Characterization of Soluble Sugar Content, Related Enzyme Activity and Gene Expression in the Fruits of ‘Minihyang’ Mandarin on Different Rootstocks

‘Minihyang’ mandarin bears fruits with small size and high sugar content. ‘Minihyang’ mandarin grafted on trifoliate orange (TO) tends to be vigorous and develops water sprout open. It is associated with insufficient floral differentiation and fruit set. Recently, the use of Flying Dragon (FD) as rootstock with a high dwarf effect has been proposed to improve this situation. Therefore, this study was conducted to evaluate the effect of two different rootstock genotypes on tree growth, fruit yield, and fruit quality at the physiological, biochemical, and molecular levels. As a result of the study, in FD, tree vigor was stably maintained, fruit size was large, and the sugar content was high compared to the TO. Fructose, glucose, and sucrose of fruit continued to increase from development to maturity. In particular, fructose and sucrose were significantly higher in the fruits of the FD than those in TO at 150 and 220 days after anthesis. The total sugar content was also significantly higher in the fruit of the FD. The activities of SPS and SS associated with sucrose synthesis tended to be increased during the fruit maturity season, but there was no significant difference between the two rootstocks. On the other hand, the activities of SS and AI breaking down sucrose were high in FD at 150 and 220 days after anthesis. These results suggest that the unloading of sucrose might be increased and affect the sugar content. However, the results of real-time PCR analysis of gene expression related to sucrose metabolism did not show an association with changes in enzyme activity affecting sugar content. Therefore, further detailed studies on the process after the regulation of gene expression are likely to be needed.

Metabolic Variation among Fruits of Different Chili Cultivars (Capsicum spp.) Using HPLC/MS

Chilies are widely cultivated for their rich metabolic content, especially capsaicinoids. In our study, we determined individual sugars, organic acids, capsaicinoids, and total phenolic content in pericarp, placenta, and seeds of Capsicum annuum L., Capsicum chinense Jacq. and Capsicum baccatum L. by HPLC/MS. Dry weight varied in the cultivar ‘Cayenne’, with the first fruit having the lowest dry weight, with 4.14 g. The total sugar content and organic acid content did not vary among the fruits of all three cultivars. The cultivar ‘Cayenne’ showed differences in total phenolic and capsaicinoid content between fruits in the placenta, with the first fruit having the highest content of total phenolics (27.85 g GAE/kg DW) and total capsaicinoids (16.15 g/kg DW). Of the three cultivars studied, the cultivar ‘Habanero Orange’ showed the least variability among fruits in terms of metabolites. The content of dihydrocapsaicin, nordihydrocapsaicin, homocapsaicin, and homodihydrocapsaicin in the seeds of the second fruit was higher than that of the first fruit of the cultivar ‘Bishop Crown’. The results of our study provided significant insight into the metabolomics of individual fruits of the same chili plant. We have thus increased our understanding of how certain metabolites are distributed between fruits at different levels of the same plant and different parts of the fruit. This could be further investigated when chilies are exposed to different environmental stresses.

Assessment of the Antimicrobial and Fertilizing Activity of Table Olive Concentrated Waste Streams During Their Shelf Life

Table olive wastewaters represent a big problem for factories not yet solved. Some partial solutions are the purification, the reuse or the generation of a smaller volume of these liquids. The purpose of this study was to investigate the possibility of obtaining a concentrate that can be stable over time and that has a biofertilizing capacity on tomato (Solanum lycopersicum L.) plants. In this study, washing waters from Spanish style green and storage liquids from black ripe olive processing were vacuum concentrated up to 10, 13 and 17 times so that they reached total sugar content of up to 700 mmol L−1, 925 mmol L−1 and 1200 mmol L−1 respectively. Interestingly, the evaporation achieved to retain most of the phenolic compounds that ranged from 18 mmol L−1 in the fresh solution to 140 mmol L−1 in the solution concentrated 10 times. Moreover, these concentrates showed in vitro antimicrobial activity against the bacteria Erwinia amylovora and Pseudomonas syringae, and the Oomycota Phytophthora sp. In addition, they increased the strength and cumulative yield of the tomato plants cultivated under greenhouse conditions, even after 12 months of storage at room temperature. It has been demonstrated that it is possible to reduce the large volume of the wastewaters of the table olive industry, and the concentrates have potential application for agricultural uses, even after 1 year of storage, thereby contributing to a more environmentally sustainable industry. Graphical Abstract

Optimized Degradation and Inhibition of α-glucosidase Activity by Gracilaria lemaneiformis Polysaccharide and Its Production In Vitro

