مقایسه خواص آنتی اکسیدانی بین عصاره‌ سه گونه جلبک بومی سبز و قهوه‌ای در سواحل شمالی دریای عمان

نوع مقاله : مقاله پژوهشی

نویسندگان

گروه شیلات، واحد چابهار، دانشگاه آزاد اسلامی، چابهار، ایران

10.22034/aej.2022.333075.2772

چکیده

حضور ماکروجلبک ‌ها در زیستگاه‌ های آبی بسیار حائز اهمیت می‌باشد. این گیاهان امروزه به عنوان منابع غنی از آنتی‌ اکسیدان ‌های طبیعی مورد توجه بسیاری از محققین قرار گرفته ‌اند. آنها اثرات سودمند متعددی روی فعالیتهای بیولوژیکی مانند آنتی اکسیدان ها و سمیت سلولی از خود نشان داده اند. در همین ارتباط در پژوهش حاضر خواص آنتی اکسیدانی سه گونه از ماکرو جلبک‌ های بومی در سواحل شمالی دریای عمان (استان سیستان و بلوچستان) بررسی و مقایسه شد. نمونه برداری در فصول پاییز و زمستان 1397 از سواحل شمالی دریای عمان (خلیج چابهار) انجام شد. نمونه‌ های مورد مطالعه شامل یک گونه جلبک سبز (Ulva lactuca) و دو گونه جلبک قهوه‌ای (Sargassum illicifolium و Nizamuddinia zanardinii) بود. این گونه‌ها به شکل غالب در سواحل شمالی دریای عمان حضور دارند. بعد از نمونه برداری جلبک ها توسط آب دریا و سپس آب شیرین شستشو شدند.سپس نمونه های تهیه شده خشک و سپس آسیاب گردیدند. تهیه عصاره در سه مرحله انجام شد. مراحل اول و دوم توسط آب مقطر و مرحله سوم توسط حلال متانول بود. سنجش میزان آنتوسیانین و محتوای فلاونوئیدی به روش اسپکتوفتومتری انجام شد. خواص آنتی‌ اکسیدانی نیز با اندازه‌ گیری قدرت مهارکنندگی یون آهن اندازه‌ گیری گردید. بر اساس نتایج پژوهش، اختلاف معنی‌ داری در شاخص‌ های اندازه‌گیری شده بین گونه‌های مورد مطالعه مشاهده شد (0/05>p). میزان آنتوسیانین تام در عصاره S. illicifoliu، N. zanardinii و U. lactuca به ترتیب، 1/14±8/31، 1/36±5/19 و 1/84±3/59 میلی‌گرم در 100 گرم وزن خشک اندازه گیری شد (0/05>p). هم چنین محتوای فلاونوئیدی تام نیز بین عصاره های مورد مطالعه به ترتیب 2/71±27/40، 1/14±21/12 و 0/12±0/39 میلی‌گرم کوئرستین بر 100 گرم وزن خشک و قدرت مهارکنندگی یون آهن به ترتیب 0/36±1/21، 0/10±0/67 و 0/12±0/60 بود (0/05>p). در مجموع نتایج حاضر نشان داد که میزان آنتوسیانین، محتوای فلاونوئیدی و قدرت مهارکنندگی یون آهن در عصاره S. illicifolium به شکل معنی‌داری بالاتر از عصاره‌های U. lactuca و N. zanardinii می‌باشد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Comparison of antioxidant properties between extracts of three species of green and brown algae on the northern shores of the Oman Sea

نویسندگان [English]

  • Ali Mahdi Abkenar
  • Eid Mohammad Sarani Yaztapeh
Department of Fisheries, Chabahar Branch, Islamic Azad University, Chabahar, Iran
چکیده [English]

