scholarly journals Bioconversion of potato solid waste into antifungals and biopigments using Streptomyces spp.

PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0252113
Author(s):  
Heidi Schalchli ◽  
Emilio Hormazábal ◽  
Álvaro Astudillo ◽  
Gabriela Briceño ◽  
Olga Rubilar ◽  
...  

Potato waste was processed and used as a sole substrate for simultaneously producing antifungals and biopigments using Streptomyces spp. Out of three different Streptomyces isolates, strain SO6 stood out due to its ability to produce antifungals against economically important fungal phytopathogens and intracellular biopigments using potato waste powders without additional nutrients. This strain also showed the potential to secrete a broad range of enzymes for fermentation of eight sugars that could be involved in potato waste bioconversion. The results of the fermentation assay indicated that Streptomyces sp. strain SO6 degrades potato wastes during submerged fermentation, diminishing total dry weight and increasing reducing sugars from 0.3 to 3.6 mg·mL−1 and total proteins from 70.6 to 187.7 μg·mL−1. The results showed that Streptomyces strain SO6 was able to convert the potato waste into 0.96 mg·g−1 of diffusible antifungals and 1.75 mg·g−1 of reddish-purple biopigments. On the contrary, an absence of pigment production was observed during the fermentation of the commercial medium used as reference. According to our results, replacement of commercial culture media with available low-cost agroindustrial wastes for producing bioactive chemicals is a real opportunity to enhance the Streptomyces pigment production and antibiotic sustainability with cost-competitiveness. To our knowledge, this is the first report on the simultaneous production of biopigments and diffusible antifungal antibiotics produced by Streptomyces spp. using potato solid waste as the sole nutrient source.

Author(s):  
I. G. Nwosu ◽  
G. O. Abu ◽  
K. O. Agwa

Exopolysaccharides(EPSs) are essential metabolites synthesized and excreted by certain microorganisms in response to extreme condition of pH, temperature, salinity, osmotic stress and other contaminants for survival in such adverse environment. The present study focuses on isolation of exopolysaccharide producing bacteria from extreme environment of oil polluted soil of Ogoni land and marine water of Bonny Island. Screening of EPS producing abilities of the selected isolates were estimated using two approaches viz gravimetric analysis of EPS dry weight and quantification assay for total carbohydrate content by phenol sulphuric acid method. Result revealed that a total of forty (40) different colonies were suspected to produce exopolysaccharide after preliminary screening by selecting thick ropy-like colony formers on agar medium. Secondary screening indicated that twelve (12) isolates produced precipitates above 1000mg/l of total dry weight and eight (8) isolates produced highest EPS yield above 1000mg/l of culture media with carbohydrate content determination. Five isolates with the code WAS1, WAS11, SC6, SOS7 and SOS10 produced significantly higher EPS compared to other bacterial colonies isolated and were termed as most potent EPS producers. These isolates were identified based on 16S rDNA sequence as Providencia stuarti, Escherichia coli, Shewanella chilikensis and Bacillus nealsonii. The result of the present study indicated that these strains have the potentials of producing high exopolysaccharides and can be explored in biotechnological industries.


1969 ◽  
Vol 60 (1) ◽  
pp. 91-100 ◽  
Author(s):  
Charles S. Nicoll

ABSTRACT The response of the pigeon crop-sac to systemically acting prolactin (injected subcutaneously) was evaluated by measuring the wet weight of the responsive lateral lobes of the organ and by determining the dry weight of a 4 cm diameter disc of mucosal epithelium taken from one hemicrop. Of several different injection schedules tested, administration of prolactin in four daily injections was found to yield optimal responses. When compared with a graded series of prolactin doses, measurement of the mucosal dry weight proved to be a better method of response quantification than determination of the crop-sac wet weight with respect to both assay sensitivity and precision. The submucosal tissue of the crop-sac was estimated to constitute about 64 % of the total dry weight of the unstimulated organ and it was found to be relatively unresponsive to prolactin stimulation in comparison with the mucosa. The lipid content of the mucosal epithelium was determined using unstimulated crop-sacs or tissues which showed varying degrees of prolactin-induced proliferation. The fat content of the mucosal epithelial cells increased only slightly more rapidly than the dry weight or the defatted dry weight of the mucosa. Suggestions are made for the further improvement of the systemic crop-sac assay for prolactin.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 506d-506
Author(s):  
Robert R. Tripepi ◽  
Holly J. Schwager ◽  
Mary W. George ◽  
Joseph P. McCaffrey

