Use of Modified Lactobacillus Selective Medium and Bifidobacterium Iodoacetate Medium for Differential Enumeration of Lactobacillus acidophilus and Bifidobacterium spp. in Powdered Nutritional Products

1999 ◽  
Vol 62 (1) ◽  
pp. 77-80 ◽  
Author(s):  
STEVEN C. INGHAM

Modified Lactobacillus selective agar (APT agar + sodium acetate and glacial acetic acid; mLBS) was compared to selective modified Lactobacillus selective medium (LBS agar + tomato juice and acetic acid; mLSM) and nonselective de Man Rogosa Sharpe (MRS) agar for the enumeration of Lactobacillus acidophilus in probiotic-containing powdered nutritional products. The mLBS agar was equivalent to MRS agar and superior to the mLSM agar for enumerating L. acidophilus in products stored in sealed cans at 22°C. When samples were analyzed for L. acidophilus concentration after high temperature storage in sealed cans or storage in open cans at high relative humidity, the mLBS and MRS agars were highly correlated (r2 = 0.93). Modified Bifidobacterium iodoacetate medium (12.5 mg iodoacetic acid/liter; mBIM) was compared to MRS agar + bile, cysteine, and dicloxacillin (MRS + BCD) for enumerating Bifidobacterium infantis or Bifidobacterium lactis in the nutritional products. The two media were equivalent for enumerating B. infantis in product stored at 22°C in sealed cans. However, the two media were poorly correlated (r2 < 0.50) for enumeration of B. infantis and B. lactis in products stored in sealed cans at high temperature or in open cans at high relative humidity. The mLBS medium has potential industry application as a relatively inexpensive, convenient differential enumeration method for L. acidophilus. The mBIM medium cannot be recommended as a sole medium for enumeration of probiotic Bifidobacterium spp. in powdered nutritional products stored under high temperature and/or high relative humidity conditions.

2014 ◽  
Vol 104 (9) ◽  
pp. 091904 ◽  
Author(s):  
Bruno R. Matos ◽  
Cleverson A. Goulart ◽  
Elisabete I. Santiago ◽  
R. Muccillo ◽  
Fabio C. Fonseca

Wood Research ◽  
2021 ◽  
Vol 66 (3) ◽  
pp. 427-436
Author(s):  
Jiangyi Chu ◽  
Jinghui Jiang ◽  
Chusheng Qi ◽  
Yongdong Zhou

The purpose of this paper is to investigate the influence of kiln temperature, relative humidity and wood moisture content on the content of acid and alcohol released in the drying process of high temperature kiln by studying the radiated pine sawn timber of 40mm thickness. The drying temperature was between 101°C and 115°C, the relative humidity in the drying kiln was reduced from 86.1% to 39.6%, the moisture content of the lumber was reduced from 106.16% to 11.98%, and gas extraction was executed nine times with an extraction speed of 1.0 L•min-1 and a sampling time of 30 min. The concentrations of acids and alcohols were analyzed by HPLC. The results showed that the concentrations of formic acid, acetic acid, and methanol emitted in the kiln during drying were 215.6-748.2, 4148.8-16803.2, and 6381.9-15648.9 mg•m-3, respectively, and these concentrations were significantly higher than the relevant standards. The concentrations of the emitted formic acid and acetic acid were proportional to the drying temperature, the concentrations of the emitted formic acid and acetic acid were inversely proportional to the relative humidity in the kiln and the moisture content of the lumber. The concentration of the emitted methanol was independent of the drying temperature, relative humidity in the kiln, and moisture content of the lumber. It is therefore suggested that formic acid, acetic acid, and methanol be separately recovered during the high-temperature drying of Pinus radiata lumber.


1960 ◽  
Vol 38 (6) ◽  
pp. 1057-1061 ◽  
Author(s):  
J. A. Juillet

Analysis of the average captures of diurnal parasitic Hymenoptera in a pine plantation in relation to some weather elements showed that ichneumonids were most active at average temperatures (70–75° F), high relative humidity, and low wind velocity; braconids at high, temperature, low relative humidity, and low wind velocity; and chalcids at high temperature and low relative humidity, hut were unaffected by wind.


Weed Science ◽  
1969 ◽  
Vol 17 (4) ◽  
pp. 401-404 ◽  
Author(s):  
Earl R. Burns ◽  
Gale A. Buchanan ◽  
A. E. Hiltbold

Absorption and translocation of the sodium salt of radioactive (2,4-dichlorophenoxy)acetic acid (2,4-D-2-14C) by wolftail (Carex cherokeensis Schwein) plants grown from rhizomes were enhanced by high relative humidity but were not affected by dimethyl sulfoxide (hereinafter referred to as DMSO). Greatest accumulation of 2,4-D-2-14C translocated from the treated leaf occurred, in the meristematic tissue. DMSO increased the herbicidal activity of the triethanolamine salt of 2,4-D alone, but 2,4-D plus DMSO was no more effective than 2,4-D plus X-77. When both DMSO and X-77 were added to the 2,4-D solution, the treatments were no more effective than when either additive alone was included.