The presence of macroalgae, are important in aquatic habitats. Nowadays, this plants have been receiving increasing attention by many researchers as a promising natural rich sources of antioxidants. They have displayed numerous advantageous effects on biological activities, including antioxidants and cytotoxicity. In this regard, at the present study, the antioxidant properties of three species of native macroalgae to the northern coast of the Oman Sea (Sistan and Baluchestan province) were studied and compared. Sampling was carried out in autumn and winter of 2018 on the northern coast of the Oman Sea (Chabahar Gulf). The samples included one species of green (Ulva lactuca) and two brown (Sargassum illicifolium and Nizamuddinia zanardinii) algae. These species are predominantly found on the northern shores of the Oman Sea. After sampling, the algae were washed with sea water and tap water. The prepared samples were then dried and powdered with an electric mill. The extract was prepared in three steps. The first and second stages was carried out with distilled water and the third stage with methanol solvent. The total content of anthocyanin and flavonoid were measured by spectrophotometry method. Antioxidant properties were also measured by ferric reducing antioxidant power. Based on the results, a significant difference were observed in the studied indices between the studied species (p<0.05). Total anthocyanin contents in S. illicifolium, N. zanardinii and U. lactuca extracts was 8.31±1.14, 5.19±1.36 and 3.59±1.84 mg per 100 g dry weight, respectively (p<0.05). However, total flavonoid content between the studied extracts was 27.40±2.71, 21.12±1.14 and 0.39±0.12 mg per 100 g QE per 100 g dry weight and ferric reducing antioxidant power was 1.21±0.36, 0.67±0.10 and 0.60±0.12, respectively (p<0.05). In conclusion, the results of this study indicate that the total amount of anthocyanin and flavonoid contents as well as ferric reducing antioxidant power in S. illicifolium extract were significantly higher than U. lactuca and N. zanardinii extracts.

کلیدواژه‌ها [English]

