The objectives of the present study were to evaluate the chlorophyll content of green leafy vegetables found commercially and carry out a comparative investigation between in vivo and in vitro data. The chlorophyll of green leafy vegetable can be used as visible parameters of the quality of vegetables during storage, since it will be degraded gradually along with post-harvest senescence. Therefore, the development of reliable in vivo chlorophyll measurement should be advantageous rather than visual observation for the purpose of quality control and product sortation. Here, the existence of chlorophylls in ten green leafy vegetables were reported as SPAD values of a handheld SPAD-502 chlorophyll meter and % N of an Agriexpert CCN-6000 nitrogen meter (in vivo data), as well as total peak area data of HPLC measurement for chlorophyll a and b after exhaustive extraction using methanol (in vitro data). Both in vivo and in vitro measurement gave comparable grouping of vegetables with high and low content of chlorophyll. Moreover, correlation plots between SPAD values and total peak area of HPLC showed adequate linear correlation (R 2 > 0.7), revealing the potency of in vivo observation for the prediction of actual chlorophyll content in commercial leafy vegetables. SPAD values and % N presented strong linear relationship (R 2 > 0.9), in which SPAD-meter performed better detection at very low values. The calibration curve for each species of vegetable should be substantial to overcome the limiting factors of in vivo observation, such as leaf size, tissue thickness, and variation of chloroplast distribution.

Red pigmented marine bacteria, Pseudoalteromonas rubra strains PS1 and SB14, were isolated from two sampling locations in different ecosystems on Alor Island, Indonesia, and cultured in the laboratory. We analyzed the 16S rRNA gene sequences and examined the pigment composition and found that both strains produced cycloprodigiosin (3), prodigiosin (4), and 2-methyl-3-hexyl-prodiginine (5) as major compounds. In addition, we detected three minor compounds: prodigiosin derivatives 2-methyl-3-propyl prodiginine (1), 2-methyl-3-butyl prodiginine (2), and 2-methyl-3-heptyl-prodiginine (6). To our knowledge, this is the first report that P. rubra synthesizes not only prodigiosin and cycloprodigiosin but also four prodigiosin derivatives that differ in the length of the alkyl chain. The antimicrobial activity of cycloprodigiosin, prodigiosin, and 2-methyl-3-hexyl-prodiginine was examined by a disk-diffusion test against Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Candida albicans. We found that, at a concentration of 20 μg/mL, cycloprodigiosin showed the greatest inhibition (25.1 ± 0.55 mm) against S. aureus.

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Karotenoid adalah pigmen yang memberikan warna kuning, jingga hingga merah. Karotenoid merupakan pigmen pendamping klorofil atau zat hijau daun yang menjalankan fungsi penyerapan energi cahaya untuk fotosintesis. Sumber karotenoid utama adalah tumbuhan, yang selanjutnya dikonsumsi dan dimetabolisme atau terakumulasi dalam tubuh hewan.  Terdapat lebih dari 3000 jenis karotenoid, dan beberapa jenis telah diketahui memiliki manfaat bagi kesehatan. Beberapa studi menyebutkan karotenoid berfungsi sebagai antioksidan, antikanker, dan membantu memelihara kesehatan mata. Ekstrak karotenoid telah diaplikasikan dalam berbagai produk pangan dan nutrasetikal. Dengan demikian, perkembangan teknologi metode ekstraksi karotenoid menjadi penting untuk diikuti. Ekstraksi karotenoid dilakukan dengan metode konvensional seperti maserasi ataupun modern seperti cairan superkritis, ultrasound asssisted extraction, enzimatik, pulsed electric field, dan pressurized liquid extraction. Sejumlah studi metode ekstraksi karotenoid dalam dekade terakhir disajikan dan dibahas dalam review berikut.

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