https://media.medfarm.uu.se/play/kanal/618This collection of videos explain techniques and workflow in the Pharmacognosy lab.svCopyright (C) 2026 Uppsala universitet, MedfarmDoITThis video is an introduction to extraction of natural products. It gives an overview of preparation of samples, extraction techniques, to finish with a dry extract ready for separation or bioassay. Demonstrator and speaker is Dr Hesham El Seedi. Video was recorded in May 2020.https://media.medfarm.uu.se/play/video/11374Sun, 10 May 2020 17:37:52 +0000Extraction is followed by separation, and commonly used techniques are liquid-liquid extraction and, as demonstrated here, solid phase extraction. In this video a crude extract is fractionated into a limited number of fractions, using a stepwise gradient. The SPE cartridge contains reverse phase (C18) material: fractions are then eluted by using solvents containing increasing concentrations of organic modifier. Having a number of fractions in hand, they are then subject to analyses. The analyses are adapted to the purpose: here a quick check of chemical content by thin layer chromatography is used, but analyses of fractions are often also made by HPLC, LCMS or bioassays as demonstrated in later videos. Demonstrator and speaker is Dr Hesham El Seedi. The video was recorded in May 2020.https://media.medfarm.uu.se/play/video/11376Sun, 10 May 2020 19:40:18 +0000MPLC - Medium Pressure Liquid Chromatography - is used for separation of large amounts of extract. The aim is not necessarily to get pure compounds in this step, but to e.g. obtain fractions for further separation or testing, or to enrich your target compound into a few fractions. As the name implies, MPLC operates at lower pressure than HPLC and uses columns containing larger particles. Separation is thus not as powerful as HPLC, but flow rates are high, separations are quick, and columns are cheap (disposable). The system is coupled to an automatic fraction collector, that changes tubes based on time (e.g. one tube per minute). HPLC - High Performance Liquid Chromatography - is used both for analytical and preparative purposes. (See also - and read the text to - the video "Fractionation and separation - Preparative chromatography and columns of different sizes".) The HPLC in the current video is equipped with an autosampler, which enables unattended analyses. HPLC on reverse phase is often used for the final purification of natural products. Demonstrator is Dr Hesham El Seedi. Video was recorded in May 2020.https://media.medfarm.uu.se/play/video/11377Sun, 10 May 2020 19:51:21 +0000The video show the difference between analytical and preparative HPLC columns. In principle, preparative HPLC only means that you collect compound/s eluting form the column, and by using larger scale columns you can increase the amount injection and the amount collected. The first column shown is a typical analytical column, which is what you encounter in the analytical chemistry lab. Common dimensions are inner diameter of 4.6 mm, and lengths of 150 to 250 mm. Flow rate is ~ 1 ml/min. The next column is sometimes referred to as a "semi-reparative column": inner dimension is 10 mm, and flow rate is ~4 ml/min. This column is 4x the size of the analytical column, and can thus tolerate 4 times as much sample injected while giving the same separation power. Last column is the largest HPLC columns that we have in our lab, with inner dimension of 21 mm, and is typically operated at flow rates of ~16 ml/min. The column is 4x the size of the "semi prep" (10 mm id column) and as such, can be loaded with even more sample. For us, this column means we can inject 100-1000 mg of sample, to isolate compounds in the 10 mg scale or more, but it also requires access to pumps that can operate at higher flow rates. This video should be seen in connection to the Q&A session. Demonstrator is Quentin Laborde. Video was recorded in May 2020.https://media.medfarm.uu.se/play/video/11352Fri, 08 May 2020 15:03:14 +0000Fraction collection is a crucial part of preparative chromatography, which can be done in different ways. Here, the use of an automatic fraction collector is demonstrated after preparative RP-HPLC. In this case, collection is time based, but collection may also be triggered by peak detection using UV or MS. Demonstrator and speaker is Quentin Laborde. Video was recorded in May 2020.https://media.medfarm.uu.se/play/video/11353Fri, 08 May 2020 15:05:30 +0000This video demonstrates the use of size exclusion chromatography (gel filtration). This particular (Sephadex PD10) column is used for the crude separation of small and large molecules, with a cut off of ca 1000 Da. Speaker and demonstrator is Jayani Gamagi, and the video was recorded in May 2020.https://media.medfarm.uu.se/play/video/11345Fri, 08 May 2020 13:24:09 +0000This video demonstrates mass spectrometry in use at the Pharmacognosy lab. Specifically, high resolution QTof MS connected to nanoUPLC (Ultra Performance Liquid Chromatography), and low resolution ion trap MS are demonstrated. What kind of information do the different instruments give, and when should the different instruments be used? Demonstrator is Dr Hesham El Seedi, and the video was recorded in May 2020.https://media.medfarm.uu.se/play/video/11348Fri, 08 May 2020 13:57:38 +0000This video shows how NMR samples are prepared. Choice of suitable solvents are discussed. Video ends with a visit to the NMR platform at BMC. Demonstrator is Dr Sunithi Gunasekera and speaker Dr Luke Robertson. Video was recorded in May 2020.https://media.medfarm.uu.se/play/video/11373Sun, 10 May 2020 15:26:41 +0000NMR is the key to the chemical structure of a new natural product. This video shows a sample being run at the NMR platform at BMC. Demonstrator and speaker is Dr Hesham El Seedi. Video was recorded in May 2020.https://media.medfarm.uu.se/play/video/11379Sun, 10 May 2020 21:24:01 +0000This video explains the use of bioassays in natural products research, focusing on antimicrobial assays. Both disc/agar diffusion methods and tests in solution are explained. Speaker and demonstrator is Dr Scott Jarmusch.https://media.medfarm.uu.se/play/video/11347Fri, 08 May 2020 13:47:46 +0000