Investigation of sprout-growth-inhibitory compounds in the volatile fraction of potato tubers

SummaryTotal sprout length and the length of the longest sprout were shown to be the most universally useful measurements to estimate sprout development in batches of potato tubers. A good estimate of sprout weight was also derived from measurements of total sprout length. There was a good linear relationship between total sprout length and initial tuber weight but the relationship varied considerably with the time of measurement and the temperature of storage.It is suggested that if sprout measurements are to be used to predict the field performance of a batch of tubers the changing pattern of sprout vigour with time needs to be more closely understood.

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Effect of Low Levels of Ethylene on Sprouting of Potatoes in Storage

HortScience ◽

10.21273/hortsci.39.1.136 ◽

2004 ◽

Vol 39 (1) ◽

pp. 136-137 ◽

Cited By ~ 10

Author(s):

R.B.H. Wills ◽

M.A. Warton ◽

J.K. Kim

Keyword(s):

Solanum Tuberosum ◽

Potato Tubers ◽

Ethylene Concentration ◽

Significant Difference ◽

Low Levels ◽

Sprout Growth

Potato tubers (Solanum tuberosum cv. Sebago) were stored at 20 °C in air containing ethylene at <0.005, 0.01, 0.1, 1.0, or 10 μL·L-1 and the level of sprouting was measured over 35 days. The time for tubers to develop an average of one sprout per tuber was found to linearly increase as the log10 ethylene concentration decreased with the effect present over the whole range of concentration. After 35 days of storage, the number of sprouts/tuber was inversely related to the ethylene concentration, but the weight of sprouts was only lower for tubers held in <0.005 μL·L-1 ethylene. The more numerous sprouts on tubers held in 10 μL·L-1 ethylene were short and thick, while the less numerous sprouts on tubers in 0.01-1.0 μL·L-1 were long, thin, and branched, and resulted in no significant difference in total sprout weight between these concentrations. Reducing the concentration of ethylene in the atmosphere around stored potatoes thus reduced sprouting, but levels <0.01 μL·L-1 are required to minimize both sprout emergence and sprout growth.

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Changes in respiratory metabolism during sprouting of aged seed-potato tubers

Canadian Journal of Botany ◽

10.1139/b90-208 ◽

1990 ◽

Vol 68 (8) ◽

pp. 1619-1626 ◽

Cited By ~ 5

Author(s):

Loretta J. Mikitzel ◽

N. Richard Knowles

Keyword(s):

Seed Potato ◽

Respiratory Activity ◽

Potato Tubers ◽

Alternative Respiration ◽

Fresh Weight ◽

Alternative Pathways ◽

Aged Seed ◽

Study Interval ◽

Young Tuber ◽

Sprout Growth

Seed-potato tubers stored for more than 8 months lose apical dominance and sprout with reduced vigor compared with younger tubers. To determine if age-reduced vigor is associated with less efficient respiratory activity, contributions of the different modes of respiration were measured in tissue from 7- and 19-month-old tubers at 6-day intervals over an 18-day sprouting period. Although respiration rate of tissue from the two tuber ages was equal at planting, it increased for both during sprouting, reaching a level 51% higher in tissue from old tubers by the end of the study. Tuber age and time had no effect on cytochrome-mediated respiration, which averaged 18 nmol O2/(min∙g fresh weight) over the study interval. However, the rate of alternative respiration of tissue from old tubers increased through day 12, reaching a level 30-fold greater than that of tissue from young tubers. As a percentage of total respiration, residual respiration was relatively constant (26%) in both ages of tissue during sprouting. In young tuber tissue, alternative respiration decreased from 9 to 1% of the total by day 12. Over the same period, the proportion of alternative respiration in old tissue increased from 14 to 28%, and this occurred with a concomitant decrease in the proportion of cytochrome-mediated respiration. During sprouting, old tubers appeared to be generating higher levels of ATP through a combination of the cytochrome-mediated and alternative pathways compared with young tubers; however, the increased energy-metabolizing ability of old seed tubers is less efficient at meeting the demands of sprout growth, as indicated by the lower weight of sprouts produced. Key words: potato, age-reduced vigor, respiration, sprouting.

