Experimentation of a Forced Convection Solar Dryer for Drying Sweet Potatoes at the Higher Institute of Technology of Mamou-Guinea

This study was carried out at the Mamou Higher Institute of Technology during the period from March 10 to April 15, 2022, with the aim of designing and testing a solar dryer with forced convection by drying potatoes. The dryer was designed using local materials. Its main geometric parameters are: 1) height of the drying chamber (90 cm), 2) length of the drying chamber (50 cm), 3) width of the drying chamber (43 cm), 4) surface of the racks (0.1806 m2), 5) surface of the heat accumulator (0.2537 m2). The experiment focused on the vacuum test of the dryer for two days and that of the drying of the sweet potato for three days from 8:30 a.m. to 5:30 p.m. The average vacuum test temperature values of the three environments are respectively accumulator (43°C), dryer chamber (41°C) and ambient environment (34°C). Four kilograms (4 kg) of boiled sweet potato were dried. The average temperatures in the accumulator and in the drying chamber during the three days of drying are respectively 33°C and 39°C. The final mass of the dried product is 1.2 kg, with a quantity of water extracted of 2 liters or 63% of the initial mass of the product. The average drying rate is 0.074 kg/h. The drying kinetics showed a decreasing rate in the absence of the heating period and the constant rate period.

Extraction Characteristics of Anthocyanins from Preliminarily-processed Products of Purple Sweet Potatoes during the Gelatinization Process

Objective] This study aimed to investigate the method for efficient utilization and development of purple sweet potatoes. [Method] Purple sweet potatoes were dried at two specific temperatures and prepared into preliminarily-processed products for gelatinization simulation to analyze the extraction amount of anthocyanins from gelatinized samples at different gelatinization stages. [Result] During the gelatinization process, the extraction rate of anthocyanins from purple sweet potato samples reached the highest as the temperature rised from 90 ℃ to 95 ℃,and the extraction amount of anthocyanins reached the maximum at 15 min postheat preservation at 95 ℃. Purple sweet potato samples dried at 60 ℃ exhibited larger retention amount, larger maximum extraction amount and higher maximum extraction rate of anthocyanins compared with those dried at 110 ℃. [Conclusion] Drying at low temperatures and appropriately shortening the initial gelatinization stage below 90 ℃ is conducive to the retention and extraction of anthocyanins from purple sweet potatoes.

Hot Potatoes在外语教学中的应用

Hot Potatoes软件具有简便易用的特点,有助于辅助缺乏计算机技术基础的外语教师制作多种形式的网页式习题。在计算机辅助外语教学中应用Hot Potatoes能够帮助学生整合课堂与课外学习,巩固课堂所学并开展自主学习,同时还能够帮助学生适应新的四六级网考评估模式。

Metabolic profiles and morphological characteristics of leaf tips among different sweet potato(Ipomoea batatas Lam.)varieties

Sweet potato leaf tips have high nutritional value,and exploring the differences in the metabolic profiles of leaf tips among different sweet potato varieties can provide information to improve their qualities.In this study,a UPLC-Q-Exactive Orbitrap/MS-based untargeted metabolomics method was used to evaluate the metabolites in leaf tips of 32 sweet potato varieties.Three varieties with distinct overall metabolic profiles(A01,A02,and A03),two varieties with distinct profiles of phenolic acids(A20 and A18),and three varieties with distinct profiles of flavonoids(A05,A12,and A16)were identified.In addition,a total of 163 and 29 differentially expressed metabolites correlated with the color and leaf shape of sweet potato leaf tips,respectively,were identified through morphological characterization.Group comparison analysis of the phenotypic traits and a metabolite-phenotypic trait correlation analysis indicated that the color differences of sweet potato leaf tips were markedly associated with flavonoids.Also,the level of polyphenols was correlated with the leaf shape of sweet potato leaf tips,with lobed leaf types having higher levels of polyphenols than the entire leaf types.The findings on the metabolic profiles and differentially expressed metabolites associated with the morphology of sweet potato leaf tips can provide useful information for breeding sweet potato varieties with higher nutritional value.

