L1 (11): For brackish water organisms. Mix 650 mL distilled H2O and 350 mL filtered seawater. Add L1\u00a0<\/span>medium nutrients and autoclave.<\/span><\/p>\n L1 (24): For brackish water organisms. Prepare L1-Si medium. To each liter prepared, add 200mL distilled,<\/span>mix and autoclave. <\/span><\/p>\n h\/2 Medium: For ammonia loving organisms. Add 1mL of 500mM NH4Cl per liter of L1 medium to give a\u00a0<\/span>final concentration of 500uM ammonia. Autoclave. <\/span><\/p>\n L1+ NH4Cl: For organisms do not love ammonia quite as much. Prepare as for L1 medium but omit the silica\u00a0<\/span>and add 300uL of a 500mM NH4Cl per liter of L1 medium to give a final concentration of 166uM ammonia.<\/span>Autoclave.<\/span><\/p>\n L1 agar: To grow algae on agar, prepare 1 liter of L1 medium and dissolve 9g agar (heat and mix). For test\u00a0<\/span>tubes, dispense dissolved agar medium into tubes, autoclave, and then cool with tubes slanted at an angle. For\u00a0<\/span>Petri plates, autoclave in a flask, cool almost to the gelling point, and then aseptically dispense into sterile Petri\u00a0<\/span>plates. Note: The agar concentration can be varied to produce softer or firmer substrates.<\/span><\/p>\n L1 – Si: Prepare as for L1 medium but omit Na2SiO 3 \u2022 9H2O. This is preferred over L1 medium for organisms\u00a0<\/span>with no silica requirement because less precipitation forms. <\/span><\/p>\n L1 + Se: Extra silicon and selenium are beneficial to some diatom species. Prepare 1 L of L1 medium but use 2\u00a0<\/span>mL of silicate stock, then add 1.0 mL of selenium stock solution (1.29 mg H2SeO 3 \/L distilled H2O). Autoclave. <\/span><\/p>\n L\/10-Si: for more fastidious organisms. Autoclave 1 L of filtered seawater. When cool, aseptically add L1-Si\u00a0<\/span>nutrients at one tenth concentration (i.e., 100uL per L). <\/span><\/p>\n L1\/25-Si: for even more delicate organisms. This is more than a 1\/25 dilution of f\/2-Si medium. We autoclave 1\u00a0<\/span>L of seawater in a Teflon-lined bottle. Wait for the autoclaved seawater to cool to room temperature <\/span><\/p>\n L1\/25-Si + CCMP1320 as food: for growing mixotrophs or heterotrophs. Prepare f\/50 and aseptically add\u00a0<\/span>50uL of healthy, moderately dense culture of CCMP1320.<\/span><\/p>\n L1m: This medium is used to test for contamination by methylaminotrophic bacteria. To 1L of L1 medium,\u00a0<\/span>add 1 g methylamine \u2022 HCl, mix until dissolved and autoclave.<\/span><\/p>\n L1p: This medium is used to test for contamination by non- methylaminotrophic bacteria and fungi. It can also\u00a0<\/span>be used by organisms that require an organic carbon source. To 1 L of L1 medium,add 1 g Bacto-peptone, mix\u00a0<\/span>until dissolves and autoclave. <\/span><\/p>\n L1pm: This general medium is used to test for contamination by bacteria and fungi. To 1L of L1 medium add 1<\/span>g Bacto-peptone and 1 g methylamine \u00b7 HCl, mix until dissolved and autoclave. <\/span><\/p>\n L1 + NPM: For organisms requiring an organic carbon source. Add L1 nutrients to 900 mL of seawater and\u00a0<\/span>autoclave. After cooling, aseptically add 100 mL of organic stock solution (for recipe, see below). Dispense\u00a0<\/span>aseptically into test tubes. Or, you can add sterile NPM to each tube aseptically. We use an approximately 10%\u00a0<\/span>solution of NPM in L1 medium. <\/span><\/p>\n Prov: Add 20 mL of a 1:50 dilution of Alkaline Soil Extract for a final volume of 1L of L1-Si medium (see\u00a0<\/span>soil extract recipe below). At NCMA, we use the term Prov whether using a L1 base or a f\/2 base. <\/span><\/p>\n
![\"Organics](\"https:\/\/www.leadingtec.cn\/wp-content\/uploads\/2016\/06\/20160602163548.png\")
<\/a>