Gracilaria lemaneiformis polysaccharide (GLP) exhibits good physiological activities, and it is more beneficial as it is degraded. After its degradation by hydrogen peroxide combined with vitamin C (H2O2-Vc) and optimized by Box–Behnken Design (BBD), a new product of GLP-HV will be generated. While using GLP as control, two products of GLP-H (H2O2-treated) and GLP-V (Vc-treated) were also produced. These products chemical characteristics (total sugar content, molecular weight, monosaccharide composition, UV spectrum, morphological structure, and hypolipidemic activity in vitro) were assessed. The results showed that the optimal conditions for H2O2-Vc degradation were as follows: H2O2-Vc concentration was 18.7 mM, reaction time was 0.5 h, and reaction temperature was 56 °C. The total sugar content of GLP and its degradation products (GLP-HV, GLP-H and GLP-V) were more than 97%, and their monosaccharides are mainly glucose and galactose. The SEM analysis demonstrated that H2O2-Vc made the structure loose and broken. Moreover, GLP, GLP-HV, GLP-H, and GLP-V had significantly inhibition effect on α-glucosidase, and their IC50 value were 3.957, 0.265, 1.651, and 1.923 mg/mL, respectively. GLP-HV had the best inhibition effect on α-glucosidase in a dose-dependent manner, which was the mixed type of competitive and non-competitive. It had a certain quenching effect on fluorescence of α-glucosidase, which may be dynamic quenching.

Effects of Genetic Background and Altitude on Sugars, Malic Acid and Ascorbic Acid in Fruits of Wild and Cultivated Apples (Malus sp.)

Soluble sugars, malic acid, and ascorbic acid in 17 apple cultivars (Malus domestica Borkh.) and three wild forms (M. pumila ‘Saiwaihong’, M. prunifolia (Willd.) Borkh. and M. micromalus Makino) from three major apple cultivation regions in China were quantified using gas chromatography equipped with flame ionization detector (GC-FID). Fructose was the most abundant sugar, followed by sucrose, glucose, and sorbitol. Wild apples contain more sorbitol and less sucrose and were significantly more acidic than cultivated fruits. The total sugar content varied from 110 to 160 mg/g fresh fruits, total acid content from 2 to 6 mg/g, with a strong influence of genetic background and growth location. Overall, ‘Gala’, ‘Xiali’, ‘Liuyuehong’, ‘Lihong’, ‘Starking Delicious’, and ‘Starkrimson’ were characterized by higher sugar/acid ratio indicating sweeter taste compared to other cultivars. The wild apples had the highest content of ascorbic acid (0.6–0.96 mg/g). Compared to other cultivars, ‘Zhongqiuwang’, ‘Qinguan’, and ‘Nagafu No. 2′ were richer in ascorbic acid. The ascorbic acid content in the commercial cultivars was highly dependent on growth location. The content of malic acid and sucrose positively correlated to altitude, and that of glucose negatively. Malic acid positively correlated with ascorbic acid and sucrose, glucose content with ascorbic acid.

Utilization of Banana Peel Flour in Biscuit Making as Wheat Flour Substitute

The production of biscuits utilizing ripe banana peel flour (BPF) as a wheat flour (WF) alternative is presented in this study. Locally available Sabri banana peel was dried into a cabinet dryer at 65⁰C for 8 hours. The dried peel then turned into powder and sieved. The flours used in the preparation of the biscuits were analyzed for proximate composition. BPF contained a higher amount of fat compared to WF. Five samples of biscuits S1, S2, S3, S4, and S5 substituting WF with 0, 5, 10, 20, and 30% BPF in the standard biscuits were prepared S1 denoted the control sample adding no BPF. The proximate composition and sensory quality of the produced biscuits were tested. All of the biscuit samples had greater weights than the control biscuit. In comparison to the control biscuit, BPF enriched biscuits had reduced diameter. Biscuits made with 10% BPF had a greater spread ratio than those made with other ingredients. The moisture, protein, fat, and total sugar content of biscuit samples were found in the range of 4.05-5.32%, 6.60-9.00%, 10.00-10.32%, and 17.00-25.00%, respectively. A sharp decrease in protein content was observed with the increase of BPF in the biscuits. A slight increase of fat was observed in the BPF substituted biscuits. The ash content in the control sample was 1.5%, and that in the banana peel substituted samples ranged from 1.80% to 2.0%. BPF substitution showed a downward trend in terms of color, flavor, texture, and general acceptability. The panelists rated sample S1 as having the highest overall acceptability. Among the BPF-containing biscuits, sample S2 had the best overall acceptance, followed by samples S3, S4, and S5. In terms of general acceptability, however, there are no notable variations between samples S2 and S3. According to sensory analysis, quality BPF biscuits may be prepared by replacing up to 10% of the WF with BPF.