  • Antioxidants
  • anthocyanin
  • flavonoid
  • Oman Sea
  • FRAP
  • Sargassum illicifolium
  1. Kosanić, M., Ranković, B. and Stanojković, T., 2015. Biological activities of two macroalgae from Adriatic coast of Montenegro. Saudi J Biol Sci. 22(4): 390-397. Available from: https://linkinghub.elsevier.com/retrieve/pii/S1319562 X14001417
  2. Kuda, T., Tsunekawa, M., Goto, H. and Araki, Y., 2005. Antioxidant properties of four edible algae harvested in the Noto Peninsula, Japan. J Food Compos Anal. 18(7): 625-633. Available from: https://linkinghub.elsevier.com/ retrieve/pii/S0889157504001279
  3. Manilal, A., Sujith, S., Sabarathnam, B., Kiran, G.S., Selvin, J. and Shakir, C., 2010. Bioactivity of the red algae Asparagopsis taxiformis collected from the Southwestern coast of India. Brazilian J Oceanogr. 58(2): 93-100. Available from: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-87592010000200002&lng= en&tlng=en
  4. Marinho, G.S., Sørensen, A.D.M., Safafar, H., Pedersen, A.H. and Holdt, S.L., 2019. Antioxidant content and activity of the seaweed Saccharina latissima: a seasonal perspective. J Appl Phycol. 31(2): 1343-1354. Available from: http://link.springer.com/10.1007/s10811-018-1650-8
  5. Pereira, L., 2018. Seaweeds as Source of Bioactive Substances and Skin Care Therapy-Cosmeceuticals, Algotheraphy, and Thalassotherapy. Cosmetics. 5(4):68. Available from: http://www.mdpi.com/2079-9284/5/4/68
  6. Miyashita, K., Narayan, B., Tsukui, T., Kamogawa, H., Abe, M. and Hosokawa, M., 2011. Brown Seaweed Lipids as Potential Source of Omega-3 PUFA in Biological Systems. In: Handbook of Marine Macroalgae. Chichester, UK: John Wiley & Sons, Ltd. 329-339. Available from: https://onlinelibrary.wiley.com/doi/10.1002/9781119977087.ch16
  7. Miyashita, K., Mikami, N. and Hosokawa, M., 2013. Chemical and nutritional characteristics of brown seaweed lipids: A review. J Funct Foods. 5(4):1507-1517. Available from: https://linkinghub.elsevier.com/ retrieve/pii/S1756464613002181
  8. Gharanjik, B.M., 2000. The marine algae of the Sistan and Baluchestan Province, Iran. Iran J Fish Sci. 2(2): 57-70. Available from: http://jifro.ir/article-1-3180-en.html
  9. Pimentel, F.B., Alves, R.C., Rodrigues, F., Beatriz, M. and Oliveira, P.P., 2018. Macroalgae-Derived Ingredients for Cosmetic Industry-An Update. cosmetics. 5(1): 2. https://doi.org/10.3390/cosmetics5010002. Available from: www.mdpi.com/journal/cosmetics
  10. Mohammadi, E., 2016. Comparison of Physicochemical and functional properties of two brown seaweeds species of (Nizimuinia zanardini and Iyengaria stellata), Qeshm. Gorgan University of Agricultural Sciences and Natural Resources.
  11. Dominguez, H. and Loret, E.P., 2019. Ulva lactuca, A Source of Troubles and Potential Riches. Mar Drugs. 17(6): 357. Available from: https://www.mdpi.com/1660-3397/17/6/357
  12. Kumar, C.S., Ganesan, P., Suresh, P.V. and Bhaskar, N., 2008. Seaweeds as a source of nutritionally beneficial compounds-a review. J Food Sci Technol. 45(1): 1-13. Available from: https://eurekamag.com/research/021/728/ 021728823.php
  13. Moulazadeh, A., Ranjbar, R., Dakhili Ardestani, A., Keshavarzi, A., Karimzadeh, F. and Rahnavard, M., 2021. Evaluation of Phenolic Content, Antioxidant Activity and Cytotoxic Effects of Ulva lactuca and Hypnea musiformis Marine Algae on MDA-MB-468 Cell Line. J Fasa Univ Med Sci. 11(3): 3921-3928. Available from: https://journal. fums.ac.ir/article-1-2506-en.html
  14. Prasedya, E.S., Martyasari, N.W.R., Apriani, R., Mayshara, S., Fanani, R.A. and Sunarpi, H., 2019. Antioxidant activity of Ulva lactuca L. from different coastal locations of Lombok Island, Indonesia. 203 p. Available from: http://aip.scitation.org/doi/abs/10.1063/1.5141281
  15. Zaatout, H., Ghareeb, D, Abd-Elgwad, A. and Ismael, A., 2019. Phytochemical, antioxidant, and anti-inflammatory screening of the Egyptian Ulva lactuca methanolic extract. Rec Pharm Biomed Sci. 33-38. Available from: https://rpbs.journals.ekb.eg/article_31749.html