Highβ-sitosterol-D-glucoside content in sweet potato varieties and its anti-breast cancer potential through multiple metastasis-associated signals

β-Sitosterol-D-glucoside(β-SDG)is a phytosterol compound whose antitumor activity has been confirmed by previous studies.However,its suppression on breast cancer remains unclear.To that purpose,we isolatedβ-SDG from sweet potato and investigated the breast-cancer-inhibiting mechanism using proteomic analysis.The sweet potato species S6 with highβ-SDG content were chosen form 36 species andβ-SDG was isolated by HPLC.Afterwards,an in situ animal model of breast cancer was established,andβ-SDG significantly reduced the tumor volume of MCF-7 xenograft mice.Proteomic analysis of tumor tissues revealed that 127 of these proteins were upregulated and 80 were downregulated.Gene ontology and network analysis showed that regulatory proteins were mainly associated with epithelial-mesenchymal transition(EMT),myogenesis,cholesterol homeostasis,oxidative phosphorylation and reactive oxygen pathways,while Vimentin,NDUF,VDAC1,PPP2CA and SNx9 were the most significant 5 node degree genes.Meanwhile,in vitro and in vivo results showed that the protein expression of PPP2CA and Vimentin,which are markers of EMT,were involved in breast cancer cell metastasis and could be reversed byβ-SDG.This work highlightsβ-SDG as a bioactive compound in sweet potato and the potential therapeutic effect ofβ-SDG for the treatment of breast cancer by inhibiting metastasis.

Effect of Inorganic and Organic Fertilizers on Growth and Yield of Two Industrial Potato Varieties (Asterix and Courage) in Bangladesh

Potato is one of the most important vegetable crops, which contributes more than half of the total vegetable production in Bangladesh. Four field experiments were conducted in two different locations in Bangladesh to develop integrated nutrient management practices to produce quality potato seed in industrial processing varieties Asterix and Courage. For the inorganic trial, Factorial Randomized Complete Block Design (RCBD) including 2 potato varieties, 5 treatments with 4 replications, and in the organic fertilizer trial, Factorial RCBD including 2 potato varieties, 6 treatments with 4 replications were used. In the inorganic fertilizer trail, the highest yield was obtained in the variety Asterix due to Nitrogen, Phosphorus, Potassium, and Sulfur (NPKS) plus Magnesium treated plot in Domar BADC farm and due to NPKS plus Boron, Zinc, and Magnesium treated plots in Kashimpur Farm. In the case of variety Courage, the highest yield was found in the treatment of NPKS plus Zinc in Domar BADC farm while in Kashimpur farm, NPKS plus Mg treated plots had the highest yield of potato variety-Courage. In the organic fertilizer trail, the highest tuber yield per hill was obtained by applying the government-approved commercial brand Northern organic fertilizer in variety Asterix and by organic fertilizer brand Chook Chook in variety Courage. Parameters such as days to tuber initiation, number of stems per hill, plant height, and number of tubers per hill were found statistically different among the treatments and between the two varieties. Treatments namely Northern organic fertilizer and Cowdung combined with mustard oil cake performed better considering standard grade tuber yield (grade A and B) compared to other treatments. Hence, the combination of NPKS MgZn and either Northern organic or Chook Chook or Cowdung plus mustard oil cake could be used to grow the varieties Asterix and Courage.

Development and Validation of Integrated Nutrient Management Practices of Industrial Processing Varieties: Asterix and Courage in Bangladesh

An experiment was meticulously conducted at the research field of Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur, Bangladesh, during the 2011-2012 potato growing season to develop integrated crop management practices for the potato seed production of industrial processing varieties Asterix and Courage. Significantly, higher growth and yield parameters were found in the BADC-recommended practice. Later, another experiment was conducted to validate the BADC practice during the 2013-2014 potato growing season in two locations in Bangladesh. Results showed that the production of tuber per hill, tuber weight per hill as well as gross tuber yield per plot, higher proportion of storable seed tubers, and more quality seed potatoes (A-grade and B-grade) seed tubers were found significantly higher in the “BADC developed practice” compared to other treatments. Viral diseases (PLRV and PVY) prevalence was lower in “BADC developed practice”. Moreover, “BADC developed practice” contributed more economic yield by minimizing input cost compared to “Munshiganj advanced farmers’ practice”. Therefore, the “BADC developed practice” was found “superior” regarding yield, quality, and profitability in seed potato production of industrial varieties—Asterix and Courage in Bangladesh.

