POs-Ca (Phosphoryl Oligosaccharides of Calcium) is a calcium salt of phosphoryl oligosaccharides made from potato starch. Recent studies have demonstrated that POs-Ca has various functions such as mineral supplementation and oral/skin care.

Structure and manufacturing process

Potato starch is a typical glucose polymer that contains ester-linked phosphate groups. Phosphoryl oligosaccharides (phosphoryl maltooligosaccharides) are produced through potato starch enzymatic hydrolysis. POs-Ca is produced as a calcium salt of phosphoryl oligosaccharides.
POs-Ca is composed of maltooligosaccharides in which at least one or two phosphate groups are bound with a calcium ion (maltotriose to maltooctaose).

                                         < Major components of POs-Ca >


High solubillty in water
POs-Ca, a food ingredient, is a highly water-soluble calcium substance. It dissolves easily even in water with high calcium concentration.
With its relatively high calcium level (5%) and extremely high water solubility, POs-Ca serves as an ingredient in food, beverages, supplements, and other oral products.


POs-Ca®(Phosphoryl Oligosaccharides of Calcium) containing 5% (w/w) calcium provides soluble calcium in saliva, and effectively enhances the remineralization and recrystallization of enamel lesions. Fluoride ions with POs-Ca are possibly effective against early caries lesion.

POs-Ca is applicable to caries prevention
POs-Ca has many merits in the application of caries prevention.

  1. Highly soluble calcium from POs-Ca in saliva
  2. Not be assimilated by mutans streptococci
  3. Avoiding the fall of plaque pH
  4. Promoting 3Rs for caries prevention
  5. 3Rs = Remineralization, Recrystallization, Rehardening

Clinical study
Each subject chewed 2 pieces of one of the following 3 types of chewing gum for 20 minutes at a time, 3 times daily for 14 consecutive days.
(1) : Sugarless chewing gum (2) : (1) + 2.5% POs-Ca (3) : (2) + fluoride (~1 ppm in saliva)

Remineralization (Ref.1,2)
POs-Ca-derived calcium in the saliva promoted the remineralization of early-stage caries lesion. Addition of fluoride promoted tooth remineralization even further. (See figure A)

Recrystallization (Ref.1,2)
The study was conducted at SPring-8, one of the world's biggest synchrotron radiation facilities. The results of the study demonstrated that the calcium deposited in the enamel of the tooth in the course of remineralization had the same ordered crystal structure as that of the healthy tooth. In other words, POs-Ca was restored the healthy tooth microstructure. Addition of fluoride promoted even further. (See figure B)

Rehardening (Ref.3)
Early-stage caries causes mineral loss and softening of the affected site of a tooth surface. The recovery of tooth hardness was shown to be enhanced by POs-Ca alone and even further by POs-Ca plus fluoride. (See figure C)

POs-Ca's calcium can be soluble with fluoride
POs-Ca can also be used with fluoride, which is beneficial in preventing caries. In the presence of fluoride ions, conventional calcium (e.g. calcium chloride) forms an insoluble salt. However, POs-Ca's calcium is kept soluble in saliva in the presence of fluoride (Left figure), and releases calcium in the enamel subsurface. In the presence of 0.5 to 1.0-ppm fluoride, which is comparable to fluoridated water, POs-Ca showed the best remineralization effect in an in vitro study (Right figure).

The product of chewing gum which containing POs-Ca is authorized as a Foods for Specified Health Uses (FOSHU) in Japan
FOSHU refers to foods that contain an ingredient with a beneficial health function and are officially approved to claim its physiological effects on the human body in Japan.


  1. Tanaka T et al. Archives of Oral Biology 58, 174-180 (2013)
  2. Kitasako Y et al. Journal of Dentistry 39, 771-779 (2011)
  3. Kitasako Y et al. Journal of Dental Research 91, 370-375 (2012)


POs-Ca®(Phosphoryl Oligosaccharides of Calcium) is a derivative of maltooligosaccharides characterized as a highly water-soluble calcium carrier. It is a novel active agent that is effective for improving skin barrier function and skin hydration and normalizing epidermal turnover.

In vitro study :

Effects of POs-Ca on cultured normal human epidermal keratinocyte (NHEK)
Several in vitro studies have shown that POs-Ca has a promoting effect on NHEK differentiation, induces the tight junction formation in NHEK and increases gene expression of stratum corneum reconstruction and hydration related molecules.

Cell differentiation
In NHEK cultured for 48 hours in the presence of POs-Ca, flattening and stratification of cells, a characteristic of differentiated NHEK, were observed (the left figure). Production of involucrin protein, a keratinocyte differentiation marker, was promoted in NHEK cultured for 144 hours in the presence of POs-Ca more than in NHEK cultured in the absence of POs-Ca (the right figure).

Tight-junction formation
Tight-junction formation in NHEK cultured for 48 hours in the presence of POs-Ca was evaluated by measuring transepithelial electrical resistance (TER). As a result, a marked increase in TER was observed in a POs-Ca concentration-dependent manner (the left figure). Immunostaining of tight-junction proteins (occludin, claudins) was performed using NHEK cultured for 144 hours in the presence of POs-Ca. Continuous honeycomb localization of the tight-junction proteins at cell borders were observed in POs-Ca treated cells (the right figure).

Gene expression for stratum corneum condition and skin hydration
Using NHEK cultured for 24 hours with the presence of 0.1% POs-Ca, expression of various genes was analyzed. It was confirmed that POs-Ca contributed to an increase in the expression of genes involved in stratum corneum condition, barrier function and skin hydration.
The results suggested that POs-Ca not only enhances barrier function by promoting tight-junction formation but also is involved in improving the condition of the stratum corneum and skin hydration function.

Intercellular lipids production
Production of intercellular lipids in NHEK cultured 144 hours in the presence of POs-Ca was evaluated by TLC. As a result, cholesterol and ceramides were significantly increased by the treatment of POs-Ca.

Clinical study :
Effects of POs-Ca on improvement in skin barrier function and stratum corneum (SC)

In a study in 21 female subjects (22 to 52 years old) who suffered from rough skin, aqueous solution of POs-Ca (2%) was applied to the face twice daily for 2 months. As a result, transepidermal water loss (TEWL) significantly decreased and stratum corneum hydration significantly increased.
In an analysis of the stratum corneum condition by tape stripping, a significant decrease in the level of multilayered desquamation of stratum corneum was observed. In addition, the surface area of the stratum corneum increased in subjects in their 20s and significantly decreased in subjects in their 40s to 50s.
Cutaneous administration of POs-Ca is expected to be effective for skin hydration, barrier function improvement, normalization of epidermal turnover, and other skin benefits.


( * by dry weight)

Appearance White powder
Solution Clear
pH ( 1% aq ) 5.5~7.0
Heavy metal(as Pb) ≦ 20 ppm
Arsenic(as As2O3) ≦ 2 ppm
Loss of drying ≦ 6.5 %
Residue on ignition ≦ 19 % *
Calcium 4.5~5.5 % *
Total aerobic microbial count ≦ 100 CFU/g
Total yeasts and moulds count ≦ 20 CFU/g
Escherichia coil Negative


Trade name POs-Ca
INCI name Calcium Phosphoryl Oligosaccharides

Other Information

Cas No. 1124316-47-7
for enquiries, contact Glico Nutrition Co., Ltd., Fine Chemicals Sales Department
4-6-5, Utajima, Nishiyodogawa-ku, Osaka 555-8502 Japan
FAX: +81 6-6477-8267
E-MAIL: g-material@glico.co.jp