A Simple Method for Measuring the Starch and Lipid Contents in the Cell of Microalgae

Abstract

SummaryWe used a microplate-based method to quantify microalgal lipids with Nile Red staining and a fluorescence microplate reader. However, a method to quantify starch that combines microplates with staining has not been reported. Therefore, we examined microplate-based quantification of lipids using Nile Red staining and of starch using Lugol staining. Neither starch nor lipids accumulated during the zero phase of cultured Parachlorella kessleri, only starch accumulated during the starch phase, and starch was subsequently lost and lipids accumulated during the oil phase. The quantities of starch and lipids were measured using a microplate-based method, which indicated linear production of starch and lipids within limited ranges (lipids, 0.071-0.380 g mL 1 ; starch, 155-404 mg mL 1 ) when standard curves were prepared for lipids extracted with methyl tertiary-butyl ether and for starch extracted with anthrone. The concentration of starch produced during the starch phase was 0.59 mg mL 1 and that of lipids during the oil phase was 2.49 mg mL 1. The concentration of starch produced was 0.05-0.13 mg mL 1 during phases other than the starch phase, and lipids were not detected other than during the oil phase because lipid contents were approximated based on the quantity of triacylglycerol, which stains with Nile Red.

Highly efficient lipid production in the green alga Parachlorella kessleri: draft genome and transcriptome endorsed by whole-cell 3D ultrastructure

“…Briefly, total lipids were extracted using methyl- tert -butyl ether (MTBE) [ 47 ], and the weight of total lipids was measured gravimetrically using a precision analytical balance. Starch content was quantified using the Lugol staining method as described [ 48 ]. Growth curves were estimated using a general linear model ( glm function), and other curves (except for starch assay) were fitted using the ksmooth function in R statistical software v. 3.1.0.…”

SUPER STARCHY1/ONAC025 participates in rice grain filling

“…After removing the paraplast in the ribbon by two rounds of xylene treatment, the slides were then stained separately with Coomassie brilliant blue/CBB [0.25% CBB in 50% methanol and 10% acetic acid] or 0.25% Toluidine blue‐O/TBO to observe shoot apical meristem (SAM) structure. Slides were stained with 2% KI/I 2 (Lugol’s solution; Takeshita et al, 2015) to observe starch. Excessive staining was removed by dipping the slides in 50% ethanol.…”

Worldwide Research Trends on Microalgae and Recent Work in Cytologia

“…Basic research on the breeding of microalgae strains and the value of biomass will contribute to these advances. More reports on microalgae biotechnologies in Cytologia are indispensable, such as those of Ota et al (2014) and Takeshita et al (2015).…”