Hot Potatoes在英语练习与测试中的应用

本文介绍了web交互式练习题软件Hot Potatoes及其主要功能特点,然后详细介绍了使用Hot Potatoes制作英语单项选择题、阅读理解题的方法,以及如何通过The masher把各种类型的题目组合起来。

Hot Potatoes交互式网络教学软件的应用

Hot Potatoes是专门用来制作互动式测验练习的软件,它无需编程,只要输入文本便可以制作出Web页面的交互式测验练习,适用于学生自学及练习之用.本文作者根据个人在制作Hot Potatoes课件的实践经验,介绍该交互式练习软件的特性、制作及其应用.

Influence of Sanitization Process on Maintaining Sweet Potato Quality for Export

The whole cold-chain for exporting sweet potato(native variety“Abees”),to foreign market included immediate curing operation directly after harvest helped in healing skin texture,however,in order to reduce postharvest soft rot(Rhizopus stolonifer)incidence following trimming,and washing,ultraviolet light(UV-C)treatment was used as a main sanitizer for eliminating the soft rot.Exposure of the roots to UV-C(254 nm)was applied in a UV-C room on freshly harvested and cured sweet potato while rolling up on a movable line at 20 cm distance for 1,2,and 3 hr.As combining UV-C treatment with chlorine(200 ppm)on roots,marked and significant reduction of the total microbial load and Rhizopus potential was achieved on root surfaces respectively compared with chlorine alone.It also reduced soft rot percentage to almost 0%infection.After 3 months of cold-storage,quality assessment of sweet potato showed that root characteristics were markedly maintained.The ability of UV-C light to induce phenylalanine ammonia lyase(PAL)enzyme activity in root tissue and maintain the activities of peroxidase and polyphenol oxidase,however with slight increase,was detected.UV-C caused an increase of phenol content in sweet potato tissue that made an activation of defense reaction against the rot causal pathogen.As the exposure time to UV-C light increased,a higher content of phenols occurred.Moreover,UV-C application caused decrease in sugar content of root tissue that is flavored by soft rot-causal pathogen.

Determination of Trace Elements in Potatoes by Flame Atomic Absorption Spectrometry

[Objective] This study aimed to analyze the contents of trace elements in potatoes from different production areas in Qinghai Province. [Method] By flame atomic absorption spectrometry （FAAS）, the contents of various trace elements in potatoes were determined. [Result] Potatoes contain abundant trace elements such as Cu, Zn, Fe, Mn, Ca, K and Mg. To be specific, the contents of Ca, K and Mg were relatively high. [Conclusion] By using FAAS, the relative standard deviation was 1.17%-2.75% and the recovery rate was 97%-99.5%, indicating accurate and reli-able results with high precision.

利用Hot Potatoes轻松制作英语网考模拟题

新的教学模式以现代信息技术为支撑,特别是网络技术,使英语教学朝着个性化学习、不受时间和地点限制的学习、主动式学习方向发展。通过使用Hot Potatoes制作英语听力选择题和复合式听写、阅读理解题的方法,能够帮助学生适应新的四六级网考评估模式。

Targeting Cancers: Uncovering the Potential Roles of Potato Tissue Culture as Anti-Cancer Agents - A Secondary Publication