  16. Fomenko, S.E., Kushnerova, N.F., Sprygin, V.G. and Momot, T.V., 2016 . The antioxidant and stress-protective properties of an extract from the green alga Ulva lactuca Linnaeus, 1753. Russ J Mar Biol. 42(6): 509-514. Available from: http://link.springer.com/10.1134/S1063074016060031
  17. Khairy, H.M. and El-Sheikh, M.A., 2015. Antioxidant activity and mineral composition of three Mediterranean common seaweeds from Abu-Qir Bay, Egypt. Saudi J Biol Sci. 22(5): 623-630.
  18. Lee, J.C., Hou, M.F., Huang, H.W., Chang, F.R., Yeh, C.C. and Tang, J.Y., 2013. Marine algal natural products with anti-oxidative, anti-inflammatory, and anti-cancer properties. Cancer Cell Int. 13(1): 55. Available from: https://cancerci.biomedcentral.com/articles/10.1186/1475-2867-13-55
  19. Kokabi, M., Yousefzadi, M., Ali ahmadi, A., Feghhi, M.A. and Keshavarz, M., 2013. Antioxidant Activity of Extracts of Selected Algae from the Persian Gulf, Iran. J Persian Gulf. 4(12): 45-50. Available from: http://jpg.inio. ac.ir/article-1-180-en.html
  20. Hafezieh, M., Moradi, Y., Pourkazemi, M., Dadgar, S. and Sharifian, M., 2016. Determination of proximal and chemical composition of Sistan and Baluchistan province geographical beaches strain of Sargassum ilicifolium. Iran Sci J. 25(4): 133-144. Available from: https://isfj.areeo.ac.ir/article_110305.html
  21. Mohammadi, E., Shabanpour, B. and Kordjazi, M., 2019. Effect of Nizimuddinia zanardini aqueous extract against human pathogenic microbes and evaluating its antioxidant activity. J Mar Biol. 10(4): 75-82. Available from: http://jmb.iauahvaz.ac.ir/article-1-714-en.html
  22. Sahragard, K., Tabarsa, M. and Ahmadi, H., 2021. Isolation, purification, anti-diabetic and antioxidant properties of fucoidan from brown seaweed Sargassum ilicifolium. J Fish. 74(2): 223-234. Available from: https://jfisheries.ut. ac.ir/article_81746.html
  23. Yende, S.R., Arora, S.K. and Ittadwar, A.M., 2021. Antioxidant and Cognitive Enhancing Activities of Sargassum ilicifolium and Padina tetrastromatica in Scopolamine Treated Mice. J Biol Act Prod from Nat. 11(1): 11-21. Available from: https://www.tandfonline.com/doi/full/10.1080/22311866.2020.1871071
  24. Swati, S., Giriwono, P.E., Iskandriati, D. and Andarwulan, N., 2021. Screening of In-Vitro Anti-Inflammatory and Antioxidant Activity of Sargassum ilicifolium Crude Lipid Extracts from Different Coastal Areas in Indonesia. Mar Drugs. 19(5): 252. Available from: https://www.mdpi.com/1660-3397/19/5/252
  25. Arguelles, E.D.L.R., 2021. Evaluation of Antioxidant Capacity, Tyrosinase Inhibition, and Antibacterial Activities of Brown Seaweed, Sargassum ilicifolium (Turner) C. Agardh 1820 for Cosmeceutical Application. J Fish Environ. 45(1): 64-77. Available from: https://www.ukdr.uplb.edu.ph/journal-articles/84
  26. Eldrin De Los Reyes, A. and Arsenia Basaran, S., 2020. Bioactive properties of Sargassum siliquosum J. Agardh (Fucales, Ochrophyta) and its potential as source of skin-lightening active ingredient for cosmetic application. J Appl Pharm Sci. Available from: https://www.japsonline.com/counter.php?aid=3165
  27. Gharanjik, B. and Abkenar, A.M., 2000. Identification of Seaweed in Sistan and Baluchestan Province Costal Zone. Iran Sci Fish J. 9(1): 37-48. Available from: https://isfj.areeo.ac.ir/article_115913.html
  28. Mahdi Abkenar, A., 2013. Investigation of alginates in brown algae Sargassum illicifolium, Cystoseira indica and Nizamuddinia zanardinii on the coasts of Sistan and Baluchestan province. Tehran; Available from: http://fipak. areeo.ac.ir/site/catalogue/18784348
  29. Sánchez-Machado, D.I., López-Cervantes, J., López-Hernández, J. and Paseiro-Losada, P., 2004. Fatty acids, total lipid, protein and ash contents of processed edible seaweeds. Food Chem. 85(3): 439-444. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0308814603003819
  30. Chang, C.C., Yang, M.H., Wen, H.M. and Chern, J.C., 2002. Estimation of total flavonoid content in propolis by two complementary colorimetric methods. J Food Drug Anal. 10: 178-182.