Two insecticides, acephate or azadirachtin, were added to tissue culture media to determine their effectiveness in controlling onion thrips (Thrips tabaci Lindeman.) and to determine if these insecticides could damage the plant shoot cultures. To test for insecticide phytotoxicity, microshoots from European birch (Betula pendula), American elm (Ulmus americana), `Pink Arola' chrysanthemum (Dendranthema grandiflora), `America' rhododendron (Rhododendron catawbiense), `Golden Emblem' rose (Rosa hybrida), and `Gala' apple (Malus domestica) were placed in 130-ml baby food jars containing 25 ml of medium supplemented with 6.5, 13, or 26 mg/l Orthene® (contained acephate) or 0.55, 1.1, or 2.2 ml/l Azatin® (contained azadirachtin). Control jars lacked insecticide. To test for thrips control, 13 mg/l Orthene® or 0.55 ml/l Azatin® was added to Murashige and Skoog medium, and 10 thrips were placed on `Gala' apple microshoots in each jar. Jars were sealed with plastic wrap. In both studies, microshoot dry weight and heights were determined. In the second study, the total number of thrips per jar was also determined 3 weeks after inoculation. Microshoots on Orthene®-treated media lacked phytotoxicity symptoms, regardless of the concentration used. In contrast, Azatin® hindered plant growth, decreasing shoot height or dry weight by up to 85% depending on the species. Both insecticides prevented thrips populations from increasing, since less than 10 thrips were found in jars with insecticide-treated medium. Control jars, however, contained an average of almost 70 thrips per jar. This study demonstrated that both Orthene® and Azatin® were effective for eradicating thrips from plant tissue cultures, but Orthene® should probably be used because Azatin® was phytotoxic to all species tested.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 468b-468
Author(s):  
Stephen F. Klauer ◽  
J. Scott Cameron ◽  
Chuhe Chen

After promising results were obtained with an open-style split trellis (two top wires) in its initial year, two new trials were established in 1997 in northwest (Lynden) and southwest (Woodland) Washington. For the split trellis, actual yields were 33% (machine-picked 1/2 season) and 17% (hand-picked) greater, respectively, for the two locations compared to the conventional trellis (one top wire). In Woodland, canes from the split trellis had 33% more berries, 55% more laterals, 69% more leaves, and 25% greater leaf area compared with the conventional trellis. Greatest enhancement of these components was in the upper third of the canopy. Laterals were also shorter in this area of the split canopy, but there was no difference in average total length of lateral/cane between trellis types. Total dry weight/cane was 22% greater in the split trellis, but component partitioning/cane was consistent between the two systems with fruit + laterals (43%) having the greatest above-ground biomass, followed by the stem (30% to 33%) and the leaves (21% to 22%). Measurement of canopy width, circumference, and light interception showed that the split-trellis canopy filled in more quickly, and was larger from preanthesis through postharvest. Light interception near the top of the split canopy was 30% greater 1 month before harvest with 98% interception near the top and middle of that canopy. There was no difference between the trellis types in leaf CO2 assimilation, spectra, or fluorescence through the fruiting season, or in total nitrogen of postharvest primocane leaves.


Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1151
Author(s):  
Sadam Hussain ◽  
Saddam Hussain ◽  
Zubair Aslam ◽  
Muhammad Rafiq ◽  
Adeel Abbas ◽  
...  