Plant tissue culture is a technique that enhances the quality and quantity of potatoes. Potatoes are a significant crop and are primarily used in the world. It is a staple food in many countries, where millions of tonnes are produced annually. It is an essential source of many nutrients, such as proteins, carbohydrates, vitamins, and beta-carotene. In addition, potatoes are being used as therapeutic agents against cancer and other human diseases as well. Potatoes are on the third list after wheat and rice. To overcome food shortages and malnutrition, there are two methods used for producing potatoes: the first is sexual, which is seed propagation, and the second is asexual, which is plant tissue culture propagation. Conventional potato breeding is a uniform method, but it is unsafe because there is a risk of pathogen attack. In a laboratory setting, the tissue culture of potatoes produced millions of plants with nutrient-rich medium under controlled environmental conditions that prevent pest attacks. Some environmental stresses, such as salinity and water scarcity, affect potato yield and production;however, applying nanoparticles like organic, inorganic, and silicon dioxide enhances potato quality and combats stress. Biotechnology has proven to be helpful in addressing all these issues. This review discusses the significance of potatoes, their production through the tissue culture technique, and the application of nanoparticles to improve the growth, and impact of potatoes on human health.

Effect of Size and Initial Water Content on the Effective Diffusion Coefficient during Convective Drying of Sweet Potato Cut into Cubic and Cylindrical Shapes

In this article, we investigated the influence of size and initial water content on the effective diffusion coefficient of sweet potatoes samples cut into cubic and cylindrical shapes. The sizes of the cubic samples are 0.5, 1, 1.5, 1.75, 2, 2.5 and 3 cm edge with a respective initial water content of 2.7, 3.76, 3.48, 2.68, 3.28, 2.17 and 2.29 kg/kgms. For cylindrical samples, the radius is set at 0.5 cm and sample heights are 1, 1.5, 2, 2.5, 3, 3.5 and 4 cm with respective water contents of 2.2, 3.19, 2.85, 2.1, 2.17, 2.39 and 2.03 kg/kgms. The effective diffusion coefficients of cubic samples are of the order of 10−10 and 10−9 m2∙s−1 grew with sample edge. As for the cylindrical samples, the effective diffusion coefficients were of the order of 10−9 m2∙s−1 and there was no linear correlation between cylinder height and their effective diffusion coefficient. As for the examination of the initial water content on the effective diffusion coefficient, it turned out that the initial water content had no influence on the effective diffusion coefficient of the sweet potato samples.

Nutritional evaluation of different cultivars of potatoes(Solanum tuberosum L.) from China by grey relational analysis(GRA) and its application in potato steamed bread making

Chemical composition(moisture,protein,starch,ash,fiber,fat),vitamins(vitamin C,vitamin B1,vitamin B2),total polyphenol content,antioxidant capacity,minerals,and amino acid of 14 potato cultivars in China were evaluated.The results indicated that all parameters varied significantly among different potato cultivars.The total starch,crude protein and fat content ranged between 57.42–67.83%,10.88–14.10% and 0.10–0.73% dry weight(DW),respectively.Moreover,the consumption of potato increased remarkably the dietary intake of vitamins,K,Mn and Cu.In addition,the chemical score of amino acid varied considerably between different cultivars,which ranged from 54(Neida 3 and Neida 41) to 71(Neida 34).Grey relational analysis(GRA) indicated that Neida 26 exhibited the most comprehensive nutritional values among potato cultivars,followed by Neida 42.Different potato flours had a significant effect on the quality parameters of potato steamed bread(PSB),Neida 26 and Neida 34 were more suitable for making PSB.

Inhibitory effect of tartary buckwheat seedling extracts and associated flavonoid compounds on the polyphenol oxidase activity in potatoes(Solanum tuberosum L.)

To improve the processing quality of potatoes,phosphate buffer extract(PBE),50%ethanol(E50),and aqueous extract(AE)of tartary buckwheat seedlings were evaluated for their ability to inhibit the enzymatic browning of potatoes.The results suggest that all extracts of tartary buckwheat seedlings exert significant inhibitory effects on the polyphenol oxidase(PPO)activity in potatoes.The relative concentrations required for a 50%reduction in the PPO activity(IC50)were 0.21,0.28 and 0.41 mg mL^-1,for PBE,E50 and AE,respectively.The strongest inhibitory activity was observed for PBE,followed by E50 and AE.Four flavone compounds in the PBE of tartary buckwheat seedlings(i.e.,rutin,kaempferol-3-O-rutinoside,quercetin,and kaempferol)were identified by high-performance liquid chromatography.These compounds were subsequently evaluated for their roles in the inhibition of PPO from potatoes using a model system.The results indicated that rutin exhibited the highest inhibition rate on the PPO of potato.A synergistic inhibitory effect was observed by mixing rutin,kaempferol-3-Orutinoside,quercetin,and proteins.The inhibitory patterns of rutin,kaempferol-3-O-rutinoside,and quercetin on the enzyme were noncompetitive and reversible,with inhibitory constants of 0.12,0.31,and 0.40 mg mL^-1,respectively.Flavonoids from tartary buckwheat seedlings may exhibit a common mechanism with phenolic compounds,involving the blockage of the reaction of oxygen with PPO leading to the inhibition of the enzymes involved in browning.Based on these results,extracts of tartary buckwheat seedlings can be used as potent natural inhibitors.