  31. Muanda, F.N., Soulimani, R., Diop, B. and Dicko, A., 2011. Study on chemical composition and biological activities of essential oil and extracts from Stevia rebaudiana Bertoni leaves. LWT - Food Sci Technol. 44(9): 1865-1872. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0023643810004160
  32. Lee, H.J., Kim, Y.A., Ahn, J.W. and Seo, Y.W., 2004. Screening of peroxynitrite and DPPH radical scavenging activities from salt marsh plants. Korean J Biotechnol Bioeng. 19(1): 57-61.
  33. Sellimi, S., Younes, I., Ayed, H.B., Maalej, H., Montero, V. and Rinaudo, M., 2015. Structural, physicochemical and antioxidant properties of sodium alginate isolated from a Tunisian brown seaweed. Int J Biol Macromol. 72: 1358-1367. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0141813014006928
  34. Cox, S., Abu-Ghannam, N. and Gupta, S., 2010. An assessment of the antioxidant and antimicrobial activity of six species of edible Irish seaweeds. Int Food Res J. 17(1): 205-220.
  35. Sumathi, S. and Krishnavenim, M., 2012. Preliminary Screening screening, antioxidant and antimicrobial potential of Chaetomorpha antennina and Caulerpa scalpelliformis in vitro study. Int J Environ Sci. 2(3): 2312-2320.
  36. Zubia, M., Robledo, D. and Freile-Pelegrin, Y., 2007. Antioxidant activities in tropical marine macroalgae from the Yucatan Peninsula, Mexico. J Appl Phycol. 19(5): 449-458. Available from: http://link.springer.com/10.1007/s 10811-006-9152-5
  37. Kokilam, G., Vasuki, S. and Sajitha, N., 2013. Biochemical composition, alginic acid yield and antioxidant activity of brown seaweeds from Mandapam region, Gulf of Mannar. J Appl Pharm Sci. 3: 99-104.
  38. Duan, X.J., Zhang, W.W., Li, X.M. and Wang, B.G., 2006. Evaluation of antioxidant property of extract and fractions obtained from a red alga, Polysiphonia urceolata. Food Chem. 95(1): 37-43.
  39. Park, P.J., Shahidi, F. and Jeon, Y.J., 2004. Antioxidant activities Of enzymatic extracts from an edible Seaweed Sargassum horneri using esr spectrometry. J Food Lipids. 11(1): 15-27. Available from: https://onlinelibrary.wiley. com/doi/10.1111/j.1745-4522.2004.tb00257.x
  40. Lim, S.N., Cheung, P.C.K., Ooi, V.E.C. and Ang, P.O., 2002. Evaluation of antioxidative activity of Extracts from a Brown Seaweed, Sargassum siliquastrum. J Agric Food Chem. 50(13): 3862-3866. Available from: https://pubs.acs. org/doi/10.1021/jf020096b
  41. Zakaria, N.A., Ibrahim, D. and Sulaiman, S.F., 2011. Supardy A. Assessment of antioxidant activity, total phenolic content and in vitro toxicity of Malaysian red seaweed, Acanthophora spicifera. J Chemaceutical Res. 3(3): 182-191.
  42. Panche, A.N., Diwan, A.D. and Chandra, S.R., 2016. Flavonoids: an overview. J Nutr Sci. 5: e47. Available from: https://www.cambridge.org/core/product/identifier/S2048679016000410 /type/journal_article
  43. Athukorala, Y., Kim, K.N. and Jeon, Y.J., 2006. Antiproliferative and antioxidant properties of an enzymatic hydrolysate from brown alga, Ecklonia cava. Food Chem Toxicol. 44(7): 1065-1074. Available from: https://linking hub.elsevier.com/retrieve/pii/S0278691506000068
  44. Jiménez-Escrig, A., Jiménez-Jiménez, I., Pulido, R., Saura-Calixto, F., 2001. Antioxidant activity of fresh and processed edible seaweeds. J Sci Food Agric. 81(5): 530-534. Available from: https://doi.org/10.1002/jsfa.842
  45. Akhbari, A.M., Haeri, M. and Babaei, M., 2014. Investigation of anthocyanin contents and cytotoxic activity in different extracts of Fruit Peel of Solanum melongena L.. Qom Univ Med Sci J. 8(3): 11-17. Available from: http:// journal.muq.ac.ir/article-1-178-fa.html
  46. Rahbarmehr, H., 2015. Evaluation of antioxidant activity of Caspian Sea red algae Gracilaria gracilis and assessment of antimicrobial properties of silver nanoparticles synthesized from the algae extractNo Title. University of Guilan.
  47. Dorman, H.J.D., Peltoketo, A., Hiltunen, R. and Tikkanen, M.J., 2003. Characterisation of the antioxidant properties of de-odourised aqueous extracts from selected Lamiaceae herbs. Food Chem. 83(2): 255-262.