Dry direct-seeded rice has been shown to save irrigation water and labor. Nonetheless, irrigation management in dry direct-seeded rice has received very little attention. Here, we examined the potential of different irrigation regimes: aerobic rice (AR), alternate wetting and drying (AWD) and continuous flooding (CF) in dry direct-seeded rice cultivation on two rice cultivars (Pride-1 (hybrid indica) and NB-1 (inbred indica)). Growth, yield attributes, grain yield, total water input, water productivity and benefit cost ratio were measured. Our results showed that AR saved 11.22 and 28.40%, and 5.72 and 32.98% water compared with AWD and CF during 2018 and 2020, respectively. There was a significant difference in grain yield among treatments and cultivars. AWD and CF produced statistically same total dry weight and grain yield, while AR reduced the total dry weight by 31.34% and 38.04% and grain yield by 34.82% and 38.16% in comparison to AWD and CF, respectively, across the years. Except for 1000-grain weight and harvest index in AWD and CF, further differences in total dry weight and grain yield among irrigation treatments were primarily correlated with variations in yield attributes. Among the cultivars, hybrid rice performed better than inbred rice. Over the two-year period, hybrid rice increased total dry weight, grain yield, and water productivity by 9.28%, 13.05%, and 14.28%, respectively, as compared to inbred rice. Regarding water productivity (WP), the maximum percentage (40.90 and 26.53%) was recorded for AWD compared to AR and CF. Among cultivars, more water productivity (14.28%) was calculated for hybrid rice than inbred one. Chlorophyll and carotenoid contents, leaf area index and crop growth rate contributed to higher grain yield of hybrid rice under AWD and CF. In contrast to WP, the maximum benefit cost ratio was estimated to be higher for CF than that of AR and AWD. For the cultivars, the maximum value (2.26 in 2018 and 2.32 in 2020) was calculated for hybrid rice compared with the inbred one. In conclusion, these results suggests that AWD with maximum WP and CF with maximum BCR could be more efficient approaches than AR. Under CF, hybrid rice cultivars with higher yield and yield-related attributes, WP and BCR performed better.


2020 ◽  
Vol 11 (1) ◽  
pp. 174
Author(s):  
Konstantinos P. Papadopoulos ◽  
Christina N. Economou ◽  
Athanasia G. Tekerlekopoulou ◽  
Dimitris V. Vayenas

Algal/cyanobacterial biofilm photobioreactors provide an alternative technology to conventional photosynthetic systems for wastewater treatment based on high biomass production and easy biomass harvesting at low cost. This study introduces a novel cyanobacteria-based biofilm photobioreactor and assesses its performance in post-treatment of brewery wastewater and biomass production. Two different supporting materials (glass/polyurethane) were tested to investigate the effect of surface hydrophobicity on biomass attachment and overall reactor performance. The reactor exhibited high removal efficiency (over 65%) of the wastewater’s pollutants (chemical oxygen demand, nitrate, nitrite, ammonium, orthophosphate, and total Kjeldahl nitrogen), while biomass per reactor surface reached 13.1 and 12.8 g·m−2 corresponding to 406 and 392 mg·L−1 for glass and polyurethane, respectively, after 15 days of cultivation. The hydrophilic glass surface favored initial biomass adhesion, although eventually both materials yielded complete biomass attachment, highlighting that cell-to-cell interactions are the dominant adhesion mechanism in mature biofilms. It was also found that the biofilm accumulated up to 61% of its dry weight in carbohydrates at the end of cultivation, thus making the produced biomass a suitable feedstock for bioethanol production.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Han Wang ◽  
Gloria M. Conover ◽  
Song-I Han ◽  
James C. Sacchettini ◽  
Arum Han

AbstractAnalysis of growth and death kinetics at single-cell resolution is a key step in understanding the complexity of the nonreplicating growth phenotype of the bacterial pathogen Mycobacterium tuberculosis. Here, we developed a single-cell-resolution microfluidic mycobacterial culture device that allows time-lapse microscopy-based long-term phenotypic visualization of the live replication dynamics of mycobacteria. This technology was successfully applied to monitor the real-time growth dynamics of the fast-growing model strain Mycobacterium smegmatis (M. smegmatis) while subjected to drug treatment regimens during continuous culture for 48 h inside the microfluidic device. A clear morphological change leading to significant swelling at the poles of the bacterial membrane was observed during drug treatment. In addition, a small subpopulation of cells surviving treatment by frontline antibiotics was observed to recover and achieve robust replicative growth once regular culture media was provided, suggesting the possibility of identifying and isolating nonreplicative mycobacteria. This device is a simple, easy-to-use, and low-cost solution for studying the single-cell phenotype and growth dynamics of mycobacteria, especially during drug treatment.