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Tequila Agave Bagasse Hydrolysate for the Production of Polyhydroxybutyrate by Burkholderia sacchari

Bioengineering ◽

10.3390/bioengineering6040115 ◽

2019 ◽

Vol 6 (4) ◽

pp. 115 ◽

Cited By ~ 3

Author(s):

Yolanda González-García ◽

Janessa Grieve ◽

Juan Carlos Meza-Contreras ◽

Berenice Clifton-García ◽

José Antonio Silva-Guzman

Keyword(s):

Carbon Source ◽

Activated Charcoal ◽

Reducing Sugars ◽

Hydroxybutyric Acid ◽

Inhibitory Compounds ◽

Growth Inhibitory ◽

Biotechnological Processes ◽

Main Components ◽

Dry Cell ◽

By Products

Tequila agave bagasse (TAB) is the fibrous waste from the Tequila production process. It is generated in large amounts and its disposal is an environmental problem. Its use as a source of fermentable sugars for biotechnological processes is of interest; thus, it was investigated for the production of polyhydroxybutyrate (PHB) by the xylose-assimilating bacteria Burkholderia sacchari. First, it was chemically hydrolyzed, yielding 20.6 g·L−1 of reducing sugars, with xylose and glucose as the main components (7:3 ratio). Next, the effect of hydrolysis by-products on B. sacchari growth was evaluated. Phenolic compounds showed the highest toxicity (> 60% of growth inhibition). Then, detoxification methods (resins, activated charcoal, laccases) were tested to remove the growth inhibitory compounds from the TAB hydrolysate (TABH). The highest removal percentage (92%) was achieved using activated charcoal (50 g·L−1, pH 2, 4 h). Finally, detoxified TABH was used as the carbon source for the production of PHB in a two-step batch culture, reaching a biomass production of 11.3 g·L−1 and a PHB accumulation of 24 g PHB g−1 dry cell (after 122 h of culture). The polymer structure resulted in a homopolymer of 3-hydroxybutyric acid. It is concluded that the TAB could be hydrolyzed and valorized as a carbon source for producing PHB.

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Growth of wood-inhabiting yeasts of the Faroe Islands in the presence of spent sulphite liquor

Antonie van Leeuwenhoek ◽

10.1007/s10482-021-01543-5 ◽

2021 ◽

Author(s):

Jonas Rönnander ◽

Sandra Ann Ingela Wright

Keyword(s):

Paper Industry ◽

Waste Product ◽

Faroe Islands ◽

Industrial Chemicals ◽

Acid Hydrolysate ◽

Inhibitory Compounds ◽

Spent Sulphite Liquor ◽

Growth Inhibitory ◽

Decaying Wood ◽

Similar Growth

AbstractIn the microbial community of decaying wood, yeasts are important for the recycling of nutrients. Nevertheless, information on their biodiversity in this niche in the Northern hemisphere is limited. Wood-colonising yeasts encounter identical and similar growth-inhibitory compounds as those in spent sulphite liquor (SSL), an energy-rich, acid hydrolysate and waste product from the paper industry, which may render them well-suited for cultivation in SSL. In the present study, yeasts were isolated from decaying wood on the Faroe Islands and identified based on sequence homology of the ITS and D1/D2 regions. Among the yeasts isolated, Candida argentea, Cystofilobasidium infirmominiatum, Naganishia albidosimilis, Naganishia onofrii, Holtermanniella takashimae and Goffeauzyma gastrica were new to decaying wood in cold and temperate climates. C. argentea and Rhodotorula are rarely-isolated species, with no previous documentation from cold and maritime climates. The isolates were further tested for growth in a medium with increasing concentrations of softwood SSL. Most grew in the presence of 10% SSL. Isolates of Debaryomyces sp., C. argentea and Rhodotorula sp. were the most tolerant. Representatives of Debaryomyces and Rhodotorula have previously been found in decaying wood. In contrast, the least tolerant isolates belonged to species that are rarely reported from decaying wood. The relative importance of individual inhibitors to yeast growth is discussed. To our knowledge, none of the present yeast species have previously been cultivated in SSL medium. Decaying wood can be a useful future source of yeasts for valorisation of various hydrolysates to industrial chemicals and biofuels.

