Draft Genome Sequence of Scheffersomyces spartinae ARV011, a Marine Yeast Isolate

We report the draft genome sequence of Scheffersomyces spartinae ARV011, which was isolated from the Great Sippewissett Marsh in Falmouth, Massachusetts. Sequencing was performed using the Illumina NovaSeq 6000 platform, yielding 7,598,030 read pairs 250 bp in length. This resulted in a total draft genome size of 12,132,557 bp.

Short Communication: Isolation and screening of polyhydroxylalkanoates producing microorganisms from Thailand

Pungsungvorn N, Wisetsing A. 2021. Short Communication: Isolation and screening of polyhydroxylalkanoates producing microorganisms from Thailand. Biodiversitas 22: 4963-4967. Polyhydroxylalkanotes (PHAs) are polyesters produced in nature by numerous microorganisms. They are biodegradable and are used in the production of bioplastics. In this study, one hundred twenty samples from different regions of Thailand were collected and screened for polyhydroxylalkanoates (PHAs) producing microorganisms. The samples were screened on YM agar containing 0.5 µg Nile-red/mL (YM-NR). Only one isolate of yeast (Y1) gave a positive result on PHA accumulation. The yeast isolate (Y1) was identified as Candida tropicalis by API 20C AUX kit and 18S rRNA nucleotide comparison. The yeast isolate Y1 produced 2.62% PHA when grown in synthetic N-limiting medium using rice straw hydrolysate as carbon source. The selected four bacteria (B1, B2, B3 and B4) were identified by BlastN of 16S rRNA as Enterobacter cloacae, Enterobacter carcerogenus, Escherichia coli and Klebsiella pneumonia, respectively. The selected yeast and bacterial strains gave PHA content of 2.62, 2.76, 5.38, 3.66 and 0.44%, respectively, in synthetic N-limiting medium using rice straw hydrolysate. Hence, these microorganisms could be used in PHA production from biomass in the future.

Probing cellulolytic yeast from forest ecosystem for the saccharification of Napier fodder biomass

Aim: This study aimed to search for novel cellulolytic isolates with high cellulase titre for the production of fuels and chemicals. Methodology: The yeast isolate YES5 isolated from the forest soil was screened for cellulase production. The cellulase activity of YES5 was optimized via RSM. The saccharification potential of YES5 using Napier biomass as substrate was evalauted. Results: The maximum cellulase activity obtained after optimizing pH, temperature, and incubation period was 35.70 U. A reliable statistical model was developed for maximizing the cellulase activity in YES5 Trichosporon asahii. The cellulase activity was 23.87U, when carbon source in CMC medium was replaced by Napier biomass. The maximum saccharification potential of 33.15% was observed on 3rd day. Interpretation: The study of optimizing the media composition of Trichosporon asahii cellulase using Napier biomass, a natural source of carbon for maximizing the cellulase production via RSM, is first of its kind.

Screening of Fungal Endophytes for their Biocontrol Potential against Rhizopus sp. Isolated from Diseased Cassava (Manihot esculenta Crantz)

The aim of this study was to screen for the bio-control potential of fungal endophytes isolated from cassava against a test pathogen of cassava. Fungal endophytes and pathogen were isolated and identified from healthy and diseased cassava respectively. The isolated fungal endophytes were screened for their biocontrol potential against a test pathogen using the dual culture and culture filtrate assay. Fusarium sp., Botryosphaeria sp., Colletotrichum sp., yeast isolate 1 and 2 were the isolated fungal endophytes while the pathogen was Rhizopus sp. The effect of endophytes on the mycelia growth of Rhizopus sp. using the dual culture assay indicated that yeast isolate 1 & 2 and Colletotrichum sp. were effective in inhibiting the mycelia growth of the test pathogen while Fusarium sp. and Botryosphaeria sp. were not effective. The co-culture of yeast isolate 2 with the test pathogen gave the lowest mycelia growth (1.66a±0.09) at day 2. The effect of endophytic culture filtrate on the mycelia growth of Rhizopus sp. showed that Fusarium sp. gave the lowest mycelia growth in the three days observed. The findings from this study suggested that the test endophytes have biocontrol potential against Rhizopus sp. The biocontrol abilities of the test endophytes vary using the dual culture and culture filtrate assay.

Estimation of Indole Acetic Acid and Phosphate Solubilisation by the Yeasts Isolated from the Leguminous Crops

Aim: The present study was aimed to estimate the quantity of IAA production and Phosphate solubilisation by the isolated yeasts from the leguminous crops. Place and Duration of Work: The experiments were carried out in the Department of Agricultural Microbiology, University of Agricultural Sciences, GKVK, Bengaluru during 2019-2020. Methodology: Yeasts were isolated from the leguminous crops such as Red gram, Cowpea, Green gram, Black gram and Bengal gram. Thirty-five yeast isolates were obtained using four media and were subjected to IAA production test and Phosphorus solubilisation by Spectrophotometry method. All the yeast isolates were subjected to the temperature tolerance test at 25, 30, 35 and 40°C. Results: Yeast isolate, CP15SI21 has found to produce the highest IAA under in vitro conditions 30.50 μg/ml and the lowest was found to be 17.16μg/ml by yeast isolate BG20SI29. 24 yeast isolates were found to produce above 20 μg/ml. In the case of Phosphate solubilisation highest was observed in GG7SI9 (25.70 mg/l) and lowest in BG6SI8 (1.20 mg/l). Seven isolates showed Phosphate solubilisation above 10 mg/l. At 35°C all the yeast isolates have shown very good growth compared to other lower temperatures. All the yeast isolates were found to grow in the media supplemented with micronutrients such as zinc and potassium. Conclusion: Our study highlights the potential of yeasts isolated from the leguminous crops that can help in plant growth promotion as the yeast isolates are capable of producing higher amounts of IAA. Some of the yeast isolates can solubilise phosphate under in vitro conditions which in turn helps in the utilization of unavailable P from soils thereby improves plant growth and tolerance to a higher temperature can alleviate abiotic stress.