The Sharp Rise in the Use of Low- and No-Calorie Sweeteners in Non-Alcoholic Beverages in Slovenia: An Update Based on 2020 Data

Reducing added sugars in non-alcoholic beverages is an important public health goal, which can result in increased use of low- and no-calorie sweeteners (LNCS). The aim of this study was to investigate recent changes in the use of LNCS in non-alcoholic beverages in the Slovenian food supply. The national branded foods dataset was updated with beverages available in 2020, and compared with previous datasets. The data were extracted from food labels. In 2020, N = 1,650 unique beverages were found in shops from five different retailers, covering the majority of the national market. The use of LNCS increased from 13.2% in 2017 and 15.5% in 2019 to 20.2% in 2020, with a major growth in soft drinks (16.8, 19.6, and 26.7%, respectively). We observed a significant growth of beverages containing both LNCS and added sugar. Results were also consistent with sales data, which showed that increased offer of beverages with LNCS also resulted in similarly increased sales of such beverages. The average energy and total sugar content in non-alcoholic beverages decreased, which reflects both the higher percentage of beverages with LNCS, and also the reduction of the sugar content in beverages with only added sugar. Analyses of product-specific reformulation practices highlighted reduced sugar content in 16.8% of products, and in 3.6% with the use of LNCS. The most commonly used LNCS are acesulfame K, sucralose, and aspartame. Typically, combinations are used, however steviol glycosides, sucralose and saccharin are also used alone, in most cases combined with added sugar. The results indicated rapid changes in the use of LNCS in non-alcoholic beverages in the Slovenian food supply, making further monitoring of this area highly relevant.

The relationship between the chemical composition and taste of strawberries

The results of the evaluation of promising 24 cultivars and 6 forms of garden strawberries by their chemical composition (contents of ascorbic acid, titrated acid, sugars, dry substances, monosaccharides, the level of the sugar-acid coefficient) and the taste qualities of the fruits are presented to identify sources of high taste qualities and high content of biologically active substances. Seven cultivars and forms (Aidarina, Assol, Zarina, Efsane 3-15 Atlantida × Uniol, 12-15 Sunrise × Hercules, 25-15 Jantarnaja × Zenga Zengana) with a high fruit flavor (4.8-5.0 points); six cultivars (Aidarina, Assol, Atlantida, Bagryana, Zarina, Present) with an increased content of ascorbic acid (76.1-85.4 mg/100 g); eight cultivars and forms (Bagryana, Hercules, Krymskaya Remontantnaya, Luiza, Sanika, Honey, 3-15 Atlantida × Uniol, 14-15 Sunrise × Clery) with high titratable acidity (1.1-1.2%); five cultivars (Aidarina, Albion, Bagryana, Zarina, Rusanovka) with optimal total sugar content (7.5-9.8%); four cultivars (Albion, Bagryana, Krymskaya Remontantnaya, Uniol) with a high amount of dry matter (10.6-17.3 %); seven cultivars and forms (Assol, Albion, Zarina, Krymskaya Rannaya, Rusanovka, 13-15 Sunrise × Zenga Zengana, 14-15 Sunrise × Clery, 25-15 Jantarnaja × Zenga Zengana) with a high sugar-acid index (8.0-11.9). The lowest variability (8.2-16.7%) was characterized by such signs as the taste of fruits and the content of total sugar, titrated acidity, and the highest (18.3-25.0%) - the content of ascorbic acid, solids, and the sugar-acid index. The most significant correlation between the sugar-acid coefficient and the biochemical parameters of strawberry fruits was revealed.

Investigation of the efficiency of beet syrup usage in products based on nutraceutical principles

The nature of nutrition is the most important factor determining human health. Proper healthy nutrition maintains health, plays an important role in preventing chronic diseases in modern humans. The level of food product quality must meet the human physiological needs for nutrients and energy, and healthy nutrition also includes the concept of the preventive effect of food, or food as a risk factor for chronic non-communicable diseases. When nutrients are in improper proportions, nutrition is considered incorrect, unhealthy, irrational, and may play a role as a risk factor for the development of human diseases. The paper substantiates the use of beet syrup and beet in ketchup technology and the benefits of the developed recipes for human health. It also covers the physicochemical composition of beet syrup, which contains 93.5% dry matter, and sugar composition and content in beet syrup: glucose, fructose, sucrose, and maltose, the total sugar content is 48.8 g/100 g that is 50.2 g/100 g less than common sugar. The ratio of prescription ingredients, established by experimental investigations on organoleptic parameters, is substantiated. The water activity index was investigated, which constituted 0.92 in the second sample, 0.93 – in the first sample, and 0.93 – in the control sample, which will have a positive effect on their shelf life. The examination of the chemical composition showed that the protein content in the first sample increased by 33%, in the second sample – by 56% compared to the control sample; the sugar content reduced by 42.7% in the first sample and by 50.6% in the second sample; the vitamin C content increased; the fiber content increased 3 times; the developed products are enriched with iron, phosphorus, and potassium. The Nutri-score calculation showed that the samples developed according to formulas №1 and №2 belong to categories A and B and are more balanced and beneficial to human health, which indicates the high nutritional value of the products. In terms of the energy value, the developed samples have an advantage over the control. The energy value (kcal/100 g) of the first sample is 100, the second sample – 89.5, and the control sample – 104.