  48. Juntachote, T. and Berghofer, E., 2005. Antioxidative properties and stability of ethanolic extracts of Holy basil and Galangal. Food Chem. 92(2): 193-202. Available from: https://linkinghub.elsevier.com/retrieve/pii/S030881460 4005497
  49. Meir, S., Kanner, J., Akiri, B. and Philosoph-Hadas, S., 1995. Determination and Involvement of Aqueous Reducing Compounds in Oxidative Defense Systems of Various Senescing Leaves. J Agric Food Chem. 43(7): 1813-1819. Available from: https://pubs.acs.org/doi/abs/10.1021/jf00055a012
  50. Su, X.Y., Wang, Z.Y. and Liu, J.R., 2009. In vitro and in vivo antioxidant activity of Pinus koraiensis seed extract containing phenolic compounds. Food Chem. 117(4): 681-686. Available from: https://linkinghub.elsevier.com/ retrieve/pii/S0308814609005342
  51. Ghaemi, V., Alizadeh Doughikollaee, E. and Kordjazi, M., 2018. Evaluation of antioxidant activity of protein hydrolysate from Common Kilka (Clupeonella cultriventris caspia) and brown algae Colpomenia sinuosa extract. Aquat Physiol Biotechnol. 5(4): 1-25. Available from: https://japb.guilan.ac.ir/article_2700.html
  52. Etemadian, Y., Khanipour, A., Shabanpour, B., Kordjazi, M., Ghaemi, V. and Zahmatkesh, Y., 2017. Investigating the pharmacological properties of 5 native brown algae in the southern waters of the country and promoting them for breeding. Adv Aquac Sci J. 1(1): 43-52. Available from: https://aasj.areeo.ac.ir/article_113475. html
  53. Fellah, F., Louaileche, H., Dehbi-Zebboudj, A. and Touati, N., 2017. Seasonal variations in the phenolic compound content and antioxidant activities of three selected species of seaweeds from Tiskerth islet, Bejaia, Algeria. J Mater Environ Sci. 8(12): 4451-4456. Available from: http://www.jmaterenvironsci.com/Document/ vol8/vol8_N12/470-JMES-3106-Fellah.pdf
  54. Ganesan, P., Kumar, C.S. and Bhaskar, N., 2008. Antioxidant properties of methanol extract and its solvent fractions obtained from selected Indian red seaweeds. Bioresour Technol. 99(8): 2717-2723.
  55. Moure, A., Cruz, J.M., Franco, D., Domı́nguez, J.M., Sineiro, J. and Domı́nguez, H., 2001. Natural antioxidants from residual sources. Food Chem. 72(2): 145-171. Available from: https://linkinghub.elsevier.com/retrieve/pii/ S0308814600002235
  56. Gülçin, İ., 2015. Fe3+–Fe2+ Transformation Method: An Important Antioxidant Assay. 233-246. Available from: http://link.springer.com/10.1007/978-1-4939-1441-8_17
  57. Rajauria, G., 2019. In-Vitro Antioxidant Properties of Lipophilic Antioxidant Compounds from 3 Brown Seaweed. Antioxidants. 8(12): 596. Available from: https://www.mdpi.com/2076-3921/8/12/596
  58. Syad, A.N., Shunmugiah, K.P. and Kasi, P.D., 2013. Antioxidant and anti-cholinesterase activity of Sargassum wightii. Pharm Biol. 51: 1401-1410.
  59. Moulazadeh, A., Ranjbar, R., Dakhili Ardestani, A., Keshavarzi, A., Karimzadeh, F., Karimzadeh, F., Rahnavard, M., Zarei Jeliani, Z. and Najafipour, S., 2021. Evaluation of Phenolic Content, Antioxidant Activity and Cytotoxic Effects of Ulva lactuca and Hypnea musiformis Marine Algae on MDA-MB-468 Cell Line. J Fasa Univ Med Sci. 11(3): 3921-3928. Available from: url: http://jabs.fums.ac.ir/article-1-2506-en.html
  60. Van Alstyne, K.L., Koellermeier, L. and Nelson, T.A., 2007. Spatial variation in di methyl sulfonio propionate (DMSP) production in Ulva lactuca (Chlorophyta) from the Northeast Pacific. Mar Biol. 150(6): 1127-1135. Available from: http://link.springer.com/10.1007/s00227-006-0448-4
  61. Rossa, M.M., de Oliveira, M.C., Okamoto, O.K., Lopes, P.F. and Colepicolo, P., 2002. Effect of visible light on superoxide dismutase SOD activity in the red alga Gracilariopsis tenuifrons (Gracilarials, Rhodophyta). J Appl Phycol. 14: 151-157.
  62. Karsten, U., Karsten, A.U., Lembcke, A.S. and Schumann, A.R., 2007. The effects of ultraviolet radiation on photosynthetic performance, growth and sunscreen compounds in aeroterrestrial biofilm algae isolated from building facades. Planta. 225(4): 991-1000. doi: 10.1007/s00425-006-0406-x. Available from: www.epsag.uni-goettingen.de