현재 식품공전 및 식품첨가물 공전에서 포도씨유 및 추출물의 catechin 함량 측정방법으로 널리 사용되고 있는 바닐린비색법을 polyamide cartridge를 사용함으로써 개선하였고 보다 정확하며 재현성 있게 catechin 함량을 측정할 수 있는 HPLC 방법을 개발하였다. 포도씨유 및 용매(열수, 에탄올, 메탄올 및 아세톤)추출물의 catechin 함량을 바닐린비색법으로 측정한 결과 각각 $30{sim}40;mg%$ (g/포도씨유 100g) 및 $17{sim}43%$(g/추출물 100g) 범위를 차지하였다. 반면, polyamide cartridge를 사용한 개량 바닐린비색법으로 위의 포도씨유 및 추출물의 catechin 함량을 측정한 결과 각각 미량($1{sim}5ppm$) 및 $4.0{sim}7.5%$ 차지하였다. 한편, HPLC 방법으로 포도씨유의 catechin 함량을 측정한 결과 포도씨의 주된 4가지 catechin 성분[(+)-catechin, procyanidin $B_2$, (-)-epicatechin 및 (-)-epicatechin gallate]은 거의 확인할 수 없었다. 그러나 포도씨 용매추출물의 catechin 함량을 측정한 결과 4가지 주된 catechin 성분을 확인할 수 있었으며, 그 중 (+)-catechin 및 (-)-epicatechin 함량이 각각 $1.35{sim}2.60%$ 및 $2.35{sim}4.59%$ 범위로서 상당히 높은 반면, procyanidin $B_2$ 및 (-)-epicatechin gallate 함량은 각각 $0.77{sim}1.36%$ 및 0.06${sim}0.30%$ 범위로서 상대적으로 낮았다 또한, HPLC에 의해 국내의 포도 품종별 및 산지별 포도씨의 catechin 조성 함량을 측정하였다. 이와같이 위에서 정립된 HPLC 방법에 의한 포도씨의 4가지 주된 catechin 성분의 회수율은 95% 이상으로 높았으며, 재현율은 모두 5% 미만의 편차를 나타내어 분리효율이 우수하였다. 그리고 4가지 catechin 성분의 검출한계는 $1{sim}5;ppm$ 범위를 나타내었다.
An improved method in place of a conventional vanillin spectroscopic method (CVSM) was developed for determination of catechin and its derivatives in extract and oil of grape seeds. For the CVSM, grape seed extracts had relatively high catechin content in the range of $17{sim}43%$ (g/100g of extract), while grape seed oils had relatively smaller catechin content in the range of $30{sim}40mg%$ (mg/100g of oil). For the improved vanillin spectroscopic method (IVSM) using a polyamide cartridge, catechin content of grape seed extracts was in the range of $4.0{sim}7.5%$, while that of grape seed oils was below 5 ppm. Meanwhile, the quantities of catechin and its derivatives were determined by HPLC in the grape seed extracts and oils. Four major catechins [(+)-catechin, procyanidin B2, (-)-epicatechin, and epicatechin gallate] were detected from grape seed extracts, and the ranges of concentrations were as follows: (+)-catechin, $1.35{sim}2.60%$; procyanidin $B_2$, $0.77{sim}1.36%$; (-)-epicatechin, $2.35{sim}4.59%$; (-)-epicatechin gallate, $0.06{sim}0.30%$. In contrast, four catechins were barely detectable in the grape seed oils. The reproducibility of four major catechins in grape seed extracts, given as coefficient of variation, was below 5%, and the recovery close to above 95%. The achieved detection level of four catechins was $1{sim}5;ppm$. Additionally, the contents of catechin compositions in grape seed extract were also determined by HPLC in relation to different cultivars and producing areas. Thus, HPLC method and IVSM using polyamide cartridge can be used as alternative to CVSM for determination of catechin and its derivatives in extract and oil of grape seeds.
