Pengaruh Praperlakuan Alkali dan Asam terhadap Karakteristik Mutu Bakto Agar dari Rumput Laut Gelidium sp

Ekstraksi bakto agar dari rumput laut merah Gelidium sp. asal Pameungpeuk, Jawa Barat dengan praperlakuan alkali dan asam telah diteliti. Pada praperlakuan alkali digunakan NaOH dengan variasi konsentrasi 4, 5, dan 6%. Asam yang digunakan yaitu CH3COOH dengan variasi konsentrasi 0,5% dan 1,0%. Parameter mutu yang diamati meliputi kadar air, kadar abu, kadar abu tak larut asam, kadar sulfat, gugus fungsi, rendemen agar, kekuatan gel, viskositas, titik leleh dan titik jendal, sineresis, dan angka lempeng total. Bakto agar terbaik diperoleh dari praperlakuan dengan konsentrasi NaOH 4% dan CH3COOH 0,5% yang telah memenuhi beberapa persyaratan mutu bakto agar komersial untuk parameter kekuatan gel, kadar air, kadar abu, dan kadar abu tak larut asam. Karakteristik mutu dari praperlakuan tersebut adalah kadar air 13,69±1,02%, kadar abu 4,24±1,28%, kadar abu tak larut asam 0,54±0,25%, kadar sulfat 1,55±0,36%, rendemen 9,19±2,21%, kekuatan gel 1464,98±109,09 g/cm2, viskositas 42,75±24,40%, sineresis 2,76±0,12%, titik jendal 20,50±2,12 °C, dan titik leleh 95,25±1,06 °C. Praperlakuan dengan konsentrasi tersebut juga memiliki nilai Angka Lempeng Total (ALT) yang sama dengan bakto agar komersial. AbstractBacto agar extraction from red seaweed Gelidium sp. from Pameungpeuk, West Java with alkali and acid pretreatment had been conducted. NaOH with concentration of 4, 5, and 6% was used for alkali pretreatment while CH3COOH at concentrations of 0.5% and 1.0% (v/v) was used for acid pretreatment. The quality parameters investigated were moisture content, ash content, acid insoluble ash, sulphate content, functional groups, yield, gel strength, viscosity, melting point, gelling point, syneresis, and total plate count. The best quality of bacto agar was obtained by using 4% alkali pretreatment and 0.5% CH3COOH. This pretreatment has fulfilled the specification of commercial bacto agar for moisture, ash, acid inslouble ash content, and gel strength parameter. The properties of bacto agar from this pretreatment were moisture content 13.69±1.02%, ash content 4.24±1.28%, acid insoluble ash content 0.54±0.25%, sulphate content 1.55±0.36%, yield 9.19±2.21%, gel strength 1464.98±109.09 g/cm2, syneresis 2.76±0.12%, gelling point 20.50±2.12 °C, and melting point 95.25±1.06 °C. This pretreatment also gave the same result as the commercial bacto agar for the total plate count.

Strategies for the Regeneration of Paphiopedilum callosum through Internode Tissue Cultures Using Dark–light Cycles

Paphiopedilum spp. is one of the most commercially popular orchids because of its variety of shapes, sizes, and colors. However, it is at risk for extinction because of its exploitation. Regeneration of orchid plants using internode segments is extremely difficult. In this study, young P. callosum plants (1.5 cm) were exposed to eight dark–light cycles (14 days of dark and 1 day of light) for stem elongation to increase the number of nodes to obtain internode tissues. After 75 days of culture, the highest callogenesis (31.25%) was achieved when internode tissue was cultured on liquid Schenk and Hildebrandt (SH) medium containing 30 g·L−1 sucrose, 1.0 mg·L−1 Thidiazuron (TDZ), 1.0 mg·L−1 2,4-Dichlorophenoxyacetic acid (2,4-D), and cotton wool as the support matrix. The optimal media for induction of protocorm-like bodies (PLBs) were the same compositions as previously mentioned and were supplemented with 9 g·L−1 Bacto agar as the gelling agent. PLB clumps (5–6 PLBs/clump) produced the best shoots on medium containing 0.5 mg·L−1 α-Naphthaleneacetic acid (NAA) and 0.3 mg·L−1 TDZ. Among the organic substances tested, 200 g·L−1 potato homogenate (PH) added to Hyponex N016 medium supplemented with 1.0 mg·L−1 NAA, 30 g·L−1 sucrose, 170 mg·L−1 NaH2PO4, 1.0 g·L−1 peptone, and 9 g·L−1 Bacto agar resulted in the best rooting. The rooted plantlets with four to five leaves were acclimatized and had a 100% survival rate. The method presented in this research provides a strategy for the development of highly effective propagation of Paphiopedilum species using ex vitro explants for both conservation and horticultural purposes.

The role of gum induced by Fusarium oxysporum Schlecht. Snyd. et Hans. f.sp. tulipae Apt. in tulip bulbs on growth and development of the pathogen

It was showed that gums induced by Fusarium oxysporum f.sp. tulipae in tulip bulbs applied to mineral Czapek-Dox Broth with Bacto Agar (CzDA) medium, containing sucrose substantially stimulated abundant growth of mycelium and sporulation of the pathogen. Addition of arabinose, xylose and their mixture, sugars occurring in tulip gum polysaccharide, to CzDA medium caused that mycelium was very sparse and sporulation was only slightly stimulated by arabinose. Mycelium growth on mineral CzDA medium without sucrose, was poor and sparse but addition of gum to the medium caused formation of abundant mycelium and increased sporulation of the pathogen. It is possible that polysaccharide of tulip gum may act mainly as elicitor and partially as substrate in regulation of mycelium growth and sporulation of Fusarium oxysporum f.sp. tulipae.