1977 ◽  
Vol 17 (85) ◽  
pp. 308 ◽  
Author(s):  
H Philpotts

In a series of experiments, different inoculation methods applied to seeds of Glycine wightii were compared for their effect on survival of rhizobia (Rhizobium sp.) under various conditions: high temperature with and without high relative humidity, exposure to sunlight, and contact with superphosphate. Seeds were inoculated with peat inoculum in gum arabic (gum treatment), in gum arabic plus a coating of lime or rock phosphate, or with peat inoculum in water (slurry). When subjected to 50�C for eight hours a day, survival of the cowpea-type Rhizobium strain CB756 was poorer at 75 per cent relative humidity than at 40 per cent. CB756 survived better than the clover strain TA1 under high temperature and high relative humidity, and neither lime nor phosphate pelleting increased survival of the two strains over the gum treatment. Poorest survival was with phosphate for TA1 and lime for CB756. When exposed to sunlight, numbers of CB756 fell most rapidly in the gum treatment but, after a longer period in a glasshouse at about 30�C, survival was poorest in the slurry treatment. When mixed with superphosphate, lime pelleting resulted in best survival of both strains. In pot experiments, lime pelleting resulted in a higher percentage of nodulated plants and higher plant weights of Trifolium subterraneum and Glycine wightii, the advantage being greatest when low numbers of rhizobia were on the seed at sowing.


2021 ◽  
Vol 1793 (1) ◽  
pp. 012077
Author(s):  
Ahmad Rasdan Ismail ◽  
Norfadzilah Jusoh ◽  
Nor Kamilah Makhtar ◽  
Raemy Md Zein ◽  
Ismail Abdul Rahman ◽  
...  

2014 ◽  
Vol 24 (4) ◽  
pp. 471-474 ◽  
Author(s):  
Yan-Ling Zheng ◽  
Huan-Cheng Ma

Mumian (Bombax ceiba) is a deciduous tree that can grow in the dry-hot valley of southwestern China. However, natural regeneration of mumian is significantly inhibited by some factors such as high temperature that can accelerate seed deterioration. The objective of this study was to identify the change of seedling growth component(s) in response to seed aging at 45 °C either at low relative humidity (15%) or at high relative humidity (100%) for 0, 1, 2, 3, and 4 days. Germination assay results at 30 °C in darkness showed an interaction between relative humidity and aging duration. At high temperature and low relative humidity seedling growth, weight of used seed reserve and fraction of seed reserve depletion significantly decreased with increasing of aging duration. But the conversion efficiency of mobilized reserve to seedling tissues did not change significantly. In contrast, at high temperature and high relative humidity, seedling growth and conversion efficiency of seed reserve utilization decreased significantly, but weight of used seed reserve and fraction of seed reserve depletion did not change significantly until seeds were dead. It was concluded that there existed a different pattern of seed reserve utilization for seeds aged at low and high relative humidity, and humidification of seeds at 45 °C for 1 day is a possible way to increase germination of mumian.


Weed Science ◽  
1976 ◽  
Vol 24 (6) ◽  
pp. 536-540 ◽  
Author(s):  
G. D. Wills

Translocation of14C-labeled and toxicity of nonradiolabeled bentazon [3-isopropyl-1H-2,1,3-benzothiadiazin-(4)3H-one 2,2-dioxide] was determined for common cocklebur (Xanthium pensylvanicumWallr.) and soybeans [Glycine max(L.) Merr.]. Significantly greater14C-movement and herbicide toxicity occurred in common cocklebur growing in wet soil at field capacity than in dry soil near the wilting point. In common cocklebur there was a trend toward greater bentazon toxicity and14C-translocation at high temperature (35 C) and high relative humidity (RH) (96%) than at low temperature (25 C) and low RH (35%). ‘Lee 68’ soybeans were injured less than 10% by bentazon under any environmental condition of this study. Translocation of14C was primarily acropetal in both common cocklebur and soybeans. Herbicide movement was affected by leaf maturity with the greatest movement of14C resulting from14C-bentazon applied to the most mature common cocklebur leaf near the base of the shoot and to soybeans at the youngest fully expanded leaf near the apex of the shoot. Bentazon was more toxic and14C translocation was greater in the soybean cultivar ‘Hurrelbrink’ than ‘Hill’ or Hill X Hurrelbrink cross.


2012 ◽  
Vol 102 (4) ◽  
pp. 421-428 ◽  
Author(s):  
N. Lalancette ◽  
K. A. McFarland ◽  
A. L. Burnett

The production of conidia by Fusicladium carpophilum on twig lesions was quantitatively modeled as a function of temperature and duration of high relative humidity. During peak sporulation periods in 2007, 2008, and 2009, 1-year-old twigs bearing abundant overwintering lesions were removed from a heavily infected ‘Redgold’ nectarine orchard, placed in trays at high relative humidity (>95%), and incubated at eight constant temperatures for seven durations, resulting in a factorial design of 56 treatment combinations. Conidia numbers were estimated with a hemacytometer. Results from a six-stage modeling process indicated that, at any given temperature, spore production during high relative humidity periods increased in a monomolecular- to Gompertz-like pattern. The Richards model, with shape parameters of 0.79 to 0.90, was found to provide the best overall fit. When the asymptote and rate parameters were derived as functions of temperature using Gaussian and quadratic models, respectively, the duration of high relative humidity and temperature described 90 to 94% of the variation in conidia production. Predictions of the final models were highly correlated with observed levels of sporulation (r > 0.94; P < 0.0001), indicating an excellent fit to the data. The optimum temperature for sporulation, based on fitting a Gaussian model to the maximum sporulation levels at each temperature, was 17.9 to 20.2°C, with an overall average of 18.8°C. The derived models give a quantitative description of sporulation by F. carpophilum and may have potential use in simulators and forecasting systems.


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