Weed Science ◽  
1988 ◽  
Vol 36 (6) ◽  
pp. 751-757 ◽  
Author(s):  
David T. Patterson ◽  
Maxine T. Highsmith ◽  
Elizabeth P. Flint

Cotton, spurred anoda, and velvetleaf were grown in controlled-environment chambers at day/night temperatures of 32/23 or 26/17 C and CO2concentrations of 350 or 700 ppm. After 5 weeks, CO2enrichment to 700 ppm increased dry matter accumulation by 38, 26, and 29% in cotton, spurred anoda, and velvetleaf, respectively, at 26/17 C and by 61, 41, and 29% at 32/23 C. Increases in leaf weight accounted for over 80% of the increase in total plant weight in cotton and spurred anoda in both temperature regimes. Leaf area was not increased by CO2enrichment. The observed increases in dry matter production with CO2enrichment were caused by increased net assimilation rate. In a second experiment, plants were grown at 350 ppm CO2and 29/23 C day/night for 17 days before exposure to 700 ppm CO2at 26/17 C for 1 week. Short-term exposure to high CO2significantly increased net assimilation rate, dry matter production, total dry weight, leaf dry weight, and specific leaf weight in comparison with plants maintained at 350 ppm CO2at 26/17 C. Increases in leaf weight in response to short-term CO2enrichment accounted for 100, 87, and 68% of the observed increase in total plant dry weight of cotton, spurred anoda, and velvetleaf, respectively. Comparisons among the species showed that CO2enrichment decreased the weed/crop ratio for total dry weight, possibly indicating a potential competitive advantage for cotton under elevated CO2, even at suboptimum temperatures.


1972 ◽  
Vol 50 (11) ◽  
pp. 2097-2102 ◽  
Author(s):  
R. Hall ◽  
H. Ly

The development of microsclerotia of Verticillium dahliae from a few swollen hyaline cells on a hypha to a multicellular, pigmented "mature" structure is described and illustrated. A method for quantitatively estimating the amount of pigmented microsclerotial material in pure cultures was developed to study quantitative relations between mycelial growth and production of microsclerotial material in media containing different concentrations of glucose. At low glucose concentrations (0.6 to 10 mg/ml) microsclerotial material continued to increase after total dry weight of the cultures had reached a maximum, suggesting conversion of hyaline to pigmented material. At high glucose concentrations (20 to 60 mg/ml) the patterns of increase in total dry weight, microsclerotial material, and hyaline material were similar over a 4-week incubation period. Maximum production of both pigmented and hyaline materials occurred at a glucose concentration of 30 mg/ml (carbon/nitrogen ratio of 50/1).


1982 ◽  
Vol 12 (4) ◽  
pp. 936-946 ◽  
Author(s):  
J. P. Guyon ◽  
A. Kremer

A study of geographic variation of maritime pine (Pinuspinaster Ait.) 9 years old, regarding height growth, transpiration and sap pressure daily kinetics has been performed in two sites, one in coastal sand dune and the other one in a more interior well-drained sandy moor. Successive height increments were measured from the 4th to the 9th year of growth and the year × provenance interaction was investigated. Transpiration and sap pressure were measured on 2-year-old needle fascicles. Results show discriminant variations between provenances and suggest some hypotheses about the possible ways of natural selection concerning drought resistance. The provenances North Landes (France) and Leiria (Portugal) grow best and strongly react to any variation of environmental factors as reflected by the high value of the slope of their regression lines (regression of their annual mean on the overall annual mean). Such a genotypie instability coincides with an intense physiologic activity (large flux of water correlated with a strong loss of weight by transpiration, reaching after 3 min 2% of the total dry weight of the separated needles and associated with the lowest sap pressure when the sun is around zenith). On the contrary, the Morocan provenance Tamjoute shows a large stability; its daily curves of transpiration and sap pressure reach early their maximum and minimum and therefore express a stress avoidance. Between these two extreme behaviours, the provenances Cazorla (south Spain) and Porto-Vecchio (Corsica) have intermediate values of transpiration and sap pressure, and their height growth shows a relative stability of response to environmental change.


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