PENGARUH BAP (BENZIL ADENIN PURIN) DAN NAA (NAPHTHALEN ACETIC ACID) TERHADAP EKSPLAN TANAMAN TURI (Sesbania grandiflora) DALAM MEDIA MULTIPLIKASI In Vitro

Turi merupakan leguminosa pohon. Perbanyakan turi secara vegetatif sulit dilakukan karena kemampuan turi untuk tumbuh kembali setelah dilakukan pemotongan sangat rendah. Penelitian dalam upaya perbanyakan turi melalui metode multiplikasi tanaman turi secara in vitro telah dilakukan di Laboratorium Kultur Jaringan. Eksplan yang digunakan adalah kotiledon, daun dan hipokotil steril tanaman turi. Media dasar yang digunakan adalah MS (Murashige skoog) yang diperkaya dengan vitamin. Sebagai sumber energi digunakan sukrosa sebanyak 30 g/l dan bacto agar 8g/l. Penelitian ini terdiri dari perlakuan BAP sebagai salah satu jenis sitokinin) secara tunggal yaitu MS + BAP 1 mg/l dan MS + BAP 2 mg/l, dan kombinas BAP dengan NAA (sebagai salah satu jenis auksin) yaitu MS + BAP 1mg/l + NAA 0,08 mg/l, MS + BAP 2 mg/l + NAA 0,08 mg/l. Hasil penelitian menunjukkan bahwa kombinasi auksin dan sitokinin mampu memperbanyak shootled turi.Kata kunci: turi, ksplan, Benzil Adenin Purin, Naphthalen acetic acid, in vitro

Bacto-Agar and Commercial Agar as Binder for Porous Zinc Anode

The use of synthetic binder led to environmental issues due to undergo chemical processes in manufacturing sector and even made it expensive material. Therefore, the present study focused on use of natural binder for porous zinc (Zn) anode because its advantages of abundance in raw material, biodegradable, environmental acceptability and cost effectiveness. Bacto-agar and commercial agar powder were selected as natural binder and both agars were characterized their morphologies using the scanning electron microscopy (SEM). The SEM images showed the difference in morphological structure between porous Zn anode with Bacto-agar binder and porous Zn anode with commercial agar binder. Bacto-agar binder possesses smooth surface compare to commercial agar binder indicated that Zn powder successfully mix with Bacto-agar.

In Vitro Culture and Rooting of Diospyros virginiana L.

The hard, strong, very close-grained wood of common persimmon (Diospyros virginiana L.; Ebenaceae) is desirable for specialty products such as golf club heads, percussion sticks, billiard cues, and for wood turnery. The edible fruit of cultivated varieties is sold as pulp for use in puddings, cookies, cakes, and custards. Persimmon is usually propagated by grafting. Own-rooted clonal persimmon could offer several advantages to specialty fruit growers such as elimination of grafting, graft incompatibility issues, and improved rootstocks for variety testing. Four mature, grafted (male and female) persimmon genotypes and one hybrid were used for nodal explant culture. Nodal stem explants were cultured on Murashige and Skoog (MS) medium containing 10 μM zeatin, 3% (w/v) sucrose, and 0.7% (w/v) Bacto agar. Explants were routinely transferred to fresh medium every 3 weeks until shoot cultures were established. All nodal explants excised from grafted greenhouse plants produced at least one viable shoot. For in vitro rooting of microshoots, half-strength MS medium with 0, 5, 10, or 15 μM indole-3-butyric acid (IBA), 0.1 g·L−1 phloroglucinol, 3% (w/v) sucrose, and 0.7% (w/v) Bacto agar were tested with a 10-day dark culture treatment followed by culture in the light. Best rooting (14% to 87%) was achieved on medium containing 5 μM IBA for the common persimmon genotypes with means averaging from 0.5 to 3.9 roots per shoot. Ninety-one percent rooting with 5.3 ± 2.6 roots per shoot was achieved for the hybrid persimmon. Rooted plants were successfully acclimatized to the greenhouse.

New Basal Media for Protocorm-Like Body and Callus Induction of Hybrid Cymbidium

High frequency protocorm-like body (PLB) production from hybrid Cymbidium Twilight Moon ‘Day Light’ has been developed through a new medium, Teixeira Cymbidium (TC) medium. Two new TC media containing variable amounts of macroand micronutrients and other additives, inspired by Winarto and Teixeira (WT) medium for Anthurium and Murashige and Skoog (MS) basal medium were used to induce PLBs and callus. Control medium was research- and industry-standard Vacin and Went (VW) medium. The first TC medium, TCPLB, could induce significantly more PLBs than on VW while high levels of macronutrients in the second TC medium, TCCALLUS, and MS were required to induce callus. All PLB induction media contained 0.1 mg/l α-naphthaleneacetic acid (NAA) and 0.1 mg/l kinetin (KIN), 2 g/l tryptone and 20 g/l sucrose, and solidified with 8 g/l Bacto agar while callusinduction media were identical, except that KIN was substituted by thidiazuron (TDZ). Basal medium had a significant effect on PLB and callus formation. This protocol could be used to induce PLBs and callus from other Cymbidium species or cultivars.