Effects of Drying Processes on the Antioxidant Properties in Sweet Potatoes

The effects of different drying methods （hot-air drying, microwave drying and vacuum-freeze drying） on the antioxidant activity and antioxidants in sweet potato （lpomoea batatas L. Lain.） tubers were investigated to determine the potential drying process. Sweet potato tubers were cut into 5 mm thick slices, steamed at 100℃ for 10 rain, then dried in either hotair, microwave, or vacuum-freeze. The dried sweet potatoes in microwave possessed the highest antioxidant activity, while the lowest activity was observed in hot-air dried samples. The phenolic contents were positively correlated with scavenging activity and reducing power of DPPH^＋. The microwave drying retains the highest antioxidant activity with the highest content of phenolic compounds in dried sweet potatoes. β-carotene and ascorbic acid showed minor contribution to the antioxidant activity in dried sweet potatoes.

Nitrogen Nutrition Index and Its Relationship with N Use Efficiency, Tuber Yield, Radiation Use Effi ciency, and Leaf Parameters in Potatoes

Knowledge about crop growth processes in relation to N limitation is necessary to optimize N management in farming system. Plant-based diagnostic method, for instance nitrogen nutrition index （NNI） were used to determine the crop nitrogen status. This study determines the relationship of NNI with agronomic nitrogen use efficiency （AEN）, tuber yield, radiation use efficiency （RUE） and leaf parameters including leaf area index （LAI）, areal leaf N content （NJ and leaf N concentration （N0. Potatoes were grown in field at three N levels： no N （N 1）, 150 kg N ha^-1 （N2）, 300 kg N ha^-1 （N3）. N deficiency was quantified by NNI and RUE was generally calculated by estimating of the light absorbance on leaf area. NNI was used to evaluate the N effect on tuber yield, RUE, LAI, NAL, and NL. The results showed that NNI was negatively correlated with AEN, N deficiencies （NNI〈 1） which occurred for N 1 and N2 significantly reduced LAI, NL and tuber yield; whereas the N deficiencies had a relative small effect on NAL and RUE. To remove any effect other than N on these parameters, the actual ratio to maximum values were calculated for each developmental linear relationships were obtained between NNI and tuber RUE to NNI. stage of potatoes. When the NNI ranged from 0.4 to 1, positive yield, LAI, NL, while a nonlinear regression fitted the response of

Influences of Different Distances between Ridges or Plants on Yield of Sweet Potatoes

Based on the combination test of various distances between ridges or plants, the influences of corresponding cultivation techniques on the per unit area yield of a variety of sweet potatoes Xushu 22 in Xianning City were analyzed. The results show that different distances between ridges or plants had significant effects on the per unit area yield of Xushu 22; when the distances between ridges and plants for Xushu 22 planted in the city were 80 and 21 cm respectively, the per u- nit area yield of Xushu 22 was the highest, up to 48 340.7 kg/hm2.

Sensory Evaluation of Pigmented Flesh Potatoes (<i>Solanum tuberosum</i>L.)

Pigmented potato cultivars were ranked by a consumer panel for overall acceptance, and acceptance of aroma, appearance, and flavor. Potatoes were analyzed for total phenolics, anthocyanins and carotenoids. Concentrations of total phenolics in yellow and purple potato cultivars were 2-fold greater (P P