Sensorial and Volatile Analysis of Wines Made from Partially Dehydrated Grapes: An Ontario Case Study

Winemaking in cool climate viticultural areas can pose challenges due to difficulties in achieving optimal ripeness from climatic conditions that tend to vary vintage-to-vintage. To stabilize quality, the use of partially dehydrated grapes has been indicated as beneficial to the production of high-quality wine (“appassimento” style) despite climatic variation. Postharvest wine grape dehydration is a complex process that involves the concentration or formation of sugars, aromas, and flavours. One of the quality challenges facing appassimento style winemaking is elevated levels of undesirable oxidation compounds. The aim of this study was to characterize wines made from a local yeast isolate, Saccharomyces uvarum CN1, which demonstrates limited osmotolerance and may have application to this wine style, as it is a known lower producer of such compounds. Wines made with CN1 were compared to wines made with the accepted commercial standard, S. cerevisiae, EC1118. Fermentations (n = 24) were established at three target starting sugar concentrations from dehydrated Cabernet franc grapes (24.5, 26.0, and 27.5°Brix) and a control (21.5°Brix) and were assessed for volatile organic compound (VOC) composition via gas chromatography-mass spectrometry (GC-MS). Wines also underwent quantitative descriptive analysis to identify and quantify sensory attributes by a trained panel (n = 11). Results show that the wines fermented with the yeast isolate contain significant differences in the concentrations of VOCs in the wines. Sensorially, the wines differed in intensity for a number of attributes, including red fruit aroma, black fruit flavour, and length of finish both within Brix treatments and amongst yeast strains. The most important differentiating factor amongst these wines was the combination of yeast strain at the highest starting sugar concentration (27.5°Brix). These findings may assist winemakers by informing the yeast strain choice for optimizing appassimento style wine quality in cool climates.

Screening and characterisation of β-glucosidase production strains from Rosa roxburghii Tratt

The β-glucosidase properties from one yeast isolate identified as Wickerhamomyces anomalus C4 were characterised. The β-glucosidase activity of W. anomalus C4 was 41.83 ± 0.25 mU/mL, and the optimum temperature and pH were 40 °C and 5.0, respectively. The glucose, 10% v/v of ethanol and 10 mmol/L of Cu2+ inhibited the β-glycosidases activities. The isolate W. anomalus C4 had a stronger alcohol metabolism capacity than commercial Saccharomyces cerevisiae X16. Besides, fermentation with W. anomalus C4 alone and co-fermentations with S. cerevisiae X16 and W. anomalus C4 reduced the volatile acids content and the sourness value compared to S. cerevisiae X16 control. Moreover, inoculation with W. anomalus C4 could enhance volatile aroma richness and complexity of Rosa roxburghii wines, regardless of type or amount thereof. Therefore, the R. roxburghii native yeast isolate W. anomalus C4 may have some application potentials for R. roxburghii wine-making.

Optimization, purification and antitumor Activity of Kodamaeoh MRI ANOMY L-Asparaginase MN611146 Isolated from Banana Peel

: L-Asparaginase is an important enzyme which converts L-asparagine to L-aspartate and ammonia. Microbial Lasparaginase has important applications as anticancer and food processing agents. This study described the isolation, screening of a local yeast isolate from banana peel for L-asparaginase production using submerged fermentation, optimization of the production, purification, and anticancer assay of L-asparaginase. The yeast isolate was identified as Kodamae ohmri ANOMY based on the analysis of nuclear large subunit (26S) rDNA partial sequences. It was a promising L-asparaginase producer with a specific activity of 3059±193 U/mg in a non-optimized medium. The classical one-variable-at-a-time method was used to optimize the production medium components, and it was found that the elimination of K2HPO4 from the medium increased L-asparaginase specific activity (3100.90±180 U/mg). Statistical optimization of L-asparaginase production was done using Plackett-Burman and Box–Behnken designs. The production medium for the maximum L-asparaginase specific activity (8500±578U/mg) was as follows (g/L): L-asparagine (7.50), NaNO3 (0.50), MgSO4.7H2O (0.80), KCl (0.80) associated with an incubation period of 5 days, inoculum size of 5.60 %, and pH (7.0). The optimization process increased L-asparaginase production by 2.78-fold compared to the non-optimized medium. L-Asparaginase was purified using ammonium sulphate precipitation followed by gel filtration on a Sephadex G-100 column. Its molecular weight was 66 KDa by SDS-PAGE analysis. The cell morphology technique was used to evaluate the anticancer activity of L-asparaginase against three different cell lines. L-Asparaginase inhibited the growth of HepG-2, MCF-7, and HCT-116 cells at a concentration of 20, 50, and 60 µL, respectively.