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The ftsH Gene of the Wine Bacterium Oenococcus oeni Is Involved in Protection against Environmental Stress

Applied and Environmental Microbiology ◽

10.1128/aem.69.5.2512-2520.2003 ◽

2003 ◽

Vol 69 (5) ◽

pp. 2512-2520 ◽

Cited By ~ 59

Author(s):

Jean-Paul Bourdineaud ◽

Benjamin Nehmé ◽

Sonia Tesse ◽

Aline Lonvaud-Funel

Keyword(s):

Protein Function ◽

Bradyrhizobium Japonicum ◽

Osmotic Shock ◽

Sequence Similarity ◽

Gene Expression Pattern ◽

Oenococcus Oeni ◽

Gene Encoding ◽

E Coli ◽

Inhibitory Compounds ◽

Growth Inhibitory

ABSTRACT The wine bacterium Oenococcus oeni has to cope with harsh environmental conditions, including an acidic pH, a high alcoholic content, nonoptimal growth temperatures, and growth-inhibitory compounds such as fatty acids, phenolic acids, and tannins. We describe the characterization and cloning of the O. oeni ftsH gene, encoding a protease belonging to the ATP binding cassette protein superfamily. The O. oeni FtsH protein is closest in sequence similarity to the FtsH homologue of Lactococcus lactis. The O. oeni ftsH gene proved to be stress-responsive, since its expression increased at high temperatures or under osmotic shock. O. oeni FtsH protein function was tested in an Escherichia coli ftsH mutant strain, and consistent with the O. oeni ftsH gene expression pattern, the O. oeni FtsH protein provided protection for the E. coli ftsH mutant against heat shock. O. oeni and Bradyrhizobium japonicum FtsH proteins also triggered E. coli resistance to wine toxicity. Genes homologous to O. oeni ftsH were detected in many other lactic acid bacteria found in wine, suggesting that this type of gene constitutes a well-conserved stress-protective molecular device.

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Evaluating Ecologically Acceptable Sprout Suppressants for Enhancing Dormancy and Potato Storability: A Review

Plants ◽

10.3390/plants10112307 ◽

2021 ◽

Vol 10 (11) ◽

pp. 2307

Author(s):

Nyasha Gumbo ◽

Lembe Samukelo Magwaza ◽

Nomali Ziphorah Ngobese

Keyword(s):

Tuber Quality ◽

Rapid Decline ◽

Potato Tubers ◽

Weight Changes ◽

Postharvest Storage ◽

Sprout Suppression ◽

Tuber Sprouting ◽

Sprout Growth ◽

Sprout Suppressants

Postharvest losses are a key stumbling block to long-term postharvest storage of potato tubers. Due to the high costs and lack of infrastructure associated with cold storage, this storage method is often not the most viable option. Hence, sprout suppressants are an appealing option. In most developing countries, potato tubers in postharvest storage are accompanied by a rapid decline in the potato tuber quality due to the physiological process of sprouting. It results in weight changes, increased respiration, and decreased nutritional quality. Therefore, proper management of sprouting is critical in potato storage. To avoid tuber sprouting, increased storage and transportation of potatoes demands either the retention of their dormant state or the application of sprout growth suppressants. This review evaluates the current understanding of the efficacy of different sprout suppressants on potato storability and the extension of potato shelf-life. We also consider the implications of varied study parameters, i.e., cultivar, temperature, and method of application, on the outcomes of sprout suppressant efficacies and how these limit the integration of efficient sprout suppression protocols.

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