes were expressed differently in various tissues and organs, which suggested that they have different roles in vivo. Compared with the wild-type, tiller number, total shoot dry weight, and yield of GOGAT co-suppressed plants were significantly decreased. Physiological and biochemical studies showed that the contents of nitrate, several kinds of free amino acids, chlorophyll, sugars, sugar phosphates, and pyridine nucleotides were significantly decreased in leaves of GOGAT co-suppressed plants, but the contents of free ammonium, 2-oxoglutarate, and isocitrate in leaves were increased. We conclude that GOGATs play essential roles in carbon and nitrogen metabolism, and that they are indispensable for efficient nitrogen assimilation in rice.